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tlv320aic27 stereo audio codec slas253 march 2000 1 post office box 655303 ? dallas, texas 75265 3.3-v or 5-v operation 18-bit stereo codec s/n ratio >95 db multiple stereo input mixer mono and stereo volume control 48-pin tqfp package power management features low-power implementation four dac channels, stereo adc balanced mixer architecture variable rate audio and modem support analog 3d stereo enhancement line level outputs master/slave id selection ac97 rev. 2.1 compliant complete ti-dsp-codec solution description the tlv320aic27 comprises a stereo 18-bit codec (that is, 2 adcs and 4 dacs), plus a comprehensive analog mixer with four sets of stereo inputs, plus one phone input, two microphone inputs, and one pc-beep input. additionally, on-chip reference circuits generate the necessary bias voltages for the device, and a bidirectional serial interface allows transfer of control data, dac, and adc words to and from the ac'97 controller. the tlv320aic27 is fully compliant with revision 2.1 of the ac'97 specification. the tlv320aic27 has the adc and dac functions implemented using oversampled, or sigma-delta, converters and uses on-chip digital filters to convert these one-bit signals to and from the 48 ksps, 16/18-bit pcm words that the ac'97 controller requires. the digital and analog sections of the device are powered separately to optimize performance, and 3.3-v digital and 5-v analog supplies may be used on the same device to further optimize performance. digital ios are 5-v tolerant when the analog supplies are 5 v. therefore, the tlv320aic27 may be connected to a controller running on 5-v supplies, but use 3.3 v for the digital section of the tlv320aic27. the tlv320aic27 is also capable of operating with a 3.3-v supply only (digital and analog). when using the tlv320aic27 codec, the ac'97 controller may be selected from texas instruments family of dsps. the combination of the computing power of the ti dsp and the high audio performance of the tlv320aic27 constitutes a complete solution for various applications. the ability to power down sections of the device selectively, and the option to alternate the master clock, and hence sample rates, makes such applications as telecommunications, audio, teleconferencing, and usb, possible. additional features added to the intel ? ac'97 specification, such as the eapd (external amplifier power down) bit and internal connection of pc beep to the outputs when the device is reset are supported, as well as optional features such as variable sample rate support. there are four modes of operation. basic (2-channel) 6-channel i 2 s quad modem esd sensitive device. this device is manufactured on a cmos process. it it therefore generically susceptible to damage from excessive static voltages. proper esd precautions must be taken during handling and storage of this device. as per jedec specifications a112-a and a113-b, this product requires specific storage conditions prior to surface mount assembly. it has bee n classified as having a moisture sensitivity level of 2 and as such will be supplied in vacuum-sealed moisture barrier bags. copyright ? 2000, texas instruments incorporated production data information is current as of publication date. products conform to specifications per the terms of texas instruments standard warranty. production processing does not necessarily include testing of all parameters. please be aware that an important notice concerning availability, standard warranty, and use in critical applications of texas instruments semiconductor products and disclaimers thereto appears at the end of this data sheet. intel is a trademark of intel corporation.
tlv320aic27 stereo audio codec slas253 march 2000 2 post office box 655303 ? dallas, texas 75265 terminal assignments 23 lineinr lineinl mic2 mic1 cdr cdgnd cdl videor videol auxr auxl phone 24 23 22 21 20 19 18 17 16 15 14 13 4 37 38 39 40 41 42 43 44 45 46 47 48 monoout av dd2 lnlvloutl mode1 lnlvloutr av ss2 gpio gpio cid0 cid1 eapd gpio 567 8 afilt1 vrefout vref av 35 34 33 32 31 36 30 lineoutr lineoutl cx3d2 cx3d1 cap2 sync resetb pcbeep xtlout sdataout bitclk ss2 sdatain dd2 28 27 26 29 9 10 11 12 25 1 av cap1 mode0 xtlin dd1 ss1 pfb package (top view) dv dv dv dv ss1 dd1 ordering information t a package t a 48-tqfp pfb 0 c to 70 c tlv320aic27cpfb 40 c to 85 c tlv320aic27ipfb
tlv320aic27 stereo audio codec slas253 march 2000 3 post office box 655303 ? dallas, texas 75265 functional block diagrametwo-channel mode vol/ mute vol/ mute vol/ mute vol/ mute vol/ mute vol/ mute (37) monoout (39,41) lnlvlout (35,36) lineout cd (18,20) linein (23,24) video (16,17) aux (14,15) phone (13) pcbeep (12) mic[1] (21) mic[2] (22) 0db/ 20db master/ slave select (45) cid[0] (46) cid[1] (6) bitclk (10) sync (8) sdatain (5) sdataout (11) resetb (47) eapd vol/ mute osc (2) xtlin (3) xtlout vol stereo dac src vol src vol/ mute mux vol/ mute vol/ mute mux key: mono stereo record mux and mute serial i/f 3d stereo dac
tlv320aic27 stereo audio codec slas253 march 2000 4 post office box 655303 ? dallas, texas 75265 functional block diagrame6-channel i 2 s, quad, and modem modes vol/ mute vol/ mute vol/ mute vol/ mute vol/ mute (37) monoout (39,41) lineout (35,36) lineout cd (18,20) linein (23,24) video (16,17) aux (14,15) phone (13) pcbeep (12) mic[1] (21) mic[2] (22) 0db/ 20db master/ slave select (45) cid[0] (46) cid[1] (6) bitclk (10) sync (8) sdatain (5) sdataout (11) resetb (47) eapd vol/ mute osc (2) xtlin (3) xtlout front stereo src vol src vol/ mute mux vol/ mute mux key: mono stereo record mux and mute serial i/f 3d stereo adc general (43,44,48) io supprt gpio[1:3] dac vol/ rear stereo src dac mute vol/ mute (30) mode0 (40) mode1 vol/ mute (rear) (front) rev. 2.1 switch vol/ mute vol/ mute vol/ mute
tlv320aic27 stereo audio codec slas253 march 2000 5 post office box 655303 ? dallas, texas 75265 terminal functions terminal type description name no. type description afilt1 29 analog output buffered cap2. this terminal has an internal connection. videol 16 analog input mixer input, typically for video signal videor 17 analog input mixer input, typically for video signal auxl 14 analog input mixer input, typically for aux signal auxr 15 analog input mixer input, typically for aux signal av dd1 25 supply analog positive supply av dd2 38 supply analog positive supply av ss1 26 supply analog ground supply, chip substrate av ss2 42 supply analog ground supply, chip substrate bitclk 6 digital output serial interface clock output to ac'97 controller cap1 31 analog output buffered cap2. this terminal has an internal connection. cap2 32 analog input reference input/output; pulls to midrail if not driven cdgnd 19 analog input cd input common-mode reference (ground) cdl 18 analog input mixer input, typically for cd signal cdr 20 analog input mixer input, typically for cd signal cid0 45 digital input master/slave id select (internal pullup) cid1 46 digital input master/slave id select (internal pullup) cx3d1 33 analog output output pin for 3d difference signal cx3d2 34 analog input input pin for 3d difference signal dv dd1 1 supply digital positive supply dv dd2 9 supply digital positive supply dv ss1 4 supply digital ground supply dv ss2 7 supply digital ground supply eapd 47 digital output external amplifier power down/gpo gpio 43, 44, 48 general-purpose i/o lineinl 23 analog input mixer input, typically for line signal lineinr 24 analog input mixer input, typically for line signal lineoutl 35 analog output main analog output for left channel lineoutr 36 analog output main analog output for right channel lnlvloutl 39 analog output left channel line-level output lnlvloutr 41 analog output right channel line-level output mic1 21 analog input mixer input with extra gain, if required mic2 22 analog input mixer input with extra gain, if required monoout 37 analog output main mono output mode0 30 digital input mode select pin, internal pulldown mode1 40 digital input mode select pin, internal pulldown pcbeep 12 analog input mixer input, typically for pcbeep signal phone 13 analog input mixer input, typically for phone signal resetb 11 digital input not reset input (active low, resets registers) sdatain 8 digital output serial-data output to ac'97 controller sdataout 5 digital input serial-data input sync 10 digital input serial-interface sync pulse from ac'97 controller vref 27 analog output buffered cap2. this terminal has an internal connection. vrefout 28 analog output reference for microphones; buffered cap2 xtlin 2 digital input clock-crystal connection or clock input (xtal not used) xtlout 3 digital output clock-crystal connection
tlv320aic27 stereo audio codec slas253 march 2000 6 post office box 655303 ? dallas, texas 75265 absolute maximum ratings over operating free-air temperature (unless otherwise noted) 2 digital supply voltage 0.3 v to 7 v . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . analog supply voltage 0.3 v to 7 v . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . voltage range digital inputs dv ss 0.3 v to dv dd +0.3 v . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . voltage range analog inputs av dd 0.3 v to av dd +0.3 v . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . operating temperature range, t a 0 c to 70 c . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . storage temperature 65 c to 150 c . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . lead temperature (soldering 10 seconds) 260 c . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . lead temperature (soldering 2 minutes) 183 c . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 stresses beyond those listed under aabsolute maximum ratingso may cause permanent damage to the device. these are stress rating s only, and functional operation of the device at these or any other conditions beyond those indicated under arecommended operating conditi onso is not implied. exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. recommended operating conditions min typ max unit digital supply range, dv dd 3.3 to 5 v analog supply range, av dd 3.3 to 5 v digital ground, dv ss 0 v analog ground, av ss 0 v analog supply current dv dd , av dd = 5 v 35 50 ma digital supply current dv dd , av dd = 5 v 30 50 ma standby supply current (all prs set) dv dd , av dd = 5 v 150 600 m a analog supply current dv dd , av dd = 3.3 v 22 33 ma digital supply current dv dd , av dd = 3.3 v 20 22 ma standby supply current (all prs set) dv dd , av dd = 3.3 v 100 150 m a
tlv320aic27 stereo audio codec slas253 march 2000 7 post office box 655303 ? dallas, texas 75265 electrical characteristics, av dd = 5 v, dv dd = 3.3 v, gnd = 0 v, t a = 0 c to 70 c (unless otherwise noted) parameter test conditions min typ max unit digital logic levels (dv dd = 3.3 v or 5 v) v il input low level av ss 0.3 0.8 v v ih input high level 2.2 av dd + 0.3 v v ol output low 0.1 dv dd v v oh output high 0.9 dv dd v analog i/o levels (input signals on any inputs, outputs on lineout l, r, and monoout) input level minimum input impedance = 10 k w av ss 100 mv av dd +100 mv v output level into 10 k w load av ss +100 mv near rail to rail av dd 100 mv v reference levels cap2 reference input/output 2/5 av dd av dd /2 3/5 av dd v cap2 impedance 75 k w vref mixer reference buffered cap2 v vrefout mic reference buffered cap2 v cap1 adc reference buffered cap2 v afilt1 dac reference buffered cap2 v vref current source (pins cap1, afilt2, vref and vrefout) av dd = 3 v 5 15 ma vref current source (pins cap1, afilt1, vref and vrefout) av dd = 5 v 3 5 ma dac circuit specifications (av dd = 5 v) 48-khz sampling snr a-weighted (see note 1) 85 95 db full-scale output voltage vref = 2.5 v 1 vrms thd 3-db full-scale input 74 96 db frequency response 20 19 200 hz transition band 19 200 28 800 hz stop band 28 800 hz out of band rejection 40 db spurious-tone reduction 100 db psrr 20 hz to 20 khz 40 db adc circuit specifications (av dd = 5 v) 48-khz sampling snr a-weighted (see note 1) 75 90 db adc input for full-scale output vref = 2.5 v 1 vrms thd 6-db voltage input 80 95 db frequency response 20 19 200 hz transition band 19 200 28 800 hz stop band 28 800 hz stop-band rejection 74 db psrr 20 hz to 20 khz 40 db note 1: snr is the ratio of 0-db signal output level to the output level with no signal, measured a-weighted over a 20 hz to 20 khz bandwidth.
tlv320aic27 stereo audio codec slas253 march 2000 8 post office box 655303 ? dallas, texas 75265 electrical characteristics, av dd = 5 v, dv dd = 3.3 v, gnd = 0 v, t a = 0 c to 70 c (unless otherwise noted) (continued) parameter test conditions min typ max unit mixer circuit specifications (av dd = 5 v) 48-khz sampling snr cd path a-weighted (see note 1) 90 95 db snr other paths a-weighted (see note 1) 85 95 db maximum input voltage av ss 1 av dd vrms maximum output voltage on lineout 1.0 1.8 vrms thd 0-db voltage input 74 90 db frequency response ( 1 db) 20 20000 hz input impedance (cd inputs) at any gain 15 k w in p ut im p edance (other mixer in p uts) at maximum gain 10 20 30 k w inp u t impedance (other mi x er inp u ts) at 0-db gain 50 100 150 k w in p ut im p edance mic in p uts at maximum gain 10 20 30 k w inp u t impedance mic inp u ts at 0-db gain 55 110 165 k w psrr 20 hz to 20khz 40 db dac circuit specifications (av dd = 3.3 v) 48-khz sampling snr a-weighted (see note 1) 96 db full scale output voltage vref = 1.65 v 0.7 vrms thd 3-db full-scale input 66 90 db frequency response 20 hz transition band 19200 19200 hz stop band 28800 28800 hz out-of-band rejection 40 db spurious-tone reduction 100 db psrr 20 hz to 20 khz 40 db adc-circuit specifications (av dd = 3.3 v) 48-khz sampling snr a-weighted (see note 1) 85 db adc input for full-scale output vref = 1.65 v 0.7 vrms thd 6-db voltage input 74 80 db frequency response 20 19200 hz transition band 19200 28800 hz stop band 28800 hz stop-band rejection 74 db psrr 20 hz to 20 khz 40 db note 1: snr is the ratio of 0-db signal output level to the output level with no signal, measured a-weighted over a 20 hz to 20 khz bandwidth.
tlv320aic27 stereo audio codec slas253 march 2000 9 post office box 655303 ? dallas, texas 75265 electrical characteristics, av dd = 5 v, dv dd = 3.3 v, gnd = 0 v, t a = 0 c to 70 c (unless otherwise noted) (continued) parameter test conditions min typ max unit mixer-circuit specifications (av dd = 3.3 v) 48 khz sampling snr cd path a-weighted (see note 1) 92 db snr other paths a-weighted (see note 1) 92 db maximum input voltage 0.66 vrms maximum output voltage on lineout 0.66 vrms thd 0-db voltage input 74 90 db frequency response ( 1 db) 20 20000 hz input impedance (cd inputs) at any gain 15 k w in p ut im p edance (other mixer in p uts) at maximum gain 20 k w inp u t impedance (other mi x er inp u ts) at 0-db gain 100 k w input impedance mic inputs at any gain 30 k w psrr 20 hz to 20 khz 40 db clock-frequency range crystal clock 24.576 mhz bit_clk frequency 12.288 mhz sync frequency 48.0 khz note 1: snr is the ratio of 0-db signal output level to the output level with no signal, measured a-weighted over a 20 hz to 20 khz bandwidth.
tlv320aic27 stereo audio codec slas253 march 2000 10 post office box 655303 ? dallas, texas 75265 detailed description 3d stereo enhancement this device contains a stereo-enhancement circuit, designed to optimize the listening experience when the device is used in a typical pc-operating environment (that is, with a pair of speakers placed either side of the monitor with little spatial separation). this circuit creates a differential signal by subtracting left and right channel playback data, then filters this difference signal using low-pass and high-pass filters whose time constants are set using external capacitors connected to the cx3d pins 33 and 34. typical values of 100 nf and 47 nf set high-pass and low-pass poles at about 100 hz and 1 khz respectively. this frequency band corresponds to the range over which the ear is most sensitive to directional effects. the filtered difference signal is gain-adjusted by an amount set using the four-bit value written to register 22h bits 3 to 0. value 0h is disabled, and value fh is maximum effect. a typical value of 8h is optimum. the user interface most typically uses a slider type of control to allow the user to adjust the level of enhancement to suit the program material. bit d13 3d in register 20h is the overall 3d-enable bit. the capability register 00h reads back the value 11000 in bits d14 to d10. this corresponds to decimal 24, which is registered with intel as texas instruments stereo enhancement. note that the external capacitors setting the filtering poles applied to the difference signal can be adjusted in value, or even replaced with a direct connection between the pins. when such adjustments are made, the amount of difference signal fed back into the main signal paths can be significant. this can cause large signals which may limit, distort, or overdrive signal paths or speakers. adjust these values carefully to select the desired acoustic effect. there is no provision for pseudo-stereo effects. mono signals have no enhancement applied if they are in phase and have the same amplitude. signals from the pcm dac channels do not have stereo enhancement applied. it is assumed that these signals have already been processed digitally with any required 3d-enhancement effect. applying the analog 3d-enhancement will corrupt the digital effect. this is equivalent to setting the pop bit in register 20h. as a result, the readback value of this bit is fixed as 1, and attempts to change it will be ignored. the pop bit is set to one and cannot be reset. variable sample rate support the dacs and adcs on this device support all the recommended sample rates specified in the intel revision 2.1 specification for both audio and modem rates. default rates are 48 ksps. if alternative rates are selected, the ac'97 interface continues to run at 48 kw/s (kilowords per second), but data is transferred across the link in bursts such that the net sample rate selected is achieved. it is up to the ac'97 revision 2.1-compliant controller to ensure that data is supplied to the ac link, and received from the ac link at the appropriate rate. the device supports on-demand sampling. that is, when the dac signal-processing circuits need another sample a request is sent to the controller, which must respond with a data sample in the next frame it sends. for example, if a rate of 24 ksps is selected, on average the device requests a sample from the controller every other frame, for each of the stereo dacs. note that if an unsupported rate is written to one of the rate registers, the rate defaults to the nearest rate supported. the register then responds when interrogated with the supported rate the device has defaulted to.
tlv320aic27 stereo audio codec slas253 march 2000 11 post office box 655303 ? dallas, texas 75265 variable sample rate support (continued) adcs are controlled similarly but with one difference: normally the left and right-channel adcs sample at the same rate. table 1. variable sample rates supported audio sample rate control value d15d0 modem sample rate control value d15d0 8000 1f40 7200 1c20 11025 2b11 8228.57 (57600/7) 2024 16000 3e80 8400 20d0 22050 5622 9000 2328 44100 ac44 9600 2580 48000 bb80 10285.71 (72000/7) 282d 12000 2ee0 13714.28 (96000/7) 3592 19200 4b00 24000 5dc0 table 2 shows which registers control which dac rates, versus mode and id selected. table 2. variable rate register location versus mode and id mode id front dac rate register rear dac rate register adc rate reg 00 and 01 2ch rev 2.1 mode (00) 10 2eh 32h 11 2ch (center) and 30h (lfe) 00 and 01 2ch rev 2.1 6-channel mode (01) 10 2eh 32h 11 2ch (center) and 30h (lfe) 00 and 01 2ch 2eh quad mode (10) 10 2eh 2ch 32h 11 2ch (center) and 30h (lfe) 2eh gain control register location versus mode and id depending on the operational mode and id of the device, the various gain control registers have locations in the register map that may change. for example, if the codec is configured as id 10, it means that the device will be converting the rear surround dac data. in this case, the surround dac volume word written to register 38h is now used to control the master volume control, rather than the normal master volume 02h. in addition, when the surround volume mute control is written as demute, mute in the dac pga register 18h is automatically overridden. then the user does not have to make an unexpected additional write to register 18h to demute the dac pga.
tlv320aic27 stereo audio codec slas253 march 2000 12 post office box 655303 ? dallas, texas 75265 gain control register location versus mode and id (continued) table 3. gain control register location versus mode and id pga codec id control reg rev 2.1 mode (0x) mute default quad mode (10) mute default modem mode (11) front dac pga 0x 10 11 18h muted (bit 15) and with 38h, 7, 15 and with 36h, 7, 15 muted (bit 15) and with 38h, 7, 15 and with 36h, 7, 15 muted (bit 15) and with 38h, 7, 15 and with 36h, 7, 15 rear dac pga 0x 10 11 70h muted (bit 15) and powered off not muted (bit 15) and with 02h, 15 and with 38h, 7, 15 and with 04h, 15 front mixer 0x 10 11 72h not muted (bit 15) not muted (bit 15) not muted (bit 15) rear mixer 0x 10 11 74h permanently muted not muted (bit 15) permanently muted front volume 0x 10 11 02h 38h 36h muted (bit 15) muted (7 and 15) muted (7 and 15) muted (bit 15) muted (7 and 15) muted (7 and 15) muted (bit 15) muted (7 and 15) muted (7 and 15) rear volume 0x 10 11 04h muted (bit 15) rev 2.1 switch enabled muted (7 and 15) muted (bit 15) muted (7 and 15) muted (bit 15) master/slave id0/1 support tlv320aic27 supports operation as either a master or a slave codec. configuring the device as master or slave is accomplished by tying together the cid pins cid0 and cid1 (pins 45 and 46 ). fundamentally, a device identified as a master (id = 00) produces bitclk as an output, whereas a slave (any id but 00) must be provided with bitclk as an input. the obvious implication is that if the master device on an ac link is disabled, the slave devices cannot function. the ac'97 revision 2.1 specification defines the cid pins as having inverting sense and being provided with internal weak pull ups. therefore, if no connections are made to the cid0/1 pins, then these pins pull hi and an id = 00 (or master) is selected. external connections to ground select other ids. table 4. id selection pin 45 cid0 pin 46 cid1 id selected master or slave bitclk nc nc 00 master output nc ground 01 slave input ground nc 10 slave input ground ground 11 slave input
tlv320aic27 stereo audio codec slas253 march 2000 13 post office box 655303 ? dallas, texas 75265 master/slave id0/1 support (continued) the tlv320aic27 supports the amap function, whereby selection of an id automatically maps the data from the interface onto the pcm dacs. table 5. default slot to dac mappings based on codec id ac-link frame data used for dacs codec id pcm left dac uses data from slot number pcm right dac uses data from slot number comments 00 3 4 original definition (master) 01 3 4 original definition (docking) 10 7 8 left/right surround channels 11 6 9 center/lfe channels the codec id is available to the controller via register 28h and c3, bits d15 and d14 the previous automatic mapping of data to slots is extended when the device is operated in the alternative modes selectable via the mode pins. in these cases the selection of which data slots are mapped onto internal dacs or i 2 s outputs is accomplished as shown in table 6. note that i 2 s enable bit must be set. table 6. slot to dac and mapping based on mode and codec id mode codec id slots mapped to front dacs slots mapped to rear dacs data to i 2 s d0 pin 44 data to i 2 s d1 pin 43 00 or 01 3 and 4 rev 2.1 (00) 10 7 and 8 not supported in this mode not supported in this mode not supported in this mode 11 6 and 9 r21 00 or 01 3 and 4 7 and 8 6 and 9 rev 2.1 6 - channel (01) 10 7 and 8 not supported in this mode 3 and 4 6 and 9 6 - channel (01) 11 6 and 9 7 and 8 3 and 4 00 or 01 3 and 4 7 and 8 7 and 8 6 and 9 quad (10) 10 7 and 8 3 and 4 3 and 4 6 and 9 11 6 and 9 7 and 8 7 and 8 3 and 4 00 or 01 3 and 4 modem (11) 10 7 and 8 5 (or 5 and 10 if dlm set) not supported in this mode not supported in this mode 11 6 and 9 slave codec register access definitions master codec access is exactly as defined for ac'97. for slave codec access, the ac'97 digital controller must invalidate the tag bits for slots 1 and 2 command address and data (slot 0, bits 14 and 13) and place a nonzero value (01, 10, or 11) into the codec id field (slot 0, bits 1 and 0). slave codecs disregard the command address and command data (slot 0, bits 14 and 13) tag bits when they see a two-bit codec id value (slot 0, bits 1 and 0) that matches their configuration. in a sense, the slave codec id field functions as an alternative valid command address (for slave reads and writes) and command data (for slave writes) tag indicator. slave codecs must monitor the frame valid bit and ignore the frame (regardless of the state of the slave codec id bits) when it is not valid. ac'97 digital controllers should set the frame valid bit for a frame with a slave register access, even if no other bits in the output tag slot, except the slave codec id bits, are set.
tlv320aic27 stereo audio codec slas253 march 2000 14 post office box 655303 ? dallas, texas 75265 slave codec register access definitions (continued) table 7. slave codec register access slot 0 bit definitions output tag slot (16 bits) bit description 15 frame valid 14 slot 1 valid command address bit (master codec only) 13 slot 2 valid command data bit (master codec only) 123 slot 312 valid bits as defined by ac'97 2 reserved (set to 0) 10 two-bit codec id field (00 reserved for master; 01, 10, 11 indicate slave) new definitions for slave codec register access control interface a digital interface is provided to control the tlv320aic27 and transfer data to and from it. this serial interface is compatible with the intel ac'97, as illustrated in figure 1. system information tlv320aic27 c54x /c6x or ac'97 compliant digital controller reset bitclk sync sdatain sdataout cid0 cid1 chip select pcbeep phone cd, video, aux, lineinl/r monoout lnlvloutl/r lineoutl/r mic2 mic1 37 41 39 36 13 12 21 22 11 6 10 8 5 45 46 35 figure 1. revision 2.1 compliant two-channel codec the main control interface functions are: control of analog gain and signal paths through the mixer bidirectional transfer of adc and dac words to and from ac'97 controller selection of power down modes
tlv320aic27 stereo audio codec slas253 march 2000 15 post office box 655303 ? dallas, texas 75265 system information (continued) sdataout bitclk sdatain sync reset tlv320aic27 front r data front l data lineoutl lineoutr id=00 sdataout bitclk sdatain sync reset surround r data surround l data lineoutl lineoutr id=10 sdataout bitclk sdatain sync reset xtlout xtlin c54xx/c6x mcbsp o r ac'97 compliant digital controller tlv320aic27 figure 2. tlv320aic27 in a four-channel system
tlv320aic27 stereo audio codec slas253 march 2000 16 post office box 655303 ? dallas, texas 75265 system information (continued) sdataout bitclk sdatain sync reset tlv320aic27 lineoutl lineoutr id=00 sdataout bitclk sdatain sync reset lineoutl lineoutr id=10 sdataout bitclk sdatain sync reset lineoutl lineoutr id=11 sdataout bitclk sdatain sync reset xtlout xtlin xtlin c54xx c6x mcbsp or ac'97 compliant digital controller tlv320aic27 tlv320aic27 front r data front l data surround r data surround l data center data lfe data figure 3. tlv320aic27 in a six-channel system
tlv320aic27 stereo audio codec slas253 march 2000 17 post office box 655303 ? dallas, texas 75265 system information (continued) aic27 reset bitclk sync sdatain sdataout cid0 cid1 chip select pcbeep phone cd, video, aux, lineinl/r monoout lnlvloutl/r lineoutl/r mic2 mic1 37 41 39 36 13 12 21 22 11 6 10 8 5 45 46 35 front data rear data external dac surround sound (center and lfe data) optional for ac-3 type surround sound (5.1) i 2 s data lrclk bitclk sclk 48 [1:3] 43 gpio (quad mode) c54x /c6x or ac'97 compliant digital controller figure 4. aic27 in typical quad-mode application
tlv320aic27 stereo audio codec slas253 march 2000 18 post office box 655303 ? dallas, texas 75265 system information (continued) aic27 reset bitclk sync sdatain sdataout cid0 cid1 chip select pcbeep phone cd, video, aux, lineinl/r monoout lnlvl_out_l/r line_out_l/r mic2 mic1 37 13 39, 41 36 13 12 21 22 11 6 10 8 5 45 46 35 front data daa tx rx gpio [1:3] 48 44 43 xtal 23 mode0 = 1 mode1 = 1 (modem mode) phone modem data c54x /c6x or ac'97 compliant digital controller figure 5. aic27 in a typical modem application
tlv320aic27 stereo audio codec slas253 march 2000 19 post office box 655303 ? dallas, texas 75265 ac-link digital serial interface protocol the tlv320aic27 incorporates a five-pin digital serial interface that links it to the ac'97 controller. the ac link is a bidirectional, fixed rate, serial pcm digital stream. it handles multiple input and output audio streams, as well as control register-accesses employing a time-division multiplexed (tdm) scheme. the ac-link architecture divides each audio frame into 12 outgoing and 12 incoming data streams, each with 20-bit sample resolution. with a minimum required resolution of 16-bits for the dac and the adc, ac'97 can also be implemented with 18 or 20-bit dac/adc resolution, given the headroom that the ac-link architecture provides. the tlv320aic27 provides support for 18-bit operation. slot number sync sdata_out sdata_in tag phase tag cmd adr cmd data pcm left pcm right rsrvd pcm lfe rsrvd rsrvd tag status addr status data pcm left pcm right rsrvd rsrvd rsrvd rsrvd rsrvd rsrvd rsrvd gpio status 0123456789101112 pcm center pcm l surr pcm r surr gpio ctrl pcm c (n+1) pcm r (n+1) pcm l (n+1) codec id slotreq 312 data phase figure 6. ac'97 standard bidirectional audio frame basic mode (two-channel) slot number sync sdata_out sdata_in tag phase tag cmd adr cmd data pcm left pcm right line 1 pcm lfe rsrvd tag status addr status data pcm left pcm right rsrvd rsrvd rsrvd rsrvd rsrvd gpio status 0123456789101112 pcm center pcm l surr pcm r surr gpio ctrl pcm c (n+1) pcm r (n+1) pcm l (n+1) codec id slotreq 312 data phase dac line 1 dac line 2 dac line 2 dac figure 7. ac'97 standard bidirectional audio frame modem mode
tlv320aic27 stereo audio codec slas253 march 2000 20 post office box 655303 ? dallas, texas 75265 ac-link digital serial interface protocol (continued) slot number sync sdata_in tag cmd adr cmd data pcm left pcm right line 1 pcm lfe hset tag status addr status data pcm left pcm right mic rsrvd rsrvd rsrvd io status 0123456789101112 pcm center pcm l surr pcm r surr io ctrl pcm c (n+1) pcm r (n+1) pcm l (n+1) codec id slotreq 312 dac line 2 dac dac line 1 dac adc hset line 2 adc adc figure 8. ac'97 standard bidirectional audio frame in quad mode sync bit_clk sdata_out valid frame slot(1) slot(2) slot(12) '0' '0' '0' 19 0 19 0 19 0 19 0 12.288 mhz 81.4 ns end of previous audio frame time slot 'valid' bits ('1' = time slot contains valid pcm data) slot (1) slot (2) slot (3) slot (12) data phase tag phase 20.8 m s (48 khz) figure 9. ac-link serial interface protocol output frame the data streams currently defined by the ac'97 specification include: pcm playbacketwo output slots two-channel composite pcm output stream pcm record dataetwo input slots two-channel composite pcm input stream controletwo output slots control register write port statusetwo input slots control register read port optional dedicated microphone inputeone input slot dedicated microphone input stream in support of stereo aec and/or other voice applications optional modem line codec outputeone output slot modem line codec dac input stream optional modem line codec inputeone input slot modem line codec adc output stream the tlv320aic27 controller signals synchronization of all ac-link data transactions. the tlv320aic27 drives the serial bit clock onto the ac link, which the ac'97 controller then qualifies with a synchronization signal to construct audio frames. sync, fixed at 48 khz, is derived by dividing down the serial clock (bit_clk). bit_clk, fixed at 12.288 mhz, provides the necessary clocking granularity to support 12 20-bit outgoing and incoming time slots. ac-link serial data transition occurs on each rising edge of bit_clk. the receiver of ac-link data (tlv320aic27 for outgoing data and ac'97 controller for incoming data) samples each serial bit on the falling edges of bit_clk.
tlv320aic27 stereo audio codec slas253 march 2000 21 post office box 655303 ? dallas, texas 75265 ac-link digital serial interface protocol (continued) the ac-link protocol provides for a special 16-bit time slot (slot 0) wherein each bit conveys a valid tag for its corresponding time slot within the current audio frame. a 1 in a given bit position of slot 0 indicates that the corresponding time slot within the current audio frame has been assigned to a data stream and contains valid data. if a slot is tagged invalid, it is the responsibility of the data source (the tlv320aic27 for the input stream and the ac'97 controller for the output stream) to fill all bit positions with 0s during that slot's active time. sync remains high for a total duration of 16 bit_clks at the beginning of each audio frame. the portion of the audio frame where sync is high is defined as the tag phase. the remainder of the audio frame where sync is low is defined as the data phase. additionally, all clock, sync, and data signals can be halted to save power. this requires that the tlv320aic27 be implemented as a static design to allow its register contents to remain intact when entering a power savings mode. ac-link audio output frame (sdata_out) the audio output frame data streams correspond to the multiplexed bundles of all digital output data targeting the tlv320aic27's dac inputs and control registers. as mentioned earlier, each audio output frame supports up to 12 20-bit outgoing data time slots. slot 0 is a reserved time slot containing 16-bits, which are used for ac-link protocol infrastructure. the first bit within slot 0 is a global bit (sdata_out slot 0, bit 15) which flags the validity for the entire audio frame. a valid frame bit equal to 1 indicates that the current audio frame contains at least one time slot of valid data. the next 12-bit positions sampled by the tlv320aic27 indicate which of the corresponding 12 time slots contain valid data. in this way, data streams of differing sample rates can be transmitted across the ac link at its fixed 48-khz audio frame rate. figure 9 illustrates the time-slot-based ac-link protocol. sync bit_clk sdata_out valid frame slot (1) slot (2) sync assertion here aic27 samples first sdata_out bit of frame here end of previous audio frame aic27 samples figure 10. start of an audio output frame a new audio output frame begins with a low-to-high transition of sync, as shown in figure 10. sync is synchronized to the rising edge of bit_clk. on the falling edge of bit_clk immediately following, the tlv320aic27 samples the assertion of sync. this falling edge marks the time when both sides of the ac link are aware of the start of a new audio frame. on the next rising edge of bit_clk, ac'97 transitions sdata_out into the first bit position of slot 0 (valid frame bit). each new bit position is presented to the ac link on a rising edge of bit_clk, and subsequently sampled by the tlv320aic27 on the following falling edge of bit_clk. this sequence ensures that data transitions and subsequent sample points for both incoming and outgoing data streams are time-aligned.
tlv320aic27 stereo audio codec slas253 march 2000 22 post office box 655303 ? dallas, texas 75265 ac-link audio output frame (sdata_out) (continued) baseline ac'97-specified audio functionality should always convert the sample rate to and from a fixed 48 ksps on the ac'97 controller. this requirement ensures that interoperability between the ac'97 controller and the tlv320aic27, among other things, can be assured by definition for baseline specified ac'97 features. sdata_out's composite stream is msb justified (msb first), with all invalid slot bit positions stuffed with 0s by the ac'97 controller. in the event that there are less than 20 valid bits within an assigned and valid time slot, the ac'97 controller always stuffs all trailing invalid bit positions of the 20-bit slot with 0s. as an example, consider an eight-bit sample stream that is being played out to one of the tlv320aic27's dacs. the first eight-bit positions are presented to the dac (msb justified), followed by the next 12-bit positions, which are stuffed with 0s by the ac'97 controller. this ensures that, regardless of the resolution of the implemented dac (16, 18, or 20-bit), no dc biasing is introduced by the least significant bits. when mono audio sample streams are outputted from the ac'97 controller, it is necessary that both left and right sample-stream time slots be filled with the same data. slot 1: command address port the command port is used to control features and monitor status for the tlv320aic27 functions including, but not limited to, mixer settings and power management (refer to the serial interface register map). the control interface architecture supports up to 64 16-bit read/write registers, addressable on even-byte boundaries. only the even registers (00h, 02h, etc.) are valid. access to odd registers (01h, 03h, etc.) is discouraged (if supported, they should default to the preceding even-byte boundaryethat is, a read from 01h returns the 16-bit contents of 00h). the tlv320aic27's control register file is nonetheless readable as well as writeable to provide more robust testability. audio output frame slot 1 communicates control register address and read/write command information to the tlv320aic27. command address port bit assignments bit (19) read/write command (1 = read, 0 = write) bit (18:12) control register index (64 16-bit locations, addressed on even byte boundaries) bit (11:0) reserved (stuffed with 0s) the first bit (msb) sampled by the tlv320aic27 indicates whether the current control transaction is a read or a write operation. the following seven bit positions communicate the targeted control register address. the trailing 12 bit positions within the slot are reserved and must be stuffed with 0s by the ac'97 controller. slot 2: command data port the command data port is used to deliver 16-bit control register write data in the event that the current command port operation is a write cycle, as indicated by slot 1, bit 19. bit (19:4) control register write data (stuffed with 0s if current operation is a read) bit (3:0) reserved (stuffed with 0s) if the current command port operation is a read, then the entire time slot must be stuffed with 0s by the ac'97 controller. slot 3: pcm playback left channel audio output frame slot 3 is the composite digital audio left playback stream. in a typical games compatible pc, this slot is composed of standard pcm (.wav) output samples digitally mixed (in the ac'97 controller or host processor) with music synthesis output samples. if a sample stream with less than 20 bits of resolution is transferred, the ac'97 controller must stuff all trailing invalid bit positions within this time slot with 0s.
tlv320aic27 stereo audio codec slas253 march 2000 23 post office box 655303 ? dallas, texas 75265 ac-link audio output frame (sdata_out) (continued) slot 4: pcm playback right channel audio output frame slot 4 is the composite digital audio right-playback stream. in a typical games-compatible pc, this slot is composed of standard pcm (.wav) output samples digitally mixed (on the ac'97 controller or host processor) with music synthesis output samples. if a sample stream with less than 20 bits of resolution is transferred, the ac'97 controller must stuff all trailing invalid bit positions within this time slot with 0s. slot 5: optional modem line1 codec audio output frame slot 5 contains the msb-justified modem line1 dac input data. this optional ac'97 feature is supported in the tlv320aic27, but only in the modem-operation mode (selected with the mode0/1 pins). when data is written to this location, it is applied to the rear channel dacs if the modem mode is enabled. this is determined by the ac'97 controller interrogating the tlv320aic27 vendor id registers. if modem mode is disabled, the device appears not to support a modem. if the mode is enabled, the modem support flag is set. slot 6 to 9: surround sound data audio output frame slots 6 to 9 are used to send surround-sound data to the extra dac channels. these slots are supported by tlv320aic27 in revision 2.1 six-channel mode and quad mode. note that the data in the surround-sound slots may be applied to the internal dacs, or sent out onto the gpio pins as i 2 s data, depending upon the mode and id selected. slot 10 optional modem line2 codec audio output frame slot 10 contains msb-justified modem line2 dac input data. this optional ac'97 feature is supported by tlv320aic27, but only when register 5ah dlm (dual line modem) is set. slot 11 handset dac slot 11 is not supported. slot 12: gpio control data in this slot is applied to the gpio pins if they have been enabled via the control registers. note that only bits 11, 12, and 13 are supported and all others are ignored. ac-link audio input frame (sdata_in) sync bit_clk sdata_in codec ready slot(1) slot(2) slot(12) '0' '0' '0' 19 0 19 0 19 0 19 0 12.288 mhz 81.4 ns end of previous audio frame time slot 'valid' bits ('1' = time slot contains valid pcm data) slot (1) slot (2) slot (3) slot (12) data phase tag phase 20.8 m s (48 khz) figure 11. ac-link audio input frame
tlv320aic27 stereo audio codec slas253 march 2000 24 post office box 655303 ? dallas, texas 75265 ac-link audio input frame (sdata_in) (continued) the audio input frame data streams correspond to the multiplexed bundles of all digital input data targeting the ac'97 controller. as in the case of audio output frame, each ac-link audio input frame consists of 12 20-bit time slots. slot 0 is a specially reserved time slot containing 16 bits, which are used for ac-link protocol infrastructure. the first bit in slot 0 is a global bit (sdata_in, bit 15) which flags whether the tlv320aic27 is in the codec-ready state or not. a codec-ready bit equal to 0 indicates that the tlv320aic27 is not ready for normal operation. for example, this is a normal condition following reset, while the tlv320aic27's voltage references settle. an ac-link codec-ready indicator bit equal to 1 indicates that the ac link and the tlv320aic27 control and status registers are in fully-operational state. the ac'97 controller must further probe the power-down control/status register to determine exactly which subsections, if any, are ready. prior to any attempts at putting the tlv320aic27 into operation, the ac'97 controller should poll the first bit in the audio input frame (sdata_in slot 0, bit 15) for an indication that the tlv320aic27 is codec-ready. once the tlv320aic27 is codec-ready, the next 12 bit positions sampled by the ac'97 controller indicate which of the corresponding 12 time slots are assigned to input data streams and contain valid data. figure 11 illustrates the time-slot-based ac-link protocol. there are several subsections within the tlv320aic27 that can independently go busy/ready. it is the responsibility of the tlv320aic27 controller to probe more deeply into the tlv320aic27 register file to determine which of the tlv320aic27 subsections are actually ready. sync bit_clk sdata_in codec ready slot (1) slot (2) aic27 samples sync assertion here ac '97 controller samples first sdata_in bit of frame here end of previous audio frame figure 12. start of an audio input frame a new audio input frame begins with a low-to-high transition of sync, as illustrated in figure 12. sync is synchronous with the rising edge of bit_clk. the tlv320aic27 samples the assertion of sync on the next falling edge of bit_clk. this falling edge marks the time when both sides of the ac link are aware of the start of a new audio frame. the ac'97 controller transitions sdata_in into the first bit position of slot 0 (valid frame bit) on the next rising edge of bit_clk. each new bit position is presented to the ac link on a rising edge of bit_clk, and subsequently sampled by the ac'97 controller on the following falling edge of bit_clk. this sequence ensures that data transitions and subsequent sample points for both incoming and outgoing data streams are time-aligned.
tlv320aic27 stereo audio codec slas253 march 2000 25 post office box 655303 ? dallas, texas 75265 ac-link audio input frame (sdata_in) (continued) sdata_in's composite stream is msb-justified (msb first), with all invalid bit positions (for assigned and/or unassigned time slots) stuffed with 0's by the tlv320aic27. sdata_in is sampled on the falling edges of bit_clk. slot 1: status address port the status port is used to monitor the status of the tlv320aic27 functions,, including, but not limited to, mixer settings and power management. audio input frame slot 1 echoes the control register index, for historical reference, so that the data is returned to slot 2 (assuming that slots 1 and 2 had been tagged valid by the tlv320aic27 during slot 0). status address port bit assignments bit (19) reserved (stuffed with 0s) bit (18:12) control register index (echo of register index for which data is being returned) bit (11:0) reserved (stuffed with 0s) the first bit (msb) generated by the tlv320aic27 is always stuffed with a 0. the following 7 bit positions communicate the associated control register address, and the trailing 12 bit positions are stuffed with 0s by the tlv320aic27. slot 2: status data port the status data port delivers 16-bit control register read data. bit (19:4) control register read data bit (3:0) reserved (stuffed with 0s) if slot 2 is tagged invalid by the tlv320aic27, then the entire slot is stuffed with 0s by the tlv320aic27. slot 3: pcm record left channel audio input frame slot 3 is the left channel output of the tlv320aic27's input mux, post-adc. the tlv320aic27's adcs can be implemented to support 16, 18, or 20-bit resolutions. the tlv320aic27 sends out its adc output data (msb first), and stuffs any trailing invalid bit positions with 0s to fill out its 20-bit time slot. slot 4: pcm record right channel audio input frame slot 4 is the right channel output of the tlv320aic27's input mux, post-adc. the tlv320aic27's adcs can be implemented to support 16, 18, or 20-bit resolutions. the tlv320aic27 sends out its adc output data (msb first), and stuffs any trailing invalid bit positions with 0s to fill out its 20-bit time slot. slot 5: optional modem line1 codec slot 5 is not supported. slot 6: optional dedicated microphone record data audio input frame slot 6 is an optional (post-adc) third pcm system input channel available for dedicated use by a desktop microphone. this optional ac'97 feature is not supported by the tlv320aic27. this can be determined by the ac'97 controller interrogating the tlv320aic27 vendor id register. slot 7 to 11: reserved audio input frame slots 7 to 12 are reserved for future use and are always stuffed with 0s by the tlv320aic27. slot 10: optional modem line2 codec slot 10 is not supported.
tlv320aic27 stereo audio codec slas253 march 2000 26 post office box 655303 ? dallas, texas 75265 ac-link audio input frame (sdata_in) (continued) slot 12: gpio functions supported. ac-link low-power mode the ac-link signals can be placed in a low-power mode. when the tlv320aic27's power-down register 26h is programmed to the appropriate value, both bit_clk and sdata_in are brought to and held at a logic-low voltage level. bit_clk and sdata_in transition to low occurs immediately following the decode of the write to the power-down register 26h with pr4. when the ac'97 controller driver is ready to program the ac link into its low-power mode, slots 1 and 2 are assumed to be the only valid stream in the audio output frame. at this point it is assumed that all sources of audio input have also been neutralized. the ac'97 controller should also drive sync and sdata_out low after programming the tlv320aic27 to this low-power, halted mode. once the tlv320aic27 has been instructed to halt bit_clk, a special wake up protocol must be used to bring the ac link to the active mode, since normal audio output and input frames can not be communicated in the absence of bit_clk. waking up the ac link there are two methods to bring the ac link out of a low-power, halted mode. regardless of the method, it is the ac'97 controller that performs the wake-up task. ac-link protocol provides for a cold and a warm tlv320aic27 reset. the current power-down state would ultimately dictate which form of tlv320aic27 reset is appropriate. unless a cold or register reset (a write to the reset register) is performed, wherein the tlv320aic27 registers are initialized to their default values, registers are required to keep state during all power-down modes. once powered down, reactivation of the ac link via reassertion of the sync signal must not occur for a minimum of four audio frame times following the frame in which the power down was triggered. when the ac link powers up, it indicates readiness via the codec-ready bit (input slot 0, bit 15). cold tlv320aic27 reset a cold reset is achieved by asserting resetb for the minimum specified time. by driving resetb low, bit_clk, and sdata_out are activated, or reactivated as the case may be, and all the tlv320aic27 control registers are initialized to their default power on reset values. resetb is an asynchronous tlv320aic27 input. warm tlv320aic27 reset a warm tlv320aic27 reset reactivates the ac link without altering the current tlv320aic27 register values. a warm reset is signalled by driving sync high for a minimum of 1 m s in the absence of bit_clk. within normal audio frames, sync is synchronous to the tlv320aic27 input. however, in the absence of bit_clk, sync is treated as an asynchronous input used in the generation of a warm reset to the tlv320aic27. the tlv320aic27 does not respond to the activation of bit_clk until sync has been sampled low again by the tlv320aic27. this precludes the false detection of a new audio frame.
tlv320aic27 stereo audio codec slas253 march 2000 27 post office box 655303 ? dallas, texas 75265 serial interface register map description (see table 23) the serial interface bits perform control functions described as follows (notice that the register map is fully specified by the ac'97 specification, and this description is simply repeated below, with optional unsupported features omitted): reset register (index 00h) writing any value to this register performs a register reset, which causes all registers to revert to their default values. reading this register returns the id code of the part to indicate modem support (not supported by the tlv320aic27) and a code for the type of 3d stereo enhancement. the id decodes the capabilities of the tlv320aic27 based on the information in table 8. table 8. reset register function bit function value on tlv320aic27 id0 dedicated mic pcm in channel 0 id1 modem line codec support 0 id2 bass and treble control 0 id3 simulated stereo (mono to stereo) 0 id4 headphone out support 0 id5 loudness (bass boost) support 0 id6 18-bit dac resolution 1 id7 20-bit dac resolution 0 id8 18-bit adc resolution 1 id9 20-bit adc resolution 0 se4...se0 3d-stereo enhancement technique 11000 note that the tlv320aic27 defaults to indicate 18-bit compatibility. however, a control bit can be set in the vendor-specific registers that changes bits id6 and id8 to be 0, indicating a 16-bit device. however, it is unlikely that this function will be required, as the msb justification of the adc and dac data means that a nominal 18-bit device should be fully compatible with controllers that only provide 16-bit support. most pc-type applications only require 16-bit operation. play master volume registers (index 02h, 04h and 06h) these registers manage the output signal volumes. register 02h controls the stereo master volume (both right and left channels), register 04h controls the optional stereo headphone out, and register 06h controls the mono volume output. each step corresponds to 1.5 db. the msb of the register is the mute bit. when this bit is set to 1, the level for that channel is set to db. ml5 to ml0 are used for left channel level, mr5 to mr0 are used for right channel level, and mm5 to mm0 are used for mono-out channel level. support for the msb of the volume level is not provided by the tlv320aic27. if the msb is written to, then the tlv320aic27 detects when that bit is set and sets all four lsbs to 1s. for example, if the driver writes a 1xxxxx, the tlv320aic27 interprets that as x1 1111. it also responds when read with x1 1111 rather than 1xxxxx, the value written to it. the driver can use this feature to detect if there is support for the 6th bit.
tlv320aic27 stereo audio codec slas253 march 2000 28 post office box 655303 ? dallas, texas 75265 play master volume registers (index 02h, 04h and 06h) (continued) the default value of both the mono and the stereo registers is 8000h (1000 0000 0000 0000), which corresponds to 0-db gain with mute on. table 9. volume register function mute mx4...mx0 function 0 0 0000 0-db attenuation 0 0 0001 1.5-db attenuation 0 1 1111 46.5-db attenuation 1 x xxxx -db attenuation master tone control register (index 08h) this is an optional register for support of tone controls (bass and treble). the tlv320aic27 does not support bass and treble, and writing to this register has no effect. reading results in all don't care values. pc beep register (index 0ah) this register controls the level of the pc-beep input. each step corresponds to approximately 3 db of attenuation. the register's msb is the mute bit. when this bit is set to 1, the level for that channel is set to db. the tlv320aic27 defaults to the pc-beep path being muted, so an external speaker should be provided within the pc to alert the user when power on self-test problems occur. table 10. pc-beep register function mute pv3...pv0 function 0 0000 0-db attenuation 0 1111 45-db attenuation 1 xxxx -db attenuation analog mixer input gain registers (index 0ch18h) these registers control the gain/attenuation of each of the analog inputs. each step corresponds to approximately 1.5 db. the msb of the register is the mute bit. when this bit is set to 1, the level for that channel is set to db (see table 11). register 0eh (mic volume register) this register has an extra bit used for a 20-db boost. when bit 6 is set to 1, the 20-db boost is on. the default value is 8008h, which corresponds to 0-db gain with mute on. the default value for the mono registers is 8008h, which corresponds to 0-db gain with mute on. the default value for stereo registers is 8808h, which corresponds to 0-db gain with mute on. table 11. mixer gain control register function mute gx4...gx0 function 0 00000 12-db gain 0 01001 0-db gain 0 11111 34.5-db gain 1 xxxxx -db gain
tlv320aic27 stereo audio codec slas253 march 2000 29 post office box 655303 ? dallas, texas 75265 record select control register (index 1ah) this register is used to select the record source for right and left independently (see table 12). the default value is 0000h, which corresponds to mic in. table 12. record select register function sr2 to sr0 right record source sl2 to sl0 left record source 0 mic 0 mic 1 cd in (r) 1 cd in (l) 2 video in (r) 2 video in (l) 3 aux in (r) 3 aux in (l) 4 line in (r) 4 line in (l) 5 stereo mix (r) 5 stereo mix (l) 6 mono mix 6 mono mix 7 phone 7 phone record gain registers (index 1ch and 1eh) 1ch is for the stereo input and 1eh is for the optional special-purpose correlated audio mic channel. each step corresponds to 1.5 db. 22.5 db corresponds to the range 0f0fh to 000fh. the msb of the register is the mute bit. when this bit is set to 1, the level for that channel(s) is set to db. the default value is 8000h, which corresponds to 0-db gain with mute on. table 13. record gain register function mute gx3...gx0 function 0 1111 22.5-db gain 0 0000 0-db gain 1 xxxxx -db gain general-purpose register (index 20h) this register is used to control several miscellaneous functions of the tlv320aic27. table 14 shows a summary of each bit and its function. only the mix, ms, and lpbk bits are supported by the tlv320aic27. the ms bit controls the mic selector. the lpbk bit enables loopback of the adc output to the dac input without involving the ac link, allowing for full system-performance measurements. the function default value is 0000h which is all off. table 14. general purpose register function bit function tlv320aic27 support pop pcm out path and mute, 0 = pre-3d, 1 = post-3d yes, but fixed at 1 st simulated stereo enhancement on/off, 1 = on no 3d 3d stereo enhancement on/off, 1 = on yes ld loudness (bass boost) on/off, 1 = on no llbk local loop backefor modem, line codec no rlbk remote loop backefor modem, line codec no mix mono output select 0 = mix, 1 = mic yes ms mic select 0 = mic1, 1 = mic2 yes lpbk adc/dac/ loopback mode yes
tlv320aic27 stereo audio codec slas253 march 2000 30 post office box 655303 ? dallas, texas 75265 3d control register (index 22h) this register is used to control the center and/or depth of the 3d stereo-enhancement function built into the ac'97 component. only the depth bits, dp03 have effect in the tlv320aic27. dp3...dp0 depth 0 0% 1 8 typical value 15 100% reserved register (index 24h) not supported by the tlv320aic27. power-down control/status register (index 26h) this read/write register is used to program the power-down states and to monitor subsystem readiness. the lower half of this register is read-only status, a 1 indicating that the subsection is ready . ready is defined as the subsection being able to perform in its nominal state. when this register is written, the bit values that come in on the ac link have no effect on read only bits 0 to 7. an ac-link codec-ready indicator bit (sdata_in slot 0, bit 15) equal to 1 it indicates that the ac link and the tlv320aic27 control and status registers are in a fully operational state. the ac'97 controller must further probe this power-down control/status register to determine exactly which subsections, if any, are ready. table 15. power-down status register function read bit function ref vrefs up to nominal level anl analog mixers, etc., ready dac dac section ready to accept data adc adc section ready to transmit data the power-down modes are as follows. the first three bits are to be used individually rather than in combination with each other. the last bit pr3 can be used in combination with pr2 or by itself. pr0 and pr1 control the pcm adcs and dacs only. pr6 is not supported by the tlv320aic27. table 16. power-down control register function write bit function pr0 pcm in adcs and input mux power down pr1 pcm out dacs power down pr2 analog mixer power down (vref still on) pr3 analog mixer power down (vref off) pr4 digital interface (ac link) power down (external clock off) pr5 internal clock disable pr6 hp amp power down not supported eapd external amplifier power down
tlv320aic27 stereo audio codec slas253 march 2000 31 post office box 655303 ? dallas, texas 75265 power-down control/status register (index 26h) (continued) pr0 = 1 pr1 = 1 pr2 = 1 pr4 = 1 pr0 = 0 and adc = 1 default ready = 1 cold reset warm reset pr2 = 0 and anl = 1 pr1 = 0 and dac = 1 adcs off pr0 dacs off pr1 analogue off pr2 or pr3 digital i/f off pr4 shut off coda link normal figure 13. an example of the tlv320aic27 power-down/power-up flow figure 13 illustrates one example of a procedure to perform a complete power down of the tlv320aic27. from normal operation, sequential writes to the power-down register are performed to power down the tlv320aic27 one piece at a time. after everything has been shut off (pr0 to pr3 set), a final write (of pr4) can be executed to shut down the tlv320aic27's digital interface (ac link). the part remains in sleep mode with all its registers holding their static values. to wake up the tlv320aic27, the ac'97 controller sends a pulse on the sync line issuing a warm reset. this restarts the tlv320aic27's digital interface (resetting pr4 to 0). the tlv320aic27 can also be woken up with a cold reset. a cold reset causes a loss of values to the registers, as it sets them to their default states. when a section is powered back on, the power-down control/status register index 26h should be read to verify that the section is ready (that is, stable) before attempting any operation that requires it. alternatively, if resetb is held low, all pr bits are held set so the device stays powered off until resetb is taken high again.
tlv320aic27 stereo audio codec slas253 march 2000 32 post office box 655303 ? dallas, texas 75265 power-down control/status register (index 26h) (continued) pr0 = 1 pr1 = 1 pr2 = 1 pr4 = 1 pr0 = 0 and adc = 1 default ready = 1 cold reset warm reset pr2 = 0 and anl = 1 pr1 = 0 and dac = 1 adcs off pr0 dacs off pr1 analog off pr2 or pr3 digital i/f off pr4 shut off coda link normal figure 14. the tlv320aic27 power-down/flow with analog still alive figure 14 illustrates a state where all the mixers should work with the static volume settings contained in their associated registers. this is used when the user is playing a cd (or external linein source) through the tlv320aic27 to the speakers, but has most of the system in low-power mode. the procedure for this follows the previous procedure, except that the analog mixer is never shut down. note that pr5 is required to be set in order to go into ultimate low-power mode, which turns off the oscillator circuit. asserting sync resets the pr5 bit and restarts the oscillator in the same way as the ac link is restarted. also, when resetb pin is asserted low, all pr bits are overridden and the entire device is powered off to ultralow-power state for as long as resetb = low. when resetb is released the device is reset (all active) and powered up. vendor-reserved registers (index 5ah to 7ah) these vendor-specific registers are reserved for future use. do not write to these registers unless the vendor id register has been checked first to ensure that the driver knows the source of the ac'97 component. values stored in this register are intended to provide test modes for use by the manufacturer. revision 2.1 registers (index 28h to 58h) the use of these registers is specified in revision 2.1 of the ac'97 specification and have the following functions on the tlv320aic27: register 28h extended audio id the extended audio id register is a read-only register that identifies which extended audio features are supported (in addition to the original ac'97 features identified by reading the reset register at index 00h). a nonzero value indicates the feature is supported. the indication of support for six-channel surround sound changes depending on whether the tlv320aic27 is configured in mode 00 or otherwise.
tlv320aic27 stereo audio codec slas253 march 2000 33 post office box 655303 ? dallas, texas 75265 register 28h extended audio id (continued) table 17. extended audio id register data bit function any mode but 10 mode 10 vra variable rate audio support 1 1 dra double rate audio support 0 0 vrm variable rate mic adc support 0 0 cdac center dac support 0 (unless i 2 s = 1) 1 when id = 11 or i 2 s = 1 sdac surround dac support 0 (unless i 2 s = 1) 1 ldac lfe dac support 0 (unless i 2 s = 1) 1 when id = 11 or i 2 s = 1 amap slot to front dac mapping support 1 1 id1 codec configuration pin 45 value inverse of level at pin 45 inverse of level at pin 45 id0 codec configuration pin 46 value inverse of level at pin 46 inverse of level at pin 46 register 2ah extended audio status and control register the extended audio status and control register is a read/write register that provides status and control of the extended audio features. table 18. extended audio status and control register data bit function read/write tlv320aic27 support vra enables variable rate audio mode read/write yes dra enable double rate audio mode read/write no vrm enables variable rate mic adc read/write no cdac indicates center dac ready read yes sdac indicates surround dac ready read yes ldac indicates lfe dac ready read yes madc indicates mic adc ready read no pri set to turn off center dac read/write enable only prj set to turn off surround dacs read/write enable only prk set to turn off lfe dacs read/write enable only prl set to turn off mic adc read/write no register 2ch to 32h audio sample rate control registers these registers are read/write registersewriting to this registers is done to select alternative sample rates for the audio pcm converters. the default rate is 48 ksps. note that only revision 2.1-recommended rates are supported by the tlv320aic27; selection of any other unsupported rates causes the rate to default to the nearest supported rate, and the supported rate value to be latched and therefore, read back. register 2ch is the front dac rate register, but it is also used for center channel data rate. i 2 s mode only supports 48 ksps rates, not variable rates.
tlv320aic27 stereo audio codec slas253 march 2000 34 post office box 655303 ? dallas, texas 75265 registers 36h and 38hesix-channel volume control these read/write registers control the output volume of the four optional pcm channels. note that since the tlv320aic27 only supports four internal dacs, depending upon which id has been selected via the cid pins 45 and 46, these registers may or may not have effect. the fields behave the same as the master volume control register, which offers attenuation but no gain. if gain is required, then the pcm dac mixer pgas corresponding to each dac should be used. if quad mode is selected and id = 10 or 11, then either 36h or 38h controls the level of the rear dac outputs onto the line level pins 39 and 41. surround data which is mapped from the surround data slots out onto the gpio pins as i 2 s data may not have its level adjusted. the mute bit will, however, mute the data to all 0s. modem registers (index 3ch and 56h) the contents of these registers control modem function. register 3ch extended modem id the extended modem id is a read/write register that primarily identifies the enhanced codecs modem afe capabilities. the default value depends on features and hardware configuration. writing any value to this register performs a warm modem afe reset (register range 3c56h), including gpio (register range 4c54h). the warm reset causes all affected registers to revert to their default values. note that for amc '97 parts, the audio and modem afe should be logically independent (writes to register 0h reset audio only). lin1 = 1 indicates that the first line is supported set when tlv320aic27 is in modem mode1 = 1 lin2 = 1 indicates that the second line is supported supported on tlv320aic27 when dlm is set hset = 1 indicates that the handset dac/adc is supported not supported on tlv320aic27 cid1 = 1 indicates that caller id decode for line1 is supported not supported on tlv320aic27 cid2 = 1 indicates that caller id decode for line2 is supported not supported on tlv320aic27 id1, id0 is a two-bit field which indicates the codec configuration: primary is 00; secondary is 01, 10, or 11 register 3eh extended-modem status control the extended-modem status and control register functions similarly to the original ac'97 power-down control/status register located at index 26h. the (a)mc '97 codec must restrict modem and handset power-down control/status to this register, since all of the functions are provided here. therefore, the (a)mc'97 codec (and ac'97 digital controller, of course) must ignore bits mdm and pr7 in register 26h and use what is included here. when the gpio section is powered down all outputs must be 3-state and input slot 12 should be marked invalid when the ac link is active. when slot 12 is invalid, register 54h (gpio pin status register) reports 0s. in addition, the codec should force sdata_in slot 12 to all 0s. bits 7 to 0 are read-only, and 1 indicates modem afe subsystem readiness gpio = 1 indicates gpio-ready mref = 1 indicates modem vrefs up to nominal level adc1 = 1 indicates modem line1 adc ready dac1 = 1 indicates modem line1 dac ready adc2 = 1 indicates modem line2 adc ready supported on tlv320aic27 when dlm is set dac2 = 1 indicates modem line2 dac ready supported on tlv320aic27 when dlm is set hadc = 1 indicates handset adc ready not supported on tlv320aic27 hdac = 1 indicates handset dac ready not supported on tlv320aic27
tlv320aic27 stereo audio codec slas253 march 2000 35 post office box 655303 ? dallas, texas 75265 register 3eh extended-modem status control (continued) bits 15 to 8 are read/write and control modem afe subsystem power down. the tlv320aic27 power-up/down functions are entirely controlled from register 26h. however, the following registers are aliased onto the appropriate control bits in registers 26h. pra = 1 indicates gpio power down prb = 1 indicates modem vref off no separate modem vref on tlv320aic27, aliases from pr3 prc = 1 indicates modem line1 adc off aliases from pr0 prd = 1 indicates modem line1 dac off aliases from pr1 pre = 1 indicates modem line2 adc off not supported on tlv320aic27 prf = 1 indicates modem line2 dac off not supported on tlv320aic27 prg = 1 indicates handset adc off not supported on tlv320aic27 prh = 1 indicates handset dac off not supported on tlv320aic27 bits 7 to 0 are read-only: a 1 indicates modem afe subsystem readiness. bits 15 to 8 are read/write and control modem afe subsystem power down. writing enables (0) to the above aliased pr bits is allowed, and will write enable to the appropriate prn bit. however, writing disables (1) is not allowed. register 40h line1 adc/dac sample rate the read/write register 40h controls the modem dac and adc sample rates. this register is only functional if modem mode1 = 1 is selected from pins 30 and 40. the adc only uses this sample rate if the input to the record mux is also selected, as the right adc in register 1ah is phone. note that only the recommended sample rates are supported. if alternative sample rates are selected, the rate defaults to the nearest sample rate supported, and that value is read back. register 46h to 48h line1 and line2 adc level these registers are not supported in tlv320aic27. register 04h is used to control tx modem level. register 56h miscellaneous modem afe status/control this read/write register defines the loop-back modes available for the modem line and handset adcs/dacs described in the intel specification. line1 adc loopback-mode 001 l1b0 is supported. gpio function note that only gpio pins 11 to 13 are supported. these pins are available to the user, unless used for i 2 s mode. the gpio mode overrides the i 2 s function. register 4ch gpio pin-configuration register the gpio pin configuration register is a read/write register that specifies whether a gpio pin is configured for input (1), or for output (0), and is accessed via the standard slots 1 and 2 command address/data protocols. if a gpio pin is implemented, the respective gcx bit should be readable/writeable and set to 1. if a gpio is not implemented, then the respective gcx bit is read-only and set to 0. this informs the software how many gpio pins have been implemented. it is up to the ac'97 digital controller to send the desired gpio pin value over output slot 12 in the outgoing stream of the ac link before configuring any of these bits for output. the default value of this register (3800h) after cold reset or register reset is all pins configured as inputs.
tlv320aic27 stereo audio codec slas253 march 2000 36 post office box 655303 ? dallas, texas 75265 register 4eh gpio pin polarity/type the gpio pin polarity/type is a read/write register that defines the gpio input polarity (0 = low, 1 = high active) when a gpio pin is configured as an input. it defines gpio output type (1 = cmos, 0 = open drain) when a gpio pin is configured as an output. the default value of this register (ffffh) after cold or register reset is all pins active high. nonimplemented gpio pins always return 1s. register 50h gpio pin sticky control the gpio pin sticky control is a read/write register that defines gpio input type (0 = nonsticky, 1 = sticky) when a gpio pin is configured as an input. gpio inputs configured as sticky are cleared by writing a 0 to the corresponding bit of the gpio pin status register 54h (see below), or by resetting it. the default value of this register (0000h) after a cold or register reset. unimplemented gpio pins always return 0s. sticky is defined as edge-sensitive, nonsticky is defined as level-sensitive. register 52h gpio pin wake-up control the gpio wake-up pin is a read/write register that provides a mask for determining if an input gpio change will generate a wake up or a gpio_int (0 = no, 1 = yes). when the ac link is powered down (register 26h pr4 = 1 for primary codecs), a wake-up event triggers the assertion of sdata_in. when the ac link is powered up, a wake-up event will appear as gpio_int = 1 on bit 0 of input slot 12. gpio_int is also flagged when the link is active. an ac-link wake-up interrupt is defined as a 0 to 1 transition of sdata_in when the ac link is powered down (register 26h pr4 = 1). the gpio bits that have been programmed as inputs (sticky and wake-up) will cause an ac-link wake-up event (transition of sdata_in from 0 to 1) upon either (high-to-low) or (low-to-high) transition (depending on pin polarity) only if the ac link was powered down. the default value of this register (0000h) after a cold or register reset is all 0s, specifying no wake-up event. nonimplemented gpio pins always return 0s. register 54h gpio pin status the gpio status is a read/write register that reflects the state of all gpio pins (inputs and outputs) on slot 12. the value of all gpio pin inputs and outputs comes in from the codec on slot 12 at every frame. this value is also available for reading as gpio pin status via the standard slots 1 and 2 command address/data protocols. gpio inputs configured as sticky are cleared by writing a 0 to the corresponding bit of register 54h. bits corresponding to unimplemented gpio pins should be forced to zero in this register and input slot 12. gpio bits that have been programmed as inputs and sticky, upon either (high-to-low) or (low-to-high) transition, depending on pin polarity, will cause the individual gpio bit to be asserted to 1 and remain asserted until a write of 0 to that bit. the normal way to set the desired value of a gpio output pin is to set the control bit in output slot 12. if configured as an input, the default value of this register after a cold or register reset is always the state of the gpio pin. register 56h miscellaneous modem afe status/control not supported in this mode. vendor reserved registers (index 5ah and 7ah) these registers are vendor-specific. do not write to these registers unless the vendor id register has been checked first to ensure that the driver knows the source of the ac`97 component. values stored in this register are used to provide vendor-specific modes for the manufacturer.
tlv320aic27 stereo audio codec slas253 march 2000 37 post office box 655303 ? dallas, texas 75265 vendor reserved registers (index 5ah and 7ah) (continued) table 19. vendor register 5ah bit allocation and default states bit name default action when set to 1 test-only bits not normal use aev adc evaluation 0 adc evaluation mode select bit do not use bb biasboost 0 increases analog bias currents by 50% trm tstrecmux 0 enables record mux test mode. recmux outputs summed into the front and rear dac output path. hic halficonv 0 halves bias current to the converters him malfimix 0 halves bias current to the mixer block dds dither disable 0 disables adc and dac digital dither do not use rts ram test mode 0 digital test mode do not use dft dac fit test 0 digital test mode do not use aft adc fir test 0 digital test mode do not use dts dac test 0 digital test mode do not use ats adc test 0 digital test mode do not use user bits and adc no dac 0 select stereo mix into adc as having no dac signal r2s rev 2.1 switch 0 closes rev 2.1 switch when set (see figure 15) i 2 s i 2 s enable 0 enables i 2 s data and clock onto gpio pins 43, 44, 48 dlm dual line modem 0 selects support for line2 dac and adc slots amd automute disable 0 disables automute function on the front and rear dacs vendor-specific gain control registers (index 70h to 74h) these three registers control the gain and mute functions applied to the front and rear mixer paths, and the rear channel dac gains. these pgas are not accommodated in the intel specification, but are required in order to build a flexible quad surround sound device. the function is as per the other mixer pgas. however, the default value of the register changes depending upon the mode of operation of the device is, as shown in table 20. table 20. vendor-specific pga default values, vendor id registers (index 7ch to 7eh) default value for register mode rear dac reg 70h front mixer reg 72h rear mixer reg 74h rev 2.1 switch rev 2.1 (00) 8808 0808 8808 closed rev 2.1 six-channel (01) 8808 0808 8808 closed quad (10) 8808 0808 0808 open modem (11) 0808 0808 0808 open this register is use for specific vendor identification, if so desired. the id method is microsoft's ? plug and play vendor id code. the first character of that id is f7 to f0, the second character is s7 to s0, and the third character is t7 to t0. these three characters are ascii encoded. the rev7 to rev0 field is for the vendor revision number. for the tlv320aic27, the vendor id is set to txn3 if mode1 = 0, and to txn4 if mode1 = 1. microsoft is a registered trademark of microsoft corporation
tlv320aic27 stereo audio codec slas253 march 2000 38 post office box 655303 ? dallas, texas 75265 operational mode description operational modes the tlv320aic27 has four modes of operation: two-channel, six-channel i 2 s, quad, and modem. the mode is determined by pins 30 and 40, as shown in table 21. table 21. modes of operation mode1 (mode40) mode0 (pin30) operational mode resulting device behavior 0 0 basic two-channel mode codec 0 1 six-channel i 2 s six-channel mode codec 1 0 quad quad dac mode (with i 2 s six-channel support) 1 1 modem modem dac mode basic mode in basic mode, the tlv320aic27 comprises a stereo 18-bit codec, (that is, two adcs and two dacs) plus a comprehensive analog mixer with four sets of stereo inputs, plus one phone input, two microphone inputs, and one pc-beep input. the tlv320aic27 supports 18-bit resolution within the dac and adc functions. however, the ac'97 serial interface specification allows any word length up to 20-bits to be written to, or read from the ac'97 codec. these words are msb-justified, and any unused lsbs simply defaults to 0. it is anticipated that 16-bit words will be used in most applications. therefore, for the dac, 16-bit words will be downloaded into the codec from the controller, along with padding of 0s to make the 16-bit word up to 20-bit in length. in this case, the tlv320aic27 processes the 16-bit word along with 0 padding bits in the two lsb locations (to make it 18-bit). at the adc output, the tlv320aic27 provides an 18-bit word, again with 0s in the two lsb locations (20-bit). the ac'97 controller then ignores the four lsbs of the 20-bit word. when the tlv320aic27 is interrogated, its response indicates it is an 18-bit device. an internally generated midrail reference is provided at pin cap2 which is used as the chip reference. this pin should be heavily decoupled. basic mode features vendor id reads back as txn3 two channels of adc and dac conversion provided, with all recommended audio and modem sample rates supported via the audio sample-rate registers 2ch and 32h master/slave id0/1 supported headphone/line level outputs (duplicating the main outputs) supported, with gain control from register 04h 3d stereo enhanced sound supported master volume control register maps to the location dependant on selected id: (id 00 or 01 uses master volume at register 02h, id 10 uses 38h (surround volume), and id 11 uses 36h (lfe, center volume) quad mode the tlv320aic27 codec comprises two channels of adc and four channels of dac. this enables a four-channel surround sound solution to be implemented (quad mode). a symmetric mixer is provided which allows analog signals such as cd inputs to be mixed into both front and rear channel paths simultaneously. alternatively, the device can be configured in six-channel i 2 s mode. in this mode the device uses three gpio pins to output rear channel and center and lfe data in i 2 s format to an external dac to build a full six-channel surround sound solution.
tlv320aic27 stereo audio codec slas253 march 2000 39 post office box 655303 ? dallas, texas 75265 quad mode (continued) the two additional dac channels are enabled in this mode, using the line level output pins 39 and 41 as outputs. an additional mixer block in this path allows the analog mix, excluding the front dac channels, to be summed into the rear channel mix. additional gain controls (pgas) are provided to allow adjustment of front and rear mix levels separately (registers 72h and 74h) prior to summing the analog mix to these channels. the rear channel dacs are also gain-adjustable using register 70h. this function duplicates the features provided for the front dac channel (gain range, step size, etc.). quad mode features vendor id reads back txn4 all six audio channels flagged as supported (if i 2 s enable bit is set) headphone channel flagged as not supported (bit id4 in register 00h) four channels of dac and two channels of adc conversion available, with all recommended audio and modem sample rates supported via the audio sample-rate registers 2ch (front channels, slots 3 and 4), 2eh (rear channels; slots 7 and 8), and 32h (adcs). note that if id is selected as 11, register 30h is used for sample rate of lfe channel, slot 9. gpio capability supporting bits 11 to 13 flagged as supported master/slave id0/1 supported, with automatic remapping of the rear or lfe/center dac slot data onto the rear dacs when id 10 or 11 are selected (normally surround slots are mapped onto the rear dacs). lfe and center channel data, plus a duplicate of the rear channel data, is sent from the gpio pins in i 2 s format, at 48 ksps rate (no variable rates supported by the i 2 s outputs). headphone/line level outputs used to output the rear dac and mixer channel, with volume controlled from register 38h. 3d stereo enhancement supported master volume control register maps to the location dependant on selected id: id 00 or 01 uses master volume at register 02h, id 10 uses 38h (surround volume), and id 11 uses 36h (lfe, center volume). in id11 bits 7 and 15 act as left and right mute. dac mute (reg18h) automatically demuted when id is 1x, that is, used as surround dac or lfe/center when surround or lfe/center master volume is demuted. in order to achieve the above functionality, the following changes to the revision 2.1 compliant defaults are required: ? revision 2.1 legacy compliance switch is opened (can be closed using rev2sw bit in register 5ah) ? rear channel mixer pga default is now not muted, 0-db gain (same as front channel mixer) ? lnlvl pin volume control is now controlled from 02h, unless id = io when volume control is from 38h ? rear dac level set by register 70h, default is 0-db not-muted ? front mixer and rear mixer gains set in registers 72h and 74h
tlv320aic27 stereo audio codec slas253 march 2000 40 post office box 655303 ? dallas, texas 75265 six-channel i 2 s mode in this mode, the device now has six-channel support and gpio capability. rear and lfe center dac data is mapped onto the gpio output pins as i 2 s data when these data slots are tagged as valid. the i 2 s enable bit is set in register 5ah. enabling of i 2 s overrides the gpio function. six-channel i 2 s mode features vendor id reads back as txn3 adc and dac conversion channels provided rear and lfe/center dac slots flagged as supported in extended audio capability register 28h gpio capability supporting bits 1113 flagged as supported master/slave id0/1 supported surround audio data not sent to the dacs is sent from the gpio pins in i 2 s format, at 48 ksps rate (no variable rates supported by the i 2 s outputs). headphone/line level outputs duplicating the main outputs supported, with gain control from register 04h. 3d stereo enhanced sound supported master volume control register maps to the location dependant on selected id: id 00 or 01 uses master volume at register 02h, id 10 uses 38h (surround volume), and id 11 uses 36h (lfe, center volume). in this case, bits 7 and 15 act as left and right mute. gpio pins and i 2 s the ac'97 revision 2.1 specification has provisions for up to 16 programmable io pins. within the 48-pin tqfp package used, provision has been made for three pins to be used as gpio pins. these pins (numbers 43, 44, 48) are also used as i 2 s output pins to support multichannel operation. when pins 43, 44, and 48 are used as gpio pins, they are mapped onto bits 11, 12, and 13, respectively, in the ac-link slot 12. these optional locations may be configured in any wayeas inputs or outputs, as supporting interrupt operation, etc., offering maximum flexibility to the user. the appropriate gpio control registers are supported to control these pins. when pins 43, 44, and 48 are used as i 2 s pins, pin 48 becomes the shared lrclk with frequency fixed at 48 khz, and pins 43 and 44 become the output data clocked out at the bitclk rate. thus, to connect an external dac, configure it in i 2 s mode as follows: ? connect bitclk signal from the tlv320aic27 to sclk on the dac. ? connect bitclk signal from the tlv320aic27 to sclk on the dac. ? connect bitclk from the ac'97 to bclk on the dac. ? connect pin 48 from the tlv320aic27 to lrclk on the dac. ? connect one of the two data pins, 43 or 44, on tlv320aic27 to the sdata pin on the dac. note that the dac must support serial interface data rates of up to 12.5 mhz. this is supported by texas instruments dac product line. i 2 s is enabled when gpio is not enabled (gpio bit 0 is enabled in register 3eh) and vendor-specific i 2 s (bit 7) in register 5ah is set. table 22 shows the connections to a typical i 2 s compatible stereo dac.
tlv320aic27 stereo audio codec slas253 march 2000 41 post office box 655303 ? dallas, texas 75265 gpio pins and i 2 s (continued) table 22. connection to external i 2 s dacs tlv320aic27 connection i 2 s dac connection bitclk sclk bitclk blck pin 48 gpio3 lrclk pin 43 gpio1 (lfe/center data in id00) sdata on external dac pin 44 gpio2 (surround data in id00) sdata on other external dac format pin connect for i 2 s mode deemph (if provided) disable configuration of these pins as gpio is explained in the control interface description. modem mode in modem mode, the modem tx data is mapped onto the rear dacs. rear dac sample rates are set by the modem's tx sample rate register 40h. extended modem capability register 3ch indicates that line1 is supported. modem mode features vendor id reads back txn4 headphone channel flagged as not supported (bit id4 in register 00h) four channels of dac and two of adc conversion available, with all recommended audio and modem sample rates supported via the audio sample rate registers 2ch (front dacs), 40h (rear dacs), and 32h (adcs in audio mode). adc samples are outputted onto both audio slots 3 and 4 and also onto line2/1 slots 10 and 5, respectively. line1 tx modem data is mapped onto the rear dacs as data and as inverted data, so that the pair of rear dacs produce a differential tx modem data output. right audio adc changes to use line1 sample rate 40h when input mix selects phone as its ip. the additional vendor-specific mode dlm is available via bit dlm in register 5ah. setting this bit provides support for line2 as well as line1 slots. rear dacs are mapped onto line1 and line2 tx modem data slots, and adc left and right outputs are mapped both onto normal audio slots 3 and 4 and also onto the line1 and line2 rx modem data slots. modem rate register 40h is used for both dacs, and the adc's use their normal sample rate registers (that is, audio registers), unless right channel is selected as phone, in which case they too use register 40h. if dlm bit is set in register 5ah, then line1 tx data is mapped onto the rear left dac, and line2 tx data is mapped onto the rear right dac. both rear dacs use the same sample rate from register 40h (if 42h is written to, 40h will be updated instead). the left adc always uses the normal adc audio rate register, except when rphone is selected in dlm mode, in which case it uses 40h. gpio capability supporting gpio (11 to 13) flagged as supported master/slave id0/1 supported, with automatic remapping of the rear or lfe/center dac slot data onto the front dacs when id 10 or 11 is selected. headphone/line level output pins 39 and 41 used to output the rear dac signals, with volume controlled from register 04h. rear mixer pga is fixed in mute condition. 3d-stereo enhancement supported
tlv320aic27 stereo audio codec slas253 march 2000 42 post office box 655303 ? dallas, texas 75265 modem mode features (continued) master volume control register maps to a location dependant on selected id: id 00 or 01 uses master volume at register 02h, id 10 uses 38h (surround volume), and id 11 uses 36h (lfe, center volume). in id11, bits 7 and 15 act as left and right mute. front dac mute (reg18h) automatically demuted when id is 1x. that is, it is used as surround dac or lfe/center when surround or lfe/center master volume is demuted. rear dac mute (reg70h) automatically demuted when 04h volume is demuted adcs always use record level from register 1ch in order to achieve the above functionality, the following changes to rev 2.1 compliant, or quad mode, defaults are made: ? rev 2.1 legacy compliance switch is opened (can be closed using rev2sw bit in register 5ah) ? rear channel mixer pga default is now permanently muted (it is unlikely that user will want to send the analog mix output onto the tx modem line output) ? tx modem level at the lnlvl pins still controlled from 04h rather than 46h or 48h (which would normally be the modem adc and dac level-control registers) ? rx adc input levels are still controlled from the normal adc record level register 1ch (rather than from 46h or 48h, due to the difficulty in reallocating left and right channel gain controls into two different registers). the ac'97 rev 2.1 specification allows for provision of up to 16 programmable io pins. within the 48-pin tqfp package used, provision has been made for three pins to be used as gpio pins. these pins (numbers 43, 44, and 48) are also used as i 2 s output pins to support multichannel operation. when used as gpio pins, pins 43, 44, and 48 are mapped onto bits 11, 12, and 13 in the ac-link slot 12. these optional locations may be configured in any way: as inputs or outputs, as supporting interrupt operation, etc., offering maximum flexibility to the user. the appropriate gpio control registers are supported to control these pins. configuration of these pins as gpio is explained in the control interface description. modem registers (index 3ch and 56h) the contents of these registers control modem function register 3ch extended modem id the extended modem id is a read/write register that primarily identifies the enhanced codecs modem afe capabilities. the default value will depend on features and hardware configuration. writing any value to this register performs a warm modem afe reset (register range 3c56h), including gpio (register range 4c54h). the warm reset causes all affected registers to revert to their default values. note: for amc '97 parts the audio and modem afe should be logically independent (writes to register 0h resets audio only). lin1 = 1 indicates first line is supported set when tlv320aic27 is in modem mode1 = 1 lin2 = 1 indicates second line is supported supported on tlv320aic27 when dlm is set hset = 1 indicates handset dac/adc is supported not supported on tlv320aic27 cid1 = 1 indicates that caller id decode for line1 is supported not supported on tlv320aic27 cid2 = 1 indicates that caller id decode for line2 is supported not supported on tlv320aic27 id1, id0 is a two-bit field which indicates the codec configuration: primary is 00; secondary is 01, 10, or 11
tlv320aic27 stereo audio codec slas253 march 2000 43 post office box 655303 ? dallas, texas 75265 register 3eh extended modem status control the extended modem status and control register functions similarly to the original ac'97 power-down control/status register, located at index 26h. the (a)mc '97 codec must restrict modem and handset power-down control/status to this register since all of the functions are provided here. therefore, the (a)mc'97 codec (and ac'97 digital controller, of course) must ignore bits mdm and pr7 in register 26h and use what is included here. when the gpio section is powered down, all outputs must be 3-state and input slot 12 should be marked invalid when the ac link is active. when slot 12 is invalid, register 54h (gpio pin status register) will report 0s. in addition the codec should force sdata_in slot 12 to all 0s. bits 7 to 0 are read only, 1 indicates modem afe subsystem readiness gpio = 1 indicates gpio ready mref = 1 indicates modem vrefs up to nominal level adc1 = 1 indicates modem line1 adc ready dac1 = 1 indicates modem line1 dac ready adc2 = 1 indicates modem line2 adc ready supported on tlv320aic27 when in dlm is set dac2 = 1 indicates modem line2 dac ready supported on tlv320aic27 when dlm is set hadc = 1 indicates handset adc ready not supported on tlv320aic27 hdac = 1 indicates handset dac ready not supported on tlv320aic27 bits 15 to 8 are read/write and control modem afe subsystem power down. tlv320aic27 power-up/down functions are entirely controlled from register 26h. however, the following registers are aliased onto the appropriate control bits in registers 26h. pra = 1 indicates gpio power-down prb = 1 indicates modem vref off no separate modem vref on tlv320aic27, aliases from pr3 prc = 1 indicates modem line1 adc off aliases from pr0 prd = 1 indicates modem line1 dac off aliases from pr1 pre = 1 indicates modem line2 adc off not supported on tlv320aic27 prf = 1 indicates modem line2 dac off not supported on tlv320aic27 prg = 1 indicates handset adc off not supported on tlv320aic27 prh = 1 indicates handset dac off not supported on tlv320aic27 bits 7 to 0 are read only, 1 indicates modem afe subsystem readiness. bits 15 to 8 are read/write and control modem afe subsystem power down. writing enables (0) to the above aliased pr bits is allowed and will write enable to appropriate prn bit. however, writing disables (1) is not allowed. register 40h line1 adc dac sample rate this read/write register 40h controls the modem dac and adc sample rate. this register is only functional if modem mode1 = 1 is selected from pins 30 and 40. the adc will only use this sample rate if in addition, the input to the record mux is selected, as right adc is phone in register 1ah. note only the recommended sample rates are supported. if alternative sample rates are selected the rate will default to the nearest sample rate supported, and that value will be read back register 46h to 48h line1 and line2 adc level these registers are not supported in tlv320aic27, register 04h being used to control tx modem level. register 56h miscellaneous modem afe status/control this read/write register defines the loop back modes available for the modem line and handset adcs/dacs described in the intel specification. line1 adc loopback mode 001 l1b0 is supported.
tlv320aic27 stereo audio codec slas253 march 2000 t emp l ate r e l ease d ate: 7 11 94 44 post office box 655303 dallas, texas 75265 ? table 23. serial interface register map description reg name d15 d14 d13 d12 d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 default 00h reset x se4 se3 se2 se1 se0 id9 id8 id7 id6 id5 id4 id3 id2 id1 id0 6150h 02h master volume mute x x ml4 ml3 ml2 ml1 ml0 x x x mr4 mr3 mr2 mr1 mr0 8000h 04h lnlvl volume mute x x ml4 ml3 ml2 ml1 ml0 x x x mr4 mr3 mr2 mr1 mr0 8000h 06h master volume mono mute x x x x x x x x x x mm4 mm3 mm2 mm1 mm0 8000h 0ah pcbeep volume mute x x x x x x x x x x pv3 pv2 pv2 pv0 x x000h 0ch phone volume mute x x x x x x x x x x gn4 gn3 gn2 gn1 gn0 8008h 0eh mic volume mute x x x x x x x x 20db x gn4 gn3 gn2 gn1 gn0 8008h 10h line in volume mute x x gl4 gl3 gl2 gl1 gl0 x x x gr4 gr3 gr2 gr1 gr0 8808h 12h cd volume mute x x gl4 gl3 gl2 gl1 gl0 x x x gr4 gr3 gr2 gr1 gr0 8808h 14h video volume mute x x gl4 gl3 gl2 gl1 gl0 x x x gr4 gr3 gr2 gr1 gr0 8808h 16h aux volume mute x x gl4 gl3 gl2 gl1 gl0 x x x gr4 gr3 gr2 gr1 gr0 8808h 18h pcm out volume mute x x gl4 gl3 gl2 gl1 gl0 x x x gr4 gr3 gr2 gr1 gr0 8808h 1ah record select x x x x x sl2 sl1 sl0 x x x x x sr2 sr1 sr0 0000h 1ch record gain mute x x x gl3 gl2 gl1 gl0 x x x x gr3 gr2 gr1 gr0 8000h 20h general-purpose pop st 3d ld x x mix ms lpbk x x x x x x x 8000h 22h 3d control x x x x x x x x x x x x dp3 dp2 dp1 dp0 0000h 24h reserved x x x x x x x x x x x x x x x x 0000h 26h power/down control status eapd pr6 pr5 pr4 pr3 pr2 pr1 pr0 x x x x ref anl dac adc 000fh 28h extended audio id id1 id0 x x x x amap ldac sdac cdac x x vrm x dra vra 0281h 2ah extended audio stat/ctrl x prl prk prj pri x madc ldac sdac cdac x x vrm x dra vra 0080h 2ch front dac rate sr15 sr14 sr13 sr12 sr11 sr10 sr9 sr8 sr7 sr6 sr5 sr4 sr3 sr2 sr1 sr0 bb80h 2eh rear dac rate sr15 sr14 sr13 sr12 sr11 sr10 sr9 sr8 sr7 sr6 sr5 sr4 sr3 sr2 sr1 sr0 bb80h 30h lfe dac rate sr15 sr14 sr13 sr12 sr11 sr10 sr9 sr8 sr7 sr6 sr5 sr4 sr3 sr2 sr1 sr0 bb80h 32h audio adc rate sr15 sr14 sr13 sr12 sr11 sr10 sr9 sr8 sr7 sr6 sr5 sr4 sr3 sr2 sr1 sr0 bb80h 36h 6ch vol c,lfe mute x x lfe4 lfe3 lfe2 lfe1 lfe0 mute x x cnt4 cnt3 cnt2 cnt1 cnt0 8080h 38h 6ch vol l,r surr mute x x lsr4 lsr3 lsr2 lsr1 lsr0 mute x x rsr4 rsr3 rsr2 rsr1 rsr0 8080h 3ch extended modem id id1 id0 x x x x x x x x x cid2 cid1 hset lin2 lin1 x00xh 3eh extended modem status prh prg prf pre pd prc prb pra hdac hadc dac2 adc2 dac1 adc1 mref gpio 0100h 40h line1 sample rate adc/dac sr15 sr14 sr13 sr12 sr11 sr10 sr9 sr8 sr7 sr6 sr5 sr4 sr3 sr2 sr1 sr0 bb80h 42h line2 sample rate adc/dac sample rates written to 42h will alias onto 40h na 46h line1 dac/adc level not supported set tx modem levels by writing to rear dac pga 04h na
tlv320aic27 stereo audio codec slas253 march 2000 post office box 655303 dallas, texas 75265 ? 45 table 23. serial interface register map description (continued) reg name d15 d14 d13 d12 d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 default 48h line2 dac/adc level not supported set tx modem levels by writing to rear dac pga 04h na 4ch gpio pin config not supported na 4eh ggpio pin type na 50h ggpio pin sticky na 52h ggpio wake-up na 54h ggpio pin status na 56h misc modem stat/ctrl cid2 cid1 cidr mlnk x hsb2 hsb1 hsb0 x l2b2 l2b1 l2b0 x l1b2 l1b1 l1b0 0000h 5ah vendor reserved x x x x x x x x x x x x x x x x x 70h rear pcm out volume not supported na 72h front mixer volume mute x x gl4 gl3 gl2 gl1 gl0 x x x gr4 gr3 gr2 gr1 gr0 8808h 74h rear mixer volume not supported na 7ah vendor reserved x x x x x x x x x x x x x x x x x 7ch vendor id1 f7 f6 f5 f4 f3 f2 f1 f0 s7 s6 s5 s4 s3 s2 s1 s0 574dh 7eh vendor id2 t7 t6 t5 t4 t3 t2 t1 t0 rev7 rev6 rev5 rev4 rev3 rev2 rev1 rev0 4c03h
tlv320aic27 stereo audio codec slas253 march 2000 46 post office box 655303 ? dallas, texas 75265 detailed timing diagrams, av dd = 5 v, dv dd = 3.3 v, gnd = 0 v, t a = 0 c to 70 c (unless otherwise stated) all measurements are taken at 10% to 90% v dd , unless otherwise stated. all the following timing information is assured, not tested. sync bit_clk sdata_out write to 0x20 data pr4 don't care sdata_in slot 1 slot 2 t (s2_pdown) parameter min typ max unit t (s2_pdown) end of slot 2 to bitclk sdatin low 1 m s figure 15. ac-link power-down timing resetb bit_clk t (rst_low) t (rst2clk) parameter min typ max unit t (rst_low) resetb active-low pulse width 1 m s t (rst2_clk) resetb inactive to bit_clk startup delay 162.8 ns figure 16. cold reset timing
tlv320aic27 stereo audio codec slas253 march 2000 47 post office box 655303 ? dallas, texas 75265 detailed timing diagrams, av dd = 5 v, dv dd = 3.3 v, gnd = 0 v, t a = 0 c to 70 c (unless otherwise stated) (continued) sync bit_clk t (sync_high) t (sync2clk) parameter min typ max unit t (sync_high) sync active high pulsewidth 1.3 m s t (sync2_clk) sync inactive to bit_clk startup delay 162.4 ns figure 17. warm reset timing bit_clk t (clk_period) t clk_high t clk_high sync t sync_period t (sync_low) t (sync_high) t (clk_high) t (clk_low) parameter min typ max unit bit_clk frequency 12.288 mhz t (clk_period) bit_clk period 81.4 ns bit_clk output jitter 750 ps t (clk_high) bit_clk high pulse width (see note 2) 32.56 40.7 48.84 ms t (clk_low) bit_clk low pulse width (see note 2) 32.56 40.7 48.84 ns sync frequency 48 khz t (sync_period) sync period 20.8 m s t (sync_high) sync high pulse width 1.3 m s t (sync_low) sync low pulse width 19.5 m s note 2: worst-case duty cycle restricted to 40/60. figure 18. clock specifications (50-pf external load)
tlv320aic27 stereo audio codec slas253 march 2000 48 post office box 655303 ? dallas, texas 75265 detailed timing diagrams, av dd = 5 v, dv dd = 3.3 v, gnd = 0 v, t a = 0 c to 70 c (unless otherwise stated) (continued) bit_clk t su sync sdata_out t h parameter min typ max unit t su setup to falling edge of bit_clk 15 ns t h hold from falling edge of bit_clk 5 ns note: setup and hold time parameters for sdata_in are with respect to ac'97 controller. figure 19. data setup and hold (50 pf external load) t r(clk) t f(clk) bit_clk t r(sync) t f(sync) sync t f(din) sdata_in t f(dout) sdata_out t r(din) t r(dout) parameter min typ max unit t r(clk) bit_clk rise time 2 6 ns t f(clk) bit_clk fall time 2 6 ns t r(sync) sync rise time 2 6 ns t f(sync) sync fall time 2 6 ns t r(din) sdata_in rise time 2 6 ns t f(din) sdata_in fall time 2 6 ns t r(dout) sdata_out rise time 2 6 ns t f(dout) sdata_out fall time 2 6 ns figure 20. signal rise and fall times (50-pf external load)
tlv320aic27 stereo audio codec slas253 march 2000 49 post office box 655303 ? dallas, texas 75265 recommended external components 1 9 4 7 dvdd1 dvdd2 dvss1 dvss2 25 38 26 42 27 28 29 31 33 34 vref vrefout afilt1 cap1 cx3d1 cx3d2 avss2 avss1 avdd2 avdd1 dvdd avdd stereo output dgnd agnd 32 cap2 agnd agnd agnd 35 lineoutl 36 lineoutr 37 monoout 39 lnlvloutl 41 lnlvloutr line level stereo 43 gpio1 44 gpio2 48 gpio3 47 eapd4 xtlout 3 xtlin 2 pcbeep 12 phone 13 auxl 14 auxr 15 videol 16 videor 17 cdl 18 cdgnd 19 cdr 20 mic1 21 mic2 22 lineinl 23 lineinr 24 m0 30 m1 40 cid1 46 cid2 45 avss oerational mode control mixer inputs sdataout 5 bitclk 6 sdatain 8 sync 10 resetb 11 aclink mono output dgnd c3 c4 c18 c19 c20 c21 c22 c23 c25 c24 c26 c27 c28 c29 c30 c31 c32 c33 c35 xt c34 c17 c16 c15 c14 c13 c12 c11 c10 c9 c8 c7 c6 c5 c2 c1 + + ++ + tlv320aic27 + + + + to i2s dacs/daa control avdd (modem out) notes: a. pins 27, 29 and 31 are internally connected. it is recommended that capacitors only be connected to one of these pins. b. c1 to c28 should be as close to aic27 as possible. c. agnd and dgnd should be connected as close to aic27 as possible. figure 21. external components diagram
tlv320aic27 stereo audio codec slas253 march 2000 50 post office box 655303 ? dallas, texas 75265 recommended external components values table 24. external component values component reference suggested value description c1 to c4 10 nf decoupling for dvdd and avdd c5 to c17 470 nf ac coupling capacitors for setting dc level of analog inputs to vcap1. value chosen to give corner frequency below 20 hz for a minimum of 10-k w input impedance. c18 1 m f c19 0.1 m f c20 10 m f c21 0.1 m f c22 10 m f reference decoupling capacitors for adc, dac, mixer, and cap2 references. ceramic type or similar. c23 0.1 m f c24 10 m f c25 0.1 m f c26 10 m f c27 100 nf 3d low-pass filter. this value sets nominal 100 hz. c28 47 nf 3d high-pass filter. this value sets nominal 1 khz. c29 to c33 10 m f output ac-coupling caps to remove vref dc level from outputs c34 and c35 22 pf optional capacitors for better crystal frequency stability xt 24.576 mhz ac'97 master clock frequency. a bias resistor is not required, but if connected will not affect operation if value is large (above 1 m w ). recommendations for 3.3-v operation the device performance with av dd = 3.3 v is shown in the electrical characteristics section. in 3.3-v analog operation, midrail reference scales to 1.5 v. all adc and dac references are 3/5 of their nominal 5-v value. input and output signals that are 1 vrms in 5-v applications scale to 660 mvrms in 3.3-v applications. if 1-vrms output is required, the mixer gain-adjust pgas need to be increased by a factor of 3 in 1.5-db steps.
tlv320aic27 stereo audio codec slas253 march 2000 51 post office box 655303 ? dallas, texas 75265 mechanical data pfb (s-pqfp-g48) plastic quad flatpack 4073176 / b 10/96 gage plane 0,13 nom 0,25 0,45 0,75 seating plane 0,05 min 0,17 0,27 24 25 13 12 sq 36 37 7,20 6,80 48 1 5,50 typ sq 8,80 9,20 1,05 0,95 1,20 max 0,08 0,50 m 0,08 0 7 notes: a. all linear dimensions are in millimeters. b. this drawing is subject to change without notice. c. falls within jedec ms-026
important notice texas instruments and its subsidiaries (ti) reserve the right to make changes to their products or to discontinue any product or service without notice, and advise customers to obtain the latest version of relevant information to verify, before placing orders, that information being relied on is current and complete. all products are sold subject to the terms and conditions of sale supplied at the time of order acknowledgment, including those pertaining to warranty, patent infringement, and limitation of liability. ti warrants performance of its semiconductor products to the specifications applicable at the time of sale in accordance with ti's standard warranty. testing and other quality control techniques are utilized to the extent ti deems necessary to support this warranty. specific testing of all parameters of each device is not necessarily performed, except those mandated by government requirements. of course, customers are responsible for their applications using ti components. in order to minimize risks associated with the customer's applications, adequate design and operating safeguards must be provided by the customer to minimize inherent or procedural hazards. ti assumes no liability for applications assistance or customer product design. ti does not warrant or represent that any license, either express or implied, is granted under any patent right, copyright, mask work right, or other intellectual property right of ti covering or relating to any combination, machine, or process in which such semiconductor products or services might be or are used. ti's publication of information regarding any third party's products or services does not constitute ti's approval, warranty or endorsement thereof. copyright ? 2000, texas instruments incorporated

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