View AN4170_8246345.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

november 2012 doc id 023709 rev 1 1/15 AN4170 application note 20 w + 20 w dual btl class-d au dio amplifier demonstration board based on the tda7491hv introduction the steval-cca042v1 is a demonstration board designed for the evaluation of the tda7491hv dual btl class-d audio amplifier. this application note provides the board specifications and a quick-start list for standalone operation. also included are the schematic, printed circuit board layout and bill of material. due to its high efficiency, the device, assemb led in the psso36 (slug-down) package, is capable of dissipating heat without a heatsink. jumpers on the board allow the configuration of the amplifier in order to verify the input signal as single-ended or differential and choose the fixed gain settings. microswitches are also provided to enable the standby and mute functions. the main features of the tda7491hv include: 20 w + 20 w continuous output power at thd =10%, r l = 8 , v cc = 18 v 9.5 w + 9.5 w continuous output power at thd = 10%, r l = 8 , v cc =12 v wide-range, single-supply operation (5 v - 18 v) high efficiency ( = 90%) four selectable, fixed gain settings (20 db, 26 db, 30 db and 32 db) differential inputs to minimize common-mode noise filterless operation standby and mute features short-circuit and thermal overload protections externally synchronizable figure 1. steval-cca042v1 www.st.com
contents AN4170 2/15 doc id 023709 rev 1 contents 1 operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.1 power supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.2 demonstration board preparation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.3 inputs and outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.4 powering up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1.5 gain settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1.6 single-ended or differential input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1.7 board schematic and bill of material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2 pcb layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 2.1 layout views . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 2.2 design guidelines for pcb schematic and lay out . . . . . . . . . . . . . . . . . . . . 9 2.2.1 dumping network . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2.2.2 main filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 2.2.3 layout recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 3 revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
AN4170 operation doc id 023709 rev 1 3/15 1 operation the tda7491hv demonstration board specifications are as follows: power supply voltage range: 5 v to 18 v number of channels: 2 btl (bridge-tied load) stereo load impedance: 4 to 8 gain settings: 20 db, 26 db, 30 db, 32 db undervoltage protection (uvp): 4.5 v 1.1 power supply a single power supply is required to feed the tda7491hv demonstration board via the connector j2 (see figure 2 ). connect the positive voltage of the 25 v/ 5 a dc power supply to the +vcc pin and the negative to gnd. note: voltage range 5 v to 18 v = 5 a current capability 1.2 demonstration board preparation 1. ensure that the power supply is switched off. 2. connect the regulated power supply, adjusted in the device operating range, to the connector j2 (observe the polarity). 1.3 inputs and outputs 1. connect the loads across the connectors j3 (lef t) and j4 (right), the specified impedance ranges from 6 to 8 . 2. connect the analog audio inputs, either differential or single-ended, to the l-input and r-input rca plugs (j1). refer to figure 2: demonstration board connections on page 4 . table 1. input configuration input configuration jumper j8 (right) jumper j9 (left) differential open open single-ended closed closed
operation AN4170 4/15 doc id 023709 rev 1 figure 2. demonstration board connections 1.4 powering up before powering up the demonstration board, ensure that the tda7491hv is in standby and mute conditions and the gain is set to the desired value (default 20 db). verify also the dedicated switches and jumpers. figure 3. standby and mute switches analog inputs gnd +vcc dummy load dummy load stby mute table 2. standby and mute settings stby (s1) mute (s2) status l l stby l h stby hlmute hhplay l l h h s1= stby s2= mute
AN4170 operation doc id 023709 rev 1 5/15 1.5 gain settings figure 4. jumpers j5 and j6 1.6 single-ended or differential input jumpers j8 and j9 are used to modify the input signal configuration. figure 5. jumpers j8 and j9 table 3. configuration of jumpers j5 and j6 gain 0 (j5) gain 1 (j6) gain (db) open (l) open (l) 20 open (l) closed (h) 26 closed (h) open (l) 30 closed (h) closed (h) 32 table 4. configuration of jumpers j8 and j9 input configuration l eft (j9) right (j8) differential open open single-ended closed closed
operation AN4170 6/15 doc id 023709 rev 1 1.7 board schematic and bill of material figure 6. steval-cca042v1 schematic ,1/ ,1/ ,15 ,15 9&& *1' 287/ 287/ 2875 2875 7'$3 lc filter component load l1,l2,l3,l4 c20,c26 4 ohm 6 ohm 8 ohm 15 uh 22 uh 33 uh 220 nf 220 nf 470 nf 087( 67%< 932:(56833/< )ru6lqjoh(qghg )ru6lqjoh(qghg,qsxw input synclk vdds vcc 3v3 16 ohm 68 uh 220 nf &/$66'$03/,),(5 (tda7491p/lp/hv) option + c23 470uf 25v c5 100nf r3 39k l4 c1 470nf c2 470nf c11 470nf c12 470nf c8 100nf c25 100nf c19 100nf c27 330pf r6 22r l3 c28 100nf c24 100nf l1 c21 330pf r5 22r l2 c18 100nf c22 100nf c3 1nf c4 1nf c13 1nf c14 1nf 32 inpb 36 vss 9 outnb 5 pgndb 7 pvccb 3 outpb 10 outna 12 pvcca 14 pgnda 16 outpa 33 innb 8 outnb 4 pgndb 21 mute 6 pvccb 2 outpb 29 svr 11 outna 1 sub_gnd 22 inpa 23 inna 27 sgnd 26 vdds 28 diag 19 vddpw 18 pgnd 20 stby 24 rosc 31 gain1 35 svcc 30 gain0 25 synclk 17 outpa 15 pgnda 34 vref 13 pvcca ic1 tda7492p r1 100k r7 22r c6 100nf r4 33k r2 n 5 n & q) c10 100nf & q) - - 2 1 3 6 2 1 3 6 & q) & x) 2 gnd 1 out 3 in ,& l4931cz33 + c15 2.2uf 16v 1 2 j4 1 2 j3 1 2 j2 - - 1 3 2 4 j1 + c7 2.2uf 16v + c16 1uf 16v + c17 1uf 16v r13 9.1k + c30 10uf 16v + c31 + c32 + c33
AN4170 operation doc id 023709 rev 1 7/15 table 5. bill of material package description qty reference manufacturer c0603 330 pf 50 v npo 5% 2 c21, c27 murata c0603 1 nf 50 v 10% 4 c3, c4, c13, c14 murata c0603 100 nf 50 v 10% 11 c5, c6, c8, c9, c10, c18, c19, c22, c24, c25, c28 murata c0603 470 nf 50 v 10% 4 c1, c2, c11, c12 murata c0603 2.2 f, 16 v 10% 3 c7, c15, c29 murata c0603 1 f, 16 v, 10% 2 c16, c17 murata e-cap 8x20 470 f, 25 v, 10%, pitch = 5.0 mm 1 c23 panasonic c1206 10 f, 25 v, 20%, y5v 4 c30, c31, c32, c33 murata mcap 7x5 220 nf, 50 v, 10% 2 c20, c26 murata r0603 22 ohm, 10%, 1/16 w 3 r5, r6, r7 murata r0603 2.2k ohm, 10%, 1/16 w 1 r8 murata r0603 9.1k ohm, 10%, 1/16 w 1 r13 murata r0603 33k ohm, 10%, 1/16 w 2 r2, r4 murata r0603 39k ohm, 10%, 1/16 w 1 r3 murata r0603 100k ohm, 10%, 1/16 w 1 r1 murata psso36 slug-down tda7491hv (sso36) slug-down 1 ic1 stmicroelectronics coil 10x10 33 h 2 a coil mss1046-333ml (1) 4 l1, l2, l3, l4 coilcraft rca-2p rca socket 2px2, type av2-8.4-12 1 j1 songcheng to92 l4931cz33, 3v3 regulator 1 ic2 stmicroelectronics cnn-terminal 2p, pitch = 5 mm connector terminal 3 j2, j3, j4 any source 2-way jumper 2p, pitch = 2.5 mm jumper 4 j5, j6, j8, j9 any source slide switch 3p, pitch = 2.5 mm 2 s1, s2 any source 1. alternate part mss1246/mss1260
pcb layout AN4170 8/15 doc id 023709 rev 1 2 pcb layout 2.1 layout views figure 7. top view of pcb layout figure 8. bottom view of pcb layout
AN4170 pcb layout doc id 023709 rev 1 9/15 figure 9. top view of pcb layout - with dimensions 2.2 design guidelines for pcb schematic and layout 2.2.1 dumping network the capacitor is mainly intended for high inductive loads and for common-mode noise attenuation. figure 10. dumping network c28 100nf c24 100nf
pcb layout AN4170 10/15 doc id 023709 rev 1 2.2.2 main filter the main filter is an lc butterworth based filter. the cutoff frequency must be chosen between the upper limit of the audio band (~20 khz) and the carrier frequency (310 khz). figure 11. main filter table 6. recommended values r load 8 6 l load 33 h 22 h c load 220 nf 220 nf
AN4170 pcb layout doc id 023709 rev 1 11/15 2.2.3 layout recommendations the following figures illustrate layout recommendations. solder the 100 nf bypass capacitors (x 7r) as close as possible to the ic v cc pins (recommended distance to be within 3 mm) in order to avoid spikes generated by the stray inductance caused by the copper supply lines. figure 12. capacitors soldered as close as possible to v cc pins solder the snubber networks as close as possible to the ic related pin. a voltage spike dangerous for device operation could occur if the snubber network is far from the output pins. it is recommended that the distance between the snubber network and the output pins be within 5 mm. figure 13. snubber networks soldered as close as possible to relevant ic pin ground pin and vcc pin of 100nf capacitor should be directly connected to the related ic p in
pcb layout AN4170 12/15 doc id 023709 rev 1 place the rc filter for the rosc pin close to the ic. figure 14. rc filter place the filter capacitor for svr, vr ef, svcc, vss and vddpw close to the ic. figure 15. filter capacitor
AN4170 pcb layout doc id 023709 rev 1 13/15 signal ground should be directly connected to the negative terminal of the bulk capacitor. figure 16. signal ground routing
revision history AN4170 14/15 doc id 023709 rev 1 3 revision history table 7. document revision history date revision changes 13-nov-2012 1 initial release.
AN4170 doc id 023709 rev 1 15/15 please read carefully: information in this document is provided solely in connection with st products. stmicroelectronics nv and its subsidiaries (?st ?) reserve the right to make changes, corrections, modifications or improvements, to this document, and the products and services described he rein at any time, without notice. all st products are sold pursuant to st?s terms and conditions of sale. purchasers are solely responsible for the choice, selection and use of the st products and services described herein, and st as sumes no liability whatsoever relating to the choice, selection or use of the st products and services described herein. no license, express or implied, by estoppel or otherwise, to any intellectual property rights is granted under this document. i f any part of this document refers to any third party products or services it shall not be deemed a license grant by st for the use of such third party products or services, or any intellectual property contained therein or considered as a warranty covering the use in any manner whatsoev er of such third party products or services or any intellectual property contained therein. unless otherwise set forth in st?s terms and conditions of sale st disclaims any express or implied warranty with respect to the use and/or sale of st products including without limitation implied warranties of merchantability, fitness for a parti cular purpose (and their equivalents under the laws of any jurisdiction), or infringement of any patent, copyright or other intellectual property right. unless expressly approved in writing by two authorized st representatives, st products are not recommended, authorized or warranted for use in milita ry, air craft, space, life saving, or life sustaining applications, nor in products or systems where failure or malfunction may result in personal injury, death, or severe property or environmental damage. st products which are not specified as "automotive grade" may only be used in automotive applications at user?s own risk. resale of st products with provisions different from the statements and/or technical features set forth in this document shall immediately void any warranty granted by st for the st product or service described herein and shall not create or extend in any manner whatsoev er, any liability of st. st and the st logo are trademarks or registered trademarks of st in various countries. information in this document supersedes and replaces all information previously supplied. the st logo is a registered trademark of stmicroelectronics. all other names are the property of their respective owners. ? 2012 stmicroelectronics - all rights reserved stmicroelectronics group of companies australia - belgium - brazil - canada - china - czech republic - finland - france - germany - hong kong - india - israel - ital y - japan - malaysia - malta - morocco - philippines - singapore - spain - sweden - switzerland - united kingdom - united states of america www.st.com

▲Up To Search▲

Price & Availability of AN4170

	To Download AN4170 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .