january 2006 p2041a rev 0.1 alliance semiconductor 2575 augustine drive ? santa clara, ca ? tel: 408.855.4900 ? fax: 408.855.4999 ? www.alsc.com notice: the information in this document is subject to change without notice. versatile emi reduction ic features ? fcc approved method of emi attenuation ? provides up to 20db of emi suppression ? generates a low emi spre ad spectrum clock of the input frequency ? optimized for 25mhz to 60mhz input frequency range ? internal loop filter minimizes external components and board space ? 4 selectable spread ranges ? sson control pin for spread spectrum enable and disable options ? low cycle-to-cycle jitter ? 3.3v or 5.0v operating voltage ? low power cmos design ? available in 8 pin soic and tssop packages product description the p2041a is a selectable spread spectrum frequency modulator designed specifically for pc peripheral and embedded controller markets. the p2041a reduces electromagnetic interference (emi) at the clock source which provides system wide reduction of emi of all clock dependent signals. the p2041a allows significant system cost savings by reducing the number of circuit board layers and shielding that are traditionally required to pass emi regulations. the p2041a uses the most efficient and optimized modulation profile approved by the fcc and is implemented in a proprietary all-digital method. the p2041a modulates the output of a single pll in order to ?spread? the bandwidth of a synthesized clock and, more importantly, decreases the peak amplitudes of its harmonics. this result in significantly lower system emi compared to the typical narrow band signal produced by oscillators and most frequency generators. lowering emi by increasing a signal?s bandwidth is called ?spread spectrum clock generation?. applications the p2041a is targeted towards the embedded controller market and pc peripheral markets including scanners, mfp?s, printers, pda, ia , and gps devices. block diagram xin modout vss frequency divider feedback divider modulation phase detector loop filter vco output divider pll vdd sson sr0 sr1 crystal oscillator xout
january 2006 p2041a rev 0.1 versatile emi reduction ic 2 of 9 notice: the information in this document is subject to change without notice. sson modout pin configuration pin description pin# pin name type description 1 xin/clk i connect to crystal or externally generated clock signal. 2 xout i connect to crystal. no connect if externally generated clock signal is used. 3 sr1 i digital logic input used to select spreading range (see table 1). this pin has an internal pull-up resistor. 4 vss p ground connection. connect to system ground. 5 sson i digital logic input used to enable spread spectrum function (active low). spread spectrum function enable when low. this pin has an internal pull-low resistor. 6 modout o spread spectrum clock output. 7 sr0 i digital logic input used to select spreading range (see table 1). this pin has an internal pull-up resistor. 8 vdd p connect to +3.3v or +5.0v table 1 - spread range selection sr1 sr0 spreading range modulation rate 0 0 +/- 1.50% (fin/40)*34.72 khz 0 1 +/- 2.50% (fin/40)*34.72 khz 1 0 +/- 0.50% (fin/40)*34.72 khz 1 1 +/- 1.00% (fin/40)*34.72 khz xout sr0 1 2 3 4 5 6 7 8 p2040c xin/clk sr1 vss vdd 1 2 3 4 5 6 7 8 p2041a sr1 vdd
january 2006 p2041a rev 0.1 versatile emi reduction ic 3 of 9 notice: the information in this document is subject to change without notice. spread spectrum selection table 1 illustrates the possible spread spectrum options. the optimal setting should minimize system emi to the fullest without affecting system performance. the spreading is described as a percentage deviation of the center frequency ( note: the center frequency is the frequency of the external refere nce input on xin/clk, pin 1). example of a typical printer or scanner application that operates on a clock frequency of 40mhz: a spreading selection of sr1=1 and sr0=1 provides a perce ntage deviation of +/-1.00%* (see table 1) of center frequency. this results in the frequency on modout being sw ept from 40.40mhz to 39.60mhz at a modulation rate of (40/40)*34.72 = 34.72khz (see table 1). this particular exam ple (see figure below) given here is a common emi reduction method for scanners and has already been implement ed by most of the leading manufacturers. note: spreading range selection varies from different system manufactur ers and their designs. the spreading range of p2041a can be se t to +/-2.5% when working with certain scanner model. p2041a application schematic for flat-bed scanner 1 2 3 4 8 7 6 5 vdd sr0 modout sson vss sr1 xout xin/clk p2041a vdd modulated 40mhz signal with 1.00% deviation and modulation rate of 34.72khz. this signal is connected back to the clock crystal input pin of the system asic. note: the above schematic indicates the exact setting of this example: default setting (no connection on pin 3, 7 and 5) 40mhz 0.1f
january 2006 p2041a rev 0.1 versatile emi reduction ic 4 of 9 notice: the information in this document is subject to change without notice. absolute maximum ratings symbol parameter rating unit vdd, v in voltage on any pin with respect to ground -0.5 to +7.0 v t stg storage temperature -65 to +125 c t a operating temperature -40 to +85 c t s max. soldering temperature (10 sec) 260 c t j junction temperature 150 c t dv static discharge voltage (as per jedec std22- a114-b) 2 kv note: these are stress ratings only and are not implied for functional use. exposure to absolute maximum ratings for prolonged periods of time may affect device reliability. dc electrical characteristics (test condition: all parameters are measured at ro om temperature (+25c) unless otherwise stated) symbol parameter min typ max unit ( for 3.3v supply voltage) vss ?0.3 - 0.8 v il input low voltage ( for 5v supply voltage) - - 1.5 v ( for 3.3v supply voltage ) 2.0 - vdd + 0.3 v ih input low voltage ( for 5v supply voltage) 3.5 - - v ( for 3.3v supply voltage) - - -35 i il input low current (pull-up resistor on inputs sr0, sr1) ( for 5v supply voltage) - - -100 a ( for 3.3v supply voltage) - - 35 i ih input high current (pull-down resistor on input sson ) ( for 5v supply voltage) - - 100 a i xol xout output low current (v xol @ 0.4v, vdd = 3.3v) - 3 - i xoh xout output high current ( v xoh @ 2.5v, vdd = 3.3v) - 3 - ma ma (vdd=3.3v, i ol = 20 ma) - - 0.4 v ol output low voltage (vdd=5v, i ol = 20 ma) - - 0.5 v (vdd=3.3v, i oh = 20 ma) 2.5 - - v oh output high voltage (vdd=5v, i oh = 20 ma) 4.5 - - v i dd static supply current - 1.0 - ma 3.3v and 15pf loading - - 22 i cc dynamic supply current 5v and 15pf loading - - 35 ma vdd operating volt age 2.7 3.3 5.5 v
january 2006 p2041a rev 0.1 versatile emi reduction ic 5 of 9 notice: the information in this document is subject to change without notice. ac electrical characteristics symbol parameter min typ max unit f in input frequency 25 40 60 mhz t lh * output rise time ( measured at 0.8v to 2.0v ) 0.7 1.0 1.3 ns t hl * output fall time ( measured at 2.0 to 0.8v ) 0.6 0.8 1.0 ns t jc jitter (cycle to cycle) - 360 - ps t d output duty cycle 45 50 55 % *t lh and t hl are measured into a capacitive load of 15pf
january 2006 p2041a rev 0.1 versatile emi reduction ic 6 of 9 notice: the information in this document is subject to change without notice. package information 8-lead (150-mil) soic package d e h d a1 a2 a l c b e dimensions inches millimeters symbol min max min max a1 0.004 0.010 0.10 0.25 a 0.053 0.069 1.35 1.75 a2 0.049 0.059 1.25 1.50 b 0.012 0.020 0.31 0.51 c 0.007 0.010 0.18 0.25 d 0.193 bsc 4.90 bsc e 0.154 bsc 3.91 bsc e 0.050 bsc 1.27 bsc h 0.236 bsc 6.00 bsc l 0.016 0.050 0.41 1.27 0 8 0 8
january 2006 p2041a rev 0.1 versatile emi reduction ic 7 of 9 notice: the information in this document is subject to change without notice. e h a a1 a2 d b c l e 8-lead thin shrunk small outline package (4.40-mm body) dimensions inches millimeters symbol min max min max a 0.043 1.10 a1 0.002 0.006 0.05 0.15 a2 0.033 0.037 0.85 0.95 b 0.008 0.012 0.19 0.30 c 0.004 0.008 0.09 0.20 d 0.114 0.122 2.90 3.10 e 0.169 0.177 4.30 4.50 e 0.026 bsc 0.65 bsc h 0.252 bsc 6.40 bsc l 0.020 0.028 0.50 0.70 0 8 0 8
january 2006 p2041a rev 0.1 versatile emi reduction ic 8 of 9 notice: the information in this document is subject to change without notice. ordering information part number marking package configuration temperature range p2041a -08st p2041a 8-pin soic,tube commercial p2041a -08sr p2041a 8-pin soic, tape and reel commercial p2041af-08st p2041af 8-pin soic, tube, pb free commercial p2041af-08sr p2041af 8-pin soic, tape and reel, pb free commercial p2041ag-08st p2041ag 8-pin soic, tube, green commercial p2041ag-08sr p2041ag 8-pin soic, tape and reel, green commercial i2041a-08st i2041a 8-pin soic, tube industrial i2041a-08sr i2041a 8-pin soic, tape and reel industrial i2041af-08st i2041af 8-pin soic, tube, pb free industrial i2041af-08sr i2041af 8-pin soic, tape and reel, pb free industrial i2041ag-08st i2041ag 8-pin soic, tube, green industrial i2041ag-08sr i2041ag 8-pin soic, tape and reel, green industrial p2041a-08tt p2041a 8-pin tssop, tube commercial p2041a-08tr p2041a 8-pin tssop, tape and reel commercial p2041af-08tt p2041af 8-pin tssop, tube, pb free commercial p2041af-08tr p2041af 8-pin tssop, tape and reel, pb free commercial p2041ag-08tt p2041ag 8-pin tssop, tube, green commercial p2041ag-08tr p2041ag 8-pin tssop, tape and reel, green commercial i2041a-08tt i2041a 8-pin tssop, tube industrial i2041a-08tr i2041a 8-pin tssop, tape and reel industrial i2041af-08tt i2041af 8-pin tssop, tube, pb free industrial i2041af-08tr i2041af 8-pin tssop, tape and reel, pb free industrial i2041ag-08tt i2041ag 8-pin tsso p, tube, green industrial i2041ag-08tr i2041ag 8-pin tssop, tape and reel, green industrial device ordering information p2041a f-08 xx licensed under us patent nos 5,488,627 and 5,631,920. sr - soic, t/r tt ? tssop, tube tr - tssop, t/r st ? soic , tube device number flow: p = commercial temperature range (0c to 70c) i = industrial temperature range (-40c to 85c) pin count deviation (%) and spread option identifier f =lead free and and rohs compliant part g = green
january 2006 p2041a rev 0.1 versatile emi reduction ic 9 of 9 notice: the information in this document is subject to change without notice. ? copyright 2003 alliance semiconductor corporation. all rights reserved. our three-point logo, our name and intelliwatt are trademarks or registered trademarks of alliance. all other brand and product names may be the trademarks of their respective companies. alliance reserves the right to make ch anges to this document and its products at any time without notice. alliance assumes no responsibility for any errors t hat may appear in this document. the data contained herein represents alliance's best data and/or estimate s at the time of issuance. alliance rese rves the right to change or correct this data at any time, without notice. if the product described herein is under development, significant changes to these specifications are possible. the information in this product data sheet is intended to be general descriptive information for potential customers and users, and is not in tended to operate as, or provide, any guarantee or warrantee to any user or customer. alliance does not assume any responsibility or lia bility arising out of the applic ation or use of any product described herein, and disclaims any express or implied warrant ies related to the sale and/or use of alliance products including liability or warranties related to fitness for a particular purpose, mercha ntability, or infringement of any intellec tual property rights, except as express agreed to in alliance's terms and conditions of sale (which are available from alliance). all sales of alliance products are made exclusively according to alliance's terms and conditions of sale. the purchase of products from alliance does not convey a license under any pa tent rights, copyrights; mask works rights, trademarks, or any other intellectual property rights of alli ance or third parties. alliance does not aut horize its products for use as critical components in life-supporting systems where a malfunction or fa ilure may reasonably be expected to result in significant injury to the user, and the inclusion of alliance products in such life-supporting systems implies that the manufacturer assumes all risk of such use and agrees to indemnify alliance against all claims arising from such use. alliance semiconductor corporation 2575 augustine drive, santa clara, ca 95054 tel# 408-855-4900 fax: 408-855-4999 www.alsc.com copyright ? alliance semiconductor all rights reserved part number: p2041a document version: 0.1 note: this product utilizes us patent # 6,646,463 impedance emulator patent issued to alliance semiconductor, dated 11-11-2003
|
