asm3p2111b peak emi reducing solution ?2010 scillc. all rights reserve d. publication order number: january 2010 C rev. 1 asm3p2111 /d features generates an emi optimized clock at the output. input frequency: 25mhz. frequency outputs: o 60mhz (unmodulated) o 2 x 48mhz (unmodulated) o 66.6mhz (modulated): - 1.7% down spread modulation rate: 30khz. supply voltage range: 3.3v 0.3v. available in 8 - pin soic package. commercial and industrial temperature range. rohs compliant product description the asm3p2111b is a versatile spread spectrum frequency modulator that reduces electromagnetic interference (emi) at the clock source. the asm3p2111b allow s significant system cost savings by reducing the number of circuit board layers and shielding that are required to pass emi regulations. the asm3p2111b modulates the output of pll in order to spread the bandwidth of a synthesized clock, thereby decreasing the peak amplitudes of its harmonics. this results in significantly lower system emi compared to the typical narrow band signal produced by oscillators and most clock generators. lowering emi by increasing a signals bandwidth is called spread spectrum cl ock generation. applications asm3p2111b is targeted towards emi management for high speed digital applications such as pc peripheral devices, consumer electronics and embedded controller systems. block diagram crystal oscillator 66.6 mhz modulated xin / clkin xout v ss 48 mhz_2 60 mhz 48 mhz_1 pll1 pll2 48 mhz_1 v dd
asm3p2111b rev. 1 | page 2 of 8 | www.onsemi.com pin configuration pin description pin # pin name type description 1 xin / clkin i connection to crystal 2 xout o connection to crystal 3 v dd p power supply for the analog and digital blocks (+3.3v) 4 60mhz o clock output - 1 60mhz un - modulated 5 48mhz_2 o cloc k output - 2 48mhz_2 un - modulated 6 48mhz_1 o clock output - 3 48mhz_1 un - modulated 7 66.6mhz o clock output - 4 66.6mhz modulated 8 v ss p ground to entire chip. connect to system ground 60mhz v ss xout xin/ clkin v dd 8 7 6 5 1 2 3 4 asm3p2111b 48mhz_2 48mhz_1 66.6mhz
asm3p2111b rev. 1 | page 3 of 8 | www.onsemi.com absolute maximum ratings symbol parameter rating unit v dd , v in voltag e on any pin with respect to ground - 0.5 to +4.6 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 s td22 - a114 - b) 2 kv note: these are stress ratings only and are not implied for functional use. exposure to absolute maximum ratings for prolonge d periods of time may affect device reliability. operating conditions symbol parameter condition / description min typ max unit v dd supply voltage 3.3v 0.3v 3 3.3 3.6 v f xin crystal resonator frequency 25 - - mhz c l output driver load capacitance - - 15 pf
asm3p2111b rev. 1 | page 4 of 8 | www.onsemi.com dc electrical characteristics ac electrical characteristics parameter symbol conditions / description min typ max unit rise time t r v o = 0.8v to 2.0v; c l = 15pf 300 800 900 ps fall time t f v o = 2.0v to 0.8v; c l = 15pf 360 800 900 ps clock duty c ycle ratio of pulse width (as measured from rising edge to next falling edge at v dd /2) to one clock period 45 - 55 % note: 1. c l = 15 pf, input clock frequency = 25mhz . parameter symbol conditions / description min typ max unit overall supply current, dynamic i dd v dd = 3.3v, f clk = 25mhz, c l = 15pf 41 48 62 ma supply current, static i ddl v dd = 3.3v, clock input = 0 20 25 35 ma all input pins high - level input voltage v ih v dd = 3.3v 2.0 - v dd +0.3 v low - level input voltage v il v dd =3.3v v ss - 0.3 - 0.8 v high - level input current i ih - 1 - 1 a low - level input current (pull - up) i il - 20 - 36 - 80 a high - level output source current i xoh v dd = v (xin) = 3.3v, v o = 0.4v - 3 - ma low - level output sink current i xol v dd = 3.3v, v (xin) = v o = 2.5v - 3 - ma cl ock outputs high - level output source current i oh v o = 2.5v - - 20 - ma low - level output sink current i ol v o = 0.4v - 23 - ma output impedance z oh v o = 0.5 v dd ; output driving high - 29 - z ol v o = 0.5 v dd ; output driving low - 27 -
asm3p2111b rev. 1 | page 5 of 8 | www.onsemi.com typical crystal oscillator circuit typical crystal specificatio ns fundamental at cut parallel resonant crystal nominal frequency 25mhz frequency tolerance 50ppm or better at 25c operating temperature range - 25c to +85c storage temperature - 40c to +85c load capacitance 18pf shunt capacitance 7pf maximum es r 25 r1 = 510? c1 = 18 pf c2 = 18 pf crystal
asm3p2111b rev. 1 | page 6 of 8 | www.onsemi.com package information 8 - lead (150 - mil) soic package symbol dimensions inches millimeters 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 0.1 93 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 d e h d a1 a2 a l c b e
asm3p2111b rev. 1 | page 7 of 8 | www.onsemi.com ordering codes part number marking package configuration temperature range asm3p2111bf - 08st 3p2111bf 8 - pin soic tube, pb free comm ercial asm3p2111bf - 08sr 3p2111bf 8 - pin soic tape & reel, pb free commercial asm3i2111bf - 08st 3i2111bf 8 - pin soic tube, pb free industrial asm3i2111bf - 08sr 3i2111bf 8 - pin soic tape & reel, pb free industrial asm3p2111bg - 08st 3p2111bg 8 - pin soic tube , gr een commercial asm3p2111bg - 08sr 3p2111bg 8 - pin soic tape & reel , green commercial asm3i2111bg - 08st 3i2111bg 8 - pin soic tube , green industrial asm3i2111bg - 08sr 3i2111bg 8 - pin soic tape & reel , green industrial ordering information a s m 3 p 2 1 1 1 b f - 0 8 s r licensed under us patent #5,488,627, #6,646,463 and #5,631,920. o = sot u = msop s = soic e = tqfp t = tssop l = lqfp a = ssop u = msop v = tvsop p = pdip b = bga d = qsop q = qfn x = sc - 70 device pin count x= automotive i= industrial p or n/c = commercial ( - 40c to +125c) ( - 40c to +85c) (0c to +70c) 1 = reserved 6 = power management 2 = non pll based 7 = power m anagement 3 = emi reduction 8 = power management 4 = ddr support products 9 = hi performance 5 = std zero delay buffer 0 = reserved on semiconductor mixed signal product part number f = lead free and rohs compliant part g = green package, lead free, and r ohs r = tape & reel, t = tube or tray
asm3p2111b note: th is product utilizes us patent # 6,646,463 impedance emulator patent issued to pulsecore semiconductor, dated 11 - 11 - 2003 . on semiconductor and are registered trademarks of semiconducto r components industries, llc (scillc). scillc reserves the right to make changes without further notice to any products herein. scillc makes no warranty, representation or guarantee regarding the suitabili ty of its products for any particular purpose, nor does scillc assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages. typical parameters which may b including typicals must be publication orderi ng information literature fulfillment: literature distribution center for on semiconductor p.o. box 5163, denver, colorado 80217 usa phone: 303 - 675 - 2175 or 800 - 344 - 3860 toll free usa/canada fax: 303 - 675 - 2176 or 800 - 344 - 3867 toll free usa/canada email: ord erlit@onsemi.com n. american technical support : 800 - 282 - 9855 toll free usa/canada europe, middle east and africa technical support: phone: 421 33 790 2910 japan customer focus center phone: 81 - 3 - 5773 - 3850 on semiconductor website: www.onsemi.com order li terature: http://www.onsemi.com/orderlit for additional information, please contact your local sales representative
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