P2811A/b and p2812a/b and p 2814a/b low power emi reduction ic ?2010 scillc. all rights reserved. publication order number: june 2011 C rev. 2 p2811/d features fcc approved method of emi attenuation provides up to 15db emi reduction generates a 1x, 2x and 4x low emi spread spectrum clock of the input frequency o 1x: P2811A/b o 2x: p2812a/b o 4x: p2814a/b optimized for input frequency range from 10mhz to 40mhz internal loop filter minimizes external components and board space selectable spread options: o down spread and center spread 8 frequency deviation selections: o 0.625% to -3.5% low inherent cycle-to-cycle jitter 3.3v operating voltage cmos/ttl compatible inputs and outputs. pin-out compatible with cypress cy25811, cy25812 and cy25814 available in 8-pin soic package product description the p28xx devices are versatile spread spectrum frequency modulators designed specifically for a wi de range of input clock frequencies from 10mhz to 40mh z. refer to input/output frequency range selection table. the p28xx can generate an emi reduced clock from crystal, ceramic resonator, or system clock. the p2 8xx-a and the p28xx-b offer various combinations of spread options and percentage deviations. refer to frequency deviation and spread selection table . these combinations include down and center spread, and percentage deviation range from 0.625% to -3.5%. the p28xx reduces electromagnetic interference (emi ) at the clock source, allowing system wide reduction of emi of downstream clock and data dependent signals. the p28xx allows significant system cost savings by reducing the number of circuit board layers, ferrit e beads, shielding, and other passive components that are traditionally required to pass emi regulations. the p28xx modulates the output of a single pll in o rder to spread the bandwidth of a synthesized clock, a nd more importantly, decreases the peak amplitudes of its harmonics. this results in significantly lower syst em emi compared to the typical narrow band signal produced by oscillators and most frequency generators. lowering emi by increasing a signals bandwidth is called sprea d spectrum clock generation. the p28xx uses the most efficient and optimized modulation profile approved by the fcc and is implemented in a proprietary all-digital method. applications the p28xx is targeted towards emi management for memory and lvds interfaces in mobile graphic chipse ts and high-speed digital applications such as pc peri pheral devices, consumer electronics, and embedded control ler systems.
P2811A/b and p2812a/b and p2814a/b . rev. 2 | page 2 of 6 | www.onsemi.com block diagram pin configuration pin description pin# pin name type description 1 xin / clkin i crystal connection or external cloc k input. 2 vss p ground to entire chip. 3 d_c i digital logic input used to select down (low) or ce nter (high) spread options. (refer to frequency deviation and spread selection table ). this pin has an internal pull-up resistor. 4 srs i spread range select. digital logic input used to se lect frequency deviation (refer to frequency deviation and spread selection table ). this pin has an internal pull-up resistor. 5 modout o spread spectrum clock output. 6 frs i frequency range select. digital logic input used to select input frequency range (refer to input/output frequency range selection table). this pin has an internal pull-up resistor. 7 vdd p power supply for the entire chip. 8 xout o crystal connection. if using an external reference, this pin must be left unconnected. modout 1 2 3 4 5 6 7 8 frs xout xin / clkin vss d_c srs vdd P2811A/b p2812a/b p2814a/b xin / clkin crystal oscillator frequency divider feedback divider r modulation phase detector loop filter vco output divider modout pll vdd d_c srs frs xout vss
P2811A/b and p2812a/b and p2814a/b . rev. 2 | page 3 of 6 | www.onsemi.com input/output frequency range selection table frs (pin 6) part number modulation rate p2811 (1x) p2812 (2x) p2814 (4x) input (mhz) output (mhz) input (mhz) output (mhz) input (mhz) output (mhz) 0 10-20 10-20 10-20 20-40 10-20 40-80 input frequen cy / 448 1 20-40 20-40 20-40 40-80 20-40 80-160 input freque ncy / 896 output frequency deviation and spread selection tab le part number d_c (pin 3) srs (pin 4) frequency deviation 1 (%) fs=0 fs=1 10/20/40 (mhz) 20/40/80 (mhz) 20/40/80 (mhz) 40/80/160 (mhz) p28xxa 0 0 -3 -2.5 -2.7 -2.6 0 1 -3.7 -3.4 -3.8 -3.6 1 0 1.5 1.2 1.5 1.3 1 1 1.8 1.6 1.9 1.8 p28xxb 0 0 -1.7 -1.0 -1.5 -1.4 0 1 -2.0 -1.5 -2.0 -1.9 1 0 0.75 0.6 0.8 0.7 1 1 1.0 0.75 1.0 0.9 note: 1. frequency deviation given in the table is for the output frequency range covering p2811x / 12 x / 14x. absolute maximum ratings symbol parameter rating unit v dd , v in voltage on any pin with respect to ground -0.5 to +4.6 v t stg storage temperature -65 to +125 c t s max. soldering temperature (10 sec) 260 c t j junction temperature 150 c t dv static discharge voltage(as per jedec std 22- a114 -b) 2 kv note: these are stress ratings only and are not imp lied for functional use. exposure to absolute maxim um ratings for prolonged periods of time may affect device reliability.
P2811A/b and p2812a/b and p2814a/b . rev. 2 | page 4 of 6 | www.onsemi.com operating conditions symbol parameter min max unit vdd supply voltage 3.0 3.6 v t a operating temperature -40 +85 c c l load capacitance 15 pf c in input capacitance 7 pf dc electrical characteristics symbol parameter min typ max unit v il input low voltage vss C 0.3 0.8 v v ih input high voltage 2 v dd + 0.3 v i il input low current (inputs d_c, srs and frs are pulled high internally ) -50 a i ih input high current 50 a i xol xout output low current (v xol @ 0.4v, v dd = 3.3v) 3 ma i xoh xout output high current (v xoh @ 2.5v, v dd = 3.3v) 3 ma v ol output low voltage (v dd = 3.3v, i ol = 15ma) 0.4 v v oh output high voltage (v dd = 3.3v, i oh = -15ma) 2.5 v i cc dynamic supply current (unloaded output) 8 24 ma i dd static supply current , standby mode (clkin pulled to gnd) 4.5 ma vdd operating voltage 3.0 3.3 3.6 v t on power up time (first locked clock cycle after powe r up) 500 s z out clock out impedance 26 ac electrical characteristics symbol parameter min typ max unit f in input frequency for p2811/12/13/14 a/b 10 40 mhz f out output frequency for P2811A/b 10 40 mhz output frequency for p2812a/b 20 80 mhz output frequency for p2814a/b 40 160 mhz t lh 1 output rise time (measured at 0.8v to 2.0v) 0.4 0. 5 0.7 ns t hl 1 output fall time (measured at 2.0v to 0.8v) 0.5 0. 6 0.8 ns t jc cycle-to-cycle jitter (unloaded output) 250 ps t d output duty cycle 45 50 55 % note: 1. t lh and t hl are measured into a capacitive load of 15pf
P2811A/b and p2812a/b and p2814a/b . rev. 2 | page 5 of 6 | www.onsemi.com package information 8-pin soic package d e h d a1 a2 a q l c b e 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 0.193 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 note: controlling dimensions are millimeters. soic: 0.074 grams unit weight.
P2811A/b and p2812a/b and p2814a/b . rev. 2 | page 6 of 6 | www.onsemi.com ordering code part number marking package type temperature p2811bf-08sr abu 8-pin soic, tape & reel, pb free 0 c to +70c i2811bf-08sr abv 8-pin soic, tape & reel, pb free - 40c to +85c p2814bg-08sr acd 8-pin soic, tape & reel, pb free 0 c to +70c a microdot placed at the end of last row of marki ng or just below the last row toward the center of package indicates pb-free licensed under us patent #5,488,627, #6,646,463 and #5,631,920. on semiconductor and are registered trademarks of semiconductor componen ts industries, llc (scillc). scillc reserves the ri ght to make changes without further notice to any products herein. sci llc makes no warranty, representation or guarantee regarding the suitability of its products for any p articular purpose, nor does scillc assume any liability arisi ng out of the application or use of any product or circuit, and specifically disclaims any and all lia bility, including without limitation special, consequential or incidental damages. typical parameters which may be provided in scillc data sheets and/or specifications can and do vary in different applica tions and actual performance may vary over time. al l operating parameters, including typicals must b e validated for each customer application by customer 's technical experts. scillc does not convey any l icense under its patent rights nor the rights of ot hers. scillc products are not designed, intended, or auth orized for use as components in systems intended fo r surgical implant into the body, or other applicat ions intended to support or sustain life, or for any oth er application in which the failure of the scillc p roduct could create a situation where personal inju ry or death may occur. should buyer purchase or use scillc pro ducts for any such unintended or unauthorized appli cation, buyer shall indemnify and hold scillc and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs , damages, and expenses, and reasonable attorney fe es arising out of, directly or indirectly, any claim of person al injury or death associated with such unintended or unauthorized use, even if such claim alleges tha t scillc was negligent regarding the design or manufacture o f the part. scillc is an equal opportunity/affirmat ive action employer. u.s patent pending; timing-sa fe and active bead are trademarks of pulsecore semicon ductor, a wholly owned subsidiary of on semiconduct or. this literature is subject to all applicable copyright laws and is not for resale in any manner. publication ordering 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: orderlit@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 literature: http://www.onsemi.com/orderlit for additional information, please contact your local sales representative
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