september 2003 asm3p5811b rev 1.0 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. features fcc approved method of emi attenuation. generates a 1x low emi spread spectrum clock of the input frequency. input frequency range: 10mhz ? 20mhz. internal loop filter minimizes external components and board space. frequency deviation: -2.5% low inherent cycle-to-cycle jitter. 3.3v operating voltage. ttl or cmos compatible inputs and outputs. ultra-low power cmos design. o tbd ma @ 3.3v, 16.6mhz pinout compatible with cypress cy25811. products are available for industrial temperature range. available in 8-pin soic and tssop. product description the asm3p5811b is a versatile spread spectrum frequency modulator designed specifically for input clock frequencies in the range of 10mhz - 20mhz. the asm3p5811b can generate an emi reduced clock from crystal, ceramic resonator, or system clock. the asm3p5811b offers a percentage deviation of ?2.5%. the asm3p5811b reduces electromagnetic interference (emi) at the clock source, allowing system wide reduction of emi of down stream clock and data dependent signals. the asm3p5811b allows significant system cost savings by reducing the number of circuit board layers ferrite beads, shielding and other passive components that are traditionally required to pass emi regulations. the asm3p5811b uses the most efficient and optimized modulation profile approved by the fcc and is implemented in a proprietary all digital method. the asm3p5811b 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 results 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 asm3p5811b is targeted towards emi management for high speed digital applications such as pc peripheral devices, consumer electronics and embedded controller systems. block diagram vss xin crystal oscillator frequency divider feedback divider modulation phase detector loop filter vco output divider modout pll vdd xout
asm3p5811b low power emi reduction ic 2 of 7 notice: the information in this document is subject to change without notice. 1 2 3 4 5 6 7 8 asm3p5811b xin vss nc nc modout n c vdd xout pin configuration pin description pin# pin name type description 1 xin i crystal connection or external refere nce frequency input. this pin has dual functions. it can be connected to either an external crystal or an external reference clock. 2 vss p ground to entire chip. 3 nc no connect. 4 nc no connect. 5 modout o spread spectrum low emi output. 6 nc no connect. 7 vdd p power supply for the entire chip (3.3v). 8 xout i crystal connection. if using an external reference clock, this pin must be left unconnected.
asm3p5811b low power emi reduction ic 3 of 7 notice: the information in this document is subject to change without notice. absolute maximum ratings symbol parameter rating unit vdd, vin voltage on any pin with respect to gnd -0.5 to + 7.0 v tstg storage temperature -65 to +125 c ta operating temperature 0 to 70 c note: these are stress ratings only and functional oper ation is not implied. exposure to absolute maximum ratings for extended periods may affect device reliability. dc electrical characteristics symbol parameter min typ max unit v il input low voltage gnd ? 0.3 - tbd v v ih input high voltage tbd - v dd + 0.3 v i il input low current tbd a i ih input high current tbd a i xol xout output low current (@0.4v, v dd =3.3v) tbd ma i xoh xout output high current (@ 2.5v, v dd =3.3v) tbd ma v ol output low voltage (v dd = 3.3v, i ol = 4ma) tbd v v oh output high voltage (v dd = 3.3v, i oh = 4ma) tbd v i cc dynamic supply current normal mode (3.3v and 10pf loading) tbd ma i dd static supply current standby mode tbd a v dd operating voltage tbd 3.3 tbd v t on power up time (first locked cloc k cycle after power up) - tbd - ms z out clock out impedance - tbd - ?
asm3p5811b low power emi reduction ic 4 of 7 notice: the information in this document is subject to change without notice. ac electrical characteristics symbol parameter min typ max unit xin input frequency 10 16.6 20 mhz modout output frequency 10 16.6 20 mhz tlh* output rise time (measu red at 0.8v to 2.0v) tbd ns thl* output fall time (measured at 2.0v to 0.8v) tbd ns tjc jitter (cycle to cycle) - - tbd ps td output duty cycle - tbd - % tlh and thl are measured into a capacitive load of 15pf
asm3p5811b low power emi reduction ic 5 of 7 notice: the information in this document is subject to change without notice. d e h d a1 a2 a l c b e package information 8-pin soic symbol dimensions in inches dimensions in millimeters min max min max a 0.057 0.071 1.45 1.80 a1 0.004 0.010 0.10 0.25 a2 0.053 0.069 1.35 1.75 b 0.012 0.020 0.31 0.51 c 0.004 0.01 0.10 0.25 d 0.186 0.202 4.72 5.12 e 0.148 0.164 3.75 4.15 e 0.050 bsc 1.27 bsc h 0.224 0.248 5.70 6.30 l 0.012 0.028 0.30 0.70 0 8 0 8
asm3p5811b low power emi reduction ic 6 of 7 notice: the information in this document is subject to change without notice. e h a a1 a2 d b c l e 8-pin tssop dimensions in inches dimensions in millimeters symbol min max min max a 0.047 1.10 a1 0.002 0.006 0.05 0.15 a2 0.031 0.041 0.80 1.05 b 0.007 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 0.244 0.260 6.20 6.60 l 0.018 0.030 0.45 0.75 0 8 0 8
asm3p5811b low power emi reduction ic 7 of 7 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 2595, augustine drive, santa clara, ca 95054 tel# 408-855-4900 fax: 408-855-4999 www.alsc.com copyright ? alliance semiconductor all rights reserved preliminary information part number: asm3p5811b document version: v1.0
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