alliance semiconductor 2595, augustine drive ? santa clara ? ca 95054 ? tel 408 855 4900 ? fax 408 855 4999 ? www.alsc.com november 2003 as80m2180 rev 1.1 notice: the information in this document is subject to change without notice. peak reducing emi solution features ? generates an emi optimized clocking signal at the output. ? selectable output frequency range. ? single 1.25% or 2.4% down spread output. ? integrated loop filter components. ? operates with a 3.3v supply. ? low-power cmos design. ? available in 8-pin soic and 8-pin tssop packages. product description the as80m2180 is a versatile spread spectrum frequency modulator designed specifically for a wide range of clock frequencies. the as80m2180 reduces electromagnetic interference (emi) at t he clock source, allowing system wide reduction of emi of down stream clock and data dependent signals. the as80m2180 allows significant system cost savings by reducing the number of circuit board layers and shielding that are traditionally required to pass emi regulations. the as80m2180 modulates the output of a single 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 signal?s bandwidth is called spread spectrum clock generation. the as80m2180 uses the most efficient and optimized modulation profile approved by the fcc and is implemented by using a proprietary all-digital method. applications the as80m2180 is targeted towards notebook lcd displays, other displays using an lvds interface, pc peripheral devices and embedded systems. key specifications description specification supply voltages v dd = 3.3v 5% frequency range 6 mhz 30 mhz cycle-to-cycle jitter 325 ps (typical) selectable spread percentage -1.25% or ?2.4% output duty cycle 40/60% (worst case) output rise and fall time 5ns (maximum) simplified block diagram pin diagram x1 x2 3.3v spread spectrum output (emi suppressed) 1 2 3 4 5 6 7 8 clkin / x1 nc / x2 gnd clkout nc vdd fs1 ss% as80m2180
peak reducing emi solution 2 of 7 november 2003 as80m2180 rev 1.1 notice: the information in this document is subject to change without notice. modulation width selection ss% output 0 fin fout fin ? 1.25% 1 fin fout fin ? 2.4% frequency range selection fs1 modulation rate 0 6 fin 10 1 18 fin 30 pin description pin# pin name type description 1 clkin or x1 i crystal connection or external refe rence frequency input. this pin has dual functions. it can be connected to either an external crystal or an external reference clock. 2 nc or x2 o crystal connection. connection for an external crystal. if using an external reference, this pin must be left unconnected. 3 gnd g ground to entire chip. 4 ss% i modulation width selection. when spread spectrum feature is turned on, this pin is used to select the amount of variation and peak emi reduction that is desired on the output signal. internal pull-up resistor. 5 clkout o output modulated frequency. copy of the un-modulated input clock. 6 vdd p power supply for the entire chip (3.3v). 7 fs1 i frequency selection bit 1. this pi n selects the frequency range of operation. ( refer to the frequency range selection table ). this pin has an internal pull-up resistor. 8 nc - no connect.
peak reducing emi solution 3 of 7 november 2003 as80m2180 rev 1.1 notice: the information in this document is subject to change without notice. absolute maximum ratings symbol parameter rating unit v dd , v in voltage on any pin with respect to gnd -0.5 to + 7.0 v t stg storage temperature -65 to +125 c t a operating temperature 0 to 70 c note: these are stress ratings only and functional operation 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 - 0.8 v v ih input high voltage 2.0 - v dd + 0.3 v i il input low current (pull- up resistors on inputs ss%, fs1) - - -27 a i ih input high current - - 18 a i xol x out output low current (@ 0.4v, v dd = 3.3v) - 3 - ma i xoh x out output high current (@2.5v, v dd = 3.3v) - 4 - ma v ol output low voltage (v dd = 3.3v, i ol = 4ma) - - 0.4 v v oh output high voltage (v dd = 3.3v, i oh = 4ma) 2.5 - - v i cc dynamic supply current normal mode (3.3v and 10pf loading) 8 21 35 ma i dd static supply current standby mode - 0.8 - a v dd operating voltage 2.8 3.3 3.7 v t on power up time (first locked clock cycle after power up) - 0.18 - ms z out clock output impedance - 50 - ? ac electrical characteristics symbol parameter min typ max unit clkin input frequency 6 - 30 mhz clkout output frequency 6 - 30 mhz t lh * output rise time (measured at 0.8v to 2.0v) 1.2 1.3 1.4 ns t hl * output fall time (measured at 2.0v to 0.8v) 0.8 0.9 1.0 ns t jc jitter (cycle to cycle) - - 325 ps t d output duty cycle 45 50 55 % *t lh and t hl are measured into a capacitive load of 15pf
peak reducing emi solution 4 of 7 november 2003 as80m2180 rev 1.1 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
peak reducing emi solution 5 of 7 november 2003 as80m2180 rev 1.1 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
peak reducing emi solution 6 of 7 november 2003 as80m2180 rev 1.1 notice: the information in this document is subject to change without notice. ordering codes ordering number marking package type quantity per reel temperature as80m2180-08st as80m2180 8-pin soic, tube 0 c to 70c AS80M2180-08SR as80m2180 8-pin soic, tape and reel 2500 0 c to 70c as80m2180-08tt as80m2180 8-pin tssop, tube 0 c to 70c as80m2180-08tr as80m2180 8-pin tssop, tape and reel 2500 0 c to 70c licensed under us patent #5,488,627, # 6,646,463 and #5,631,920.
peak reducing emi solution 7 of 7 november 2003 as80m2180 rev 1.1 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 ma y be the trademarks of their respective companies. alliance reserves the right to make changes to this document and its produc ts at any time without notice. alliance assumes no responsibility for any errors that may appear in this document. the data c ontained herein represents alliance's best data and/or estimates at the time of issuan ce. alliance reserves the right to change or correct this data at any time, without notice. if the product described herein is under deve lopment, significant changes to these speci fications are possibl e. the information in this product data sheet is intende d to be general descriptive information for po tential customers and users, and is not intende d to operate as, or provide, any guarantee or warrantee to any us er or customer. alliance does not assume any responsibility or liability arising out of the application or use of any product described herein, and di sclaims any express or implied warrantie s related to the sale and/or use of alliance products including lia bility or warranties related to fitness for a particular purpo se, merchantability, or infringement of any intellectual property rights, except as express agreed to in alliance's terms and conditions of sale (which are available from alliance). all sales of alliance produc ts are made exclusively according to alliance's terms and conditions of sale. th e purchase of products from alliance does not convey a license under any patent rights, copyrights; mask works ri ghts, trademarks, or any other in tellectual property rights of alliance or third parties. alli ance does not authorize its products for use as critical components in life-supporting sy stems where a malfunction or failure may reasonably be expected to result in significant injury to the user, and the inclusion of alliance products in such life-support ing 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: as80m2180 document version: v1.1 note: this product utilizes us patent # 6,646,463 impedance emulator patent issued to alliance semiconductor, dated 11-11-2003
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