integrated circuit systems, inc. general description features ics9158-01 block diagram 9158-01 rev b 05/30/97 the ics9158-01 is a low cost frequency generator designed specifically for desktop and notebook pc applications. eight high drive, skew-controlled copies of the cpu clock are avail-able, eliminating the need for an external buffer. each high drive (50ma) output is capable of driving a 30pf load and has a typical duty cycle of 50/50. the cpu clock outputs are skew-controlled to within 250ps. the cpu clocks provide all necessary frequencies for 286, 386, 486 and pentium systems, including support for the latest speeds of processors. the cpu clock offers the unique feature of smooth, glitch- free transitions from one frequency to the next, making this the ideal device to use whenever slowing the cpu speeds. the ics9158-01 makes a gradual transition between frequencies so that it meets the intel cycle-to-cycle timing specification for 486 systems. ? eight skew-free, high drive cpu clock outputs ? up to 100 mhz output at 5v ? 250ps skew between cpu and 2xcpu outputs ? outputs can drive up to 30pf load ? 50ma output drivers ? typical 50/50 duty cycle ? compatible with 486 and pentium cpus ? glitch-free start and stop clock option ? optional power-down mode supports energy star (green) pcs ? on-chip loop filter components ? low power, high speed 0.8cmos technology ? 24-pin pdip or soic package integrated buffer and motherboard frequency generator functionality clock ics9158-01 (mhz) busclk fdclk 14.318 16 24 14.318 cpuclk 2xcpuclk 4,8,30,20,25,33.3,40, or 50 8,16,60,40,50,66.6,80, or 100 ics reserves the right to make changes in the device data identified in this publication without further notice. ics advises its customers to obtain the latest version of all device data to verify that any information being relied upon by the customer is current and accurate.
2 ics9158-01 pin configuration pin descriptions for ics9158-01 24-pin pdip or soic pin number pin name type description 1 cpu2 output cpu clock output 2 x14out - crystal connection 3 x14in - crystal connection 4 vdd - digital power supply (+5v) 5 gnd - digital ground 6 16 mhz output 16 mhz clock output 7 24 mhz output 24 mhz floppy disk/combination i/o clock output 8 cpu3 output cpu clock output 9 agnd - analog ground 10 oe input output enable. tristates all outputs when low. 11 cpu5 output cpu clock output 12 gnd - digital ground 13 cpu7 output cpu clock output 14 cpu6 output cpu clock output 15 s2 input cpu clock frequency select 2 16 avdd - analog power supply (+5v) 17 cpu4 output cpu clock output 18 14.318 mhz output 14.318 mhz clock output 19 gnd - digital ground 20 vdd - digital power supply (+5v) 21 2xcpu output 2x cpu clock output 22 cpu1 output cpu clock output 23 fs1 input cpu clock frequency select #1 24 fs0 input cpu clock frequency select #0
3 ics9158-01 electrical characteristics at 5v absolute maximum ratings avdd, vdd referenced to gnd . . . . . . . . . . . . . . . . 7v operating temperature under bias. . . . . . . . . . . . . . . . 0c to +70c storage temperature . . . . . . . . . . . . . . . . . . . . . . . . . . -40c to +150c voltage on i/o pins referenced to gnd. . . . . . . . . . . gnd -0.5v to vdd +0.5v power dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.5 watts stresses above those listed under absolute maximum ratings may cause permanent damage to the device. this is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operational sections of the specifications is not implied. exposure to absolute maximum rating conditions for extended periods may affect product reliability. v dd = +5v10%, t a =0c to 70c unless otherwise stated note 1: parameter is guaranteed by design and characterization. not 100% tested in production. dc characteristics parameter symbol test conditions min typ max units input low voltage v il 0.8 v input high voltage v ih 2.0 v input low current i il v in =0v -5 5 a input high current i ih v in =v dd -5 5 a output low voltage v ol i ol =20.0ma 0.25 0.4 v output high voltage 1 v oh i oh =-30ma 2.4 3.5 v output low current 1 i ol v ol =0.8v 45 65 ma output high current 1 i oh v oh =2.0v -55 -35 ma supply current i dd no load, 80 mhz 43 65 ma output frequency change over supply and temperature 1 f d with respect to typical frequency 0.002 0.01 % short circuit current 1 i sc each output clock 25 56 ma pull-up resistor value 1 r pu input pin 680 k w input capacitance 1 c i except x1, x2 8 pf load capacitance 1 c l pins x1, x2 20 pf
4 ics9158-01 electrical characteristics ( continued ) v dd = +5v10%, t a =0c to 70c unless otherwise stated note 1: parameter is guaranteed by design and characterization. not 100% tested in production. ac characteristics parameter symbol test conditions min typ max units output rise time, 0.8 to 2.0v (note 1) t r 30pf load - 1 2 ns rise time, 20% to 80% v dd 1 t r 30pf load - 2.5 3 ns output fall time, 2.0 to 0.8v 1 t f 30pf load - 0.5 1 ns fall time, 80% to 20% v dd 1 t f 30pf load - 1.5 2 ns duty cycle 1 d t 30pf load 40/60 48/52 60/40 % jitter, one sigma 1 t j1s as compared with clock period 0.5 2.0 % jitter, absolute t jab 25% jitter, absolute t jab 16-100 mhz clocks 500 ps input frequency f i 14.318 mhz clock skew between cpu and 2xcpu outputs t sk 100 250 ps frequency transition time 1 t ft from 4 to 50 mhz 13 20 ms
5 ics9158-01 frequency transitions cpu clock decoding table (using 14.318 mhz input. all frequencies in mhz) clock#2 cpu and 2xcpu *5v only peripheral clocks reference clock a key feature of the ics9158-01 is its ability to provide smooth, glitch-free frequency transitions on the cpu and 2xcpu clocks when the frequency select pins are changed. the frequency transition rate does not violate the intel 486 or pentium specification of less than 0.1% frequency change per clock period. using an input clock as a reference the ics9158-01 is designed to accept a 14.318 mhz crystal as the input reference. with some external changes, it is possible to use a crystal oscillator or other clock sources. please see application note aan04 for details on driving the ics9158-01 with a clock. stop clock feature (optional mask version) the ics9158-01 incorporates a unique stop clock feature compatible with static logic processors. when the stop clock pin goes low, the cpuclk will go low after the next occurring falling edge. when stopclk again goes high, cpuclk resumes on the next rising edge of the internal clock. this feature enables fast, glitch-free starts and stops of the cpuclk and is useful in energy start motherboard applications. fs2 (pin 15) fs1 (pin 23) fs0 (pin 24) 2xcpu (pin 21) cpu 0 0 0 0 1 1 1 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 7.580 15.511 59.875 40.090 50.113 66.476 79.772* 100.226* 3.790 7.756 29.938 20.045 25.057 33.238 39.886* 50.113* refclk1 (pin 18) 14.318 busclk (pin 6) fdclk (pin 7) 16.002 24.003
6 ics9158-01 24-dip package ordering information ics9158-01cn24 example: ics xxxx-ppp m package type n=dip ( plastic#) pattern number (2 or 3 digit number for parts with rom code patterns) device type (consists of 3 or 4 digit numbers) prefix ics, av=standard device; gsp=genlock device
7 ics9158-01 ordering information ICS9158-01CM24 example: ics xxxx-ppp m package type m=soic pattern number (2 or 3 digit number for parts with rom code patterns) device type (consists of 3 or 4 digit numbers) prefix ics, av=standard device; gsp=genlock device 24 lead soic lead count 24l dimension l 0.604 ics reserves the right to make changes in the device data identified in this publication without further notice. ics advises its customers to obtain the latest version of all device data to verify that any information being relied upon by the customer is current and accurate.
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