AV9154A-27CS16

Integrated Circuit Systems, Inc. AV9154A Low-Cost 16-Pin Frequency Generator General Description . The AV9154A is a 0.8mm version of the industry leading AV9154. Like the AV9154, the AV9154A is a low-cost frequency generator designed for general purpose PC and disk drive applications. However, because the AV9154A uses 0.8mm technology and the latest phaselocked loop architecture, it offers performance advantages that enable the device to be sold into Pentium™ systems. The AV9154A guarantees a 45/55 duty cycle over all frequencies. In addition, a worst case jitter of ±250ps is specified at Pentium frequencies. 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 when slowing the CPU speed. The AV9154A makes a gradual transition between frequencies so that it obeys the Intel cycle-to-cycle timing specifications for 486 and Pentium systems. The AV9154A-42 and AV9154A-43 devices offer features specifically for green PCs. The AV9154A-42 and -43 have a single pin that, when pulled low, will smoothly slow the 2XCPU clock to 8 MHz. This is ideal for dynamic DX microprocessors. The AV9154A-43 not only has the slow clock feature, but also offers a glitch-free stop clock for static SX microprocessors. The STOPCLK# pin, when pulled low, enables the 2XCPU clock to go low only after completing its last full cycle. The clock continues to run internally, and will be output again on the first full cycl...