Integrated
Circuit
Systems, Inc.
General Description Features
AV 91 7 2
Block Diagram
AV9172RevB060297P
The A V9172 is designed to generate low skew clocks for
clock distribution in high-performance PCs and workstations.
It uses phase-locked loop technology to align the phase and
frequency of the output clocks with an input reference clock.
Because the input to output skew is guaranteed to ± 500ps, the
part acts as a “zero delay” buffer.
The AV9172 has six configurable outputs. The AV9172-01
version has one output that runs at the same phase and
frequency as the reference clock. A second output runs at the
same frequency as the reference, but can either be in phase or
180° out of phase from the input clock. Two outputs are
provided that are at twice the reference frequency and in
phase with the reference clock. The final outputs can be
programmed to be replicas of the 2x clocks or non-overlapping
two phase clocks at twice the reference frequency. The
AV9172-01 and AV9172-03 operates with input clocks
from 10 MHz to 50 MHz while producing outputs from
10 MHz to 100 MHz. The AV9172-07 operates with input
clocks from 20 to 100 MHz.
The use of a phase-locked loop (PLL) allows the output
clocks to run at multiples of the input clock. This permits
routing of a lower speed clock and local generation of a
required high speed clock. Synchronization of the phase
relationship between the input clock and the output clocks is
accomplished when one output clock is connected to the
input pin FBIN. The PLL circuitry matches rising edges of the
input clock and output clocks.
• AV9172-07 input is 66 MHz with 66 and 33 MHz
output buffers
• AV9172-01 is pin compatible with Gazelle GA1210E
• ±250ps skew (max) between outputs
• ±500ps skew (max) between input and outputs
• Input frequency range from 10 MHz to 50 MHz
(-01, -03) and from 20 MHz to 100 MHz (-07)
• Output frequency range from 10 MHz to 100 MHz
(-01, -03, -07)
• Special mode for two-phase clock generation
• Inputs and outputs are fully TTL-compatible
• CMOS process results in low power supply current
• High drive, 25mA outputs
• Low cost
• 16-pin SOIC (150-mil) or 16-pin PDIP package
Low Skew Output Buffer
The AV9172 is fabricated using CMOS technology which
results in much lower power consumption and cost compared
with the gallium arsenide-based GA1210E. The typical
operating current for the AV9172 is 50mA versus 120mA for
the GA1210E.
ICS offers several versions of the AV9172. The different
devices are shown below:
PART DESCRIPTION
AV9172-01 Second source of GA1210E
AV9172-03 Clock doubler and buffer
AV9172-07 Clock buffer for 66 MHz input
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.