Integrated
Circuit
Systems, Inc.
AV9172
Low Skew Output Buffer
General Description
The
AV9172
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 鹵500ps, the
part acts as a 鈥渮ero delay鈥?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擄 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.
Features
AV9172-07
input is 66 MHz with 66 and 33 MHz
output buffers
鈥?AV9172-01
is pin compatible with Gazelle GA1210E
鈥?鹵250ps skew (max) between outputs
鈥?鹵500ps skew (max) between input and outputs
鈥?Input frequency range from 10 MHz to 50 MHz
(-01, -03) and from 20 MHz to 100 MHz (-07)
鈥?Output frequency range from 10 MHz to 100 MHz
(-01, -03, -07)
鈥?Special mode for two-phase clock generation
鈥?Inputs and outputs are fully TTL-compatible
鈥?CMOS process results in low power supply current
鈥?High drive, 25mA outputs
鈥?Low cost
鈥?16-pin SOIC (150-mil) or 16-pin PDIP package
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
AV9172-01
AV9172-03
AV9172-07
DESCRIPTION
Second source of GA1210E
Clock doubler and buffer
Clock buffer for 66 MHz input
鈥?/div>
Block Diagram
AV9172RevB060297P
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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