Integrated
Circuit
Systems, Inc.
General Description Features
ICS9169C-41
Block Diagram
Frequency Generator for PentiumPro™ Based Systems
9169-41Rev D 5/02/00
Pin Configuration
34-Pin SSOP
Pentium is a trademark on Intel Corporation.
• 12 selectable CPU/SDRAM/AGP clocks up to 75 MHz
• Six PCI clocks, synchronous or asynchronous mode, pin
selectable by Bus Select input (pin 19)
• One USB clock at 48MHz, meets Intel jitter, accuracy, as
well as rise and fall time requirements
• One I/O clock at 24MHz
• Two Ref. Clocks at 14.318MHz
• CPU clocks to PCI clock skew of 1-4ns (CPU early)
• Low CPU and PCI clock jitter <200ps
• Low skew outputs, skew window 250ps for CPU clocks
and for PCI clocks
• Improved output drivers are designed for low EMI
• Test Mode
• 3.3V ±10% operation
• Space saving and low cost 34-pin SSOP package
The ICS9169C-41 is a Clock Synthesize/Driver chip for
Pentium, PentiumPro or Cyrix 68x86 based motherboards
using SDRAM.
Features include four dual purpose I/O pins which provide
extra CPU clocks and enable the part to be packaged in a
low-cost 34-pin SSOP package. These four pins latch the
select inputs at the internal Power-On Reset. Additionally,
the device meets the Pentium and PentiumPro power-up
stabilization, which requires that CPU and PCI clocks be
stable within 2ms after power-up.
The ICS9169C-41 clock outputs are designed for low EMI
emissions. Controlled rise and fall times, unique output
driver circuits and innovative circuit layout techniques enable
the ICS9169C-41 to have lower EMI than other clock
devices.
The ICS9169C-41 accepts a 14.318MHz reference crystal or
clock as its input and runs from a 3.3V supply.
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.