
2
ICS94236
0451A
—
01/10/03
General Description
The
ICS94236
is a main clock synthesizer chip for AMD-K7 based systems with VIA style chipset. This provides all
clocks required for such a system.
The
ICS94236
belongs to ICS new generation of programmable system clock generators. It employs serial
programming I
2
C interface as a vehicle for changing output functions, changing output frequency, configuring output
strength, configuring output to output skew, changing spread spectrum amount, changing group divider ratio and dis/
enabling individual clocks. This device also has ICS propriety 'Watchdog Timer' technology which will reset the
frequency to a safe setting if the system become unstable from over clocking.
Pin Descriptions
Notes:
1:
2:
Internal Pull-up Resistor of 120K to 3.3V on indicated inputs
Bidirectional input/output pins, input logic levels are latched at internal power-on-reset. Use
10Kohm resistor to program logic Hi to VDD or GND for logic low.
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