w83194br-pt Winbond Electronics Corp America, w83194br-pt Datasheet - Page 4

• Manufacturer Part Number: w83194br-pt
• Description: Stepless Via Pt Main Clock Generator
• Manufacturer: Winbond Electronics Corp America

1. GENERAL DESCRIPTION
The W83194BR-PT is a Clock Synthesizer for VIA PT chipset. W83194BR-PT provides all clocks
required for high-speed microprocessor and provides step-less frequency programming and 32
different frequencies of CPU, PCI, and AGP clocks setting. All clocks are externally selectable with
smooth transitions.
The W83194BR-PT provides I
each clock outputs and provides -0.5% and +/-0.25% center type spread spectrum or programmable
S.S.T. scale to reduce EMI.
The W83194BR-PT also has watchdog timer and reset output pin to support auto-reset when systems
hanging caused by improper frequency setting.
The W83194BR-PT accepts a 14.318 MHz reference crystal as its input and runs on a 3.3V supply.
2. PRODUCT FEATURES
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2 Differential pairs of CPU clock outputs
1 Differential pairs push pull of CPU_CS clock outputs
3 AGP clock outputs
9 PCI synchronous clocks
24_48Mhz clock output for super I/O.
48 MHz clock output for USB.
2 IOAPIC clock outputs.
1 REF clock output.
Skew form CPU to PCI clock 1 to 4 ns, center 2.6 ns
Smooth frequency switch with selections from 100 to 200MHz
Step-less frequency programming
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-0.5% and +/- 0.25% center type spread spectrum
Programmable S.S.T. scale to reduce EMI
Programmable registers to enable/stop each output and select modes
Watch Dog Timer and RESET# output pins
48-pin SSOP package
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C 2-Wire serial interface and support byte read/write and block read/write.
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C serial bus interface to program the registers to enable or disable
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Publication Release Date: April 13, 2005
W83194BR-PT
Revision 1.1