w83194br-b Winbond Electronics Corp America, w83194br-b Datasheet - Page 5

• Manufacturer Part Number: w83194br-b
• Description: Winbond Clock Generator For Intel P4 845 Series Chipset
• Manufacturer: Winbond Electronics Corp America

W83194BR-B/W83194BG-B
CLOCK GEN. FOR INTEL P4 845 SERIES CHIPSET
1. GENERAL DESCRIPTION
The W83194BR-B is a Clock Synthesizer for Intel P4 845 series chipset. W83194BR-B provides all
clocks required for high-speed microprocessor and provides step-less frequency programming and 32
different frequencies of CPU, PCI, and 3V66 clocks setting. All clocks are externally selectable with
smooth transitions.
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The W83194BR-B provides I
C serial bus interface to program the registers to enable or disable each
clock outputs and provides +/-0.25% center type spread spectrum or programmable S.S.T. scale to
reduce EMI.
The W83194BR-B also has watch dog timer and reset output pin to support auto-reset when systems
hanging caused by improper frequency setting.
The W83194BR-B accepts a 14.318 MHz reference crystal as its input and runs on a 3.3V supply.
High drive PCI CLOCK outputs typically provide greater than 1 V /ns slew rate into 30 pF loads. CPU
CLOCK outputs typically provide better than 1 V /ns slew rate into 20 pF loads as maintaining 50± 5%
duty cycle. The fixed frequency outputs as REF and 48 MHz provide better than 0.5V /ns slew rate.
2. PRODUCT FEATURES
• 3 pairs of CPU clock outputs
• 4 3V66 clock outputs
• 9 PCI synchronous clocks
• 2 48MHz clock outputs for USB and DOT
• AGP/PCI clock out supports fix mode with 4 step option
• Slew rate control
• 3V66 leads PCICLK from 1.5ns to 3.5ns
• Smooth frequency switch with selections from 100 to 200MHz
• Step-less frequency programming
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2
• I
C 2-Wire serial interface and I
C read back
• +/- 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
Publication Release Date: October 2006
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Revision 3.1