W83194AR-96 Datasheet | Winbond

DESCRIPTION The W83194AR-96 is a Clock Synthesizer for Intel Whitney chipset. W83194AR-96 provides all clocks required for high-speed RISC or CISC microprocessor and also provides 32 different frequencies of CPU, SDRAM, PCI, 3V66, IOAPIC clocks frequency setting. All clocks are externally selectable with smooth transitions. The W83194AR-96 provides I C serial bus interface to program the registers to enable or disable each clock outputs and provides 0.25% center and 0-0.5% down type spread spectrum to reduce EMI. The W83194AR-96 accepts a 14.318 MHz reference crystal as its input and runs on a 3.3V supply. High drive PCI and SDRAM CLOCK outputs typically provide greater than 1 V /ns slew rate into 30 p F loads. CPU CLOCK outputs typically provide better than 1 V /ns slew rate into 20 p F loads as maintaining 50± 5% duty cycle. The fixed frequency outputs as REF, 24MHz, and 48 MHz provide better than 0.5V /ns slew rate. 1.0 PRODUCT FEATURES - - - - - - - - - - - - 2 CPU clocks 9 SDRAM clocks for 2 DIMMs 8 PCI synchronous clocks. Optional single or mixed supply: (VDDR = VDDP=VDDS = VDD48 = VDD3 = 3.3V, VDDA=VDDC=2.5V) Skew form CPU to PCI clock -1 to 4 ns, center 2.6 ns Smooth frequency switch with selections from 66.8 to 200MHz 2 2 I C 2-Wire serial interface and I C read back 0.25% or 0.5% center type spread spectrum Programmable registers to enable/stop each output and select modes (mode as Tri-state or Normal ) 48 MHz for USB 24 MHz for super I/O Packaged in 48-pin SSOP -1- Publication Release Date: July 1999 Revision 0.35 PRELIMINARY 3.0 PIN CONFIGURATION REF1/- APIC_SEL VDDR Xin Xout VSS VSS 3V66-0 3V66-1 VDD3 VDDP PCICLK0/ FS0# PCICLK1/ FS1# PCICLK2/- SEL24_48# VSS PCICLK3/ FS4# PCICLK4 PCICLK5 VDDP PCICLK6 PCICLK7 VSS PD# - SDCLK - SDATA 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32 31 30 29 28 27 26 25 Vdd A IOAPIC VDDC CPUCLK0 CPUCLK1 VSS VSS SDRAM 0 SDRAM 1 SDRAM 2 VDDS SDRAM 3...