W83194BR-39B中文資料華邦電子數(shù)據(jù)手冊(cè)PDF規(guī)格書

GENERAL DESCRIPTION

The W83194BR-39B is a Clock Synthesizer which provides all clocks required for high-speed RISC or CISC microprocessor such as Intel Pentium II or Pentium III. W83194BR-39B provides 64 CPU/PCI frequencies which are selectable with smooth transitions by hardware or software. W83194BR-39B also provides 13 SDRAM clocks controlled by the none-delay buffer_in pin.

PRODUCT FEATURES

? Supports Pentium? II and !!! CPU with I2C.

? 2 CPU clocks (one free-running CPU clock)

? 13 SDRAM clocks for 3 DIMMs

? 6 PCI synchronous clocks

? One IOAPIC clock for multiprocessor support

? Optional single or mixed supply:

(Vddq1=Vddq2 = Vddq3 = Vddq4 = VddL1 =VddL2= 3.3V) or (Vddq1= Vddq2 = Vddq3=Vddq4 = 3.3V, VddL1 = VddL2 = 2.5V)

? < 250ps skew among CPU and SDRAM clocks

? < 250ps skew among PCI clocks

? < 5ns propagation delay SDRAM from buffer input

? Skew from CPU (earlier) to PCI clock 1 to 4ns, center 2.6ns.

? Smooth frequency switch with selections from 66 MHz to 200 MHz CPU

? Step-less frequency programming by controlling the VCO freq. and the clock output divisor ratio

? I2C 2-Wire serial interface and I2C read back

? ±0.25 or ±0.5 spread spectrum function to reduce EMI in freq. table mode

? Programmable spread spectrum in the M/N step-less mode

? Programmable registers to enable/stop each output and select modes

? MODE pin for power Management

? RESET# out when watch dog timer time out

? One 48 MHz for USB & one 24 MHz for super I/O

? 48-pin SSOP package