GENERAL DESCRIPTION The W83194R-67B is a Clock Synthesizer which provides all clocks required for high-speed RISC or CISC microprocessor such as Intel Pentium , AMD and Cyrix. W83194R-67B provides sixteen CPU/PCI frequencies which are externally selectable with smooth transitions. W83194R-67B also provides 13 SDRAM clocks controlled by the none-delay buffer_in pin. PRODUCT FEATURES • Supports PentiumÔ , AMD, Cyrix CPU with I2C. • 4 CPU clocks (one free-running CPU clock) • 13 SDRAM clocks for 3 DIMs • 6 PCI synchronous clocks • Optional single or mixed supply: (Vddq1=Vddq2 = Vddq3 = Vddq4 = VddL1 =VddL2= 3.3V) or (Vddq1= Vddq2 = Vddq3=Vddq4 = 3.3V, VddL1 = VdqL2 = 2.5V) • < 250ps skew among CPU and SDRAM clocks • < 4ns 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 60 MHz to 124 MHz CPU • I2C 2-Wire serial interface and I2C read back • 0~0.5% down type or ±0.25% or ±0.5% spread spectrum function to reduce EMI • Programmable registers to enable/stop each output and select modes (mode as Tri-state or Normal ) • 2ms power up clock stable time • MODE pin for power Management • One 48 MHz for USB & one 24 MHz for super I/O • Packaged in 48-pin SSOP
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