器件名称: W158
功能描述: Spread Spectrum System Frequency Synthesizer
文件大小: 166.07KB 共12页
简 介:W158
Spread Spectrum System Frequency Synthesizer
Features
Maximized EMI suppression using Cypress’s spread spectrum technology Intel CK98 Specification compliant 0.5% downspread outputs deliver up to 10 dB lower EMI Four skew-controlled copies of CPU output Eight copies of PCI output (synchronous w/CPU output) Four copies of 66-MHz fixed frequency 3.3V clock Two copies of CPU/2 outputs for synchronous memory reference Three copies of 16.67-MHz IOAPIC clock, synchronous to CPU clock One copy of 48-MHz USB output Two copies of 14.31818-MHz reference clock Programmable to 133- or 100-MHz operation Power management control pins for clock stop and shut down Available in 56-pin SSOP CPU Output Jitter: ...................................................... 150 ps CPUdiv2, IOAPIC Output Jitter: ..................................250 ps 48 MHz, 3V66, PCI Output Jitter: ................................ 500 ps CPU0:3, CPUdiv2_ 0:1 Output Skew: ......................... 175 ps PCI_F, PCI1:7 Output Skew: .......................................500 ps 3V66_0:3, IOAPIC0:2 Output Skew: ...........................250 ps CPU to 3V66 Output Offset: ........... 0.0 to1.5 ns (CPU leads) 3V66 to PCI Output Offset:.......... 1.5 to 3.0 ns (3V66 leads) CPU to IOAPIC Output Offset: ...... 1.5 to 4.0 ns (CPU leads) CPU to PCI Output Offset: ............ 1.5 to 4.0 ns (CPU leads) Logic inputs, except SEL133/100#, have 250-k pull-up resistors Table 1. Pin Selectable Frequency[1] SEL133/100#……
