ICS9248-185 Datasheet, PDF (8/11 Pages) Integrated Circuit Systems – Frequency Generator & Integrated Buffers for PENTIUM/ProTM & K6

ICS9248 - 185
PCI_STOP# Timing Diagram
PCI_STOP# is an asynchronous input to the ICS9248-185. It is used to turn off the PCICLK clocks for low power operation.
PCI_STOP# is synchronized by the ICS9248-185 internally. The minimum that the PCICLK clocks are enabled (PCI_STOP#
high pulse) is at least 10 PCICLK clocks. PCICLK clocks are stopped in a low state and started with a full high pulse width
guaranteed. PCICLK clock on latency cycles are only three rising PCICLK clocks, off latency is one PCICLK clock.
CPUCLK
(Internal)
PCICLK_F
(Internal)
PCICLK_F
(Free-running)
CLK_STOP#
PCI_STOP#
PCICLK [6:0]
Notes:
1. All timing is referenced to the Internal CPUCLK (defined as inside the ICS9248 device.)
2. PCI_STOP# is an asynchronous input, and metastable conditions may exist. This signal is required to be synchronized
inside the ICS9248.
3. All other clocks continue to run undisturbed.
4. CLK_STOP# is shown in a high (true) state.
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