ICS9248-64 Datasheet, PDF (14/15 Pages) Integrated Circuit Systems – AMD-K7TM System Clock Chip

ICS9248-64
PCI_STOP# Timing Diagram
PCI_STOP# is an asynchronous input to the ICS9248-64. It is used to turn off the PCICLK clocks for low power operation.
PCI_STOP# is synchronized by the ICS9248-64 internally. PCICLK clocks are stopped in a low state and started with a full
high pulse width guaranteed. PCICLK clock on latency cycles are only one rising PCICLK clock off latency is one PCICLK
clock.
CPUCLK
(Internal)
PCICLK
(Internal)
PCICLK
(Free-running)
CPU_STOP#
PCI_STOP#
PWR_DWN#
PCICLK
(External)
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. PD# and CPU_STOP# are shown in a high (true) state.
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