ICS9250-38 Datasheet, PDF (15/18 Pages) Integrated Circuit Systems – Frequency Generator with 200MHz Differential CPU Clocks

ICS9250-38
PCI_STOP# - Assertion (transition from logic "1" to logic "0")
The impact of asserting the PCI_STOP# signal will be the following. All PCI[6:0] and stoppable PCI_F[2,0] clocks will
latch low in their next high to low transition. The PCI_STOP# setup time tsu is 10 ns, for transitions to be recognized
by the next rising edge.
Assertion of PCI_STOP# Waveforms
PCI_STOP#
PCI_F[2:0] 33MHz
PCI[6:0] 33MHz
tsu
CPU_STOP# - Assertion (transition from logic "1" to logic "0")
The impact of asserting the CPU_STOP# pin is all CPU outputs that are set in the I²C configuration to be stoppable
via assertion of CPU_STOP# are to be stopped after their next transition following the two CPU clock edge sampling
as shown. The final state of the stopped CPU signals is CPUT=High and CPUC=Low. There is to be no change to the
output drive current values. The CPUT will be driven high with a current value equal to (MULTSEL0) X (I REF), the CPUC
signal will not be driven.
Assertion of CPU_STOP# Waveforms
CPU_STOP#
CPUT
CPUC
CPU_STOP# Functionality
CPU_STOP#
1
0
CPUT
Normal
iref * Mult
CPUC
Normal
Float
0404B—12/23/02
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