20
Integrated
Circuit
Systems, Inc.
ICS932S401
0921G—08/24/09
The time from the de-assertion of PD or until power supply ramps to get stable clocks will be less than 1.8ms. If the drive
mode control bit for PD tristate is programmed to '1' the stopped differential pair must first be driven high to a minimum of
200mV in less than 300µs of PD deassertion.
PD De-assertion
PWRDWN#
Tstable
<1.8mS
Tdrive_PwrDwn#
<300µS, >200mV
CPU, 133MHz
CPU#, 133MHz
SRC, 100MHz
SRC# 100MHz
USB, 48MHz
PCI, 33MHz
REF, 14.31818
Test Clarification Table
Comments
FS_C/TEST
_SEL
HW PIN
FS_B/TEST
_MODE
HW PIN
TEST
ENTRY
BIT
B6b6
REF/N or
HI-Z
B6b7 OUTPUT
0 X 0 X NORMAL
10X0HI-Z
10X1REF/N
11X0REF/N
11X1REF/N
0X10HI-Z
0X11REF/N
B6b6: 1= ENTER TEST MODE, Default = 0 (NORMAL OPERATION)
B6b7: 1= REF/N, Default = 0 (HI-Z)
HW SW
Power-up w/ TEST_SEL = 1 to enter test mode
Cycle power to disable test mode
FS_C./TEST_SEL -->3-level latched input
If power-up w/ V>2.0V (-0.3V) then use TEST_SEL
If power-up w/ V<2.0V (-0.3V) then use FS_C
FS_B/TEST_MODE -->low Vth input
TEST_MODE is a
If TEST_SEL HW pin is 0 during power-up,
test mode can be invoked through B6b6.
If test mode is invoked by B6b6, only B6b7
is used to select HI-Z or REF/N
FS_B/TEST_Mode pin is not used.
Cycle power to disable test mode, one shot control