ICS9FG1201H
Frequency Gearing Clock for CPU, PCIe Gen1, Gen2, & FBD
Pin Description (continued)
Pin # Pin Name
Type
Pin Description
29
SMBCLK
IN
Clock pin of SMBUS circuitry, 5V tolerant
SMBus address bit 2. When Low, the part operates as a fanout buffer
with the PLL bypassed. When High, the part operates as a zero-delay
buffer (ZDB) with the PLL operating.
30
SMB_A2_PLLBYP#
IN
0 = fanout mode (PLL bypassed), 1 = ZDB mode (PLL used)
Active low input for enabling DIF pair 6.
1 = tri-state outputs, 0 = enable outputs
0.7V differential complement clock output
0.7V differential true clock output
31
OE6#
IN
32
33
DIF_6#
DIF_6
OUT
OUT
Active low input for enabling DIF pair 7.
1 = tri-state outputs, 0 = enable outputs
0.7V differential complement clock output
0.7V differential true clock output
34
OE7#
IN
35
36
37
38
39
40
DIF_7#
DIF_7
GND
OUT
OUT
PWR
PWR
OUT
OUT
Ground pin.
VDD
Power supply, nominal 3.3V
DIF_8#
DIF_8
0.7V differential complement clock output
0.7V differential true clock output
Active low input for enabling DIF pair 8.
1 = tri-state outputs, 0 = enable outputs
0.7V differential complement clock output
0.7V differential true clock output
41
OE8#
IN
42
43
DIF_9#
DIF_9
OUT
OUT
Active low input for enabling DIF pair 9.
1 = tri-state outputs, 0 = enable outputs
Vtt_PwrGd# is an active low input used to determine when latched
inputs are ready to be sampled. PD is an asynchronous active high
input pin used to put the device into a low power state. The internal
clocks, PLLs and the crystal oscillator are stopped.
3.3V tolerant low threshold input for CPU frequency selection. This
pin requires CK410 FSA. Refer to input electrical characteristics for
Vil_FS and Vih_FS threshold values.
44
OE9#
IN
45
VTT_PWRGD#/PD
IN
46
FS_A_410
IN
47
48
49
50
51
52
DIF_10#
DIF_10
GND
OUT
OUT
PWR
PWR
OUT
OUT
0.7V differential complement clock output
0.7V differential true clock output
Ground pin.
VDD
Power supply, nominal 3.3V
DIF_11#
DIF_11
0.7V differential complement clock output
0.7V differential true clock output
Active low input for enabling output pairs 10 and 11.
1 = tri-state outputs, 0 = enable outputs
This pin establishes the reference current for the differential current-
mode output pairs. This pin requires a fixed precision resistor tied to
ground in order to establish the appropriate current. 475 ohms is the
standard value.
53
OE10_11#
IN
54
IREF
OUT
55
56
GNDA
VDDA
PWR
PWR
Ground pin for the PLL core.
3.3V power for the PLL core.
IDTTM/ICSTM Frequency Gearing Clock for CPU, PCIe Gen1, Gen2, & FBD
1371F — 09/23/09
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