
IDTTM/ICSTM Four Output Differential Buffer for PCIe Gen 2 with Spread
1626
09/17/09
ICS9DS400
Four Output Differential Buffer for PCIe for Gen 2 with Spread
12
Advance Information
SMBus Table: Frequency Select Register, READ/WRITE ADDRESS (D8/D9)
Pin #
Name
Control Function
Type
0
1
Default
Bit 7
PD_Mode
PD# drive mode
RW
driven
Hi-Z
0
Bit 6
STOP_Mode
SRC_Stop# drive mode
RW
driven
Hi-Z
0
Bit 5
0
Bit 4
SPREAD_AMT(1)
Spread % MSB
RW
Latch
Bit 3
SPREAD_AMT(0)
Spread % LSB
RW
1
Bit 2
SPREAD_EN
Turns on spread
RW
SS Off
SS On
Latch
Bit 1
BYPASS#
BYPASS#_SSCG
RW
fan-out
SSCG
Latch
Bit 0
Byte0 CONTROL
Selects control source of Byte 0
RW
Smbus
Input Pins
1
SMBus Table: Output Control Register
Pin #
Name
Control Function
Type
0
1
Default
Bit 7
Reserved
RW
1
Bit 6
DIF_6
Output Enable
RW
Disable
Enable
1
Bit 5
DIF_5
Output Enable
RW
Disable
Enable
1
Bit 4
Reserved
RW
1
Bit 3
Reserved
RW
1
Bit 2
DIF_2
Output Enable
RW
Disable
Enable
1
Bit 1
DIF_1
Output Enable
RW
Disable
Enable
1
Bit 0
Reserved
RW
1
NOTE: The SMBus Output Enable Bit must be '1' AND the respective OE pin must be active for the output to run!
SMBus Table: OE Pin Control Register
Pin #
Name
Control Function
Type
0
1
Default
Bit 7
Reserved
RW
0
Bit 6
DIF_6
DIF_6 Stoppable with OE6
RW
Free-run
Stoppable
0
Bit 5
Reserved
RW
0
Bit 4
Reserved
RW
0
Bit 3
Reserved
RW
0
Bit 2
Reserved
RW
0
Bit 1
DIF_1
DIF_1 Stoppable with OE1
RW
Free-run
Stoppable
0
Bit 0
Reserved
RW
0
SMBus Table: Reserved Register
Pin #
Name
Control Function
Type
0
1
Default
Bit 7
X
Bit 6
X
Bit 5
X
Bit 4
X
Bit 3
X
Bit 2
X
Bit 1
X
Bit 0
X
Reserved
-
Reserved
6,7
-
Byte 3
-
9,10
-
Byte 2
-
6,7
22,23
19,20
Byte 1
-
Reserved
Byte 0
-
Reserved
1
00 = -0.125%
01 = -0.25%
10 = -0.375%
11 = -0.50%
-
28
22
-
Notes: Pins 1, 22 and 28 are latched into Byte 0 on the first power up of the device. Bits [4:1] will NOT reflect
changes in these pin states after power up, even though the pins are controlling the function of the part. Setting
Byte 0 bit 0 to 0 allows the SMBus to write Bits [4:1] and transfers control of the functions from the pins to SMBus.
Once Byte 0 bit 0 is set to 0, the pins no longer impact Byte 0, bits [4:1] or the device function.