9DB833 Datasheet, PDF (12/18 Pages) Integrated Circuit Systems – SMBus Interface; unused outputs can be disabled

9DB833
EIGHT OUTPUT DIFFERENTIAL BUFFER FOR PCIE GEN1,2,3
SMBus Table: Frequency Select Register, READ/WRITE ADDRESS (Selectable)
Byte 0 Pin # Name
Control Function
Type
Bit 7
-
PD_Mode
PD# drive mode
RW
Bit 6
-
OE_Mode
OE#_Stop drive mode
RW
Bit 5
-
Reserved
Bit 4
-
Reserved
Bit 3
-
MODE1
BYPASS#/PLL1
RW
Bit 2
-
Reserved
Bit 1
-
MODE0
BYPASS#/PLL0
RW
0
1
driven
Hi-Z
driven
Hi-Z
SeeOperating Mode
Readback Table
SeeOperating Mode
Readback Table
Default
1
1
0
X
Latched
1
Latched
Bit 0
-
SRC_DIV#
SRC Divide by 2 Select
RW
x/2
x/1
1
SMBus Table: Output Control Register
Byte 1 Pin # Name
Control Function
Type
0
Bit 7 42,41
DIF_7
Output Enable
RW Disable
Bit 6 38,37
DIF_6
Output Enable
RW Disable
Bit 5 34,33
DIF_5
Output Enable
RW Disable
Bit 4 30,29
DIF_4
Output Enable
RW Disable
Bit 3 20,21
DIF_3
Output Enable
RW Disable
Bit 2 16,17
DIF_2
Output Enable
RW Disable
Bit 1 12,13
DIF_1
Output Enable
RW Disable
Bit 0
8,9
DIF_0
Output Enable
RW Disable
NOTE: The SMBus Output Enable Bit must be '1' AND the respective OE pin must be active for the output to run.
1
Enable
Enable
Enable
Enable
Enable
Enable
Enable
Enable
Default
1
1
1
1
1
1
1
1
SMBus Table: OE Pin Control Register
Byte 2 Pin #
Bit 7 42,41
Bit 6 38,37
Bit 5 34,33
Bit 4 30,29
Bit 3 20,21
Bit 2 16,17
Bit 1 12,13
Bit 0
8,9
Name
DIF_7
DIF_6
DIF_5
DIF_4
DIF_3
DIF_2
DIF_1
DIF_0
Control Function
DIF_7 Stoppable with OE7#
DIF_6 Stoppable with OE6#
DIF_5 Stoppable with OE5#
DIF_4 Stoppable with OE4#
DIF_3 Stoppable with OE3#
DIF_2 Stoppable with OE2#
DIF_1 Stoppable with OE1#
DIF_0 Stoppable with OE0#
NOTE: If you wish the default to be "Stoppable" see the 9DB834.
Type
RW
RW
RW
RW
RW
RW
RW
RW
0
Free-run
Free-run
Free-run
Free-run
Free-run
Free-run
Free-run
Free-run
1
Stoppable
Stoppable
Stoppable
Stoppable
Stoppable
Stoppable
Stoppable
Stoppable
Default
0
0
0
0
0
0
0
0
SMBus Table: Reserved Register
Byte 3 Pin # Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Control Function
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Type
0
1
Default
X
X
X
X
X
X
X
X
IDT® EIGHT OUTPUT DIFFERENTIAL BUFFER FOR PCIE GEN1,2,3
12
9DB833
REV G 082515