Si5345-44-42-D-RM
44
Rev. 1.0
6.4.1. Output Driver State When Disabled
The disabled state of an output driver is configurable as disable low or disable high.
6.4.2. Synchronous Output Disable Feature
The output drivers provide a selectable synchronous disable feature. Output drivers with this feature turned on will
wait until a clock period has completed before the driver is disabled. This prevents unwanted runt pulses from
occurring when disabling an output. When this feature is turned off, the output clock will disable immediately
without waiting for the period to complete. The default state is for the synchronous output to be disabled.
Table 28. Output Driver State Control Registers
Register Name
Hex Address [Bit Field]
Function
Si5345
Si5344
Si5342
OUT0_DIS_STATE
0x0109[5:4]
0x0113[5:4]
0x0113[5:4]
Determines the state of
an output driver when
disabled.
Selectable as:
Disable logic low
Disable logic high
OUT1_ DIS_STATE
0x010E[5:4]
0x0118[5:4]
0x0118[5:4]
OUT2_ DIS_STATE
0x0113[5:4]
0x0127[5:4]
—
OUT3_ DIS_STATE
0x0118[5:4]
0x012C[5:4]
—
OUT4_ DIS_STATE
0x011D[5:4]
—
—
OUT5_ DIS_STATE
0x0122[5:4]
—
—
OUT6_ DIS_STATE
0x0127[5:4]
—
—
OUT7_ DIS_STATE
0x012C[5:4]
—
—
OUT8_ DIS_STATE
0x0131[5:4]
—
—
OUT9_ DIS_STATE
0x013B[5:4]
—
—
Table 29. Synchronous Disable Control Registers
Register Name
Hex Address [Bit Field]
Function
Si5345
Si5344
Si5342
OUT0_SYNC_EN
0x0109[3]
0x0113[3]
0x0113[3]
Synchronous output dis-
able. When this feature
is enabled, the output
clock will always finish a
complete period before
disabling. When this fea-
ture is disabled, the out-
put clock will disable
immediately without
waiting for the period to
complete.
This feature is disabled
by default.
OUT1_ SYNC_EN
0x010E[3]
0x0118[3]
0x0118[3]
OUT2_ SYNC_EN
0x0113[3]
0x0127[3]
—
OUT3_ SYNC_EN
0x0118[3]
0x012C[3]
—
OUT4_ SYNC_EN
0x011D[3]
—
—
OUT5_ SYNC_EN
0x0122[3]
—
—
OUT6_ SYNC_EN
0x0127[3]
—
—
OUT7_ SYNC_EN
0x012C[3]
—
—
OUT8_ SYNC_EN
0x0131[3]
—
—
OUT9_ SYNC_EN
0x013B[3]
—
—