Si5345-44-42-D-RM
160
Rev. 1.0
Si5344
14.4.5. Page 4 Registers Si5344
This register is used for enabling the zero delay mode (ZDM) and selecting the source. The phase difference
between the output, which is connected to the selected input below will be nulled to zero. When in zero delay
mode, the DSPLL cannot have either hitless or automatic switching. In addition, the frequency of the clock selected
by ZDM_IN_SEL must either be the same or have a simple integer relationship to the clock at the FB_IN pins. Pin
controlled clock selection is available in ZD mode (see register 0x052A).
Register 0x0487 Zero Delay Mode Setup
Reg Address
Bit Field
Type
Name
Description
0x0487
0
R/W
ZDM_EN
0 to disable ZD mode
1 to enable ZD mode
0x0487
2:1
R/W
ZDM_IN_SEL
Clock input select when in ZD mode.
0 for IN0, 1 for IN1,2 for IN2,
3 reserved
Note: In ZD mode the feedback clock
comes into IN3
0x0487
4
R/W
ZDM_AUTOSW_EN