Texas Instruments LMK04828 - Holdover Register Settings; Holdover Functions Configuration

LMK04821 , LMK04826 , LMK04828
www.ti.com SNAS605AR –MARCH 2013–REVISED DECEMBER 2015
9.7.6 (0x14B - 0x152) Holdover
9.7.6.1 LOS_TIMEOUT, LOS_EN, TRACK_EN, HOLDOVER_FORCE, MAN_DAC_EN, MAN_DAC[9:8]
This register contains the holdover functions.
Table 42. Register 0x14B
POR
BIT NAME DESCRIPTION
DEFAULT
This controls the amount of time in which no activity on a CLKin forces a clock switch
event.
Field Value Timeout
0 (0x00) 370 kHz
7:6 LOS_TIMEOUT 0
1 (0x01) 2.1 MHz
2 (0x02) 8.8 MHz
3 (0x03) 22 MHz
Enables the LOS (Loss-of-Signal) timeout control. Valid for MOS clock inputs.
5 LOS_EN 0 0: Disabled
1: Enabled
Enable the DAC to track the PLL1 tuning voltage, optionally for use in holdover mode. After
device reset, tracking starts at DAC code = 512.
4 TRACK_EN 1 Tracking can be used to monitor PLL1 voltage in any mode.
0: Disabled
1: Enabled, will only track when PLL1 is locked.
This bit forces holdover mode. When holdover mode is forced, if MAN_DAC_EN = 1, then
the DAC will set the programmed MAN_DAC value. Otherwise the tracked DAC value will
HOLDOVER
3 0 set the DAC voltage.
_FORCE
0: Disabled
1: Enabled.
This bit enables the manual DAC mode.
2 MAN_DAC_EN 1 0: Automatic
1: Manual
1:0 MAN_DAC[9:8] 2 See MAN_DAC[9:8], MAN_DAC[7:0] for more information on the MAN_DAC settings.
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