SI5374 Datasheet, PDF (25/69 Pages) Silicon Laboratories – 4-PLL ANY-FREQUENCY PRECISION CLOCK MULTIPLIER/JITTER ATTENUATOR

Si5374
Register 3.
Bit
D7
D6
D5
D4
D3
D2
D1
D0
Name CKSEL_REG[1:0]
DHOLD SQ_ICAL
Type
R/W
R/W
R/W
R
R
R
R
Reset value = 0000 0101
Bit
Name
Function
7:6 CKSEL_REG [1:0] CKSEL_REG.
If the device is operating in register-based manual clock selection mode
(AUTOSEL_REG = 00), and CKSEL_PIN = 0, then these bits select which input
clock will be the active input clock. If CKSEL_PIN = 1 and AUTOSEL_REG = 00, the
CS_CA input pin continues to control clock selection and CKSEL_REG is of no con-
sequence.
00: CKIN_1 selected.
01: CKIN_2 selected.
10: Reserved
11: Reserved
5
DHOLD
DHOLD.
Forces the device into digital hold. This bit overrides all other manual and automatic
clock selection controls.
0: Normal operation.
1: Force digital hold mode. Overrides all other settings and ignores the quality of the
input clocks.
4
SQ_ICAL
SQ_ICAL.
This bit determines if the output clocks will remain enabled or be squelched (dis-
abled) during an internal calibration. See Table 9 on page 56.
0: Output clocks enabled during ICAL.
1: Output clocks disabled during ICAL.
3:0
Reserved
Rev. 1.1
25