SI5338 Datasheet, PDF (57/170 Pages) Silicon Laboratories – I2C-PROGRAMMABLE ANY-FREQUENCY, ANY-OUTPUT QUAD CLOCK GENERATOR

Si5338
Register 29.
Bit
Name
Type
D7
D6
D5
PFD_IN_REF[2:0]
R/W
D4
D3
P1DIV_IN[4:3]
R/W
D2
D1
D0
P1DIV[2:0]
R/W
Reset value = xxxx xxxx
Bit
Name
Function
Selects the input clock to be provided to the reference input of PLL Phase
Frequency Detector (PFD).
0: P1DIV_IN selected
1: P2DIV_IN selected
7:5
PFD_IN_REF[2:0]
2: P1DIV_OUT (P1 divider output) selected
3: P2DIV_OUT (P2 divider output) selected
4: XOCLK selected
5: No Clock selected
6: Reserved
7: Reserved
These two bits along with reg28[4:2] create a 5-bit field that selects the input to
the P1 divider [reg29[4:3] reg28[4:2]] = P1DIV_IN[4:0].
4:3
P1DIV_IN[4:3]
00000b: Clock from IN,2 selected
01010b: Clock from IN3 selected
10101b: Crystal oscillator selected
All other bit values are reserved
Sets the value of the P1 divider.
0: Divide by 1
1: Divide by 2
2:0
P1DIV[2:0]
2: Divide by 4
3: Divide by 8
4: Divide by 16
5: Divide by 32
Rev. 0.6
57