BWx_PLLA, FAST_BWx_PLLA, and BWx_HO_PLLA parameters to take effect. Note that individual SOFT_RST_PLLA (0x001C[1])
does not update the bandwidth parameters.
Table 15.136. 0x0415-0x041B MA Divider Numerator for DSPLL A
Reg Address
Bit Field
Type
Setting Name
Description
0x0415
7:0
R/W
M_NUM_PLLA
56-bit number.
0x0416
15:8
R/W
M_NUM_PLLA
0x0417
23:16
R/W
M_NUM_PLLA
0x0418
31:24
R/W
M_NUM_PLLA
0x0419
39:32
R/W
M_NUM_PLLA
0x041A
47:40
R/W
M_NUM_PLLA
0x041B
55:48
R/W
M_NUM_PLLA
The MA divider numerator values are calculated by ClockBuilder Pro for a particular frequency plan and are written into these registers.
Table 15.137. 0x041C-0x041F MA Divider Denominator for DSPLL A
Reg Address
Bit Field
Type
Setting Name
Description
0x041C
7:0
R/W
M_DEN_PLLA
32-bit number.
0x041D
15:8
R/W
M_DEN_PLLA
0x041E
23:16
R/W
M_DEN_PLLA
0x041F
31:24
R/W
M_DEN_PLLA
The loop MA divider denominator values are calculated by ClockBuilder Pro for a particular frequency plan and are written into these
registers.
Table 15.138. 0x0420 M Divider Update Bit for PLL A
Reg Address
Bit Field
Type
Setting Name
Description
0x0420
0
S
M_UPDATE_PLLA Must write a 1 to this bit to cause PLL A M divider
changes to take effect.
Bits 7:1 of this register have no function and can be written to any value.
Table 15.139. 0x0421 DSPLL A M Divider Fractional Enable
Reg Address
Bit Field
Type
Setting Name
Description
0x0421
3:0
R/W
M_FRAC_MODE_P
LLA
M feedback divider fractional mode.
Must be set to 0xB for proper operation
0x0421
4
R/W
M_FRAC_EN_PLLA M feedback divider fractional enable.
0: Integer-only division
1: Fractional (or integer) division - Required for DCO
operation.
0x0421
5
R/W
Reserved
Must be set to 1 for DSPLL A
Si5397/96 Reference Manual
Si5397A/B Register Map
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