
iiiPeriPheraLModuLes1(systeM):CLoCkManageMentunit(CMu)
iii-1-12
ePson
s1C33L17teChniCaLManuaL
iii.1.6.4otherPLLsettings
V-divider
To ensure that frequency fVCO obtained by <output frequency
× W> falls within the range of 100 to 400
MHz, set the proper W value by using PLLV[1:0] (D[3:2]/0x301B0C). Lower value is better for low power
consumption.
PLLV[1:0]:PLLV-DividerSetupBitsinthePLLControlRegister(D[3:2]/0x301B0C)
TableIII.1.6.4.1SettingsoftheWValue
PLLV1
1
0
PLLV0
1
0
1
0
W
8
4
2
Notallowed
(Default:0b01=2)
VCokvconstant(VCvalue)
According to the range of fVCO frequencies obtained by <output frequency
× W>, set the VCO Kv circuit
constant (VC value) by using PLLVC[3:0] (D[15:12]/0x301B0C).
PLLVC[3:0]:PLLVCOKvSetupBitsinthePLLControlRegister(D[15:12]/0x301B0C)
TableIII.1.6.4.2SettingsoftheVCValue
PLLVC3
1
0
Other
PLLVC2
0
1
0
fVCo[Mhz]
360<fVCO
≤400
320<fVCO
≤360
280<fVCO
≤320
240<fVCO
≤280
200<fVCO
≤240
160<fVCO
≤200
120<fVCO
≤160
100
≤fVCO≤120
Notallowed
PLLVC1
0
1
0
1
0
PLLVC0
0
1
0
1
0
1
0
1
(Default:0b0001)
LPFresistancevalue(rsvalue)
According to the input clock frequency, set the LPF resistance value (RS value) of the PLL by using
PLLRS[3:0] (D[11:8]/0x301B0C).
PLLrs[3:0]:PLLLPFResistanceSetupBitsinthePLLControlRegister(D[11:8]/0x301B0C)
TableIII.1.6.4.3SettingsoftheRSValue
PLLrs3
1
Other
PLLrs2
0
freFCk[Mhz]
5
≤fREFCK<20
20
≤fREFCK≤150
Notallowed
PLLrs1
1
0
PLLrs0
0
(Default:0b1000)
LPFcapacitancevalue(Csvalue)
Bits to set the LPF capacitance value (CS value) is provided in the CMU control registers, PLLCS[1:0]/
(D[23:22]/0x301B0C). However, do not alter the value of these bits, and leave them as initially set (0b00).
PLLCs[1:0]:PLLLPFCapacitanceSetupBitsinthePLLControlRegister(D[23:22]/0x301B0C)
Chargepumpcurrentvalue(CPvalue)
Bits to set the charge pump current value (CP value) is provided in the CMU control registers, PLLCP[4:0]/
(D[20:16]/0x301B0C). However, do not alter the value of these bits, and leave them as initially set (0b10000).
PLLCP[4:0]:PLLChargePumpCurrentSetupBitsinthePLLControlRegister(D[20:16]/0x301B0C)