
LP3972 CONTROL REGISTER
Register Address
Register Name
Read/Write
Register Description
8h’07
SCR
R/W
System Control Register
8h’10
OVER1
R/W
Output Voltage Enable Register 1
8h’11
OVSR1
R
Output Voltage Status Register 1
8h’12
OVER2
R/W
Output Voltage Enable Register 2
8h’13
OVSR2
R
Output Voltage Status Register 2
8h’20
V
CC1
R/W
Voltage Change Control Register 1
8h’23
ADTV1
R/W
Buck1 Target Voltage 1 Register
8h’24
ADTV2
R/W
Buck1 DVM Target Voltage 2 Register
8h’25
AVRC
R/W
V
CC_APPS Voltage Ramp Control
8h’26
CDTC1
W
Dummy Register
8h’27
CDTC2
W
Dummy Register
8h’29
SDTV1
R/W
LDO5 Target Voltage 1
8h’2A
SDTV2
R/W
LDO5 Target Voltage 2
8h’32
MDTV1
R/W
LDO1 Target Voltage 1 Register
8h’33
MDTV2
R/W
LDO1 Voltage 2 Register
8h’39
L2VCR
R/W
LDO2 Voltage Control Registers
8h’3A
L34VCR
R/W
LDO3 & LDO4 Voltage Control Registers
8h’80
SCR1
R/W
System Control Register 1
8h’81
SCR2
R/W
System Control Register 2
8h’82
OEN3
R/W
Output Voltage Enable Register 3
8h’83
OSR3
R/W
Output Voltage Status Register 3
8h’84
LOER4
R/W
Output Voltage Enable Register 3
8h’85
B2TV
R/W
V
CC_Buck2 Target Voltage
8h’86
B3TV
R/W
V
CC_Buck3 Target Voltage
8h’87
B32RC
R/W
Buck 3:2 Voltage Ramp Control
8h’88
ISRA
R
Interrupt Status Register A
8h’89
BCCR
R/W
Backup Battery Charger Control Register
8h’8E
II1RR
R
Internal 1 Revision Register
8h’8F
II2RR
R
Internal 2 Revision Register
SERIAL INTERFACE REGISTER SELECTION CODES (Bold face voltages are default values)
System Control Status Register
Register is an 8-bit register which specifies the control bits for the PMIC clocks. This register works in conjunction with the SYNC
pin where an external clock PLL buffer operating at 13 MHz is synchronized with the oscillators of the buck converters.
System Control Register (SCR) 8h’07
Bit
7
6
5
4
3
2
1
0
Designation
Reserved
CLK_SCL
Reset Value
0
System Control Register (SCR) 8h’07 Definitions
Bit
Access
Name
Description
7-1
—
Reserved
0
R/W
CLK_SCL
External Clock Select
0 = Internal Oscillator clock for Buck Converters
1 = External 13 MHz Oscillator clock for Buck Converters
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LP3972