LP3907SQ-JXQX NSC [National Semiconductor], LP3907SQ-JXQX Datasheet - Page 28

• Manufacturer Part Number: LP3907SQ-JXQX
• Description: Dual High-Current Step-Down DC/DC and Dual Linear Regulator with I2C Compatible Interface
• Manufacturer: NSC [National Semiconductor]

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LP3907 Control Registers
INTERRUPT STATUS REGISTER (ISRA) 0X02
This register informs the System Engineer of the temperature status of the chip.
CONTROL 1 REGISTER (SCR1) 0X07
This register allows the user to select the preset delay sequence for power-on timing, to switch between PFM and PWM mode for
the bucks, and also to select between an internal and external clock for the bucks.
Name
Access
Data
Reset
Name
Access —
Data
Reset
Register
Address
0x2A
0x2B
0x3A
0x02
0x07
0x10
0x11
0x20
0x23
0x24
0x25
0x29
0x38
0x39
D7
—
Reserved
0
BKLDOEN
BKLDOSR
LDO1VCR
LDO2VCR
Register
B1TV1
B1TV2
B2TV1
B2TV2
Name
VCCR
BFCR
SCR1
B1RC
B2RC
ICRA
D7-2
—
—
Reserved
0
D6-4
EN_DLY
R/W
Selects the preset
delay sequence
from EN_T assertion
(shown below)
010
Read/
Write
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R
R
D1
Temp 125°C
R
Status bit for thermal warning
PMIC T>125°C
0
0 – PMIC Temp. < 125°C
1 – PMIC Temp. > 125°C
Interrupt Status Register A
System Control 1 Register
Buck and LDO Output Voltage Enable Register
Buck and LDO Output Voltage Status Register
Voltage Change Control Register 1
Buck1 Target Voltage 1 Register
Buck1 Target Voltage 2 Register
Buck1 Ramp Control
Buck2 Target Voltage 1 Register
Buck2 Target Voltage 2 Register
Buck2 Ramp Control
Buck Function Register
LDO1 Voltage control Registers
LDO2 Voltage control Registers
D3
—
—
Reserved
1
D2
FPWM2
R/W
Buck2 PWM /PFM
Mode select
0 – Auto Switch PFM -
PWM operation
1 – PWM Mode Only
0
28
Register Description
D1
FPWM1
R/W
Buck 1 PWM /PFM
Mode select
0 – Auto Switch PFM -
PWM operation
1 – PWM Mode Only
0
D0
ECEN
R/W
Reserved
0
D0
—
—
Reserved
0