1FEATURES
2• Integrated Li-Ion Battery Charger with Power
FET, Thermal Regulation and 28V OVP
• Six Low-Noise LDOs, Two LILO LDOs
– 3 x 300 mA
– 4 x 150 mA
– 1 x 80 mA
• One High Efficiency Synchronous Magnetic
Buck Regulators, IOUT 700 mA
– High Efficiency PFM Mode @low I OUT
– Auto Mode PFM/PWM Switch
– Low Inductance 2.2 μH @ 2 MHz Clock
• I2C-compatible Interface for Controlling LDO
Outputs and Charger Operation
• Thermal Shutdown with Early Warning Alarm
• Under-Voltage Lockout
• 30-bump 3.0 x 2.5 mm DSBGA Package

APPLICATIONS
• Cellular Handsets

KEY SPECIFICATIONS
• 50 mA to 1200 mA Charging Current
• 3.0V to 5.5V Input Voltage Range
• 135 mV typ. Dropout Voltage @ 300 mA LDOs
• 2% (typ.) Output Voltage accuracy on LDOs
• 700 mA (typ.) Buck Regulator

DESCRIPTION
The LP3923 is a fully Integrated Power Management
Unit (PMU) designed for CDMA cellular phones.
The LP3923 PMU contains a fully integrated Li-Ion
battery charger with power FET and over-voltage- protection (OVP), one Buck regulator, 8 low-noise
low-dropout (LDO) voltage regulators, and a high-
speed serial interface to program on/off conditions
and output voltages of individual regulators, and to
read status information of the PMU. Two LILO (low- input, low-output) type LDOs with separate power
input provide an application option for pre-regulated
high efficient power management for longer battery
life.