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.