1FEATURES

2• 2MHz (typ.) PWM Switching Frequency

• Operates from a Single Li-Ion Cell (2.7V to

5.5V)

• Adjustable Output Voltage (0.8V to 3.6V) DC-

DC

• High-Efficiency Synchronous Buck Converter

• 300mA Maximum Load Capability (PWM Mode)

• 500mA Maximum Load Capability (Bypass

mode)

• PWM, Forced and Automatic Bypass Mode

• 3 Low-Dropout and Fast Transient Response

LDOs

• 16-pin DSBGA Package

• Current Overload Protection

• Thermal Overload Protection

APPLICATIONS

• Cellular Phones

• Hand-Held Radios

• Battery Powered RF Devices

DESCRIPTION

The LM3280 is a multi-functional Power Management

Unit, optimized for low-power handheld applications

such as Cellular Phones.

The LM3280 incorporates three low-dropout LDO

voltage regulators and one step down PWM DC-DC converter with an internal Bypass FET. The step

down converter's output voltage can be set using an

analog input (VCON) for optimizing efficiency of the RF

PA at various power levels. The LDO operates a

nominal output voltage of 2.85V and maximum load current capability of 20mA for a reference voltage

required by linear RF power amplifiers. The LM3280

additionally features a separate enable pin for each

output.

The LM3280 is available in a 16-pin lead free DSBGA

package.