GENERAL DESCRIPTION
The ML2731 is a power amplifier (PA) bias controller with support circuits for a typical radio transceiver. The IC integrates a PA bias controller, a PA DC switch, a crystal oscillator circuit, a negative voltage generator and two voltage regulators. It can be used with GaAs FETs and silicon bipolar devices.

FEATURES
■ Sets PA current and power output using a bias control loop
■ Integrates a PA DC supply switch
■ Prevents PA power-on if negative voltage is not present
■ Integrates all circuits needed for supporting a crystal oscillator with 10MHz to 40MHz frequency range
■ Incorporates a fast starting, high switching frequency,
■egative voltage generator requiring only small ceramic capacitors
■ Contains voltage regulators for an oscillator, a negative voltage generator and a 50mA 3.0V LDO output
■ Requires less than 1mA of current when powered down
■ Supply voltage ranges from 3.3V to 5.5V

APPLICATIONS
■ Cellular and Cordless Radios
■ WLAN Radios
■ Radios with GaAs FET Power Amplifiers
■ Fixed and Mobile radio transceivers