Patent ID: 8072270

Claim:
A Radio Frequency (RF) power amplifier comprising: a transconductance stage having a transistor with an RF signal input at its gate; a cascode stage having at least one cascode transistor, the cascode stage coupled in series with the transconductance stage between a battery voltage node and ground, the cascode stage having an RF signal output and at least one bias input to the at least one cascode transistor; and bias circuitry comprising: a first current minor having first and second transistors with sources coupled to ground and operable to receive a reference current at a drain of the first transistor; a second current minor having first and second transistors with sources coupled to a battery supply voltage; a third current mirror having first and second transistors with sources coupled to drains of the first and second transistors of the second current minor, respectively; a biasing transistor coupled between the second transistor of the first current minor and the first transistor of the third current minor and operable to receive a tuning input voltage at its gate; and a resistive element coupled between the second transistor of the third current mirror and ground, a bias voltage produced at a connection of the resistive element and the second transistor of the third current mirror.