Temperature-compensated power sensing circuit for power amplifiers

Abstract

An amplifier circuit for amplifying radio frequency signals having temperature compensation and bias compensation includes a radio frequency power amplifier that receives an input radio frequency signal and outputs an amplified radio frequency signal, and a first transistor performing as a detector diode with its collector and base connected. The base of the first transistor receives the amplified radio frequency signal from the power amplifier, a second DC bias input signal from a regulated DC source, and a third power-sensing signal. The amplifier circuit further includes a second transistor to amplify the DC component of the RF signal from the base of the first transistor. The base of the second transistor is coupled to the base of the first transistor. The collector of the second transistor outputs the power-sensing signal, which is coupled to the regulated DC source through a resistor.

Dependencies are inferred from the claim text.