Patent attributes
Apparatus and methods for phase compensation in power amplifiers are disclosed herein. In certain implementations, a power amplifier includes an input stage, an output stage, an envelope tracker, and a compensation circuit. The input and output stages are cascaded and amplify an input RF signal to generate an amplified output RF signal. The envelope tracker generates a power amplifier supply voltage for at least the output stage based on an envelope of the input RF signal. The compensation circuit compensates for changes in input impedance of the output stage associated with changes in the voltage level of the power amplifier supply voltage. By including the compensation circuit, a variation in the power amplifier's phase delay versus input power can be reduced, thereby leading to an improvement in the power amplifier's phase distortion (AM/PM).
