A power amplifier controller circuit for controlling a power amplifier, the power amplifier coupled to receive and amplify an input signal to generate an output signal, the input signal being modulated and having varying amplitude, the power amplifier controller circuit comprising: an amplitude control loop including: a variable gain amplifier, the variable gain amplifier receiving and amplifying a radio frequency, RF, input signal to generate the input signal to the power amplifier; an amplitude comparator comparing an amplitude of the RF input signal with the attenuated amplitude of the output signal of the power amplifier to generate an amplitude correction signal indicative of an amplitude difference between an amplitude of the RF input signal and an attenuated amplitude of the output signal of the power amplifier; a first power supply with a first efficiency, the first power supply receiving a first portion of the amplitude correction signal in a first frequency range and generating a first adjusted supply output based upon the first portion of the amplitude correction signal; and a second power supply with a second efficiency higher than the first efficiency, the second power supply receiving a second portion of the amplitude correction signal in a second frequency range lower than the first frequency range and generating a second adjusted supply output based upon the second portion of the amplitude correction signal, a combination of the first adjusted supply output and the second adjusted supply output forming a supply voltage or bias to the power amplifier, the variable gain amplifier being configured to adjust an amplitude of the input signal to the power amplifier based upon a gain control signal derived from the amplitude correction signal, the gain control signal having a bandwidth that is significantly different than a bandwidth of the supply voltage or bias to the power amplifier such that the bandwidth of the supply voltage or bias is reduced relative to the bandwidth of the gain control signal. an amplitude control loop including: a variable gain amplifier, the variable gain amplifier receiving and amplifying a radio frequency, RF, input signal to generate the input signal to the power amplifier; an amplitude comparator comparing an amplitude of the RF input signal with the attenuated amplitude of the output signal of the power amplifier to generate an amplitude correction signal indicative of an amplitude difference between an amplitude of the RF input signal and an attenuated amplitude of the output signal of the power amplifier; a first power supply with a first efficiency, the first power supply receiving a first portion of the amplitude correction signal in a first frequency range and generating a first adjusted supply output based upon the first portion of the amplitude correction signal; and a second power supply with a second efficiency higher than the first efficiency, the second power supply receiving a second portion of the amplitude correction signal in a second frequency range lower than the first frequency range and generating a second adjusted supply output based upon the second portion of the amplitude correction signal, a combination of the first adjusted supply output and the second adjusted supply output forming a supply voltage or bias to the power amplifier, the variable gain amplifier being configured to adjust an amplitude of the input signal to the power amplifier based upon a gain control signal derived from the amplitude correction signal, the gain control signal having a bandwidth that is significantly different than a bandwidth of the supply voltage or bias to the power amplifier such that the bandwidth of the supply voltage or bias is reduced relative to the bandwidth of the gain control signal. a variable gain amplifier, the variable gain amplifier receiving and amplifying a radio frequency, RF, input signal to generate the input signal to the power amplifier; an amplitude comparator comparing an amplitude of the RF input signal with the attenuated amplitude of the output signal of the power amplifier to generate an amplitude correction signal indicative of an amplitude difference between an amplitude of the RF input signal and an attenuated amplitude of the output signal of the power amplifier; a first power supply with a first efficiency, the first power supply receiving a first portion of the amplitude correction signal in a first frequency range and generating a first adjusted supply output based upon the first portion of the amplitude correction signal; and a second power supply with a second efficiency higher than the first efficiency, the second power supply receiving a second portion of the amplitude correction signal in a second frequency range lower than the first frequency range and generating a second adjusted supply output based upon the second portion of the amplitude correction signal, a combination of the first adjusted supply output and the second adjusted supply output forming a supply voltage or bias to the power amplifier, the variable gain amplifier being configured to adjust an amplitude of the input signal to the power amplifier based upon a gain control signal derived from the amplitude correction signal, the gain control signal having a bandwidth that is significantly different than a bandwidth of the supply voltage or bias to the power amplifier such that the bandwidth of the supply voltage or bias is reduced relative to the bandwidth of the gain control signal.