Circuitry, which includes a linear amplifier, is disclosed. The linear amplifier has a linear amplifier output and includes an input amplifier stage and an output amplifier stage. The output amplifier stage at least partially provides an envelope power supply voltage to a radio frequency (RF) power amplifier (PA) via an envelope power supply output using a selected one of a group of linear amplifier power supply signals. The group of linear amplifier power supply signals includes at least a first bi-directional power supply signal. The input amplifier stage selects the one of the group of linear amplifier power supply signals based on the envelope power supply voltage and a setpoint of the envelope power supply voltage.