Three schemes for improving the efficiency of the power amplifier were introduced: Doherty technology, envelope elimination and recovery (EER) technology, and envelope tracking (ET) technology. It is shown that ET technology has significant advantages in term of performance and reliability. In order to save the power loss of envelope tracking technology and improve the performance of envelope tracking system, a hybrid ET power supply was proposed. Simulation and experimental results demonstrate that the proposed ET power supply achieves an output power of 1 W on a 5 Ω load resistance with a power efficiency of 60%. The efficiency and output linearity can keep stable under various input signal, which make it suitable for power amplifier applications.