Design of digitally controlled envelope tracking power supply with gan transistor for rf power amplifiers

Wireless communication, which is used in mobile phones, modems, base stations and many other areas has gained importance with increasing demand and developing technology. RF power amplifiers are one of the most important blocks in wireless communication. Power amplifiers consume the most power in RF systems. Therefore, efficiency is one of the most important parameters in power amplifier design. Classical power amplifiers are not efficient. Envelope tracking is one of the voltage modulation techniques that is used to increase efficiency in power amplifiers. In this method, the power source feeding the power amplifier creates an output voltage according to the needs of the RF system by increasing and decreasing the output voltage. In this study, envelope tracking power supply design is explained. This supply is capable of operating with 9-12V input voltage, has 750 KHz switching frequency, follows reference signal up to 5kHz, supplies 1A output current and 5V output voltage. The power supply is a design with synchronous buck converter topology. Also this study includes digital control design providing flexible solutions, use of GaN (Gallium Nitride) transistors that work more efficiently at high speeds and various analyzes. Keywords: Buck converter, Digital control, Envelope tracking, GaN transistor, Power amplifiers