Class D Switching Power Amplifier with a Filter under Load Mismatch Conditions
Oleg V. Varlamov, V. N. Gromorushkin
Abstract
RF push-pull switching mode power amplifiers (SMPA) with a filter is one of the promising options for use as an output stage of IoT devices operating in 5G networks. Small sizes of IoT devices may cause work on a mismatched antenna. This article analyzes the energy characteristics of a Class D switching power amplifier with a filter for two configurations: voltage mode and current mode under load mismatch conditions. Based on the analysis of time diagrams, integral equations are written, the solution of which allows us to derive calculation formulas. The results of calculations are presented. It is shown that the effective use of push-pull SMPA with a filter in the output stages of the transmitters is possible with load VSWR not more than 1.25 ... 1.43.