Two-phase buck DC-AC converter as dynamic power supply for amplitude-modulated Class-DE Power Amplifier

This paper presents an analysis of the two-phase buck converter functioning as a dynamic power supply for Class-DE radio-frequency (RF) power amplifier (PA). The equations necessary to design the buck converter providing an ac output voltage with a dc offset is presented. It is shown that the maximum inductor current ripple in the buck converter occurs when the output voltage is at its nominal value. Consequently, the expression for the minimum value of the inductance as a function of efficiency needed for the converter to operate in continuous-conduction mode is derived. Additionally, the necessary equations needed to design the Class-DE RFPA are provided. A design example of a two-phase buck dc-ac converter with Class-DE RFPA as a dynamic load is considered. Simulation results are presented to validate the theoretical results.

[1]  M. Hoyerby,et al.  Ultrafast Tracking Power Supply With Fourth-Order Output Filter and Fixed-Frequency Hysteretic Control , 2008, IEEE Transactions on Power Electronics.

[2]  M. Kazimierczuk.  Pulse-Width Modulated DC-DC Power Converters: Kazimierczuk/Pulse-width Modulated DC-DC Power Converters , 2008 .

[3]  D. Maksimović,et al.  High-Frequency PWM Buck Converters Using GaN-on-SiC HEMTs , 2014, IEEE Transactions on Power Electronics.

[4]  Marian K. Kazimierczuk,et al.  Open loop small-signal control-to-output transfer function of PWM buck converter for CCM: modeling and measurements , 1996, Proceedings of 8th Mediterranean Electrotechnical Conference on Industrial Applications in Power Systems, Computer Science and Telecommunications (MELECON 96).

[5]  O. Garcia,et al.  Multiphase buck converter with minimum time control strategy for RF envelope modulation , 2011, 2011 Twenty-Sixth Annual IEEE Applied Power Electronics Conference and Exposition (APEC).

[6]  Marian K. Kazimierczuk,et al.  Two-phase buck converter as a dynamic power supply for RF power amplifier applications , 2013, 2013 IEEE 56th International Midwest Symposium on Circuits and Systems (MWSCAS).

[7]  Peng Xu,et al.  Multiphase coupled-buck converter-a novel high efficient 12 V voltage regulator module , 2003 .