Versatility, Bandwidth and Efficiency: Digital GaN-Based Switch-Mode Supply Modulators
48th European Microwave Conference (EuMC 2018), Madrid, Spain, Sep. 25-27, pp. 523-526 (2018).
Copyright © 2018 EuMA. All rights reserved. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the EuMA.
In this paper the versatility of ultra-fast and, at the same time, high-power capable digital electronics is demonstrated. An electronic switch based on 0.25µm GaN HEMT technology, originally designed as a digital microwave power amplifier, is reconfigured for different applications with the goal of extending the modulation bandwidth and efficiency of envelope tracking concepts. When configured as a DC/DC converter for continuous supply modulation a modulation bandwidth of 300MHz is demonstrated using a clock frequency of 9.4 GHz for the low-pass delta sigma modulator. When configured as a class-G discrete supply modulator, excellent rise and fall times below 112 ps (10% to 90%) are achieved. This allows minimum pulse widths below 1 ns and IQ modulation bandwidth in the GHz range.
Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik, Berlin, Germany
DC-DC power converters, envelope tracking, RF power amplifiers, switching circuits, supply modulation.