JSSC 2021第10期RF & WirelessBuck Converter

An Envelope Tracking Supply Modulator Utilizing a GaN-Based Integrated Four-Phase Switching Converter and Average Power Tracking-Based Switch Sizing With 85.7% Efﬁciency for 5G NR Power Ampliﬁer Y a-Ting Hsu, Zong-Yi Lin, Jia-Jyun Lee

提出一种基于GaN器件的四相快速降压转换器，用于5G NR包络跟踪，峰值效率达85.7%。

3.5W, 85.7% peak efficiency, NR-130MHz

包络跟踪GaN器件四相转换器5G NR线性放大器

▸采用GaN器件实现四相快速降压转换器

▸通过信号整形生成APT控制信号以提高轻载效率

▸使用高带宽低损耗线性放大器提供快速跟踪能力

Abstract

This article proposes a supply modulator (SM) that uses high switching frequency gallium-nitride (GaN) devices to achieve a four-phase fast step-down converter for the fast-tracking ability of the envelope tracking (ET). The ET signal is reshaped to generate an average power tracking (APT)- based signal to control the size of GaN switches to further increase light-load efﬁciency due to reduced switching loss. Moreover, a high-bandwidth and low-loss linear ampliﬁer (LA) is used to supply the power ampliﬁer (PA) to sufﬁciently provide fast-tracking speed for 5th generation (5G) NR ET. At a power of 3.5 W for 5G mobile phones, the peak efﬁciency that is tested with NR −130 MHz in the ET mode is as high as 85.7% over a wide load range.