Title :
A 20MS/s buck/boost supply modulator for envelope tracking applications with direct digital interface
Author :
Shang-Hsien Yang ; Chin-Long Wey ; Ke-Horng Chen ; Ying-Hsi Lin ; Jing-Jia Chen ; Tsung-Yen Tsai ; Chao-Cheng Lee
Author_Institution :
Nat. Chiao Tung Univ., Hsinchu, Taiwan
Abstract :
A buck/boost supply modulator (BBSM) is proposed for 4G LTE RF power amplifier (RF-PA) envelope tracking applications. The H-bridges used in non-inverting buck/boost converters are metamorphosed into the current sources and switches of a 4-bit current-steering DAC-like supply modulator. Fast tracking speed is achieved through its inherent open-loop topology, while the direct digital interface provides easy control and integration with digital LTE baseband SoCs. The proposed BBSM is capable of delivering peak power of 2.8W at 20MS/s, with a peak efficiency of 75 %.
Keywords :
digital-analogue conversion; modulators; power convertors; radiofrequency power amplifiers; system-on-chip; 4G LTE RF power amplifier envelope tracking applications; 4G LTE RF-PA envelope tracking applications; BBSM; H-bridges; buck-boost supply modulator; current sources; current-steering DAC-like supply modulator; digital LTE baseband SoC; direct digital interface; efficiency 75 percent; open-loop topology; power 2.8 W; word length 4 bit; Bandwidth; Inductors; Linearity; Long Term Evolution; Modulation; Power amplifiers; Radio frequency; Supply modulator; envelope tracking; non-inverting buck/boost converter;
Conference_Titel :
Solid-State Circuits Conference (A-SSCC), 2014 IEEE Asian
Conference_Location :
KaoHsiung
Print_ISBN :
978-1-4799-4090-5
DOI :
10.1109/ASSCC.2014.7008863
