Title :
Design of high-efficiency current-mode class-D amplifiers for wireless handsets
Author :
Hung, Tsai-Pi ; Metzger, Andre G. ; Zampardi, Peter J. ; Iwamoto, Masaya ; Asbeck, Peter M.
Author_Institution :
Dept. of Electr. & Comput. Eng., Univ. of California, La Jolla, CA, USA
Abstract :
Design considerations are discussed for current-mode class-D (CMCD) microwave power amplifiers. Factors affecting amplifier efficiency are described analytically and via simulation. Amplifiers are reported that incorporate parallel LC resonators alongside the switching transistors. To reduce parasitic resistance, bond-wires were utilized to implement a high Q inductor in the LC resonator. An experimental CMCD amplifier based on GaAs HBTs is reported, with collector efficiency of 78.5% at an output power of 29.5 dBm (0.89 W) at 700 MHz.
Keywords :
III-V semiconductors; Q-factor; circuit simulation; current-mode circuits; gallium arsenide; gallium compounds; heterojunction bipolar transistors; inductors; microwave power amplifiers; mobile handsets; network synthesis; resonators; 0.89 W; 700 MHz; GaAs HBT; GaInP-GaAs; LC resonator; bond wires; circuit simulation; class-D amplifiers; high Q inductor; high efficiency current mode amplifiers; microwave power amplifiers; network synthesis; parallel LC resonators; parasitic resistance reduction; switching transistors; wireless handsets; Frequency; High power amplifiers; Inductors; Operational amplifiers; Parasitic capacitance; Power amplifiers; Power generation; Radiofrequency amplifiers; Telephone sets; Voltage;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
DOI :
10.1109/TMTT.2004.839327
