Open AccessHigh bandwidth class B totem pole power amplifier for envelope modulators
Author(s) -
Watkins G.T.
Publication year - 2013
Publication title -
electronics letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.375
H-Index - 146
ISSN - 1350-911X
DOI - 10.1049/el.2012.3994
Subject(s) - amplifier , power bandwidth , rf power amplifier , bandwidth (computing) , electrical engineering , electronic engineering , linear amplifier , engineering , power added efficiency , direct coupled amplifier , operational amplifier , telecommunications
A class B totem pole power amplifier is presented. The amplifier has a small signal bandwidth of 23MHz and is capable of driving a 1MHz sinsuiodal signal into a 7.5Ω load resistance at an output power of 3.7W. When amplifying the AC envelope component of a 20MHz bandwidth 3GPP Long Term Evolution (LTE) signal, 2W is produced into the 7.5Ω load. By optimising the supply rails based on the characteristics of the envelope signal, an efficiency of 31% is achieved. When combined with a switched mode power supply, it forms an envelope modulator that can achieve 61.6% efficiency at 9.3W output power with an output peak‐to‐average power ratio of 8.5dB.