A switching power amplifier with feedback for improving total harmonic distortion

  • Chia-Hsiung Kao
  • Ping-Yu Tsai
  • Wen-Pin Lin
  • Yao-Jen Chuang


A high efficiency and low distortion and switching power amplifier is proposed. We use feedback to reduce the total harmonic distortion (THD) and the DC output bias current. The experimental results show that the proposed circuit has 0.24% total harmonic distortion and 91% power efficiency while the DC output bias current is 12 μA at 1.5 V supply voltage.


Efficiency Distortion Hearing aids 



The authors would like to thank the national chip implementation center (CIC) for the chip fabrication.


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Copyright information

© Springer Science+Business Media, LLC 2007

Authors and Affiliations

  • Chia-Hsiung Kao
    • 1
  • Ping-Yu Tsai
    • 1
  • Wen-Pin Lin
    • 1
  • Yao-Jen Chuang
    • 1
  1. 1. National Sun Yat-Sen University KaohsiungTaiwan

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