Journal of Korea Multimedia Society (한국멀티미디어학회논문지)

Korea Multimedia Society (한국멀티미디어학회)
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Method for Current-Driving of the Loudspeakers with Class D Audio Power Amplifiers Using Input Signal Pre-Compensation

입력 신호의 전치 보상을 이용한 D 급 음향 전력 증폭기의 스피커 전류 구동 방법

  • Eun, Changsoo (Department of Radio and Information Communications Eng. Chungnam National University) ;
  • Lee, Yu-chil (Kaidas Co., Ltd.)
  • Received : 2018.05.10
  • Accepted : 2018.08.01
  • Published : 2018.09.30
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Abstract

We propose a method for driving loudspeakers from class D audio power amplifiers in current mode, instead of in conventional voltage mode, which was impossible with the feedback circuitry. Unlike analog audio amplifiers, Class D audio power amplifiers have signal delay between the input and output signals, which makes it difficult to apply the feedback circuitry for current-mode driving. The idea of the pre-distortion scheme used for the compensation of the non-linearity of RF power amplifiers is adapted to remedy the impedance variation effect of the loudspeakers for current driving. The method uses the speaker model for the pre-distorter to compensate for the speaker impedance variation with frequency. The simulation and test results confirms the validity of the proposed method.

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References

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