Common mode voltage dynamic modulation circuit, method thereof and class-D audio power amplifier
AssigneeSuzhou ACME Semi Co.Ltd.
InventorShuangxi Ding
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Abstract
The disclosure provides a common mode voltage dynamic modulation circuit, a method thereof and a class-D audio power amplifier. The modulation circuit includes: a signal input terminal and a common mode voltage dynamic adjustment module. The signal input terminal is used to receive an audio signal and output a differential audio signal to the common mode voltage dynamic adjustment module. The common mode voltage dynamic adjustment module is used to dynamically adjust a common mode voltage of the differential audio signal according to a preset static common mode bias and a normalized processing result of a swing of the audio signal, track an amplitude of an input audio signal in real time and obtain a continuously adjusted common mode voltage.
Claims13
A common mode voltage dynamic modulation circuit, comprising a signal input terminal and a common mode voltage dynamic adjustment module, wherein
- the signal input terminal is configured to receive an audio signal and output a differential audio signal to the common mode voltage dynamic adjustment module;
- the common mode voltage dynamic adjustment module is configured to dynamically adjust a common mode voltage of the differential audio signal according to a preset static common mode bias and a normalized processing result of a swing of the audio signal to obtain a current common mode voltage;
- an expression of the current common mode voltage after normalization is:
- VCOM/VTRI=1−abs(VIN)/VTRI−α;
- VCOM/VTRI is the current common mode voltage after normalization, abs (VIN)/VTRI is the swing of the audio signal after normalization, abs (VIN) is an absolute value of an input voltage VIN, VCOM is the current common mode voltage, VTRI is a maximum voltage of a triangular wave, and α is the preset static common mode bias.
Dependencies are inferred from the claim text.