A new stereo enhancement circuit for class-D amplifier

This paper presents a novel stereo enhancement structure for the surround stereo class-D audio amplifier. The principle of this stereo enhancement scheme has been analyzed. It shows that the amplifier with this proposed circuit have a better live effect than the traditional class-D audio amplifiers. In this circuit, the input audio signal from one channel can be amplified in the two channels at the same time, by a way of cross-coupling. The ratio of gains in the two channels also can be adjusted by changing the external resistance, which improves the stereo effect. A practical implementation in a CMOS 0.18-μm process has been done to validate the theoretical results. When a sine signal with 1 KHz frequency and 100 mV amplitude is applied in one channel, and a DC applied signal in the other, the amplifier demonstrates a gain difference of 9.4 dB.

[1]  Chung-Wei Lin,et al.  A 1.5 bit 5th order CT/DT delta sigma class D amplifier with power efficiency improvement , 2008, 2008 IEEE International Symposium on Circuits and Systems.

[2]  Ville Pulkki,et al.  Virtual Sound Source Positioning Using Vector Base Amplitude Panning , 1997 .

[3]  Andreas Floros,et al.  Stereo Goes Mobile: Spatial Enhancement for Short-distance Loudspeaker Setups , 2012, 2012 Eighth International Conference on Intelligent Information Hiding and Multimedia Signal Processing.

[4]  Mei-Ling Yeh,et al.  A high efficiency filter-less class-D audio power amplifier , 2009, 2009 IEEE 8th International Conference on ASIC.

[5]  Andreas Floros,et al.  Spatial enhancement for immersive stereo audio applications , 2011, 2011 17th International Conference on Digital Signal Processing (DSP).

[6]  Chun Wei Lin,et al.  Enhanced design of filterless class-D audio amplifier , 2009, 2009 Design, Automation & Test in Europe Conference & Exhibition.