Minimizing Crosstalk in Self Oscillating Switch Mode Audio Power Amplifiers

The varying switching frequencies of self oscillating switch mode audio amplifiers have been known to cause interchannel intermodulation disturbances in multi channel configurations. This crosstalk phenomenon has a negative impact on the audio performance. The goal of this paper is to present a method to minimize this phenomenon by improving the integrity of the various power distribution systems of the amplifier.

The method is then applied to an amplifier built for this investigation. The results show that the crosstalk is suppressed with 30 dB, but is not entirely eliminated by the implementation presented. Future work could include further refinement of the implementation of the concepts, electromagnetic interference investigations or PCB design.