Sliding mode controlled half bridge audio amplifier using single power supply

This paper proposes a sliding mode controlled half-bridge audio amplifier using a single power supply for mid power audio application. This half bridge configuration, which is compact and efficient, acts as a band-pass filter for full audio frequencies. Sliding mode control technique is used which obviates requirement of an explicit carrier signal and offers high disturbance rejection. A 10/20 W, 20 Hz to 20 kHz amplifier with 8/4 Ω speaker load is developed and tested. Frequency response of the amplifier confirms the band pass behavior of amplifier. For linearity verification, THD plots for amplitude and frequency variations obtained from the experimental prototype are presented.