Class AB amplifier with simultaneous amplitude and output current tracking

In this paper a new technique is introduced for simultaneous amplitude and output current tracking of class AB amplifier. In the proposed circuit, the output voltage is provided by a class AB amplifier benefiting from the linear characteristic of this amplifier. However, the load current is provided by a class D amplifier in order to increase the efficiency. Furthermore, the class D amplifier provides the supply voltage of class AB amplifier with the capability of amplitude tracking. The proposed technique is simulated using PSpice software. Simulation results show efficiency improvement of at least 6% in comparison to current tracking technique. Also, experimental results are presented to justify the validity of theoretical analysis and simulation results.