A single-phase direct pulse width modulation (PWM) AC-AC converter is proposed in this paper. The proposed converter has a simple structure and efficient performance to be utilized as an AC voltage buck converter. It is designed with a low number of semiconductor switches and passive components (four switches, one inductor, and one capacitor). The major advantages of the proposed converter can be mentioned as: Only one switch operates during each mode of operation decreasing the circuit losses. It is operated with simple pulse width modulation control and doesn't require a safe-commutation strategy. It does not suffer from input source shoot-through and dead time problems. It retains the common sharing ground of the input and output and can be utilized for voltage sag and swell compensation. Additionally, the proposed converter features are high efficiency, continuous input and output currents, and low filtering requirements. The performance of the proposed circuit is extensively evaluated by using MATLAB/Simulink environment. Moreover, a DSP-based laboratory model is built for physical realization of the proposed converter operation.