A full wave rectifier converts the entire input AC waveform (both positive and negative halves) into a pulsating DC output. When using a center tapped transformer, a specific number of diodes are required to achieve this rectification.
The standard circuit configuration for a full wave rectifier employing a center-tapped transformer utilizes two diodes. Each diode is placed in series with one half of the secondary winding. During the positive half-cycle of the input AC voltage, one diode conducts, while the other remains off. Conversely, during the negative half-cycle, the second diode conducts, and the first diode is off. This ensures current flows through the load in the same direction for both halves of the input cycle.
Therefore, exactly 2 diodes are needed to construct a full wave rectifier circuit using a center-tapped transformer.