Draw a circuit diagram of a full-wave rectifier using p-n junction diodes. Explain its working and show the input-output waveforms.

Working: Suppose the input voltage to A w.r.t centre top at any instant is positive. At that instant voltage at B being out of phase will be negative. So, diode $\displaystyle \mathrm{D}_{1}$ gets forward biased and conducts while $\displaystyle \mathrm{D}_{2}$ being reverse biased is not conducting. Hence, during this positive half cycle we get an output current and output voltage across the load. When the voltage at A becomes negative w.r.t centre top, the voltage at B would be positive, the diode $\displaystyle \mathrm{D}_{1}$, would not conduct but $\displaystyle \mathrm{D}_{2}$ conduct and giving an output current and voltage across the load. Input and output wave form: