Capacitor Smoothing

Smoothing

1. In the circuit above, the `one-way' direct current flows in a series of surges with brief periods of zero current in between. 
2. These surges can be partly smoothed out by connecting a large capacitor across the load.
3. The capacitor charges up when current flows from the diode, then discharges through the load when the current from the diode is zero. 
4. Smoothed in this way, the current through the load is similar to the steady direct current which would flow from a battery.