|
Take an AC source of ~10 V (sine wave, 50 Hz) and a 1N5408 diode with a 1 kΩ load resistor to ground. During the forward half-cycle (when the diode anode is on the positive half-cycle), the diode opens, and ~9.3 V appears across the resistor (10 V minus ~0.7 V across the diode). During the negative half-cycle (the anode is negative), the diode is closed, the current is ~0, and 0 V across the resistor. We obtain pulsating DC: 50 bursts of ~9.3 V per second, alternating with pauses. If we assemble a bridge instead of one diode, 4 diodes form a complete rectifier. We connect AC (two terminals of the transformer) to the bridge, and the load to the other two terminals of the bridge. In each half-cycle, two diodes conduct, delivering current to a load of the same polarity. The output is a pulsation with a frequency of 100 Hz (for a 50 Hz input) and an amplitude of ~9.3 V peak (minus two drops of 0.7 V on the bridge diodes).
|
