Over Voltage Protection Circuit Power Supply

Most power supplies use an over voltage protection circuit to prevent damage to the electronic components.

Over voltage protection circuit power supply.

With the zener diode voltage chosen to be slightly above the maximum rail voltage under normal conditions it will not conduct. In its simplest form it can be provided by using a zener diode placed across the output of the regulated power supply. The crowbar circuit must be mounted between power supply and the protected device. When the power supply voltage increases too much a thyristor shortcircuit the output.

This is a sequel to our anatomy of switching power supplies tutorial and we are going to explore in depth all power supply protections like over voltage ovp under voltage uvp. The over voltage protection circuit is based on brute force. In some situations where the input voltage is higher than expected we always use an overvoltage protection or crowbar protection circuit. The circuit has a few components it is very easy to build and will protect your electric equipment againg overvoltages.

Overvoltage protection is a power supply features which cutoffs the supply whenever input voltage exceeds the preset value. Crowbar protection circuit is a type of overvoltage protection which is most commonly used in electronic circuits. Another very simple form of over voltage protection uses an approach called voltage clamping.