Voltage Hold Up

Let us learn how capacitors help to retain the voltage when there is a voltage interruption.

There are requirement in some designs where the voltage need to be hold even though the actual input to the system has gone to zero for a small period. Let us understand how to ensure that the voltage is maintained in that scenario.

Let us go through the power supply scenario in a specific system as shown in block diagram.

Let us assume that the input is OFF for a fraction of 5ms and still the system should work without any power outage. To achieve this scenario the capacitors must be selected such that voltage is hold up for that period of 5ms.