Hi,

If the peak load option is not selected for a design, PIExpert will select the most optimal design for the specification provided. The power supply will be designed to deliver the load power for which it is designed but will not have any significant overload capability.

Since PIExpert computes a design for worst case conditions including part and component tolerances, most power supplies designed will have some overload capability in real life.

If a peak power performance is specifically required, it is important to design a power supply such that it will be able to maintain regulation at output during peak load condition. PIExpert facilitates design of power supplies with the peak load capability.

For a power supply which is not designed for any additional peak load capability, when a pulsed overload is applied, typically its output capacitors will support the overload conditions, however the output voltage will start falling. If the output voltage falls below the regulation limits, that may be unacceptable for some loads.

If the peak load condition exists for several 10's of milliseconds and the power supply is not designed for this peak load condition, its output voltage will fall out of regulation. The loss of regulation wil be detected especially if it is sustained and the power supply could enter the protective "autorestart mode" in which the power supply will undergo a shutdown and a startup if the auto-restart mode is active. So a power supply output will experience a hiccup which could be unacceptable for many loads.

It is therefore important that a power supply be designed for the actual load conditions that it is expected to support and PIExpert will help you with achieving the required design.

Regards

PI-Sarek