STEVAL-ISA007V1: 150W, 3PH, 24V @ 6A, 5V @ 75mA

This application note deals with the design of a 3-Phase auxiliary power supply for 150W dual output SMPS, using the L5991 PWM driver and the STC08DE150 ESBT as main switch. The combination of these ST's parts aims at obtaining a high efficiency solution for high DC input voltage, typical requirement of any three phase application.

The L5991 driver is an upgraded version of the UC384X current mode PWM driver. It boasts some very interesting additional features.

Standardization towards "universal input" is reflected in more stressful conditions for the power transistor used as the main switch both in terms of blocking voltage or current capability.

Since almost all auxiliary power supplies are based on fly-back converters, the need for a blocking voltage as high as 1500V and over, coupled with high switching frequency operations, make the ESBTs the perfect choice for such power supplies.

The STC08DE150HV, in conjunction with the PWM L5991, perfectly fulfills the requirements and brings high efficiency to the system.