STEVAL-ISA019V2: 80W, 24V @ 3.3A, 160 ~ 550VAC

The purpose of this application note is to explain the design of an 80 W 3-phase auxiliary power supply for motor drives and welding applications. To reach a high level system in terms of both efficiency and cost, the L6565 PWM controller has been selected as well as the STC04IE170HV as the main switch. The combination of these STMicroelectronics parts provides a highly efficient solution for high DC input voltage, a typical requirement of any three-phase application.

The L6565 driver is a variable frequency PWM driver suitable for a design flyback converter working in quasi-resonant mode. It also includes some very useful additional features.

All the design choices are thoroughly discussed to allow the user to adapt the project to specific needs. The input voltage can also be extended up to 1000 VDC as enough margin exists to do so. Finally, the experimental results are analyzed to better understand the benefits offered by the use of ESBT in this application.

* Based on eval Board STEVAL-ISA019V2