AN2528 Datasheet, PDF (1/21 Pages) Freescale Semiconductor, Inc – Standard Space Vector Modulation TPU Function Set (svmStd)

AN2528
Application note
Very wide input voltage range 6 W SMPS for metering
Introduction
This document presents the design of a universal input power supply for metering
applications. The design is mainly based on the following ST parts: an L6565 PWM driver
and STC04IE170HP as the main switch. It is linked with the release of the STEVAL-
IP001Vxx demo board (see Figure 1 below). The design is a complete solution for a 5 W
single output SMPS, which is widely used as a power supply in metering applications.
However the design method can be applied to an SMPS suitable for other applications
working on a three-phase mains and it can easily be upgraded for higher output power.
The ESBT base driving circuit as well as guidelines for the optimization of the power
dissipation are given.
The influence of parasitic capacitances of the transformer on the ESBT is also explained in
detail.
Finally, the most important waveforms and thermal results are given in Section 5 and
Section 6. They demonstrate the benefits of using a QR flyback with ESBT.
Refer to AN1889 and AN2254 for the overall design of an auxiliary power supply using
ESBT in flyback QR with L6565, while refer to AN2454 for the small signal power switch
model with all parasitic components.
Figure 1. STEVAL-ISA030V1
July 2007
Rev 1
1/21
www.st.com