May 2012

Doc ID 17220 Rev 2

1/14

UM0920

User manual

4 W non-isolated, wide input-voltage range SMPS demonstration

board based on the VIPer16

Introduction

The purpose of this document is to provide information for the STEVAL-ISA071V2 switched

mode power supply (SMPS) demonstration board. The STEVAL-ISA071V2 is a non-isolated

SMPS capable of delivering a 4 W output over a wide input voltage range, and is designed

for a mains application requiring -5 V and +7 V, referred to neutral. The basic concepts used

in this design can also be applied for higher power outputs or different voltage ranges.

The SMPS generates outputs of 5 V and 12 V, referred to the output marked -5 V. The 5 V is

dedicated to supplying an MCU. This configuration allows the use of the MCU to directly

drive a Triac (referred to neutral). The 12 V output is used to supply additional circuits

(relays, OA, etc.).

This document contains a fundamental technical description of the demonstration board

(schematic diagram, PCB details and bill of materials) and basic measurements (load

regulation, efficiency, standby behavior and EMI data).

Figure 1.

STEVAL-ISA071V2 board

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