Data Brief

For further information contact your local STMicroelectronics sales office

March 2006

Rev 1

1/5

5

STEVAL-ISA006V1

6W Non-isolated fly-back topology power supply

with VIPer12AS

Features

■

Switch mode general purpose power supply

■

Input: 90 to 264Vac @ 50/60Hz

■

Main Output (regulated): 5V, 500mA @ 50/

60Hz

■

Second output: 15V, 200mA

■

Output power (pick): 5.5W

Reference design genaral

description

This reference design is an auxiliary power supply

based on the VIPer12AS monolithic device and

can be used to produce multiple non isolated

positive or negative voltage outputs.

This solution is based on an offline discontinuous

current mode fly-back converter without isolation

between input and output. The fly-back topology

allows the exploitation of the VIPer12AS current

capability when compared with the buck converter

based power supply. To ensure power supply low

cost, the isolation between input and output is not

provided. This greatly simplifies the transformer

design and production. The VIPer12AS

incorporates the PWM controller with a 60kHz

internal oscillator and the vertical Power MOSFET

switch in a SO-8 package. The presented power

supply has four variants. All the variants have

been incorporated in the presented reference

board through different assembly options.

ST Components

■

VIPer12AS off-line SMPS primary

■

STPR120A diode, fast recovery trr =25ns 200V

1A SMA

■

STPS1L40A diode, schottky, 40V 1A,

■

TS2431ILT programmable shunt voltage

reference

STEVAL-ISA006V1

www.st.com