For further information contact your local STMicroelectronics sales office.

May 2014

DocID026381 Rev 1

1/4

STEVAL-ISA153V1

12 V, 15 W (20 W peak) isolated flyback converter

based on the VIPER38LE

Data brief

Features

frequency: 50 - 60 Hz

• Output voltage/current: 12 V/1.25 A (1.65 A

peak)

• Very compact size

• Standby mains consumption: lower than 30

• Minimum active mode efficiency: 81.55%

• Minimum active mode at 10% load efficiency:

71.55%

• EMI: in accordance with EN55022-Class-B

• RoHS compliant

Description

The STEVAL-ISA153V1 product evaluation board

implements a 12 V/1.25 A, 15 W (20 W peak)

isolated flyback wide-range mains developed for

general-purpose applications.

The core of the application is the VIPER38LE, the

latest offline converter from the VIPerPlus family.

The device is a high-voltage converter that

smartly integrates an 800 V rugged power

MOSFET with PWM current-mode control. The

device features an adjustable extra power timer

(EPT) that enables the IC to sustain overload

conditions for a few seconds.

The main characteristics of the evaluation board

are its small size and minimal BOM, high

efficiency and low standby consumption.

Extremely low consumption under no-load

conditions is ensured thanks to burst mode

operation which reduces the average switching

frequency and minimizes all frequency-related

losses.

The VIPER38LE operates at a fixed 60 kHz

frequency. Frequency jittering is implemented,

which helps the application meet electromagnetic

disturbance standards.

The IC includes high-level protection features

such as dual-level OCP, output overvoltage,

short-circuit, and thermal shutdown with

hysteresis. After removal of a fault condition, the

IC is automatically restarted.

www.st.com