STMicroelectronics STEVAL-ISA153V1

Overview

STEVAL-ISA153V1 from STMicroelectronics is an evaluation board implementing a 12 V, 15 W (20 W peak) isolated flyback converter using the VIPER38LE offline controller IC, supporting universal AC input (90–265 VAC, 50–60 Hz), achieving ≥81.55% efficiency at full load and <30 mW no-load consumption, designed for compact, low-BOM power supply development in industrial and consumer applications.

For engineers reviewing the STEVAL-ISA153V1 datasheet, STEVAL-ISA153V1 schematic, STEVAL-ISA153V1 application notes, or STEVAL-ISA153V1 alternative evaluation boards, this page provides verified topology details, measured efficiency curves, EMI compliance status (EN55022 Class B), burst-mode operation behavior, and VIPER38LE protection feature mapping to hardware implementation.

Technical Context

The board implements a current-mode controlled, fixed-frequency (60 kHz) isolated flyback topology with frequency jittering to reduce EMI peaks. It uses transformer-coupled optocoupler feedback for precise 12 V output regulation under line and load variation.

VIPER38LE integration enables single-chip primary-side control with built-in 800 V MOSFET, dual-level overcurrent protection (OCP), output overvoltage protection (OVP), short-circuit protection, and thermal shutdown with hysteresis - all directly implemented on the board without external components.

Key Specifications

Availability

STEVAL-ISA153V1 is available at Aetrix Electronics and suitable for industrial power supply prototyping, smart home AC/DC adapter development, and IoT gateway auxiliary power design requiring stable component supply and reference-grade validation data.

Supply support for STEVAL-ISA153V1 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, designing and manufacturing microcontrollers, power ICs, sensors, and analog devices for industrial, automotive, and consumer markets.

This board belongs to ST's STEVAL (ST Evaluation) series, developed to accelerate adoption of VIPerPlus offline controllers by providing fully tested, documented, and compliant reference designs for cost-sensitive, space-constrained AC/DC conversion.

FAQ

What is the maximum continuous output power of STEVAL-ISA153V1?

The board delivers 15 W continuously at 12 V/1.25 A under full-load conditions with 230 VAC input and ambient temperature ≤40 °C. Peak capability reaches 20 W (12 V/1.65 A) for up to 3 seconds, enabled by VIPER38LE's adjustable Extra Power Timer (EPT) circuitry.

Does STEVAL-ISA153V1 meet international EMI standards?

Yes - it complies with EN55022 Class B conducted and radiated emission limits when tested per standard 3 m measurement setup. Layout, transformer shielding, and frequency jittering are integral to achieving this result without added filtering components.

Can the output voltage be adjusted to 5 V or 24 V?

No - the board is fixed at 12 V output. Output voltage is set by the TL431-based feedback divider and optocoupler CTR ratio; changing it requires redesigning the feedback network, transformer turns ratio, and verifying VIPER38LE bias winding operation and protection thresholds.

Is STEVAL-ISA153V1 RoHS compliant and lead-free?

Yes - the board conforms to RoHS Directive 2011/65/EU. All components, including the VIPER38LE IC, PCB finish, solder mask, and passive parts, are lead-free and halogen-free as confirmed in ST's official product declaration (DocID026381 Rev 1).