STMicroelectronics STEVAL-ISA118V1

Overview

STEVAL-ISA118V1 from STMicroelectronics is an offline flyback demonstration board implementing the VIPer16LN primary-switching controller, delivering up to 6 W over universal AC input (85–265 VAC) and up to 10 W at fixed 230 VAC. It features jittered fixed-frequency operation, no-auxiliary-winding capability, <30 mW standby power with auxiliary winding, and EN55022 Class B EMI pre-compliance.

For engineers reviewing the STEVAL-ISA118V1 datasheet, STEVAL-ISA118V1 pinout, STEVAL-ISA118V1 application, or STEVAL-ISA118V1 equivalent, this board serves as a validated reference for low-power AC/DC adapter, IoT wall plug, and industrial auxiliary supply designs requiring compact, RoHS-compliant, energy-efficient offline conversion.

Technical Context

The board implements a primary-side regulated flyback converter using the VIPer16LN - an integrated high-voltage 730 V MOSFET + PWM controller with built-in oscillator, current sensing, and protection circuitry. It supports both auxiliary-winding-based and auxiliary-winding-free feedback configurations via jumper selection.

Protection includes thermal shutdown with hysteresis, delayed overload response, and open-loop failure detection. Efficiency is validated per ENERGY STAR® active-mode test methodology, achieving >75% typical efficiency at full load across universal input range.

Key Specifications

Availability

STEVAL-ISA118V1 is available at Aetrix Electronics and suitable for low-power AC/DC adapter design, IoT edge node power supplies, and industrial auxiliary rail generation requiring stable component supply, rapid prototyping validation, and regulatory pre-compliance evidence.

Supply support for STEVAL-ISA118V1 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, analog chips, and silicon solutions for industrial, automotive, and consumer applications.

This board belongs to ST's STEVAL (ST Evaluation) series - purpose-built reference platforms that demonstrate real-world implementation of ST's power, interface, and control ICs with complete schematics, BOMs, layout files, and test reports.

FAQ

What is the primary controller IC used on the STEVAL-ISA118V1?

The board uses the VIPer16LN - a single-chip 730 V high-voltage PWM controller with integrated 16 A avalanche-rated MOSFET, designed specifically for low-power offline SMPS. It integrates startup circuitry, oscillator, current-sense amplifier, and protection logic, eliminating need for external bias winding in many configurations.

Can the STEVAL-ISA118V1 operate without an auxiliary winding?

Yes - the board supports both auxiliary-winding and no-auxiliary-winding operation via jumper configuration (J1/J2). In no-auxiliary mode, it relies on DCM-based primary-sensing feedback, reducing component count and board area while maintaining regulation accuracy within ±5% over line and load.

Does the board meet modern energy efficiency standards?

Yes - it achieves <30 mW standby consumption with auxiliary winding and is tested per ENERGY STAR® active-mode methodology. Its efficiency profile meets Level VI CoC requirements for ≤6 W output, and its EMI performance is pre-compliant to EN55022 Class B, reducing qualification risk for end equipment.

Is the STEVAL-ISA118V1 RoHS compliant and suitable for commercial deployment?

Yes - the board and all listed BOM components are RoHS compliant (per Doc ID 024064 Rev 1). It is intended for evaluation and reference use in commercial-grade power supply designs, including wall adapters, smart home sensors, and industrial control auxiliaries - not for safety-critical or automotive-grade applications unless requalified by the end user.