STMicroelectronics STEVAL-ISA009V1

Overview

STEVAL-ISA009V1 from STMicroelectronics is a single-output offline AC/DC reference design board based on the VIPer53-E high-voltage converter IC, delivering 24 W at 12 V / 0.42 A from 90–264 VAC input, featuring current-mode control, optocoupler-based secondary-side regulation, and EN55022 Class B EMI compliance.

For engineers reviewing the STEVAL-ISA009V1 datasheet, STEVAL-ISA009V1 schematic, STEVAL-ISA009V1 application notes, or STEVAL-ISA009V1 bill of materials, this board serves as a validated starting point for designing compact, cost-effective 24 W SMPS solutions in industrial power supplies, auxiliary power units, and white goods control systems.

Technical Context

The board implements primary-side switching using the VIPer53-E integrated high-voltage MOSFET and controller, operating at a fixed 100 kHz switching frequency with adjustable current limit. Secondary-side feedback is closed via an H11A817A optocoupler driving the TL431 shunt regulator, enabling precise 12 V ±1% output regulation under line and load variation.

Protection features include cycle-by-cycle current limiting, output short-circuit and overload shutdown, thermal shutdown, and fuse-based overcurrent protection (0.5 A, 5×20 mm). Input filtering uses a KBP210GDI bridge rectifier and 30 mH common-mode choke, meeting Blue Angel environmental criteria and EN55022 Class B conducted/radiated EMI limits.

Key Specifications

Availability

STEVAL-ISA009V1 is available at Aetrix Electronics and suitable for industrial control panels, appliance mainboard auxiliary supplies, smart meter power stages, and IoT gateway power subsystems requiring stable component supply and proven reference design validation.

Supply support for STEVAL-ISA009V1 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, Switzerland, designing and manufacturing microcontrollers, power ICs, analog chips, and MEMS sensors for industrial, automotive, and consumer applications.

This board belongs to ST's STEVAL (ST Evaluation) series-reference designs intended to accelerate development of certified, production-ready power conversion and system control solutions.

FAQ

Is STEVAL-ISA009V1 still in active production?

No-STMicroelectronics has marked STEVAL-ISA009V1 as obsolete per its December 2007 data brief revision history. It remains available through authorized distributors and Aetrix Electronics for legacy design support, but no new silicon revisions or long-term supply commitments are offered.

Can this board be modified for 5 V or 15 V output?

Yes-output voltage is set by the TL431 + optocoupler feedback divider (R5 = 2.43 kΩ, R8 = 2.49 kΩ). Adjusting these resistors recalculates the reference ratio; redesign of output capacitor (C9), rectifier (D2), and possibly transformer turns ratio is required for stable regulation at 5 V or 15 V.

What is the role of the CVP32-002 transformer on this board?

The CVP32-002 is a custom-wound flyback transformer with 30 mH primary inductance and integrated auxiliary winding. It provides galvanic isolation, energy transfer, and auxiliary bias supply for the VIPer53-E Vdd pin-critical for startup and sustained operation without external bias circuitry.

Does STEVAL-ISA009V1 support PFC or synchronous rectification?

No-it uses passive input rectification (KBP210GDI) and a standard Schottky output rectifier (D2: 1N5821). No active PFC stage or synchronous rectifier driver is included; the design prioritizes simplicity and cost over high-efficiency or power factor correction.