STMicroelectronics EVAL-STCH03-45W

Overview

EVAL-STCH03-45W from STMicroelectronics is an evaluation board implementing a 45 W, 12 V isolated AC-DC power supply using a quasi-resonant flyback topology with STCH03 primary-side controller and SRK1000B adaptive synchronous rectification IC. It delivers 3.75 A continuous output, achieves >89% efficiency at 230 VAC full load, and maintains <40 mW standby power.

For engineers reviewing the EVAL-STCH03-45W datasheet, EVAL-STCH03-45W pinout, EVAL-STCH03-45W application, or EVAL-STCH03-45W equivalent, this board serves as a validated reference design for compact, high-efficiency offline SMPS targeting industrial control, IoT gateways, and smart home power supplies requiring EN60065 safety and EN55022 Class B EMI compliance.

Technical Context

The board implements a primary-side regulated QR flyback converter with optocoupler feedback for precise 12 V voltage regulation and primary-side sensing for constant-current behavior. Control is handled by the STCH03 IC, which integrates active burst-mode operation and valley-switching for high light-load efficiency and low EMI.

Secondary-side synchronous rectification uses the SRK1000B to drive the STL90N10F7 MOSFET, dynamically adjusting gate timing based on drain voltage zero-crossing detection. Protection features include auto-restart OVP, UVP, OPP, and SCP - all implemented via hardware monitoring circuits independent of firmware.

Key Specifications

Availability

EVAL-STCH03-45W is available at Aetrix Electronics and suitable for industrial control power modules, smart home hub power supplies, and IoT edge node AC-DC conversion requiring stable component supply, rapid prototyping validation, and regulatory-compliant reference designs.

Supply support for EVAL-STCH03-45W 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, analog ICs, power management devices, and discrete components for automotive, industrial, and consumer markets.

This evaluation board belongs to ST's STCH03-based QR flyback reference design portfolio, engineered to accelerate development of compact, high-efficiency, safety-certified offline power supplies for cost-sensitive, space-constrained applications.

FAQ

What is the primary topology and control architecture used on EVAL-STCH03-45W?

The board implements a quasi-resonant (QR) flyback converter with primary-side regulation using the STCH03 controller. Voltage regulation is achieved via optocoupler feedback, while constant-current behavior is enforced through primary-side sensing. The SRK1000B drives synchronous rectification on the secondary side using adaptive zero-voltage switching detection.

Does EVAL-STCH03-45W support automatic restart after fault conditions?

Yes - the board incorporates hardware-based protection circuits for overvoltage, undervoltage, overpower, and short-circuit events, all configured for auto-restart recovery. No firmware or external intervention is required to resume operation after fault clearance, ensuring robust field reliability.

Can EVAL-STCH03-45W be modified for different output voltages?

Yes - output voltage can be adjusted by changing the optocoupler feedback resistor divider on the secondary side. The STCH03 controller supports adjustable V_OUT within its regulation range; however, re-tuning of transformer turns ratio, MOSFET ratings, and rectifier selection is required for outputs significantly outside 12 V.

What certifications does EVAL-STCH03-45W meet out-of-the-box?

The board complies with EN60065 for safety (audio/video equipment) and EN55022 Class B for conducted and radiated emissions. These certifications apply to the published schematic and bill-of-materials; final system-level certification requires integration into the end-product enclosure and layout verification.