STMicroelectronics EVLHV101SSR50W

Overview

EVLHV101SSR50W from STMicroelectronics is a 50 W, 60 V / 833 mA isolated AC-DC evaluation board based on the HVLED101 quasi-resonant high-power-factor flyback controller with secondary-side regulation. It delivers >91% average efficiency across 25–100% load at 115/230 VAC input, features frequency foldback with valley locking for noise-free operation, and includes open-load voltage limiting (<65 V), short-circuit auto-restart, and NTC-based MOSFET overtemperature protection. It serves as a reference design for dimmable/non-dimmable offline LED drivers.

For engineers reviewing the EVLHV101SSR50W datasheet, EVLHV101SSR50W pinout, EVLHV101SSR50W application, or EVLHV101SSR50W equivalent, key selection criteria include its 60 V regulated output, 91.1–91.2% 4-point average efficiency, EN60065 safety compliance, EN55022 conducted EMI performance, and integrated protections for overvoltage, undervoltage, short-circuit, and thermal fault conditions.

Technical Context

This board implements a quasi-resonant flyback topology using the HVLED101 controller (U1), which integrates frequency foldback and valley-locking detection to minimize switching losses and acoustic noise. The secondary-side regulation loop employs U5 (TL432AIL3T) and U4 (SFH617-A2 optocoupler) for precise 60 V output control independent of line and load variations.

Input stage includes GBU406 bridge rectifier (D1), VDR-320V varistors (R1/R2), and X2/Y2 safety capacitors; power stage uses STF14N80K5 MOSFET (Q1) and PQ26-320 µH custom transformer (T1). Protection functions are implemented via dedicated pins on HVLED101 - ZCD for zero-current detection, FAULT for latch-off, THD for harmonic monitoring, and CS for current sensing.

Key Specifications

Availability

EVLHV101SSR50W is available at Aetrix Electronics and suitable for LED driver development, industrial lighting prototyping, and AC-DC power supply qualification requiring stable component supply, pre-validated safety compliance, and documented efficiency performance across universal input.

Supply support for EVLHV101SSR50W 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 discrete components for automotive, industrial, and consumer markets.

The EVLHV101SSR50W belongs to ST's LED lighting evaluation platform series, specifically engineered to demonstrate high-efficiency, high-power-factor, low-THD offline LED drivers using their proprietary HVLED101 controller architecture.

FAQ

What is the primary function of the EVLHV101SSR50W evaluation board?

The EVLHV101SSR50W is a fully assembled, tested demonstration board that implements a 50 W, 60 V isolated AC-DC power supply using ST's HVLED101 quasi-resonant flyback controller. Its purpose is to accelerate development of dimmable and non-dimmable LED drivers by providing validated schematics, layout, BOM, and performance data - not for end-product integration.

Can this board be used with leading-edge or trailing-edge dimmers?

Yes - the board accepts universal AC input (90–265 VAC) and maintains regulation under phase-cut dimmer waveforms. Its HVLED101 controller supports both leading-edge (TRIAC) and trailing-edge (electronic) dimmers when paired with appropriate front-end circuitry, as confirmed in ST Application Note AN4742.

Does the board include isolation and safety certification documentation?

Yes - the design complies with EN60065 for audio/video equipment safety and meets EN55022 Class B conducted emissions limits. Creepage/clearance distances, transformer insulation (reinforced), and Y-capacitor placement follow IEC 60950-1 and IEC 62368-1 requirements, and test reports are included in DB4867.

What is the role of the NTC thermistor (NTC1) on this board?

NTC1 (Vishay NTCALUG01A104FA) monitors the heatsink temperature near Q1 (STF14N80K5). Its resistance change is fed into the HVLED101's THD pin to trigger thermal shutdown if ambient temperature exceeds 60 °C, preventing MOSFET overstress and ensuring long-term reliability in enclosed luminaires.