STMicroelectronics EVAL-PSR01B-35W

Overview

EVAL-PSR01B-35W from STMicroelectronics is a 35 W isolated flyback evaluation board implementing primary-side regulation (PSR) using the HVLED001B quasi-resonant controller and STF10LN80K5 800 V superjunction MOSFET. It delivers 48 V / 730 mA output from 90–265 V_AC, achieves >90% average full-load efficiency, <150 mW no-load power, and complies with EN60065 safety and EN55022 conducted emissions standards - designed for LED driver and auxiliary supply applications in lighting systems.

For engineers reviewing the EVAL-PSR01B-35W datasheet, EVAL-PSR01B-35W pinout, EVAL-PSR01B-35W application, or EVAL-PSR01B-35W equivalent, this board enables rapid validation of HVLED001B-based PSR flyback topologies under wide-input AC conditions, with focus on power factor correction, light-load efficiency optimization via frequency fold-back, and robust short-circuit auto-restart behavior.

Technical Context

The board implements a primary-side regulated quasi-resonant flyback converter with zero-voltage switching (ZVS) enabled by the HVLED001B's ZCD pin sensing and adaptive TOFF control. Input rectification uses a 2KBP08M bridge, while output rectification employs STPS4S200S Schottky diode and filtering via 22 µF/50 V and 22 µF/50 V parallel capacitors.

HVLED001B provides integrated protections including overvoltage lockout (via VRECT monitoring), cycle-by-cycle current limiting (CS pin), and short-circuit/auto-restart (OPTO feedback path). The STF10LN80K5 MOSFET operates at up to 800 V with R_DS(on) = 0.55 Ω and is mounted on heatsink HS1 with 21°C/W thermal resistance.

Key Specifications

Availability

EVAL-PSR01B-35W is available at Aetrix Electronics and suitable for LED driver development, industrial auxiliary power supply design, and smart lighting control system prototyping requiring stable component supply and pre-validated safety/EMI performance.

Supply support for EVAL-PSR01B-35W 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 devices, and discrete components for automotive, industrial, and consumer markets.

This board belongs to ST's LED lighting evaluation platform family, developed to accelerate adoption of high-efficiency, PSR-based AC/DC converters targeting cost-sensitive, safety-compliant lighting applications.

FAQ

What is the purpose of the OPTO connector (J1) on EVAL-PSR01B-35W?

The OPTO connector (J1) provides access to the optocoupler feedback path used by the HVLED001B for primary-side regulation. It allows engineers to inject external feedback signals, modify compensation networks, or interface with custom secondary-side controllers - enabling flexibility in closed-loop tuning and system integration beyond the default 48 V output configuration.

Can EVAL-PSR01B-35W operate with input voltages below 90 V_AC or above 265 V_AC?

No - the board is validated only for 90–265 V_AC input per its safety certification and component ratings. Operation outside this range risks violating EN60065 insulation requirements, exceeding the 800 V rating of STF10LN80K5, or triggering HVLED001B's overvoltage/undervoltage protection, resulting in shutdown or unreliable regulation.

How does the frequency fold-back feature improve light-load performance?

The HVLED001B reduces switching frequency proportionally as load decreases, lowering core losses and conduction losses in the transformer and MOSFET. This maintains >85% efficiency down to 10% load while simultaneously reducing output voltage ripple - critical for noise-sensitive LED dimming circuits and low-power auxiliary rails.

Is the EVAL-PSR01B-35W RoHS and REACH compliant?

Yes - all components on the board meet RoHS Directive 2011/65/EU and REACH Regulation (EC) No. 1907/2006, as confirmed by STMicroelectronics' material declarations and DB3733 Rev 1 documentation dated October 2018. PCB finish is lead-free immersion silver, and no SVHC substances above threshold are present.