STMicroelectronics STEVAL-ILL017V1

Overview

STEVAL-ILL017V1 from STMicroelectronics is a 2 W non-isolated offline constant current LED driver demonstration board based on the VIPer17 high-voltage PWM controller IC. It accepts 176–264 VAC input, delivers 500 mA constant current at 7 VDC output, and features overtemperature, LED open/short-circuit, and adjustable overvoltage protection for driving two series-connected LEDs in lighting adapters and auxiliary supplies.

For engineers reviewing the STEVAL-ILL017V1 datasheet, STEVAL-ILL017V1 application, STEVAL-ILL017V1 schematic, or STEVAL-ILL017V1 equivalent, this board serves as a validated reference design for low-power AC/DC LED drivers requiring EMI-compliant jittered-frequency operation, <50 mW standby power, and robust fault recovery in consumer and industrial auxiliary power applications.

Technical Context

The board implements a flyback-derived, non-isolated constant-current topology using the VIPer17's integrated 800 V avalanche-rugged power section and internal PWM controller. It operates in burst mode at light load to achieve <50 mW standby power and uses frequency jittering (60 kHz for L-type, 115 kHz for H-type) to reduce conducted EMI without increasing filter component count.

Current regulation relies on a single sense resistor plus two precision (±1%) resistor bridges, achieving ±5% output current accuracy. Protection functions-including hysteretic thermal shutdown, auto-restart after fault clearance, brown-out detection, and on-board soft-start-are fully implemented using VIPer17's embedded features and discrete support circuitry.

Key Specifications

Availability

STEVAL-ILL017V1 is available at Aetrix Electronics and suitable for LED lighting adapters, auxiliary power supplies for LCD/PDP TVs and monitors, and low-power SMPS in set-top boxes and white goods requiring stable component supply and rapid design validation.

Supply support for STEVAL-ILL017V1 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 devices, and silicon solutions for industrial, automotive, and consumer markets.

This board belongs to ST's STEVAL (ST Evaluation) family-engineered to accelerate prototyping and qualification of ST's power conversion ICs, specifically targeting cost-sensitive, safety-certifiable offline LED driver and auxiliary supply applications.

FAQ

Is STEVAL-ILL017V1 certified for safety standards such as IEC 62368-1 or UL 62368-1?

No safety certification is claimed for STEVAL-ILL017V1 in its documentation. It is a demonstration board intended for lab evaluation only-not for end-product certification. Users must perform full safety testing on their final design, including creepage/clearance verification, insulation coordination, and thermal analysis per applicable regional standards.

Can STEVAL-ILL017V1 drive more than two LEDs in series?

No-it is designed specifically for a 7 VDC output at 500 mA, matching the forward voltage drop of two typical white LEDs (~3.5 V each). Increasing the LED count would exceed the output voltage capability and violate the board's operating point; redesign of transformer turns ratio, feedback network, and current sense is required.

What is the role of the TSM103W op-amp on this board?

The TSM103W dual op-amp provides precision current sensing and feedback conditioning: one section compares the LED current sense signal against a stable reference to regulate output, while the second implements overvoltage protection by monitoring the output rail and disabling the VIPer17 if threshold is exceeded.

Does STEVAL-ILL017V1 support dimming functionality?

No native dimming interface is provided. The board lacks PWM dimming input, analog dimming pin, or digital control bus. Dimming would require external modification-such as injecting a variable bias into the current sense node or modulating the FB pin-neither of which is supported by default layout or firmware.