STMicroelectronics – Slim flyback converter board for LED drivers achieves very high efficiency


The STEVAL-ILL076V2 board from STMicroelectronics is an offline power converter based on a single stage isolated flyback topology, for use in a driver for a string of LEDs.

The board is notable for its slim form factor, the result of the innovative use of magnetic components. It also offers a high power factor of more than 0.95, matched by total harmonic distortion below 10%. The board provides isolation against over-voltages of up to 4kV.

Primary-side regulation of the output voltage, controlled by ST’s HVLED001A, helps to lower the system’s bill-of-materials cost, since it reduces the need for costly optocouplers. The precise operation of the HVLED001A controller and the innovative structure of the transformer make for highly accurate output-voltage regulation against load and line changes. At the same time, the STEVAL-ILL076V2 achieves very high efficiency at full load of higher than 92%.

The board accepts a universal mains input-voltage range of 90V to 264V AC, providing a power output of up to 18W at a voltage of 56V. When operating only from a European mains voltage, it can provide an output of up to 40W.


  • No-load power consumption
  • Short-circuit protection with auto-restart
  • Complies with EN55022 (B) limits for conducted EMI
  • Complies with EN60950 safety requirements


  • Isolated bus power supply for LED driver

Orderable Part Number: STEVAL-ILL076V2