FTM Board Club
43W high power factor flyback converter with constant voltage output based on ICL8800

The REF_ICL8800_LED_43W is a 43W reference design featuring Infineon’s high power factor flyback controller ICL8800.

The board is a constant voltage (CV) secondary-side regulated (SSR) system and is intended to be used with a constant current (CC) converter for LED lighting applications.

Two-stage topologies are growing because of the convenient scalability of power on the primary side and the features on the secondary side. REF_ICL8800_LED_43W is designed as plug-and-play solution and can be combined with secondary-side DC/DC boards.

With its benchmarking performance in power factor correction and total harmonic distortion at full-load and low-load conditions, ICL8800 enables window drivers and platform designs.  Furthermore, the IC combines optimum efficiency and low EMI without compromising light quality.

Being the cost-optimized, basic-featured variant of the ICL88xx family, ICL8800 is the perfect fit for on-off drivers and dimming down to 5 percent.

As a default setup, the reference design board is assembled with a start-up circuit based on a depletion-mode MOSFET BSS126I on a very small adapter board. This setup offers the lowest standby losses. If low standby consumption is not necessary, the start-up circuit can be changed to a resistive start-up.

This reference design is provided with two regulation circuits. Both circuits are designed as plug-and-play solutions, but at least one has to be connected to the main board.

The two boards shall show the trade-off between cost; here the TL431 board offers a low-cost solution, and standby performance, while the op-amp board shows an overall 30mW better performance.

  • Constant voltage (CV) secondary-side regulated (SSR) reference design for LED lighting applications
  • Power factor (PF) > 0.9 and THD < 10% across a wide load range (AC input up to 277Vrms)
  • Maximum AC input voltage 90 – 305Vrms
  • Critical conduction mode and quasi-resonant mode with smart valley hopping