AN4129 Datasheet, PDF (1/39 Pages) Fairchild Semiconductor – Green Current Mode PWM Controller FAN7601

AN4129
Application note
STEVAL-ILL044V1: 9 W Triac dimmable, high power factor, isolated
LED driver based on the HVLED815PF (for US market)
By Thomas Stamm
Introduction
The STEVAL-ILL044V1 demonstration board showcases ST's new LED driver chip, the
HVLED815PF. It solves the problem of low-cost drive circuitry for LED replacements for 40
to 60 Watt incandescent or equivalent compact-fluorescent lamps.
The HVLED815PF is a new integrated power controller using primary-side control to
achieve LED current regulation within +/-5%. (It also has primary-side voltage regulation,
used here for open load protection.) The device incorporates an 800 V avalanche-rated FET
and fits in a standard SO-16 package. An internal startup circuit eliminates the need for
external rapid-start circuitry.
The PFC-flyback power converter operates in transition mode for highest efficiency and best
use of components. With the addition of a few extra components the HVLED815PF is made
to draw near-sinusoidal input current from the AC line. The circuit regulates LED current
over a wide range of line voltage and LED string voltage, and is dimmable with standard
Triac-based dimmers.
Figure 1. Image of top and bottom view
October 2012
Doc ID 023314 Rev 1
1/39
www.st.com