by Valentin Kulikov @ edn.com
This article describes simple constant current driver module with fast PWM input that can be used for driving medium and high power LEDs. The module uses an integrated constant-current output, DC-DC buck converter with output current configurable from 0.1 to 0.5A. This article outlines the schematic, design guidelines, operation, and performance of the low cost LED driver.
A low-cost 0.5A 33V LED driver module with 90+% efficiency – [Link]