High voltage freewheeling diodes in an extended capability LED driving application

The use of high power freewheeling diodes - Silicon Carbide Schottky and PiN rectifiers - in buck converter-based LED drivers is investigated. Applications biasing up to 60 LEDs at input voltages reaching 250V are developed for both diode types. Despite different switching behavior and dissipated power between freewheeling devices, experimental results show a significant converter driving capability extension and an efficiency of over 95% in all cases.