LM3409HV-REF, LM3409HV MR16 Buck-Boost Reference Design for Non-Dimming/Dimming LED Applications

LM3409HV-REF, describes the design and shows practical test results of this LED-based MR16 designed to drive 3 LEDs in series from an AC input voltage of 11.5VAC rms generated by 50Hz magnetic transformers or Electronic transformers. Halogen MR16 bulbs do not flicker because the light emitted depends on the heat of the wire in the bulb. The heat changes more slowly compared with the change in current (50Hz) from the mains. The light emitted by LEDs changes instantly with the current. Therefore special measures need to be taken to avoid flickering. The solution is to create a system that has a power factor close to 1 to get the same behavior as the halogen bulb