Removing the LED light strobe flicker by proper driver designs

摘要

Replacing traditional incandescent and fluorescent lights with more efficient, and longer-life LEDs is the trend in the lighting industry. However, since it is directly connected to AC line, like the traditional forerunners, there is a risk that 100Hz or 120Hz flicker could occur as a result of driving current ripple at the supply's output, which may make the consumers uncomfortable though most of the time human eyes are not able to notice them. LED and luminaire manufacturers are keen to get the problem solved, and they turned to the driver manufacturers because ultimately the driver determines whether flicker or not. This article investigates the cause of flicker, describes how it occurs to LEDs, and explains how engineers do trade-off between different solutions to solve the problems. Finally it offers a cost-effective and flexible way of implementing flicker-free LED lighting by utilizing ripple suppressor.