G5920-176-1Global Mixed-mode Technology Inc. G5920/G5921 Ultra Low-Dropout, Constant-Current White LED Bias Features General Description The G5920/G5921 is a high performance ultra lowdropout constant current bias supply for white LEDs. It can be used as an alternative to the simple ballast resistors in conventional parallel white LEDs applications. Each white LED bias current is matching to 0.6%. For dimming control, an enable input pin is controlled by processor GPIO output pulses for 32 level linear current. Using a low frequency PWM waveform to this enable input pin also controls the average LED current which is proportional to the PWM duty. The G5920/G5921 is suitable for single cell Li-ion battery power device that using low forward voltage white LEDs. The white LEDs can be powered d……