A nanosecond current pulse driver for light emitting diode

Abstract

High-intensity and short-duration light is necessary in many applications such as particle image velocimetry and light communication. Using nanosecond current pulse to drive LED or laser diode can generate such light to achieve higher efficiency. In nanosecond current pulse driver design, parasitic inductance effect is a big challenge. Parasitic inductance and voltage across it influence current change rate considerably. The proposed circuit uses source switching and current mirror topology to increase on/off speed of power MOSFET to achieve nanosecond current pulse. It reduces parasitic inductance effect and also overcomes the bandwidth limitation of conventional pulse current driver. Experiments show the proposed circuit provides 390mA current pulse with 40nswidth.