For the advantages of high efficiency, good optical performance, long lifetime, environmentally friendly, insensitive to vibration, the high-brightness light-emitting diode is a promising new generation of green lighting source. The lifetime of the LED driver is the bottleneck of the whole system, which limits the LED luminaries' lifetime. An LED with biased square current driver was proposed. The method can decrease the power ripple in the bus capacitor. At the same voltage ripple, the volume of the bus capacitor decreases to 55.8%. So film capacitor can be adopted to replace electrolytic capacitor.