A simple design and implementation of LED director with solar-power

In this paper, a LED director based on solar-power is developed for education purpose. The solar energy is converted to fixed output voltage to charge battery and drive LED matrix. A boost converter based on PWM controller AIC1630, is used to step up solar voltage. The sign pattern of LED is set and controlled by chip EM78M447SB. Two charging modes, including constant current mode and fixed voltage mode, are applied to charge of battery. Therefore, a shorter charging time and good life-time is reachable. The LED director is useful and convenient by experiment.