| 摘要 |
<p>PURPOSE: A light emitting diode (LED) lighting system is provided to control a dimming level variously by using a turn-off/turn-on operation of a wall switch without a separate wiring work and an additional composition. CONSTITUTION: A full wave rectifier (102) rectifies an alternating current (AC) power source which is inputted through a wall switch (98) into a direct current (DC) voltage. An LED lighting driver (80) generates a fixed current from the DC voltage which is rectified through the full wave rectifier and supplies to an LED lamp (99). The LED lighting driver provides a multi-level dimming according to a count value of turn-off/turn-on operation of a counter (96). The LED lighting driver includes an inductor (81), a circulating diode (82), a power metal oxide semiconductor field effect transistor (MOSFET) (83), and a switching controller (85). The switching controller controls the duty cycle of the power MOSFET according to the count value of the counter.</p> |
