LED LIGHTING APPARATUS

摘要

An LED lighting apparatus includes a DC power source VIN, a series circuit connected to both ends of the DC power source and including an LED, an inductor L1, a switching element Q1, and a current detecting resistor R1, a regenerative diode D1 connected in parallel with a series circuit of the LED and inductor, a capacitor C2 to be charged and discharged according to a differential current between a current passing when the switching element is ON and a predetermined constant current, and a PWM control circuit 11 that carries out ON/OFF control of the switching element and PWM control based on a voltage of the capacitor to keep a current average value in each ON period of the switching element constant.

主权项

1. An LED lighting apparatus comprising:
a DC power source; a series circuit connected to both ends of the DC power source and including an LED, an inductor, a switching element, and a current detecting resistor; a regenerative diode connected in parallel with a series circuit of the LED and inductor; a capacitor for charging and discharging according to a differential current between a current passing through the switching element when the switching element is ON and a predetermined constant current; and a PWM control circuit that carrying out ON/OFF control of the switching element and PWM control based on a voltage of the capacitor to keep a current average value in each ON period of the switching element constant.