Abstract: An LED drive circuit that can increase the amount of light with a compact structure. This circuit includes series-connected LEDs, first and second DC power supplies connected in series so as to apply a forward bias to the LEDs, a coil that is series-connected with the LEDs and can accumulate energy from current generated by the DC power supplies, a rectifying element whose cathode is connected between the DC power supplies, a transfer switching element connected to the anode of the rectifying element, and a control apparatus for controlling the transfer switching element. A first closed circuit is formed by the LEDs, the DC power supplies, and the coil when the transfer switching element is switched on by the control apparatus, and a second closed circuit is formed by the LEDs, the second DC power supply, the coil, and the rectifying element when the transfer switching element is switched off.

Abstract: An LED drive circuit that can increase the amount of light with a compact structure. This circuit includes series-connected LEDs, first and second DC power supplies connected in series so as to apply a forward bias to the LEDs, a coil that is series-connected with the LEDs and can accumulate energy from current generated by the DC power supplies, a rectifying element whose cathode is connected between the DC power supplies, a transfer switching element connected to the anode of the rectifying element, and a control apparatus for controlling the transfer switching element. A first closed circuit is formed by the LEDs, the DC power supplies, and the coil when the transfer switching element is switched on by the control apparatus, and a second closed circuit is formed by the LEDs, the second DC power supply, the coil, and the rectifying element when the transfer switching element is switched off.