Lighting circuit and luminaire and a method of controlling a lighting circuit

摘要

According to one embodiment, a lighting circuit includes a high potential input terminal, a low potential input terminal, a high potential output terminal, a low potential output terminal, first and second switching elements, first and second rectifying elements, an inductor and a control circuit. The first switching element has one end connected to the high potential input terminal. The first rectifying element is connected between one other end of the first switching element and the low potential input terminal. The inductor has one end connected to the one other end of the first switching element. The second switching element is connected between one other end of the inductor and the low potential input terminal. The second rectifying element is connected between the one other end of the inductor and the high potential output terminal. The control circuit turns on or off the first and second switching elements.

主权项

1. A lighting circuit comprising:
a high potential input terminal connected to one end of an external power supply; a low potential input terminal connected to one other end of the external power supply; a high potential output terminal connected to one end of an illumination load; a low potential output terminal connected to one other end of the illumination load; a first switching element having one end connected to the high potential input terminal; a first rectifying element connected between one other end of the first switching element and the low potential input terminal, a forward direction of the first rectifying element being a direction from the low potential input terminal to the first switching element; an inductor having one end connected to the one other end of the first switching element; a second switching element connected between one other end of the inductor and the low potential input terminal; a second rectifying element connected between the one other end of the inductor and the high potential output terminal, a forward direction of the second rectifying element being a direction from the inductor to the high potential output terminal; and a control circuit configured to turn off the second switching element at a time earlier by at least a first time than a time when the control circuit turns the first switching element from on to off.