Power Supply Circuit and Illumination Apparatus

摘要

According to one embodiment, there is provided a power supply circuit including a power conversion unit, a current regulator, a controller, and a controller power supply. The power conversion unit converts an AC voltage with a controlled conduction angle into a different voltage. The current regulator includes a branch path electrically connected to the power supply path and switches between a first state in which a part of a current flowing through the power supply path flows to the branch path and a second state in which a current flowing to the branch path is lower than that of the first state. The controller switches the current regulator to the second state in at least a part of a conduction period of a detected conduction angle and switches the current regulator to the first state in a blocking period of the detected conduction angle.

主权项

1. A power supply circuit comprising:
a power conversion unit that converts an AC voltage with a controlled conduction angle, supplied through a power supply path, into a different voltage and supplies the converted voltage to a load; a current regulator that includes a branch path electrically connected to the power supply path and can switch between a first state in which a part of a current flowing through the power supply path flows to the branch path and a second state in which a current flowing to the branch path is lower than that of the first state; a controller that detects a conduction angle of the AC voltage and controls the switching of the current regulator between the first state and the second state based on the detected conduction angle; and a controller power supply that is electrically connected to the branch path, converts a voltage, supplied through the branch path, into a driving voltage corresponding to the controller, and supplies the driving voltage to the controller, the controller switching the current regulator to the second state in at least a part of a conduction period of the detected conduction angle and switching the current regulator to the first state in a blocking period of the detected conduction angle.