Circuit device, lighting device, and vehicle using the same

A circuit device comprising:

• a plurality of first power supply connecting terminals that are connected to first one of a positive electrode and a negative electrode of a DC power supply;
• a second power supply connecting terminal that is connected to second one of the positive electrode and the negative electrode of the DC power supply;
• a load circuit;
• a plurality of protection circuits;
• and
• a reset circuit,
• wherein
• the load circuit includes,
• a first input terminal that is electrically connected to the plurality of first power supply connecting terminals in a state where the plurality of first power supply connecting terminals are connected in parallel to each other, and
• a second input terminal that is electrically connected to the second power supply connecting terminal,
• the plurality of protection circuits are respectively disposed between the plurality of first power supply connecting terminals and the first input terminal,
• each of the plurality of protection circuits includes
• a switching element that is connected between a corresponding first power supply connecting terminal of the plurality of first power supply connecting terminals and the first input terminal and is turned on when the DC power supply is connected with a normal polarity to the corresponding first power supply connecting terminal, and
• a rectifying element that is connected in parallel to the switching element between the corresponding first power supply connecting terminal and the first input terminal in a direction where a current having a normal polarity can flow, and
• the reset circuit is configured to periodically perform a reset operation of temporarily turning off the switching element in each of the plurality of protection circuits.