POWER CIRCUIT, IN-VEHICLE DEVICE, AND POWER SUPPLY METHOD

摘要

It is detected by a first power reducing sensor (6) and a second power reducing sensor (7) that an input voltage of a linear regulator (2) is reduced to be close to the lower operation limit of the linear regulator (2). A capacitor series/parallel switching unit (5) switches switches (SW1, SW2, SW3, SW4, SW6, SW7) and a power ON/OFF switching unit (4) to switch the connection of capacitors (C1, C2) between parallel connection and series connection.When the capacitors (C1, C2) are connected in parallel, the capacitors (C1, C2) are charged from an in-vehicle battery (3) and the linear regulator (2) is operated. When the capacitors (C1, C2) are connected in series, electric charges of the capacitors (C1, C2) are discharged to allow the linear regulator (2) to be operated. Then, the connection is alternately switched between parallel connection and series connection.