Patent ID: 11951919
Assignee: YAZAKI CORPORATION
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC B  H | IPC B  H

Claim 2:
3. An in-vehicle power supply system configured to supply power of a power supply on a vehicle side to an in-vehicle device serving as a load on a vehicle, the in-vehicle power supply system comprising:
a main battery configured to charge and discharge the power of the power supply;
an upper power supply unit configured to supply the power of the power supply to the main battery;
a first power supply line allocated to conduct the power of the power supply of a first voltage;
a second power supply line allocated to conduct the power of the power supply of a second voltage lower than the first voltage;
a step-down conversion unit configured to step down a voltage of the first power supply line to supply the power of the power supply to the second power supply line; and
a dark current supply circuit connected in parallel with the step-down conversion unit,
wherein the upper power supply unit, the main battery, and an input of the step-down conversion unit are connected to the first power supply line,

wherein an output of the step-down conversion unit is connected to the second power supply line, and
wherein the dark current supply circuit is configured to supply the power of the power supply generated by stepping down a voltage of the first power supply line to the second power supply line as a dark current in a case in which an ignition of the vehicle is OFF.