In-vehicle cut-off current supply device

A vehicle-mounted cut-off current supply device (10) is provided with: a transformer (20) having a first winding section (21) and a second winding section (22); a drive unit (12); and a capacitor (28). The drive unit (12) switches between a permitted state in which energization to the first winding unit (21) is permitted, and a released state in which the permitted state is released. The capacitor (28) is electrically connected to an intermediate conductive line between the second winding section (22) and the circuit breaker (6), and is capable of receiving power from the second winding section (22). The charging current is supplied to the capacitor (28) from the second winding section (22) side in response to the drive section (12) alternately repeating switching between the permitted state and the released state. The capacitor (28) is discharged in response to an ON operation of the switch (30), and the drive current flows to the current input unit (7). 车载用切断电流供给装置（10）具有：变压器（20），具有第一绕组部（21）和第二绕组部（22）；驱动部（12