| 摘要 |
The invention relates to a circuit arrangement to which the electrical system power supply voltage (VBAT) of a motor vehicle is applied. In order to momentarily maintain at least one internal operating direct current voltage (Vcc1, ) in the event of an interruption in the vehicle electrical system power supply voltage (VBAT), said circuit arrangement comprises a power reserve store (3) to which a charging voltage is applied during normal operation. This charging voltage is greater than the at least one internal operating direct current voltage (VRES). In the event of an interruption in the vehicle electrical system power supply, said power reserve store releases a reserve voltage (VRES) by means of which the operation of at least some of the electronic circuits can be maintained for a limited period of time. The circuit arrangement also comprises at least one step-down controller (7, ), which steps down the applied input direct current voltage (VZP) to the level of the at least one internal operating direct current voltage (Vcc1, ). During normal operation, the power supply direct current voltage is applied directly as charging voltage to the power reserve store and as input direct current voltage to the step-down controller. |
