Patent ID: 9566920
Date: 2017-02-14
CPC Classifications: B60R,G06F

Claim:
1. A circuit arrangement for a motor vehicle, wherein the motor vehicle has a signal bus adapted to carry an activation signal, and an external voltage source, and wherein said circuit arrangement comprises: an external input voltage terminal adapted to be connected to the external voltage source; a signal bus terminal adapted to be connected to the signal bus; a bus transceiver that includes a voltage monitoring device, wherein said bus transceiver is connected to said external input voltage terminal and to said signal bus terminal and is adapted to receive the activation signal from the signal bus via said signal bus terminal; a controllable voltage supply arrangement that includes a controlled voltage output connected to a first monitoring input of said voltage monitoring device, a first voltage node and optionally an optional second voltage node, a supply voltage unit connected and adapted to supply a first voltage to said controlled voltage output via said first voltage node and optionally to supply an optional second voltage to said second voltage node if present, and a voltage control device that is connected to said first voltage node and to said controlled voltage output and that is adapted to control said first voltage supplied by said supply voltage unit via said first voltage node to said controlled voltage output; a first switch that is connected between said external input voltage terminal and said supply voltage unit, and that has a first switch control input thereof connected to a control output of said bus transceiver; and a control arrangement that includes a microcontroller, wherein said control arrangement is connected by a voltage supply line to said first voltage node or to said second voltage node and is connected by a control line to a control input of said voltage control device; wherein said microcontroller is adapted to execute an initialization process, and said control arrangement is adapted to control said voltage control device via said control line responsive to and dependent on a status of said initialization process as indicated by a status signal of said microcontroller.