Patent ID: 6952103

Claim:
A circuit for monitoring resistance between the terminals of a battery and a first reference potential, said circuit comprising: first and second inputs each of which is connectable to one of the terminals of the battery; a voltage divider comprising first and second measurement resistors and having first and second external connections, and a central connection intermediate said first and second resistors, which central connection is connectable to the first reference potential; first and second switches, each of which is arranged in series in a connection between one of the external connections of the voltage divider and one of the inputs; and a measuring instrument, connected to the external connections of the voltage divider, for supplying a monitoring signal which is representative of a voltage between the external connections; wherein, the measuring instrument is a differential amplifier; the differential amplifier is connected to a second reference potential as a supply potential; and a test voltage source is provided having two terminals, one terminal being connected to a point on the circuit which supplies the second reference potential, and the other terminal being connected to one of the external connections of the voltage divider via a third switch.