Patent ID: 6489778
Filing Date: 2002-12-03
Classification: H03K

Abstract:
A method of recognizing a fault current in a control unit having an output connected to a load which can be switched by a switch such that the load is enabled or disabled, wherein the switch is located in the control unit along a path of current flow through the control unit and into the load, the method including steps of controlling the switch by the control unit, detecting within the control unit a current flowing into the control unit via the control unit's output, producing a fault signal depending on the fault current detected in the control unit, and wherein the detecting step is accomplished by use of a transistor circuit located within the control unit and comprising a transistor and a voltage divider establishing a voltage at a terminal of the transistor, the switch comprises a driver, the voltage divider is connected between terminals of the driver, and a further terminal of the transistor produces the fault signal and is available for use via a processor for control of the driver.