An electrical circuit for detecting circuit defects and/or for preventing overvoltages in controllers. The electrical circuit including a power controller circuit, encompassing a first transistor, a control loop including an operation amplifier and a first reference voltage source, and feedback resistors, and an overvoltage suppression circuit, encompassing a second transistor, a control loop including an operation amplifier and a reference voltage source, and feedback resistors, the power controller circuit being provided to make a voltage available for the overvoltage suppression circuit and the overvoltage suppression circuit being provided to make a protected voltage available.