Handling of battery loss event

In some examples, a controller circuit comprises: a voltage subtractor circuit having a subtractor output and first and second subtractor inputs, in which the first subtractor input is adapted to be coupled to a first current terminal of a transistor, the second subtractor input is adapted to be coupled to a second current terminal of the transistor; a gate control circuit having a gate control input and a gate control output, the gate control input coupled to the subtractor output, the gate control output adapted to be coupled to a gate of the transistor; and a discharge circuit having a discharge circuit input and a discharge circuit output, the discharge circuit input coupled to the gate control circuit, the discharge circuit output adapted to be coupled to the first current terminal of the transistor.