The invention relates to: Control circuit (1) for an electrical device (2), said control circuit (1) receiving as input a discrete electrical control signal (CMD), the control circuit (1) comprising a source (11) of voltage (±V) configured so as to supply the circuit according to a negative or positive voltage; a switch (12) normally closed in the absence of any discrete electrical control signal (CMD) and configured so as to isolate the electrical device from the voltage source as a function of the electrical control signal (CMD), said switch being connected between the voltage source and the electrical device (2); the switch (12) being sensitive to the discrete electrical control signal (CMD) for just one sense of voltage.