A device for driving a power supply start-up circuit for equipment fed with a power supply signal over a power supply line, the device including: - a logic unit for storing the operating state of said equipment, the logic unit being activatable by a start-up signal (VSTUP) over a start-up line reaching a start-up threshold, wherein said logic unit is configured to send an enable signal (ENAB) to the power supply start-up circuit, - a detector coupled to said start-up line, wherein the detector provides to the logic unit a signal indicating a drop in the signal over said start-up line below a drop threshold, the detector enabling the logic unit to continue operating in the presence of a failure of said power supply signal on said power supply line to store the operating state of said equipment upon occurrence of a failure of said power supply signal, wherein said detector and said logic unit co-operate in making the system capable of detecting and storing the information related to a faulty condition, and - a start-up circuit sensitive to said power supply signal on said power supply line, said start-up circuit activatable by said power supply signal on said power supply line as restored after a failure, to provide said start-up signal (VSTUP) reaching said start-up threshold upon said power supply signal being restored, characterized in that coupled with said start-up line, at least one of: - a capacitor to enable activation of said logic unit during build-up of said start-up signal (VSTUP), and - a Zener diode coupled with said start-up line to prevent said start-up line from reaching levels in excess of the limit values admitted for the circuits coupled therewith, and said start-up circuit includes an electronic switch with a control electrode driven by said power supply signal on said power supply line to charge said capacitor at a voltage corresponding to said start-up signal (VSTUP). - a logic unit for storing the operating state of said equipment, the logic unit being activatable by a start-up signal (VSTUP) over a start-up line reaching a start-up threshold, wherein said logic unit is configured to send an enable signal (ENAB) to the power supply start-up circuit, - a detector coupled to said start-up line, wherein the detector provides to the logic unit a signal indicating a drop in the signal over said start-up line below a drop threshold, the detector enabling the logic unit to continue operating in the presence of a failure of said power supply signal on said power supply line to store the operating state of said equipment upon occurrence of a failure of said power supply signal, wherein said detector and said logic unit co-operate in making the system capable of detecting and storing the information related to a faulty condition, and - a start-up circuit sensitive to said power supply signal on said power supply line, said start-up circuit activatable by said power supply signal on said power supply line as restored after a failure, to provide said start-up signal (VSTUP) reaching said start-up threshold upon said power supply signal being restored, - a capacitor to enable activation of said logic unit during build-up of said start-up signal (VSTUP), and - a Zener diode coupled with said start-up line to prevent said start-up line from reaching levels in excess of the limit values admitted for the circuits coupled therewith, and