A circuit includes at least one coupling node configured to be coupled, via a cable, to a load to transmit a supply voltage thereto. The circuit includes test circuitry configured to sense at least one sensing signal indicative of a value of the cable impedance and/or of the cable voltage across the cable, to perform a comparison between the at least one sensing signal and at least one threshold indicative either of a threshold resistance value for the cable impedance or indicative of a threshold voltage value for the cable voltage, produce a comparison signal as a result of the comparison.