A device for detecting a voltage drop between an anode connection and a cathode connection, comprising - a control capacitor (C K), of which the first electrode is connectable to the anode connection and the second electrode is connectable to the cathode connection; - a measuring device, which is designed to output a discharge signal (y) depending on a potential difference, which is detected between the anode connection and the cathode connection, and a first threshold value for the potential difference on a discharge control line; - a discharge circuit, which is connected to the discharge control line and is designed to discharge the control capacitor (C K) depending on the discharge signal (y); and - a control device, which is designed to detect the voltage drop by evaluating the state of charge of the control capacitor (C K), wherein the discharge circuit includes a second controlled switch, of which the control input is connected to the discharge control line and which is designed to connect the first electrode of the control capacitor (C K) with low impedance to the second electrode of the control capacitor (C K) when the discharge control line is disconnected from the cathode connection, and wherein the control input of the second controlled switch is connectable to the anode connection via a pull-up resistor (R P), characterized in that the measuring device includes a first controlled switch, of which the control input is connectable to the anode connection via a second voltage divider and which is designed to connect the discharge control line to the cathode connection with low impedance when the input potential applied at the control input exceeds the first threshold value, wherein the first controlled switch is designed to disconnect the discharge control line from the cathode connection when the input potential applied at the control input drops below the first threshold value. - a control capacitor (C K), of which the first electrode is connectable to the anode connection and the second electrode is connectable to the cathode connection; - a measuring device, which is designed to output a discharge signal (y) depending on a potential difference, which is detected between the anode connection and the cathode connection, and a first threshold value for the potential difference on a discharge control line; - a discharge circuit, which is connected to the discharge control line and is designed to discharge the control capacitor (C K) depending on the discharge signal (y); and - a control device, which is designed to detect the voltage drop by evaluating the state of charge of the control capacitor (C K), wherein the discharge circuit includes a second controlled switch, of which the control input is connected to the discharge control line and which is designed to connect the first electrode of the control capacitor (C K) with low impedance to the second electrode of the control capacitor (C K) when the discharge control line is disconnected from the cathode connection, and wherein the control input of the second controlled switch is connectable to the anode connection via a pull-up resistor (R P), characterized in that the measuring device includes a first controlled switch, of which the control input is connectable to the anode connection via a second voltage divider and which is designed to connect the discharge control line to the cathode connection with low impedance when the input potential applied at the control input exceeds the first threshold value, wherein the first controlled switch is designed to disconnect the discharge control line from the cathode connection when the input potential applied at the control input drops below the first threshold value.