Patent ID: 8493072

Claim:
An apparatus for detecting a short-circuit occurring between a signal line ( 120 ) and a ground line ( 130 ) of a lead wire ( 110 ), comprising: a circuit ( 140 ) having an output terminal ( 170 ), an input terminal ( 190 ) and ground, the ground ( 180 ) of the circuit ( 140 ) being connected to one end of the ground line ( 130 ), the other end of the ground line ( 130 ) being disconnected; a resistive element ( 150 ) having a first terminal connected to the output terminal ( 170 ) of the circuit ( 140 ) and a second terminal connected to one end of the signal line ( 120 ), the other end of the signal line ( 120 ) being disconnected; wherein the circuit ( 140 ) is configured to provide a first voltage via the output terminal ( 170 ) and obtain a second voltage via the input terminal ( 190 ), the input terminal ( 190 ) being connected to a joint ( 160 ) of the signal line ( 120 ) and the resistive element ( 150 ), to provide a third voltage via the output terminal ( 170 ) and obtain a fourth voltage via the input terminal ( 190 ), to derive an impedance of the lead wire ( 110 ) from the first voltage, the second voltage, the third voltage, the fourth voltage and an impedance of the resistive element ( 150 ), and to determine whether a short-circuit occurs or not, based on the derived impedance of the lead wire ( 110 ) and a predefined impedance.