Overcurrent protection circuit

An overcurrent protection circuit that is applied to an electronic circuit including at least one series circuit of an upper switching element and a lower switching element, the overcurrent protection circuit comprising:

• an amplification circuit configured to amplify an inter-terminal voltage of a shunt resistor for through-current detection;
• an offset application circuit connected to an input terminal of the amplification circuit to allow the amplification circuit to provide an output with a predetermined offset voltage additionally applied thereto;
• a comparison circuit for through-current sensing that compares an output voltage from the amplification circuit with a predetermined first reference voltage higher than the offset voltage to output a through-current sensing signal when the output voltage from the amplification circuit is higher than the first reference voltage;
• a duration measurement circuit configured to measure a duration for which a through-current sensing signal is output from the comparison circuit for through-current sensing;
• and
• an amplification circuit failure determination circuit that compares the output voltage from the amplification circuit with a predetermined second reference voltage that is higher than zero and lower than the offset voltage to output an amplification circuit failure determination signal corresponding to a result of the comparison.