Semiconductor integrated circuit

A semiconductor integrated circuit for driving an inductive load, the semiconductor integrated circuit comprising:

• a semiconductor power switch element configured to drive the inductive load;
• a load current sensing circuit configured to sense a load current of the inductive load;
• a logic circuit configured to output a logic signal responsive to the load current sensing circuit sensing a drop in the load current while the semiconductor power switch element is in a turn-on state;
• a gate voltage pull-down circuit configured to pull down a gate voltage of the semiconductor power switch element upon receiving the logic signal;
• a clamp diode disposed between a gate of the semiconductor power switch element and a high-potential terminal connected to the inductive load;
• and
• a clamp withstand voltage drop circuit configured to switch a first withstand voltage of the clamp diode to a second withstand voltage upon receiving the logic signal, the second withstand voltage being lower than the first withstand voltage,
• wherein the load current sensing circuit includes
• a current sensing switch element that performs current division to obtain a current proportional to the load current,
• a current sensing resistor that converts the current obtained by the current sensing switch element into a voltage, to thereby output a sensed signal, and
• a hysteresis comparator that compares the sensed signal with a reference voltage and outputs a low current sensing signal when the sensed signal is lower than the reference voltage, and
• wherein the logic circuit outputs the logic signal upon receiving an input signal that turns on the semiconductor power switch element and the low current sensing signal.

A semiconductor integrated circuit for driving an inductive load, the semiconductor integrated circuit comprising:

• a semiconductor power switch element configured to drive the inductive load;
• a load current sensing circuit configured to sense a load current of the inductive load;
• a logic circuit configured to output a logic signal responsive to the load current sensing circuit sensing a drop in the load current while the semiconductor power switch element is in a turn-on state;
• a gate voltage pull-down circuit configured to pull down a gate voltage of the semiconductor power switch element upon receiving the logic signal;
• a clamp diode disposed between a gate of the semiconductor power switch element and a high-potential terminal connected to the inductive load;
• and
• a clamp withstand voltage drop circuit configured to switch a first withstand voltage of the clamp diode to a second withstand voltage upon receiving the logic signal, the second withstand voltage being lower than the first withstand voltage, wherein
• the clamp diode includes a plurality of diodes connected in series, and
• the clamp withstand voltage drop circuit includes a short-circuit switch element that is connected in parallel to a part of the plurality of diodes and that turns on upon receiving the logic signal.