There is provide a current detection circuit including: a current detection unit that detects a control current flowing between a control terminal of a semiconductor element of voltage-controlled type having a current detection terminal, and a drive circuit; an overcurrent detection unit that detects an overcurrent in response to a sense current exceeding an overcurrent threshold value, the sense current flowing through the current detection terminal; and an adjustment unit that sets, based on a detection result of the current detection unit, the overcurrent threshold value in a transient period during turn on and turn off of the semiconductor element to be higher than the overcurrent threshold value in a period other than the transient period.

There is provide a current detection circuit including: a current detection unit that detects a control current flowing between a control terminal of a semiconductor element of voltage-controlled type having a current detection terminal, and a drive circuit; an overcurrent detection unit that detects an overcurrent in response to a sense current exceeding an overcurrent threshold value, the sense current flowing through the current detection terminal; and an adjustment unit that sets, based on a detection result of the current detection unit, the overcurrent threshold value in a transient period during turn on and turn off of the semiconductor element to be higher than the overcurrent threshold value in a period other than the transient period.

An integrated circuit includes a signal output circuit configured to output a timing signal indicating first and second timings of respectively switching first and second switching devices, first and second hold circuits respectively configured to receive first and second voltages corresponding to temperatures of the first and second switching devices, hold the first and second voltages for first and second time periods, and output the received first and second voltages in response to the first and second time periods having elapsed, and first and second control circuits respectively configured to control switching of the first and second switching devices with first and second driving capabilities corresponding to the temperatures of the first and second switching devices, based on the first and second voltages outputted from the first and second hold circuits and first and second driving signals for driving the first and second switching device.

A power conversion circuit for an uninterruptible power system, including an inductor, a first capacitor, a second capacitor, a first switch, a second switch, a third switch, a first diode, a second diode, and a third diode body, is provided. A terminal of the second switch is electrically coupled to the inductor through the first switch, and another terminal of the second switch is electrically coupled to a neutral wire and the third switch. An anode and a cathode of the first diode are electrically coupled to the first switch and a positive DC bus, respectively. A cathode and an anode of the second diode are electrically coupled to the first switch and the third switch, respectively. A cathode and an anode of the third diode are electrically coupled to the third switch and a negative DC bus, respectively. In addition, an uninterruptible power system using the same is provided.

A power conversion circuit for an uninterruptible power system, including an inductor, a first capacitor, a second capacitor, a first switch, a second switch, a third switch, a first diode, a second diode, and a third diode body, is provided. A terminal of the second switch is electrically coupled to the inductor through the first switch, and another terminal of the second switch is electrically coupled to a neutral wire and the third switch. An anode and a cathode of the first diode are electrically coupled to the first switch and a positive DC bus, respectively. A cathode and an anode of the second diode are electrically coupled to the first switch and the third switch, respectively. A cathode and an anode of the third diode are electrically coupled to the third switch and a negative DC bus, respectively. In addition, an uninterruptible power system using the same is provided.

A power semiconductor device of the present disclosure includes: a first switching element; a second switching element connected in parallel to the first switching element, and having a higher short circuit capability than the first switching element; drive circuits to drive the first switching element and the second switching element; and determination circuits to compare a target current as a sum of a current flowing through the first switching element and a current flowing through the second switching element to a first threshold and a second threshold greater than the first threshold. The drive circuits switch off the first switching element when the determination circuits determine that the target current is equal to or greater than the first threshold, and switch off the second switching element when the determination circuits determine that the target current is equal to or greater than the second threshold.

A power semiconductor device of the present disclosure includes: a first switching element; a second switching element connected in parallel to the first switching element, and having a higher short circuit capability than the first switching element; drive circuits to drive the first switching element and the second switching element; and determination circuits to compare a target current as a sum of a current flowing through the first switching element and a current flowing through the second switching element to a first threshold and a second threshold greater than the first threshold. The drive circuits switch off the first switching element when the determination circuits determine that the target current is equal to or greater than the first threshold, and switch off the second switching element when the determination circuits determine that the target current is equal to or greater than the second threshold.

A control circuit for a switch device including a first switch element including a movable contact and a drive coil that controls the movable contact of the first switch element, the control circuit for returning the movable contact when the drive coil turns off the movable contact after the drive coil turns on the movable contact during supply of a source voltage from a power source, the control circuit includes a second switch element inserted between a rectifier circuit or a surge absorbing element and the first switch element, the second switch element being turned off when the supply of the source voltage is turned off. The rectifier circuit or the surge absorbing element is connected between the power source and the control circuit. The first switch element is turned off the movable contact is returned by turning off the second switch element to turn off the first switch element.

A control circuit for a switch device including a first switch element including a movable contact and a drive coil that controls the movable contact of the first switch element, the control circuit for returning the movable contact when the drive coil turns off the movable contact after the drive coil turns on the movable contact during supply of a source voltage from a power source, the control circuit includes a second switch element inserted between a rectifier circuit or a surge absorbing element and the first switch element, the second switch element being turned off when the supply of the source voltage is turned off. The rectifier circuit or the surge absorbing element is connected between the power source and the control circuit. The first switch element is turned off the movable contact is returned by turning off the second switch element to turn off the first switch element.

A current generation circuit includes a metal-oxide-semiconductor (MOS) transistor having a source terminal coupled to one line of a power supply line and a ground line, a voltage generation circuit configured to generate a first voltage corresponding to a resistance value of wiring between the one line and the source terminal, and a control circuit configured to cause the MOS transistor to generate a predetermined current based on the first voltage.