Abstract: A semiconductor device is subjected to ON/OFF control by controlling a gate voltage according to a drive control signal. In a turn-on operation for charging a gate in response to transition of drive control signal from a first level to a second level, a drive signal is set to first level to discharge the gate at a first time after end of a Miller period of a gate voltage, thereby providing a voltage drop period in which gate voltage temporarily drops. At a second time, drive signal is again set to second level to start charging the gate.

Abstract: A semiconductor device includes a power switching element and a drive device to drive the power switching element. The drive device includes a voltage source, a switching element, a capacitor connected in parallel to the voltage source with the switching element being interposed, a switching element provided between the capacitor and a gate terminal of the power switching element, a first comparison device to output a result of comparison between a voltage of the capacitor and a reference value VQR, a second comparison device to output a result of comparison between a gate voltage of the power switching element and a reference value VR, and a short-circuit determination unit that makes determination as to a short circuit of the power switching element based on an output signal from the first comparison device and an output signal from the second comparison device.

Abstract: A semiconductor drive device includes a drive circuit that drives a semiconductor switching element, a passive element connected to a gate of the semiconductor switching element to prevent a gate current of the semiconductor switching element, a switching element connected in series to the passive element, a control circuit that controls the switching element, and a temperature detection circuit that detects a temperature of the semiconductor switching element. The control circuit controls the switching element such that when the temperature detected by the temperature detection circuit is high, the gate current is prevented more than when the temperature is low.

Abstract: A semiconductor device is subjected to ON/OFF control by controlling a gate voltage according to a drive control signal (Ssw). In a turn-on operation for charging a gate in response to transition of drive control signal (Ssw) from a first level (0) to a second level (1), a drive signal (Sdr) is set to first level (0) to discharge the gate at a first time (t1) after end of a Miller period (200) of a gate voltage (Vg), thereby providing a voltage drop period (210) in which gate voltage (Vg) temporarily drops. At a second time (t2), drive signal (Sdr) is again set to second level (1) to start charging the gate.

Abstract: A semiconductor device includes a power switching element and a drive device to drive the power switching element. The drive device includes a voltage source, a switching element, a capacitor connected in parallel to the voltage source with the switching element being interposed, a switching element provided between the capacitor and a gate terminal of the power switching element, a first comparison device to output a result of comparison between a voltage of the capacitor and a reference value VQR, a second comparison device to output a result of comparison between a gate voltage of the power switching element and a reference value VR, and a short-circuit determination unit that makes determination as to a short circuit of the power switching element based on an output signal from the first comparison device and an output signal from the second comparison device.

Abstract: A semiconductor drive device includes a drive circuit that drives a semiconductor switching element, a passive element connected to a gate of the semiconductor switching element to prevent a gate current of the semiconductor switching element, a switching element connected in series to the passive element, a control circuit that controls the switching element, and a temperature detection circuit that detects a temperature of the semiconductor switching element. The control circuit controls the switching element such that when the temperature detected by the temperature detection circuit is high, the gate current is prevented more than when the temperature is low.

Abstract: This temperature detection circuit includes: a temperature sensor having a resistance value that changes according to a change in temperature; an AC power supply that supplies AC power to the temperature sensor; a resonance circuit connected to the temperature sensor, the resonance circuit having an impedance that has an extreme value when AC power having a resonance frequency is supplied; and a voltage detection circuit that detects a voltage applied to any of a plurality of elements connected to the AC power supply. The resonance frequency in the resonance circuit and the frequency of the AC power are set to coincide with each other.

Abstract: An endoscope accessory case includes: a case body made up of a bottom portion and an impermeable trunk portion, the case body including an opening portion provided in a top face, and a fluid introduction port configured to introduce a fluid; and an impermeable lid, the lid including a contact portion configured to come into contact with the case body, and a bubble lead-out edge located at a position apart from an inner circumference of the case body and configured to lead out bubbles separated from endoscope accessories when the endoscope accessories held in the case body are agitated by being pushed by the fluid, the lid being configured to detachably cover the opening portion.

Abstract: An endoscope accessory case includes: a case body made up of a bottom portion and an impermeable trunk portion, the case body including an opening portion provided in a top face, and a fluid introduction port configured to introduce a fluid; and an impermeable lid, the lid including a contact portion configured to come into contact with the case body, and a bubble lead-out edge located at a position apart from an inner circumference of the case body and configured to lead out bubbles separated from endoscope accessories when the endoscope accessories held in the case body are agitated by being pushed by the fluid, the lid being configured to detachably cover the opening portion.