A semiconductor device according to embodiments includes a normally-off transistor having a first electrode, a second electrode, and a first control electrode, a normally-on transistor having a third electrode electrically connected to the second electrode, a fourth electrode, and a second control electrode, a first element having a first end portion electrically connected to the first control electrode and a second end portion electrically connected to the first electrode, and the first element including a first capacitance component; and, a second element having a third end portion electrically connected to the first control electrode and the first end portion and a fourth end portion, and the second element including a second capacitance component, wherein, when a threshold voltage of the normally-off transistor is denoted by V.sub.th, a maximum rated gate voltage of the normally-off transistor is denoted by V.sub.g_max, a voltage of the fourth end portion is denoted by V.sub.g_on, the first capacitance component is denoted by C.sub.a, and the second capacitance component is denoted by C.sub.b, V.sub.th<(C.sub.b/(C.sub.a+C.sub.b))V.sub.g_on<V.sub.g_max.

An enhanced layout for a multiple-finger ESD protection device has several embodiments. In these embodiments, the base contacts of the NPN (or PNP) transistors utilized as voltage clamps in the multiple-finger NPN-based (or PNP-based) multiple-finger ESD protection device are disposed at opposite edges of the multiple-finger ESD protection device and oriented perpendicularly to the orientation of the fingers in the multiple-finger ESD protection device. Similarly, the body contacts of the NMOS (or PMOS) transistors utilized as voltage clamps in the multiple-finger NMOS-based (or PMOS-based) multiple-finger ESD protection device are disposed at opposite edges of the multiple-finger ESD protection device and oriented perpendicularly to the orientation of the fingers in the multiple-finger ESD protection device.

A semiconductor module including a semiconductor element which is bonded to a wiring pattern part and connects or disconnects two main electrode terminals to or from each other according to a drive signal applied to a gate electrode terminal, includes a deterioration detecting circuit configured to use one main electrode terminal of the two main electrode terminals of the semiconductor element with an applied DC voltage, as a reference potential, and detect deterioration of a joining part of the semiconductor element on the basis of a gate voltage which is the voltage between the one main electrode terminal and the gate electrode terminal and an inter-main-electrode voltage which is the voltage between the one main electrode terminal and the other main electrode terminal, and outputs an alarm signal.

A power conversion apparatus includes a semiconductor module including a semiconductor device and a control circuit unit controlling the semiconductor module. The semiconductor module has main and subsidiary semiconductor devices connected in parallel. The control circuit unit performs control such that the subsidiary semiconductor device is turned on after the main semiconductor device is turned on, and the main semiconductor device is turned off after the subsidiary semiconductor device is turned off. The control circuit unit performs control such that, one of the turn-on and turn-off switching timings has a switching speed faster than that of the other of the switching timings. The semiconductor module is configured such that, at a high-speed switching timing, an induction current directed to turn off the subsidiary semiconductor device is generated in a control terminal of the subsidiary semiconductor device depending on temporal change of a main current flowing to the main semiconductor device.

To provide an inductive load driving device which can control a clamp voltage using a ground voltage as a reference, with a simple structure. An inductive load driving device includes: an inductive load whose one end is connected to a power source and whose other end is connected to a ground: an output stage semiconductor switch element connected in series with the inductive load; a clamping circuit connected between a high-voltage side electrode and a control electrode of the output stage semiconductor switch element; and a resistance value control unit connected between the control electrode of the output stage semiconductor switch element and the ground.

To provide an inductive load driving device which can control a clamp voltage using a ground voltage as a reference, with a simple structure. An inductive load driving device includes: an inductive load whose one end is connected to a power source and whose other end is connected to a ground: an output stage semiconductor switch element connected in series with the inductive load; a clamping circuit connected between a high-voltage side electrode and a control electrode of the output stage semiconductor switch element; and a resistance value control unit connected between the control electrode of the output stage semiconductor switch element and the ground.

Circuitry for soft shutdown of a power switch and a power converters that includes circuitry for soft shutdown are described. In one aspect, circuitry for soft shutdown of a power switch includes a sense input to be coupled to a power switch receive a signal representative of current passing through the power switch, a comparator to compare the signal with an overcurrent threshold indicative of an overcurrent condition of the power switch and to output a triggering signal in response to the comparison indicating the overcurrent condition, and a gating transistor to be coupled to a control terminal of the power switch, the gating transistor configured to divert a portion of a drive signal away from the control terminal of the power switch in response to the triggering signal.

Circuitry for soft shutdown of a power switch and a power converters that includes circuitry for soft shutdown are described. In one aspect, circuitry for soft shutdown of a power switch includes a sense input to be coupled to a power switch receive a signal representative of current passing through the power switch, a comparator to compare the signal with an overcurrent threshold indicative of an overcurrent condition of the power switch and to output a triggering signal in response to the comparison indicating the overcurrent condition, and a gating transistor to be coupled to a control terminal of the power switch, the gating transistor configured to divert a portion of a drive signal away from the control terminal of the power switch in response to the triggering signal.

A bidirectional switch fault protection circuit includes a bidirectional switch circuit, a desaturation detection circuit, and a gate driver. The bidirectional switch circuit generates first and second switch voltages based on a direction of electric current. The desaturation detection circuit outputs the first switch voltage in response to the electric current flowing in a first direction and outputs the second switch voltage in response to the electric current flowing in a second direction opposite the first direction. The gate driver receives the first switch voltage in response to the electric current flowing in the first direction and the second switch voltage in response to the electric current flowing in the second direction. The gate driver detects a first short circuit condition based on the first switch voltage and a second short circuit condition based on the second switch voltage.

A bidirectional switch fault protection circuit includes a bidirectional switch circuit, a desaturation detection circuit, and a gate driver. The bidirectional switch circuit generates first and second switch voltages based on a direction of electric current. The desaturation detection circuit outputs the first switch voltage in response to the electric current flowing in a first direction and outputs the second switch voltage in response to the electric current flowing in a second direction opposite the first direction. The gate driver receives the first switch voltage in response to the electric current flowing in the first direction and the second switch voltage in response to the electric current flowing in the second direction. The gate driver detects a first short circuit condition based on the first switch voltage and a second short circuit condition based on the second switch voltage.