Rohm Co., Ltd.

Shuntaro Takahashi

Toru Takuma

Naoki Takahashi

Hajime Okuda

Kazuki Okuyama

Motoharu Haga

Shingo Yoshida

Hirofumi Yuki

Kazuhisa Kumagai

Tetsuo Yamato

Yoshinori Fukuda

Muga Imamura

Adrian Joita

Katsuaki Yamada

Makoto Sada

Hiroshi Furutani

A semiconductor device includes a semiconductor layer, an insulation gate-type first transistor which is formed in the semiconductor layer, an insulation gate-type second transistor which is formed in the semiconductor layer, and a control wiring which is formed on the semiconductor layer such as to be electrically connected to the first transistor and the second transistor, and transmits control signals that control the first transistor and the second transistor to be in ON states in a normal operation and that control the first transistor to be in an OFF state and the second transistor to be in an ON state in an active clamp operation.

Semiconductor device including insulation gate-type transistors

A semiconductor device includes: a split-gate transistor connected between a drain electrode (output electrode OUT) and a ground electrode and having a plurality of individually controllable channel regions; an active clamp circuit configured to limit the output voltage VOUT appearing at the output electrode to a clamp voltage or below; and a gate control circuit configured to raise the ON resistance of the split-gate transistor gently (or stepwise) after the split-gate transistor is switched from the ON state to the OFF state before the active clamp circuit limits the output voltage VOUT.

Semiconductor device

A switching device includes: an N-type semiconductor substrate; a power MISFET having the N-type semiconductor substrate as its drain; an input electrode receiving an input signal; a control circuit generating a gate control signal for the power MISFET according to the input signal; and a negative current prevention circuit provided between the input electrode and the control circuit. The negative current prevention circuit includes: a P-channel MISFET connected, with its drain toward the input electrode and its source and back gate toward the control circuit, between the input electrode and the control circuit, with its gate fed with a fixed potential, with the potential at its back gate separated from the potential of the N-type semiconductor substrate; and a diode connected, with its anode toward the input electrode and its cathode toward the control circuit, between the input electrode and the control circuit.

Switching device, electronic appliance, and vehicle

Disclosed is a gate control circuit that generates a gate control signal of an output transistor connected between an application end of a power supply voltage and an application end of an output voltage. The gate control circuit includes a first current source connected between the application end of the power supply voltage and the application end of the output voltage, a second current source connected between an application end of a booster voltage and an application end of a reference voltage, the booster voltage being raised to a voltage value higher than the power supply voltage in a steady state, an output stage that uses at least one of the first and second current sources to generate a gate charge current for charging a gate of the output transistor, and a controller that uses at least one of the first and second current sources according to the output voltage.

Gate control circuit, semiconductor device, electronic apparatus, and vehicle

In order both to accommodate instantaneous current as well as overcurrent protection in accordance with the load, an overcurrent protection circuit has: a threshold value generation unit that, in accordance with a threshold value control signal, switches between setting an overcurrent detection threshold value to a first set value (∝ Iref) and a second set value (∝ Iset) lower than the first set value; an overcurrent detection unit that compares a sense signal in accordance with the current being monitored and the overcurrent detection value and generates an overcurrent protection signal; a reference value generation unit that generates a reference value (∝ Iset) in accordance with the seconds set value; a comparison unit that compares the sense signal and the reference value, and generates a comparison signal; and a threshold value control unit that monitors the comparison signal, and generates a threshold value control signal.

Overcurrent protection circuit

A semiconductor device includes a semiconductor element and a first connection member. The semiconductor element includes a substrate and an electrode pad. The substrate includes a transistor formation region, in which a transistor is formed and which is shaped to be non-quadrangular. The electrode pad is located on the transistor formation region. The first connection member is connected to the electrode pad at one location. The electrode pad is arranged to cover a center of gravity of the transistor formation region in a plan view of the electrode pad. In the plan view, a connection region in which the first connection member is connected to the electrode pad includes a center of gravity position of the transistor formation region.

Disclosed is a switch device including a first terminal, a second terminal, a third terminal, a switch element disposed between the first terminal and the second terminal, a control line that reaches a control end of the switch element from the third terminal, a first circuit block that is disposed on the control line and is configured to drive the switch element according to a control signal supplied to the third terminal, at least one second circuit block, each second circuit block being connected to a corresponding one of branch power supply lines that branch from the control line, a first resistor disposed between the third terminal and the first circuit block, and at least one second resistor, each second resistor being disposed on a corresponding one of the branch power supply lines.

Switch device, electronic equipment, and vehicle

An overcurrent protection circuit includes a current control part configured to control conductance of a transistor so as to limit an output current flowing when the transistor is turned on to a predetermined upper limit or less, and a duty control part configured to forcibly turning on/off the transistor at a predetermined duty ratio when a temperature protection circuit detects a temperature abnormality in a state where the current control part limits the output current.

In order both to accommodate instantaneous current as well as overcurrent protection in accordance with the load, an overcurrent protection circuit has: a threshold value generation unit that, in accordance with a threshold value control signal, switches between setting an overcurrent detection threshold value to a first set value (&#x221d; Iref) and a second set value (&#x221d; Iset) lower than the first set value; an overcurrent detection unit that compares a sense signal in accordance with the current being monitored and the overcurrent detection value and generates an overcurrent protection signal; a reference value generation unit that generates a reference value (&#x221d; Iset) in accordance with the seconds set value; a comparison unit that compares the sense signal and the reference value, and generates a comparison signal; and a threshold value control unit that monitors the comparison signal, and generates a threshold value control signal.

In order both to accommodate instantaneous current as well as overcurrent protection in accordance with the load, an overcurrent protection circuit has: a threshold value generation unit that, in accordance with a threshold value control signal, switches between setting an overcurrent detection threshold value to a first set value (&#x221d;Iref) and a second set value (&#x221d;Iset) lower than the first set value; an overcurrent detection unit that compares a sense signal in accordance with the current being monitored and the overcurrent detection value and generates an overcurrent protection signal; a reference value generation unit that generates a reference value (&#x221d;Iset) in accordance with the seconds set value; a comparison unit that compares the sense signal and the reference value, and generates a comparison signal; and a threshold value control unit that monitors the comparison signal, and generates a threshold value control signal.

A protection circuit includes: a high-side switch connected to a power terminal to which a predetermined power supply voltage VBB is supplied from an onboard battery; and an NMOS transistor MTconnected to the high-side switch and configured to prevent an electrical conduction to the high-side switch when the onboard battery is reverse-connected to the power terminal, wherein a semiconductor integrated circuit is protected from a breakdown due to the reverse connection of the external power supply. A semiconductor integrated circuit apparatus includes the above-mentioned protection circuit configured to protect a semiconductor integrated circuit connected between the power terminal and the ground terminal, from an electro-static discharge breakdown. The protection circuit is connected to the clamp circuit unit inserted between the power terminal and the ground terminal, and is configured to protect the clamp circuit unit from a breakdown when the external power supply is reverse-connected.

Protection circuit and operational method of the protection circuit, and semiconductor integrated circuit apparatus

A switching device has, for example, a first terminal configured to be connected to an application node for a first voltage, a second terminal configured to be connected to the first end of a load, a third terminal configured to be connected to the second end of the load and to an application node for a second voltage, a switching element configured to be connected between the first and second terminals, a first active clamper configured to limit the output voltage at the second terminal with reference to the first voltage in a first state, and a second active clamper configured to limit the output voltage with reference to the second voltage in a second state different from the first state.

Growing community of inventors

Kyoto, Japan

Shuntaro Takahashi