Abstract: An integrated circuit for controlling an ignition system including a coil. The integrated circuit includes a transistor configured to control a current flowing through the coil, a first line coupled to a control electrode of the transistor, a second line coupled to an electrode of the transistor on the ground side thereof, a control circuit configured to control on and off of the transistor based on a voltage level of the first line, and a Zener diode having a cathode coupled to the first line and an anode coupled to the second line. The Zener diode has such a capacitance that, when a first signal, and a second signal of a higher frequency, are inputted to the first line, the control circuit controls the on and off of the transistor in response to the first signal irrespective of the second signal.

Abstract: A semiconductor integrated circuit including a power switch element, a control circuit connected to the power switch element, an electrostatic discharge protection device connected to an input terminal to which an input voltage is applied, for protecting the power switch element and the control circuit from being damaged by an electrostatic discharge, and a short-to-supply fault protection circuit connected to the electrostatic discharge protection device, for protecting the power switch element and the control circuit from being damaged by a high voltage. The short-to-supply fault protection circuit includes a first step-down circuit disposed between the input terminal and the control circuit, and a second step-down circuit disposed between the input terminal and a gate of the power switch element. Each of the first and second step-down circuits, upon detecting the high voltage, steps down the high voltage for the control circuit or the power switch element.

Abstract: A semiconductor integrated circuit includes a semiconductor power switch element configured to drive an 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 turned on, 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, which is lower than the first withstand voltage, upon receiving the logic signal.

Abstract: A semiconductor device includes a power semiconductor switching element including a characteristic test terminal, and a control circuit configured to control an operation of the power semiconductor switching element. The power semiconductor switching element and the control circuit are formed in a same chip. The control circuit includes a gate voltage generation circuit configured to generate a current limit gate voltage for restricting an overcurrent flowing in the power semiconductor switching element in a desired range when an abnormality occurs, based on a characteristic of the power semiconductor switching element which is measured in advance by applying a voltage to the characteristic test terminal.

Abstract: A semiconductor integrated circuit includes a semiconductor power switch element configured to drive an 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 turned on, 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, which is lower than the first withstand voltage, upon receiving the logic signal.

Abstract: A semiconductor integrated circuit including a power switch element, a control circuit connected to the power switch element, an electrostatic discharge protection device connected to an input terminal to which an input voltage is applied, for protecting the power switch element and the control circuit from being damaged by an electrostatic discharge, and a short-to-supply fault protection circuit connected to the electrostatic discharge protection device, for protecting the power switch element and the control circuit from being damaged by a high voltage. The short-to-supply fault protection circuit includes a first step-down circuit disposed between the input terminal and the control circuit, and a second step-down circuit disposed between the input terminal and a gate of the power switch element. Each of the first and second step-down circuits, upon detecting the high voltage, steps down the high voltage for the control circuit or the power switch element.

Abstract: A semiconductor device includes an input determination circuit. The input determination circuit includes: a comparator that is driven based on a first reference potential and includes an input voltage terminal and a reference voltage terminal; a reference voltage generation circuit that inputs a reference voltage that is generated from a connection point between a constant current source and a resistor to the reference voltage terminal of the comparator, the constant current source and the resistor being interposed between a second reference potential that is separated from the first reference potential and a third potential that is higher than the first reference potential and the second reference potential; and a first low pass filter that is interposed between a signal input system that is connected to the input voltage terminal of the comparator and the second reference potential.

Abstract: A semiconductor device includes an element drive unit configured to control a control terminal of a voltage-control type semiconductor element using the control signal as input, the element drive unit including a control circuit that is driven using the control signal as a power supply. The element drive unit includes: a first voltage divider circuit that is connected between an input terminal to which the control signal is input and a low potential side terminal connected to a low potential side terminal of the voltage-control type semiconductor element and is configured such that a first divided voltage is not greater than a set voltage; a semiconductor switching element configured to control the first voltage divider circuit; and a second voltage divider circuit for making the semiconductor switching element conductive. The first divided voltage is supplied to the control terminal of the voltage-control type semiconductor element and the control circuit.

Abstract: A semiconductor device includes a power semiconductor switching element including a characteristic test terminal, and a control circuit configured to control an operation of the power semiconductor switching element. The power semiconductor switching element and the control circuit are formed in a same chip. The control circuit includes a gate voltage generation circuit configured to generate a current limit gate voltage for restricting an overcurrent flowing in the power semiconductor switching element in a desired range when an abnormality occurs, based on a characteristic of the power semiconductor switching element which is measured in advance by applying a voltage to the characteristic test terminal.

Abstract: A semiconductor integrated circuit for controlling a power switch in accordance with a control signal, which is at one of a first level and a second level for respectively turning on and off the power switch. The semiconductor integrated circuit includes a control circuit configured to receive the control signal to thereby output a reference voltage, a value of which gradually drops from a predetermined value when the received control signal remains at the first level for a predetermined time, a current sensing circuit configured to sense a current flowing through the power switch, and a drive circuit configured to receive the control signal and the reference voltage to thereby output a drive signal, the drive signal limiting the current flowing through the power switch in accordance with the reference voltage and a sense voltage corresponding to the current sensed by the current sensing circuit.

Abstract: A semiconductor device includes an input determination circuit. The input determination circuit includes: a comparator that is driven based on a first reference potential and includes an input voltage terminal and a reference voltage terminal; a reference voltage generation circuit that inputs a reference voltage that is generated from a connection point between a constant current source and a resistor to the reference voltage terminal of the comparator, the constant current source and the resistor being interposed between a second reference potential that is separated from the first reference potential and a third potential that is higher than the first reference potential and the second reference potential; and a first low pass filter that is interposed between a signal input system that is connected to the input voltage terminal of the comparator and the second reference potential.

Abstract: A semiconductor device includes an element drive unit configured to control a control terminal of a voltage-control type semiconductor element using the control signal as input, the element drive unit including a control circuit that is driven using the control signal as a power supply. The element drive unit includes: a first voltage divider circuit that is connected between an input terminal to which the control signal is input and a low potential side terminal connected to a low potential side terminal of the voltage-control type semiconductor element and is configured such that a first divided voltage is not greater than a set voltage; a semiconductor switching element configured to control the first voltage divider circuit; and a second voltage divider circuit for making the semiconductor switching element conductive. The first divided voltage is supplied to the control terminal of the voltage-control type semiconductor element and the control circuit.

Abstract: A semiconductor integrated circuit for controlling a power switch in accordance with a control signal, which is at one of a first level and a second level for respectively turning on and off the power switch. The semiconductor integrated circuit includes a control circuit configured to receive the control signal to thereby output a reference voltage, a value of which gradually drops from a predetermined value when the received control signal remains at the first level for a predetermined time, a current sensing circuit configured to sense a current flowing through the power switch, and a drive circuit configured to receive the control signal and the reference voltage to thereby output a drive signal, the drive signal limiting the current flowing through the power switch in accordance with the reference voltage and a sense voltage corresponding to the current sensed by the current sensing circuit.

Abstract: An internal combustion engine ignition device can determine ignition timing with high precision to perform ignition with high precision even where noise superimposed at the time of rise of current flowing through an ignition coil is generated. In an internal combustion engine ignition device including an output terminal for detecting an internal state such as a coil current, it is possible to prevent generation of pulse noise in the form of chattering at falling and rising edges of a voltage of the output terminal by using a hysteresis comparator, even if noise is superimposed at the time of rise of the coil current. Therefore, a voltage pulse with pulse width of high precision is transmitted to an electronic control unit without the influence of noise, and the ignition timing can be determined properly with high precision.

Abstract: A regulator circuit that makes it possible to supply a voltage which enables a load circuit to operate normally, even if an external power supply voltage is momentarily interrupted or dropped, includes a ZD/R parallel circuit (a backflow prevention diode and in parallel with a resistor) that is connected between an external power supply voltage terminal and the drain of a MOSFET.

Abstract: In some aspects of the invention, provided is a semiconductor device capable of compensating sufficiently instantaneous drop of power source voltage without enlarging device scale extremely. When digital circuit and power device driving circuit are formed on chip in the state connected to power source in common in parallel, for digital circuit of functional circuit remaining abnormal state after power source recovery and analog circuit and power device driving circuit of functional circuit retaining continuously normal state even before power source recovery, resistors are formed on chip in power source E side of the functional circuits, and in addition, capacitors are formed on chip 1 in parallel with the functional circuits, and consequently, it becomes possible to enlarge each resistance value of resistors as compared with a case of attaching externally resistors and capacitors in the entire chip.

Abstract: The present invention copes with fluctuations in a power supply voltage when a capacitor for coping with fluctuations in the power supply voltage has been omitted and also cases in which the power supply voltage is constantly low, thereby ensuring driving of an active element. A gate driving device of an IGBT includes: a first switch portion which turns on the IGBT; a second switch portion which turns off the IGBT; a current control portion which controls the outflow of charge on the gate to a ground line such that current is constant; a first protection circuit which suppresses outflow of gate current to the power supply line; and a second protection circuit which detects a prescribed fluctuation in an internal power supply voltage Vdc, and interrupts the connection between the current control portion and the ground line.

Abstract: In some aspects of the invention, provided is a semiconductor device capable of compensating sufficiently instantaneous drop of power source voltage without enlarging device scale extremely. When digital circuit and power device driving circuit are formed on chip in the state connected to power source in common in parallel, for digital circuit of functional circuit remaining abnormal state after power source recovery and analog circuit and power device driving circuit of functional circuit retaining continuously normal state even before power source recovery, resistors are formed on chip in power source E side of the functional circuits, and in addition, capacitors are formed on chip 1 in parallel with the functional circuits, and consequently, it becomes possible to enlarge each resistance value of resistors as compared with a case of attaching externally resistors and capacitors in the entire chip.

Abstract: A regulator circuit that makes it possible to supply a voltage which enables a load circuit to operate normally, even if an external power supply voltage is momentarily interrupted or dropped, includes a ZD/R parallel circuit (a backflow prevention diode and in parallel with a resistor) that is connected between an external power supply voltage terminal and the drain of a MOSFET.

Abstract: The present invention copes with fluctuations in a power supply voltage when a capacitor for coping with fluctuations in the power supply voltage has been omitted and also cases in which the power supply voltage is constantly low, thereby ensuring driving of an active element. A gate driving device of an IGBT includes: a first switch portion which turns on the IGBT; a second switch portion which turns off the IGBT; a current control portion which controls the outflow of charge on the gate to a ground line such that current is constant; a first protection circuit which suppresses outflow of gate current to the power supply line; and a second protection circuit which detects a prescribed fluctuation in an internal power supply voltage Vdc, and interrupts the connection between the current control portion and the ground line.