Seiko Instruments Inc

Ablic Inc.

Sii Semiconductor Corporation

Gakkouhoujin Chikoujigakuen

Atsushi Igarashi

Masakazu Sugiura

Nao Otsuka

Masahiro Mitani

Minoru Ariyama

Tsutomu Tomioka

Takashi Imura

Hirokazu Yoshizawa

Toshiyuki Uchida

Ryoichi Anzai

Akira Takeda

Kosuke Takada

Takao Nakashimo

Yuji Kobayashi

Takahiro Kato

Hideyuki Sawai

Hirotaka Uemura

Daisuke Okano

Yasuhiro Miyamoto

Naohiro Hiraoka

A magnetic sensor has a Hall IC that has a Hall element formed on a surface of the Hall IC, and a lead frame that supports the Hall IC. The lead frame includes a first region that is disposed in the vicinity of the Hall element and generates a first magnetic field due to a first eddy current generated when a measurement target magnetic field is applied, and second regions that are disposed away from the first region and generate a second magnetic field having an intensity that cancels the first magnetic field by means of second eddy currents generated when the measurement target magnetic field is applied.

Magnetic sensor and magnetic detection method

In order to provide a voltage abnormality detection circuit and a semiconductor device which are capable of detecting a voltage abnormality in an internal power supply voltage of the semiconductor device with a simple circuit configuration, the voltage abnormality detection circuit includes: a reference voltage circuit configured to output a first reference voltage, which is higher than the internal power supply voltage, and a second reference voltage, which is lower than the internal power supply voltage; a first voltage detection circuit configured to detect that the internal power supply voltage has exceeded a desired voltage value, with the use of the first reference voltage; and a second voltage detection circuit configured to detect that the internal power supply voltage has dropped lower than the desired voltage value, with the use of the second reference voltage.

Voltage abnormality detection circuit and semiconductor device

A current generation circuit includes: a current source circuit including a first transistor and a first resistor, and configured to output a first current based on a source voltage or a drain voltage of the first transistor and a resistance of the first resistor; a current control circuit including a voltage input terminal, a second transistor and a third transistor, and configured to output a second current based on a source voltage of the second transistor and a resistance of the third transistor; and an impedance circuit including a second resistor formed of a same resistive body as the first resistor and a fourth transistor diode-connected to the second resistor, and configured to generate a control voltage at the voltage input terminal by the first current and the second current, wherein the current generation circuit is configured to output a current based on the second current.

Current generation circuit

A secondary battery monitoring device is equipped with a resistance circuit and a detection circuit detecting an abnormality of a secondary battery, a current generation circuit generating a failure detection circuit for setting an output terminal of the resistance circuit to a failure diagnosis voltage, and a switch which permits the failure detection circuit to flow to the output terminal of the resistance circuit by switching. Further, a method for diagnosing failure of the secondary battery monitoring device is provided.

Secondary battery monitoring device and method for diagnosing failure

Provided is an overheat detection circuit configured to accurately detect a temperature of a semiconductor device even at high temperature and thus avoid outputting an erroneous detection result. The overheat detection circuit includes: a PN junction element, being a temperature sensitive element; a constant current circuit configured to supply the PN junction element with a bias current; a comparator configured to compare a voltage generated at the PN junction element and a reference voltage; a second PN junction element configured to cause a leakage current to flow through a reference voltage circuit at high temperature; and a third PN junction element configured to bypass a leakage current of the constant current circuit at the high temperature.

Overheat detection circuit and semiconductor device

Provided is a detection circuit configured to avoid erroneous detection that may occur immediately after a detection circuit is powered on. The detection circuit includes: an output transistor connected between a voltage input terminal and a voltage output terminal; and a load open-circuit detection circuit configured to detect an open circuit of a load connected to the voltage output terminal, in which an output circuit of the load open-circuit detection circuit includes a first transistor and a second transistor connected in series, the first transistor having a gate connected to the output transistor in common, the second transistor having a gate to which a signal indicating that the open-circuit of the load is detected, and in which the first transistor is in an off state when the output transistor is in an off state.

Detection circuit

To provide a current detection circuit capable of suppressing the occurrence of a large potential difference between input terminals of a differential amplifier circuit, and preventing degradation of input transistors. A differential amplifier circuit is equipped with a clamp circuit which limits gate-source voltages of a pair of PMOS transistors each having a bulk and a source connected to each other with the sources of the pair of PMOS transistors as input terminals.

Current detection circuit

Provided is a power supply voltage monitoring circuit capable of accurately detecting a power supply voltage with a small circuit scale and low power consumption. The power supply voltage monitoring circuit includes: a signal output circuit configured to output a signal voltage representing saturation characteristics with respect to an increase in power supply voltage; and a signal voltage monitoring circuit configured to output a signal representing that the signal voltage of the signal output circuit is normal, the signal voltage monitoring circuit including: a PMOS transistor including a gate connected to an output terminal of the signal output circuit; a first constant current circuit connected to a drain of the PMOS transistor; and an inverter including an input terminal connected to the drain of the PMOS transistor.

Power supply voltage monitoring circuit, and electronic circuit including the power supply voltage monitoring circuit

An output circuit has a smaller area and restrains outputs from becoming unstable even if a power supply voltage is lower than an operating voltage. A supply terminal of an inverter circuit is provided with switch circuit, and the switch circuit stops the operation of the inverter circuit when the power supply voltage is lower than the operating voltage of the circuit. Further, the output terminal of the inverter circuit is provided with a current source to fix the output to the power supply voltage when the operation of the inverter circuit is stopped.

Output circuit, temperature switch IC, and battery pack

Provided is a power supply switching circuit capable of suppressing a load fluctuation such as undershoot that occurs at an output terminal at the time of power supply switching. The power supply switching circuit includes: a battery connected to the output terminal; a replica current generation circuit for generating a replica current that is proportional to a current flowing from the battery to the output terminal; a voltage regulator connected to the output terminal, the voltage regulator including a reference voltage circuit, an error amplifier circuit, an output transistor, and a voltage divider circuit; and a current mirror circuit for causing the replica current to flow through the output transistor of the voltage regulator.

Power supply switching circuit

There is provided a level shift circuit free from malfunction. The level shift circuit converts a signal of a first power supply voltage of a first supply terminal, which is supplied to an input terminal, into a signal of a second power supply voltage of a second supply terminal and outputs the converted signal to an output terminal. The level shift circuit has a control circuit that detects when the first power supply voltage reduces below a predetermined voltage. The voltage of the output terminal of the level shift circuit is fixed to the second power supply voltage or a ground voltage according to a detection signal of the control circuit.

Level shift circuit

Provided is a power supply voltage monitoring circuit () including: a signal output circuit () for outputting a signal voltage (Vsignal) which exhibits a saturation characteristic with respect to an increase in a power supply voltage (VDD); and a signal voltage monitoring circuit () for comparing the power supply voltage (VDD) with the signal voltage (Vsignal), and outputting a signal (Vout) indicating that the signal voltage (Vsignal) is normal when there is a predetermined voltage difference. With this configuration, a minimum operating power supply voltage may be reduced in an electronic circuit, and the power supply voltage may be used with efficiency.

Power supply voltage monitoring circuit and electronic circuit including the power supply voltage monitoring circuit

Provided is a temperature sensor device operable at a lower voltage. The temperature sensor device detects temperature based on an output voltage of a forward voltage generator for generating a forward voltage of a PN junction. The forward voltage generator includes a level shift voltage generation circuit, and an output voltage of the temperature sensor device is given based on the forward voltage of the PN junction and a voltage of the level shift voltage generation circuit.

Temperature sensor device

Provided is a temperature detection device capable of attaining low current consumption at no expense of detection speed at around a temperature to be detected. The temperature detection device includes a control circuit for outputting a control signal for controlling ON/OFF of such internal circuits as a reference voltage circuit and a comparator. In the control circuit, in order to increase the detection speed at around the temperature to be detected, an oscillation frequency of an oscillation circuit has positive temperature characteristics. Further, the control circuit includes a waveform shaping circuit so as to optimize the waveform of the control signal for controlling ON of the internal circuits, to thereby attain low current consumption.

Temperature detection device

Provided is a constant current circuit and a reference voltage circuit with improved line regulation without needing a start-up circuit. The constant current circuit includes: a constant current generation circuit including NMOS transistors and a resistor; a current mirror circuit including a pair of depletion mode NMOS transistors, for allowing a current of the constant current generation circuit to flow; and a feedback circuit for maintaining constant voltages of source terminals of the pair of depletion mode NMOS transistors.

Growing community of inventors

Chiba, Japan

Atsushi Igarashi