Ablic Inc.

Seiko Instruments Inc

Sii Semiconductor Corporation

Kentaro Fukai

Tomoki Hikichi

Minoru Ariyama

Daisuke Muraoka

Takemasa Miura

The semiconductor device includes a Hall element, a first differential pair, a second differential pair, an output amplifier circuit, and a voltage divider circuit. The Hall element outputs a signal that is dependent on stress to be applied to a semiconductor substrate to the first differential pair. The voltage divider circuit divides a voltage into a divided voltage having a voltage dividing ratio that is dependent on the stress. The first differential pair outputs a first current based on the signal. The second differential pair outputs a second current based on the divided voltage and a reference voltage. The output amplifier circuit outputs a voltage based on the first and second currents. A gain of the output amplifier circuit is approximated by a sum of a difference between stress dependence coefficients of transconductances of the first and second differential pairs and a stress dependence coefficient of the voltage dividing ratio.

Semiconductor device

A semiconductor device formed on a semiconductor substrate of a P type includes: a vertical resistor circuit including a resistor of an N type, the resistor forming a current path in a direction perpendicular to a surface of the semiconductor substrate; a Hall element provided on the semiconductor substrate, the Hall element being configured to supply a voltage proportional to a magnetic flux density in the direction perpendicular to the surface of the semiconductor substrate; an amplifier configured to amplify the voltage supplied from the Hall element, and supply the amplified voltage; a current/voltage conversion circuit configured to supply, as a comparison reference voltage, a voltage containing a product of a reference current IREF flowing through the vertical resistor circuit and a resistance value RREF of the vertical resistor circuit; and a comparator configured to receive the voltage supplied from the amplifier and the comparison reference voltage.

A stress compensation control circuit of the present invention is provided which is capable of using a compensation error similar to that at room temperature even at a high temperature and reducing the area of a chip for a semiconductor sensor as compared with the related art. The stress compensation control circuit compensates for a change in detection sensitivity due to a stress to be applied to the semiconductor sensor. The stress compensation control circuit includes a stress compensation voltage generating circuit generating a stress compensation voltage corresponding to the applied stress in accordance with a difference between changes in transconductance due to stresses in a first depletion transistor and a first enhancement transistor, and performs compensation for the detection sensitivity in correspondence to the stress applied to the semiconductor sensor.

Stress compensation control circuit and semiconductor sensor device

Provided are a magnetic sensor, which is capable of accurately determining abnormalities, such as disconnection and a short circuit, of wiring of a magnetic sensor device, and the magnetic sensor device. An output control circuit of the magnetic sensor includes a voltage divider circuit, which is connected to an output terminal of the magnetic sensor, and an amplifier, which is configured to control a gate voltage of a MOS transistor, which is connected to the output terminal of the magnetic sensor, so that a voltage of the voltage divider circuit and a reference voltage become equal to each other, with the result that an output voltage of the magnetic sensor is determined by the reference voltage and a voltage dividing ratio of the voltage divider circuit.

Magnetic sensor and magnetic sensor device

To provide a magnetic sensor which is reduced in power consumption without reducing magnetism detection sensitivity of a magnetoelectric transducing element. One end of a magnetoelectric transducing element is connected to an output electrode of a constant current circuit, and the other end thereof is connected to a power supply electrode on the positive side of one or plural signal processing circuits, and the like built in a magnetic sensor, whereby a connection relation of the magnetoelectric transducing element and the signal processing circuit is configured such that they are connected in series with a voltage source.

Magnetic sensor

To provide a magnetic sensor circuit that outputs a desired detection pulse while preventing an erroneous detection/erroneous release pulse output when a fluctuation in a power supply voltage occurs within an operating power supply voltage range. A magnetic sensor circuit is configured to include a detection circuit that detects a fluctuation in a power supply voltage or an internal power supply voltage and so as not to latch a determination output of a comparator by a latch circuit that, on the basis of a power supply fluctuation detection signal output from the detection circuit, holds the logic of a control clock signal output from an oscillation circuit for a prescribed period of time and determines the output logic of an output terminal.

Magnetic sensor circuit with power supply fluctuation detection

To provide a magnetic sensor device which maintains accuracy thereof while reducing current consumption by switching drive power of a Hall element to two drive power. A magnetic sensor device is equipped with a driving circuit which supplies power to a sensor element, a switch changeover circuit which restricts the supply of the power from the driving circuit to the sensor element, a differential amplifier circuit which performs arithmetic processing on an output signal of the sensor element, a threshold voltage generating circuit which generates a threshold voltage used in magnetism determination, a comparison circuit which compares and determines a voltage of the differential amplifier circuit and the threshold voltage, and a logic circuit which according to the output of the comparison circuit, switches the power outputted from the driving circuit, switches the threshold voltage and controls on/off of the switch changeover circuit in a constant cycle.

Magnetic sensor device

The sensor device includes: a physical quantity voltage conversion element; a differential amplifier; a first capacitor that includes one terminal connected to a first output terminal of the differential amplifier; a comparator; a low pass filter circuit arranged at the first output terminal of the differential amplifier; a control circuit configured to on/off control the physical quantity voltage conversion element, the differential amplifier, the comparator, and the low pass filter circuit; and a logic circuit configured to output a result of operation processing performed on an output signal of the comparator. The logic circuit is configured to: successively verify, in a case where there is a change between a previous logic output and a first logic output, the logic outputs a plurality of times; and output a control signal to the control circuit so that the low pass filter circuit is turned on in a second signal processing period and thereafter.

Sensor device

Provided is a magnetic sensor device capable of performing signal processing at high speed with high accuracy. The magnetic sensor device includes: a plurality of Hall elements; a plurality of differential amplifiers to which the plurality of Hall elements are connected, respectively; a detection voltage setting circuit for outputting a reference voltage; and a comparator including: a plurality of differential input pairs connected to the plurality of differential amplifiers, respectively; and a differential input pair connected to the detection voltage setting circuit.

Provided is a sensor device capable of removing the influence of each offset voltage of a sensor element, a differential amplifier, and an amplifier of the sensor device, to thereby detect a physical quantity with high precision and respond to high-speed operation. The sensor device includes: a switch circuit connected to a first terminal pair and a second terminal pair of the sensor element, for controlling switching of the terminal pairs and outputting signal voltages; a differential amplifier including a first input terminal and a second input terminal connected to a first output terminal and a second output terminal of the switch circuit, respectively, for outputting a result obtained by amplifying a difference of the signal voltages; an amplifier including at least two differential input pairs, one of which inputs the differential signal output from the differential amplifier, and at least one of which inputs a reference signal corresponding to a physical quantity to be detected; and a detection voltage setting circuit for outputting the reference signal to the amplifier. Switching of the switch circuit provides a first detection state and a second detection state, and detection is performed in one first detection state and one second detection state.

Provided is a sensor device capable of removing the influence of each offset voltage of a sensor element, a differential amplifier, and an amplifier of the sensor device, to thereby detect a physical quantity with high precision. The sensor device includes: a switch circuit, which is connected to a first terminal pair and a second terminal pair of the sensor element, for controlling switching of the terminal pairs and outputting detection voltages; a differential amplifier, which includes a first input terminal and a second input terminal connected to a first output terminal and a second output terminal of the switch circuit, respectively, for outputting a result obtained by amplifying a difference of the detection voltages; an amplifier including at least two differential input pairs, one of which inputs the differential signal output from the differential amplifier, and at least one of which inputs a reference signal corresponding to a physical quantity to be detected; and a detection voltage setting circuit for outputting the reference signal to the amplifier.

A magnetic sensor device for generating a logic output in accordance with a magnetic field intensity applied to a magnetoelectric conversion element includes: a comparator for inputting amplified output signals of the magnetoelectric conversion element, and outputting a comparison result; and a logic circuit for performing arithmetic processing on an output signal of the comparator. Only when the logic output is changed by a change in the magnetic field intensity, the logic circuit performs successive matching determination of logic outputs a plurality of times. Thus, the variation in determination for detection or canceling of a magnetic field intensity, which is caused by noise generated from respective constituent elements included in the magnetic sensor device and external noise, may be reduced while suppressing electric power consumption.

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Chiba, Japan

Kentaro Fukai