Seiko Instruments Inc

Sii Semiconductor Corporation

Ablic Inc.

Daisuke Muraoka

Minoru Ariyama

Tomoki Hikichi

Kentaro Fukai

Manabu Fujimura

Satoshi Machida

Tsutomu Tomioka

Masahiro Yokomichi

Masahiro Mitani

Daisuke Okano

Mihoko Yamashita

To reduce effects of noise and improve detection accuracy, a sensor device includes: a detection electrode opposing an external electrode to which a predetermined voltage is applied, and configured to generate a voltage corresponding to a change in electrostatic capacitance; and a capacitive amplifier circuit having a first capacitor and a second capacitor connected in series to each other, and configured to detect the voltage generated in the detection electrode, and output a detection signal obtained by amplifying the voltage generated in the detection electrode based on a capacitance ratio between the first capacitor and the second capacitor.

Sensor device

An output driver circuit provides an overcurrent protection function by a simple circuit configuration. The output driver circuit has a constant-current circuit, a constant-current mirror MOS transistor, and a selector circuit. The constant-current mirror MOS transistor and the output MOS transistor constitute a current mirror circuit. The gate of the output MOS transistor is controlled by a voltage based on a constant current generated by the constant-current mirror MOS transistor, thereby limiting the current flowing between the source and the drain of the output MOS transistor.

Output driver circuit

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 small-area photoelectric conversion device without impairing a resolution switching function, signals for controlling output order control switches provided so as to correspond to photoelectric conversion elements are selected by an output order control circuit and a shift register. In this manner, the number of flip-flops forming a shift register is reduced.

Photoelectric conversion device and image sensor

Provided is a magnetic sensor device, which is configured to connect each terminal of a Hall element to another end of a variable resistor having one end connected to GND by switching of four switches. Thus, a detection voltage level for a magnetic field intensity can be arbitrarily set with a small-scale circuit. The detection voltage level is determined only by the resistance ratio, and hence the influence of fluctuations in power supply voltage and manufacturing fluctuations can be suppressed. This configuration can simplify signal processing and achieve higher-speed signal processing.

Magnetic sensor device for generating an output in accordance with a magnetic field intensity applied to a magnetoelectric conversion hall effect element

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.

Magnetic sensor device

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.

Provided is a magnetic sensor device capable of suppressing a 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, to thereby achieve high-precision magnetic reading. The magnetic sensor device includes: a first D-type flip-flop and a second D-type flip-flop each having an input terminal connected to an output terminal of a comparator; an XOR circuit having a first input terminal and a second input terminal which are connected to an output terminal of the first D-type flip-flop and an output terminal of the second D-type flip-flop, respectively; a selector circuit; and a third D-type flip-flop having an input terminal connected to an output terminal of the selector circuit. The selector circuit includes: a first input terminal (A) and a second input terminal (B) which are connected to the output terminal of the second D-type flip-flop and an output terminal of the third D-type flip-flop, respectively; and a select terminal connected to an output terminal of the XOR circuit. The selector circuit selectively outputs input signals from the first input terminal (A) and the second input terminal (B), according to an output of the XOR circuit.

Provided is a constant current circuit capable of low current consumption operation, which is prevented from repeating a start-up state and a zero steady state and entering an oscillating state when power is activated. When power is activated, until a node (A) reaches a start-up state, an excitation current is continued to be supplied to a node (B), to thereby reliably start up the constant current circuit in a short period of time without repeating the start-up state and the zero steady state.

Constant current circuit start-up circuitry for preventing power input oscillation

Provided is a physical quantity sensor capable of improving physical quantity detection precision thereof. The physical quantity sensor includes a bridge resistance type physical quantity detection element for generating a voltage based on a bias current and a physical quantity, a current supply circuit for supplying the bias current to the physical quantity detection element, and a leakage current control circuit for causing leakage currents flowing when switches of the current supply circuit are in an off state to flow into a ground terminal.

Physical quantity sensor

Provided is a magnetic sensor device including: a switching circuit that controls switching of a terminal pair of the magnetoelectric conversion element to which a supply voltage is applied and a terminal pair to which detection voltage of a magnetic intensity is output; a differential amplifier that differentially amplifies the detection voltage; a first capacitor connected to a first output terminal of the differential amplifier; a second switch connected to a second output terminal of the differential amplifier; a comparator that has a first input terminal connected to the first capacitor and a second input terminal connected to the second switch; a first switch connected between the first input terminal and an output terminal of the comparator; and a second capacitor connected to the second input terminal of the comparator; and a detection voltage setting circuit connected to the second capacitor, in which effects of respective offset voltages of the magnetoelectric conversion element, the amplifier, and the comparator are suppressed, and an arbitrary detection magnetic field intensity is set to enable accurate magnetic reading.

Provided is a photoelectric converter capable of performing high-speed image reading and resolution switching at the same time. The photoelectric converter includes a plurality of common read lines, and thus parallel output is produced, which enables image reading at high speed. In addition, a photoelectric conversion block () is capable of communicating with another photoelectric conversion block (), whereby the common read lines, to which nodes (E) of a plurality of the photoelectric conversion blocks () adjacent to each other are connected, can be made the same. For this reason, voltages of those nodes (E) can be equalized in the same common read line, and hence switching between image resolutions can be realized.

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Chiba, Japan

Daisuke Muraoka