Hitachi Automotive Systems, Ltd.

Hitachi, Ltd.

Satoshi Asano

Masahiro Matsumoto

Hiroshi Nakano

Keiji Hanzawa

Shinobu Tashiro

Akira Kotabe

Yoshimitsu Yanagawa

Yasuo Onose

Akihiko Kanouda

Yuki Kawaguchi

Takae Shimada

Ryosuke Doi

Kazunori Suzuki

Yasushi Okada

A semiconductor chip having a pad, a protective element, and an internal circuit for providing a semiconductor chip having a protective circuit with high noise resistance, wherein the semiconductor chip is characterized in that the resistance value of metal wiring on a path reaching the pad and the protective element is higher than the resistance value of the protective element.

Semiconductor chip having on-chip noise protection circuit

Provided is an airflow meter with good precision. In the airflow meter, which is provided with an arithmetic circuit that incorporates air temperature and a sensor module temperature as adjustment elements for the output characteristics of the airflow meter, corrects the output characteristics in accordance with the temperature difference between the air temperature and the sensor module temperature and reduces the correction amount when the absolute value of the difference between the air temperature and the sensor module temperature is small.

Airflow meter

In configurations in which a circuit element is connected in parallel with a resistor, it is difficult to detect a break in the two wires. A thermal flow meter includes a heating element and a temperature controlling bridge circuit that is formed of a plurality of resistors and controls the temperature of the heating element. The thermal flow meter includes: a circuit element connected in parallel with at least one resistor configuring the temperature controlling bridge circuit through two wires drawn from both ends of the resistor; a voltage detection circuit that detects that the magnitude of voltage produced between the two wires has become smaller than a first predetermined value; and a fault signal output circuit that, when it is detected at the voltage detection circuit that the. magnitude of the voltage has become smaller than the first predetermined value, outputs a signal indicating a fault.

Thermal flow meter

Provided is a sensor device wherein malfunction due to a negative surge is suppressed. This sensor device is provided with: a sensor element wherein electrical characteristics change corresponding to physical quantities; a signal processing circuit that processes output signals of the sensor element; a first transistor element that supplies currents to the sensor element and the signal processing circuit; a control circuit that controls a base current of the first transistor element; a power supply terminal; and a ground terminal. The sensor device is characterized in that the control circuit is provided with a limiting section that limits a current flowing from the ground terminal toward a base terminal of the first transistor element.

Sensor device

A gas sensor includes a first heating element and a second heating element that is formed around the periphery of the first heating element and has a wider forming area than the first heating element. A gas amount is measured by heating the first heating element to a predetermined temperature, in which the second heating element is heated when the gas sensor is activated, and the first heating element is heated to the predetermined temperature after a heat value of the first heating element is restricted for a predetermined period of time.

Gas sensor

To provide a gas sensor apparatus capable of preventing clogging of a gas intake port due to particles, droplets, or the like, of a gas and maintaining measurement accuracy for a long time, a gas sensor apparatusincludes a housing. The housingincludes an expansion chambercommunicating with an air intake passagevia an air intake port, and a measurement chambercommunicating with the expansion chambervia a communicating portion. A double squeezing structure including the gas intake portand the communicating portionis provided, and two stages of regions where the volume expands between the gas intake portand the measurement chamberare provided. As a result, the movement of the air in the measurement chamberis decreased. It is possible to provide a structure in which the capacity of the gas intake portis increased to avoid clogging of the gas intake port due to particles or droplets.

Gas sensor apparatus and installation structure of gas sensor apparatus

A gas sensor device of the present invention, aiming sufficient correction results of an internal combustion engine under different operation conditions, includes a concentration sensor for measuring the concentration of gas and a pressure sensor for measuring the pressure of the gas. The gas sensor device also includes a measuring chamber incorporating the concentration sensor and the pressure sensor, and a processing circuit unit that adjusts a signal of the concentration sensor using a signal of the pressure sensor. The processing circuit unit may preferably be provided with a response speed adjusting unit that brings the response speed of a detected signal of the pressure sensor close to the response speed of a detected signal of the concentration sensor.

Gas sensor device

In order to achieve measurement with high precision by suitably correcting a measurement error, a hot-type fluid measurement device includes a module having a passage section and a circuit chamber, a sensor element disposed in the passage section, and a circuit element disposed in the circuit chamber. The circuit element includes a correction section that corrects flow rate information detected by the sensor element from temperature difference information of a temperature of a fluid and a temperature of the module, and at least one temperature of the temperature of the fluid or the temperature of the module.

Hot-type fluid measurement device with electronic elements

Provided is a sensor device that suppresses a malfunction caused by a negative surge or a voltage drop. A sensor device includes a sensor element having an electrical characteristic varying according to a physical amount, a signal processing circuit configured to process an output signal of the sensor element, a transistor element interposed between a power source terminal and the signal processing circuit, a resistive element configured to connect a drain and a gate of the transistor element, or a collector and a base of the transistor element, and an element having threshold voltage for connecting the gate or the base of the transistor element to a GND. The element regulates current flowing from the resistive element in a direction of the GND, in a case in which supply voltage to the signal processing circuit falls below the threshold voltage.

In order to provide a thermal mass flowmeter which makes higher accuracy of gas flowrate measurement possible while reliability in the thermal mass flowmeter is ensured (while deterioration or breakage caused by droplet adhesion is prevented), the thermal mass flowmeter according to the present invention has a heating element for generating heat by conduction, a temperature detection bridge circuit for detecting a temperature of the heating element, and a sensor element driving circuit portion connected to the heating element and the temperature detection bridge circuit and executing conduction control to the heating element, in which the sensor element driving circuit portion has an output mechanism and an output impedance adjustment mechanism and the output impedance adjustment mechanism is disposed between the output mechanism and the heating element and its output impedance is higher than an electric resistance value of the heating element and less than 1 M&#x3a9;.

Thermal mass flowmeter

Provided is a thermal type flowmeter in which contamination of a sensor element is reduced. The flowmeter includes a sensor element including a heating resistor formed in a thin film part, the thin film part being provided on a diaphragm formed on a substrate; a support member to locate the sensor element thereon; a secondary channel that includes part of the support member and takes in part of intake air flowing through an air intake pipeline; and a guide member provided on the support member or the sensor element that lies on a line L that extends along an air flow in the secondary channel and passing over the thin film part, the guide member allowing fine particles to be guided in a direction away from the line L, the fine particles coming together with an air flow along the surface of the support member or the sensor element.

Thermal type flowmeter with particle guide member

A flow rate measuring device with high precision is provided. The flow rate measuring device includes a sub-passage that takes a part of the fluid flowing in a main passage, first temperature measuring means for measuring a temperature of the fluid flowing in the passage, second temperature measuring means for measuring a temperature of a fluid flowing in the sub-passage, detecting means for detecting a flow rate of the fluid flowing in the sub-passage, and measuring means for measuring a flow rate of the fluid flowing within the main channel on the basis of an output of the first temperature measuring means, an output of the second temperature measuring means, and an output of the detecting means.

Flow rate measuring device with first temperature sensor in a main passage and second temperature sensor in a sub-passage

A fluid measurement device includes a circuit unit into which a first signal output from a first detection element and a second signal output from a second detection element are input. The circuit unit includes a signal processing part, a state deciding part, and a controller. The controller controls an amount of change that a change of the first signal imparts to the third signal in accordance with a result of decision by the state deciding part that determines that the state of the first signal is not within the predetermined range. The predetermined range is based on the second signal.

Fluid measurement device having a circuit for precise flow measurement

In a related art sensor device, an output voltage of the sensor device is fixed not to a power supply voltage or a ground potential but to an intermediate potential upon disconnection of a power supply line or a ground line. A sensor deviceis composed of: a detection elementwhose voltage Vsen changes depending on a detected physical quantity; an output circuit configured by MOS switchestoandto, capacitorsand, an operational amplifier, a reference voltage source, and output NMOS transistor; a series circuit of the MOS switchand the capacitor, the series circuit being arranged in a negative feedback part of the output circuit; and a diodethat connects a well electrode of the MOS switchand a power supply terminal Vcc.

Sensor device with series circuit of MOS switch and capacitor

Disclosed is a charging system for both plug-in charging systems and contactless charging systems, having a simple electrical configuration, and capable of achieving miniaturization and weight saving. The charging system includes a secondary cell charged via first/second coils of a transformer to which electrical power is supplied from a first power supply via a plug-in connector, and a third coil supplied with electrical power from a second power supply, a relative position of which to the second coil of the transformer is variable, and which can be magnetically coupled to the second coil when the second coil approaches the third coil, wherein the secondary cell is charged via magnetic coupling between first/second coils when charging the secondary cell by the first power supply, and the secondary cell is charged via magnetic coupling between the third coil and second coils when charging the secondary cell by the second power supply.

Growing community of inventors

Tokyo, Japan

Satoshi Asano