Denso Corporation

Nippondenso Co., Ltd.

Toshio Ikuta

Takamoto Watanabe

Noboru Endo

Yasutoshi Suzuki

Minekazu Sakai

Tsuyoshi Fukada

Yasuaki Makino

Seiya Ide

Nobukazu Oba

Shunji Mase

Tadashi Shibata

Masahiro Aratani

Seiichirou Otake

Noboru Endou

A dynamic quantity detection device includes a detection portion, a signal process portion, and an operation mode switch portion. The detection portion detects a dynamic quantity applied from an outside and generates a sensor signal in accordance with the dynamic quantity. The signal process portion processes the sensor signal from the detection portion to have a property suitable for an external device. When the sensor signal output from the detection portion is less than or equal to a predetermined threshold value, the operation mode switch portion sets an operation mode to a power save mode by stopping an operation of the signal process portion. When the sensor signal output from the detection portion is greater than the predetermined threshold value, the operation mode switch portion switches the operation mode to a normal mode by activating the signal process portion.

Dynamic quantity detection device

Physical quantity detection equipment includes a detector, an amplifier, an offset adjustment device, an addition device, and an output device. The detector outputs the first voltage corresponding to the detected physical quantity. The amplifier amplifies the first voltage. The offset adjustment device determines a measurement range of the amplified first voltage and outputs a second voltage corresponding to the determined measurement range. The addition device subtracts the second voltage from the amplified first voltage. The output device outputs the subtracted amplified first voltage and informs the determined measurement range. The equipment has only one sensing unit for detecting both a large and a fine change in physical quantity.

Physical quantity detection equipment

A sensing element detects a predetermined physical quantity and generates a sensor signal. A signal processing circuit processes the sensor signal and generates an output signal. A first memory circuit stores characteristics control data used for adjusting sensor output characteristics. An adjusting circuit performs an adjustment to equalize the sensor output to a target value based on the characteristics control data stored in the first memory circuit. A second memory circuit stores fine control data used in a fine adjustment performed to correct a deviation resulting after the adjustment based on the characteristics control data stored in said first memory circuit.

Sensing apparatus for detecting a physical quantity, including memory circuits storing characteristics adjusting data

An analog multiplexer is provided to time divisionally process a reference signal Sa obtained from a reference voltage generating circuit, a temperature signal St obtained from a temperature detecting bridge circuit, and a sensor signal Sd obtained from a pressure detecting bridge circuit. These signals Sa, St and Sd are converted into digital data through a common differential amplification circuit and a common A/D conversion circuit. A correction circuit calculates an applied pressure value based on the digital data produced from the A/D conversion circuit, as a value corrected with reference to the temperature signal St and the reference signal Sa.

Sensing apparatus including an A/D conversion circuit for detecting a physical quantity

An intentional offset value is set beforehand. The intentional offset value is larger than a sensing objective signal &ldquo;sig.&rdquo; A measuring device is provided for measuring the intentional offset value to obtain a measured intentional offset value &ldquo;a&rdquo; representing the quantity of the intentional offset value, and also for measuring a sum of the sensing objective signal &ldquo;sig&rdquo; and the intentional offset value to obtain a measured signal value &ldquo;b&rdquo; representing a summation of the quantity of the sensing objective signal and the quantity of the intentional offset value. A ratio (b/a) of the measured signal value to the measured intentional offset value is obtained. The obtained ratio is used as noise reducing data for reducing the noise involved in a sensor output.

Low-frequency noise removing method and a related CMOS sensing circuit

A semiconductor pressure detection device includes a diaphragm formed at a portion of a P- conductivity type semiconductor substrate having a reduced thickness. Gauge resistors are formed on the surface of an N- conductivity type semiconductor layer formed on the substrate. An N+ conductivity type diffusion layer is formed in the N- conductivity type semiconductor layer to fix the electric potential of the N- conductivity type layer. The first conductivity type area surrounds the diaphragm. Therefore, when the N- conductivity type area is supplied with electric potential, the potential gradient in the N- conductivity type layer is small. Thus, the leakage current which flows to a pn junction between the gauge resistors and the N- conductivity type area is reduced.

Semiconductor device and method for producing the same

An improved on-chip type filter for filtrating electromagnetic noise is disclosed. Within a sensor chip are provided processing and amplifying circuits, a ground pad, a power pad and an output pad. Also, within the sensor chip are disposed low pass filters between the power pad, the outpad and the circuits to filtrate electromagnetic noise. The lengths of aluminum wires connecting the power pad, the output pad and the low pass filters are shorter than the lengths of aluminum wires connecting the ground pad and the low pass filters. The aluminum wires connecting the power pad or the output pad and the low pass filters are uncrossed wires, which do not cross any other wires.

Semiconductor device that suppresses electromagnetic noise

A digital-to-analog converter includes an R-2R resistive ladder network having resistors connected in a ladder form in correspondence with a number of bits of a digital input signal. The R-2R resistive ladder network has an output terminal. A pair of positive and negative dc-power-supply terminals are connected to the R-2R resistive ladder network. Currents flowing between the R-2R resistive ladder network and one of the positive and negative dc-power-supply terminals are controlled in response to the bits of the digital input signal to generate an analog voltage signal at the output terminal of the R-2R resistive ladder network. The analog voltage signal depends on the digital input signal. A first resistor and a second resistor located outside the R-2R resistive ladder network are connected in series between the positive and negative dc-power-supply terminals. A third resistor located outside the R-2R resistive ladder network is connected between the output terminal of the R-2R resistive ladder network and the second resistor located outside the R-2R resistive ladder network. A conversion output terminal is connected to a junction between the second and third resistors located outside the R-2R resistive ladder network.

Digital-to-analog converter and sensor-characteristic adjustment circuit

A semiconductor sensor device which has a decreased number of terminals, which is cheaply and compactly constructed and which contains a trimming circuit. A power source voltage and a clock signal having a voltage level greater than the power source voltage are input to a terminal 31. A logic circuit 22 starts operating at one voltage level of a terminal 33 and temporarily stores serial digital signals that are input through a terminal 32 in response to clock signals as parallel trimming data. A gauge circuit 11 operates based on the stored trimming data, and the gauge output is sent to the terminal 32. With another voltage level from the terminal 33, the logic circuit 22 trims a fuse memory circuit 23 based on the stored trimming data. At a further voltage level from the terminal 33, the gauge circuit 11 is operated based on the data in the fuse memory circuit 23 that is trimmed, and an output signal thereof is sent to the terminal 32.

Growing community of inventors

Handa, Japan

Toshio Ikuta