Rohm Co., Ltd.

Kionix, Inc.

Yo Yamashiro

Yuki Oishi

Richard A Deken

Shinichi Saitoh

Brian Thomas Samuelson

Hiroki Yano

Richard Alan Deken

The present disclosure provides an oscillator circuit. The oscillator circuit includes: a plurality of multi-stage inverters, connected in a ring shape to form a loop path; a capacitor, connected in series on the loop path; a charging/discharging control circuit, configured to charge/discharge the capacitor by pulse-driving a voltage level at a first end of the capacitor according to an output of any one of the multi-stage inverters; and a bias current generating circuit, configured to supply bias currents to each of the multi-stage inverters and the charging/discharging control circuit.

Oscillator circuit

Accelerometers are described herein that have RMS outputs. For instance, an example accelerometer may include a MEMS device and an ASIC. The MEMS device includes a structure having an attribute that changes in response to acceleration of an object. The ASIC determines acceleration of the object based at least in part on changes in the attribute. The ASIC includes analog circuitry, an ADC, and firmware. The analog circuitry measures the changes in the attribute and generates analog signals that represent the changes. The ADC converts the analog signals to digital signals. The firmware includes RMS firmware. The RMS firmware performs an RMS calculation on a representation of the digital signals to provide an RMS value that represents an amount of the acceleration of the object.

Accelerometer having a root-mean-square (RMS) output

An electrostatic capacitive sensor includes a plurality of transmitter electrodes, a plurality of receiver electrodes, and a control circuit. Further, the control circuit includes: a transmitter circuit configured to apply a periodical transmission signal to each of the plurality of transmitter electrodes; and a receiver circuit configured to generate, based on a reception signal generated in each of the plurality of receiver electrodes in response to the transmission signal, a detection signal indicating a change in electrostatic capacitance formed at each of intersections of the plurality of transmitter electrodes and the plurality of receiver electrodes, wherein the transmitter circuit is configured to switch between a first mode where the transmission signal is sequentially applied to the plurality of transmitter electrodes and a second mode where the plurality of transmitter electrodes are grouped and the same transmission signal is applied to a plurality of transmitter electrodes belonging to the same group.

Control circuit of electrostatic capacitive sensor and electronic device using the same

An electrostatic capacitive sensor includes a plurality of transmitter electrodes, a plurality of receiver electrodes, and a control circuit. The control circuit includes: a transmitter circuit configured to apply a periodical transmission signal to each of the plurality of transmitter electrodes; and a receiver circuit configured to generate, based on a reception signal generated in each of the plurality of receiver electrodes in response to the transmission signal, a detection signal indicating a change in electrostatic capacitance formed at each of intersections of the plurality of transmitter electrodes and the plurality of receiver electrodes, wherein the transmitter circuit and the receiver circuit are configured to switch between a first mode and a second mode, in the first mode, the transmission/reception signal is sequentially applied/monitored and in the second mode, the plurality of transmitter/receiver electrodes are grouped so that the same signal is applied to the same group.

Control circuit of mutual capacitance type electrostatic capacitive sensor and electronic device using the same

A charge pump circuit is provided. A voltage/current conversion circuit compares a feedback voltage that corresponds to the output voltage of the charge pump circuit with a predetermined reference voltage, and generates a bias current that corresponds to the difference therebetween. An oscillator oscillates at a frequency that corresponds to the bias current. A buffer is biased by the bias current, and supplies a gate clock to the charge pump circuit based upon a clock signal output from the oscillator, thereby driving the charge pump circuit.

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Kyoto, Japan

Yo Yamashiro