Omron Tateisi Electronics Co.

Murata Manufacturing Co., Ltd.

Omron Corporation

Omrom Corporation

Hidetoshi Matsumoto

Masahiro Ito

Kiichiro Takenaka

Masao Kondo

Toshiyuki Kobayashi

Kazuo Sasaki

Hirofumi Endo

Masatsugu Miura

Yuuma Noguchi

Yutaka Nozaki

Koji Ohmori

Takao Ohta

Daiji Nagashima

Taneji Ohoka

Keisuke Ishibashi

Hidehiro Fukumoto

Hiroaki Nakanishi

Kuniharu Shibata

A radio frequency signal having a constant amplitude is modulated by a digital modulation signal and a radio frequency input signal whose amplitude changes stepwise is generated. The radio frequency input signal is input into a power amplifier that is an evaluation target. A period in which an amplitude of the radio frequency input signal is constant is defined as a measurement period and an output signal of the power amplifier is measured in each of measurement periods in which amplitudes of the radio frequency input signal are different from each other.

Power amplifier evaluation method and measurement system

A power amplifier module includes an amplifier transistor and a bias circuit. A first power supply voltage based on a first operation mode or a second power supply voltage based on a second operation mode is supplied to the amplifier transistor. The amplifier transistor receives a first signal and outputs a second signal obtained by amplifying the first signal. The bias circuit supplies a bias current to the amplifier transistor. The bias circuit includes first and second resistors and first and second transistors. The first transistor is connected in series with the first resistor and is turned ON by a first bias control voltage which is supplied when the first operation mode is used. The second transistor is connected in series with the second resistor and is turned ON by a second bias control voltage which is supplied when the second operation mode is used.

Power amplifier module

In a distance measuring apparatus for optically detecting a distance to an object by using a triangulation method, two signals which are obtained from a position sensitive device are added and it is detected that the result of the addition has exceeded a predetermined threshold level. On the other hand, it is assumed that a signal waveform to drive a light emitting device is a signal whose level increases with an elapse of time. When the addition result exceeds the threshold level, the level of the drive signal is held constant. At this time, by dividing a signal obtained from the position sensitive device by the signal indicative of the addition result, a signal relating to the distance to the object is obtained.

Optical distance measuring apparatus and method using light projection

The timer circuit according to this invention has a first circuit block to which a source voltage is applied at all times and which includes a memory circuit which is set when an input signal is applied thereto. The timer circuit also has a reference voltage circuit which outputs a reference voltage when the memory circuit is set and which ceases to output the reference voltage when the memory circuit is reset, an oscillation circuit which outputs a train of pulse signals in a predetermined cycle, and a counter which begins to count the train of pulse signals after the reference voltage is outputted. The timer circuit further includes a second circuit block which includes a signal processing circuit which outputs a timer signal while the counter is counting. A reference voltage is supplied from the reference voltage circuit to the components of the second circuit block while the memory circuit remains set and the memory circuit is reset in response to a time-out signal from the counter.

Timer circuit

A sensor according to this invention comprises an oscillation circuit including an LC resonant circuit, wherein a detection signal is prohibited upon arrival of an external radio wave.

Metal detector protected from malfunction caused by radio waves

The present invention is directed to a motor rotation speed controlling apparatus including a comparator, a detecting circuit for detecting a feedback signal of a motor, a motor driving transistor, and a circuit for changing the level of a constant voltage fed to the comparator. The comparator compares a saw-tooth voltage with a constant voltage and outputs a signal which has a duty cycle corresponding to the result of the comparison. The motor driving transistor drives the motor in response to the output signal from the comparator. To change the duty cycle of the output signal from the comparator, a circuit is used that changes the level of the constant voltage in response to a feedback signal detected by the detecting circuit.

Motor rotation speed controlling apparatus

A measuring circuit device comprising a measuring circuit, a display associated with the measuring circuit for displaying data generated by the measuring circuit, a display test circuit for testing the display, a performance test circuit associated with the measuring circuit for actuating the measuring circuit to display predetermined reference measured data by the display, a switch for initiating operation of the device, a switch circuit which upon actuation of the switch actuates the display test circuit and the performance test circuit, and which in a predetermined time period, initiates a measuring operation by the measuring circuit.

Measuring circuit device

Growing community of inventors

Kyoto, Japan

Hidetoshi Matsumoto