Electronics and Telecommunications Research Institute

Jong-Kee Kwon

Young-Deuk Jeon

Young Kyun Cho

Jaewon Nam

Yil Suk Yang

Tae Moon Roh

Woo Seok Yang

Min-Hyung Cho

Yi-Gyeong Kim

Jongdae Kim

Hui Dong Lee

Kyung-Soo Kim

Ook Kim

Won-Chul Song

Jong-Ryul Lee

Chang-Jun Oh

Seok Ju Yun

Sang Kyun Lee

Chang Han Je

Kwi Dong Kim

Bong Chan Kim

Jaewoo Lee

Young Sam Park

Moon Gyu Jang

Taehyoung Zyung

Hee-Bum Jung

Sewan Heo

Younghoon Hyun

Sang-Hyun Cho

Kwi-Dong Kim

Gyu-Dong Kim

A method of fabricating a flexible piezoelectric energy harvesting device is provided. The method includes forming a piezoelectric layer to include a plurality of first piezoelectric lines spaced apart from each other in one direction and a plurality of second piezoelectric lines respectively filling spaces between the first piezoelectric lines, then placing the piezoelectric layer on a first flexible electrode substrate to come in direct contact with the first flexible electrode, and forming a second flexible electrode substrate on the piezoelectric layer.

Method of fabricating piezoelectric energy harvesting device

A motor control device including a preprocessing portion calculating a counter electromotive force using an analog operation is provided. The motor control device may include an offset compensation portion and a counter electromotive force measuring portion. The offset compensation portion receives a three-phase current signal from the motor and compensates an offset of the three-phase current signal. The counter electromotive force measuring portion receives the compensated current signal and a three-phase voltage signal from the motor and calculates the received current signal and the received voltage signal using an analog operation to provide the calculated result.

Motor control device and method of controlling the same

A flexible piezoelectric energy harvesting device includes a first flexible electrode substrate, a piezoelectric layer disposed on the first flexible electrode substrate, and a second flexible electrode substrate disposed on the piezoelectric layer. The piezoelectric layer may include a plurality of first piezoelectric lines spaced apart from each other in one direction and a plurality of second piezoelectric lines respectively filling spaces between the first piezoelectric lines.

Piezoelectric energy harvesting device and method of fabricating the same

Provided is a microphone. The microphone includes a substrate including an acoustic chamber, a lower backplate disposed on the substrate, a diaphragm spaced apart from the lower backplate on the lower backplate, the diaphragm having a diaphragm hole passing therethrough, a connection unit disposed on the lower backplate to extend through the diaphragm hole, and an upper backplate disposed on the connection unit, the upper backplate being spaced apart from the diaphragm. Thus, the microphone may be improved in sensitivity and reliability.

Microphone

Provided are an acoustic sensor and a method of manufacturing the same. The acoustic sensor includes a substrate including an acoustic chamber, a first hole, and a second hole, penetrating the substrate, a lower electrode pad extended onto a top surface of the substrate while covering a sidewall of the first hole, a diaphragm pad extended onto the top surface of the substrate while covering a sidewall of the second hole, a lower electrode provided on the acoustic chamber and connected to the lower electrode pad, and a diaphragm above the lower electrode while being separated from the lower electrode and connected to the diaphragm pad.

Acoustic sensor

Provided is a wheel speed sensor interface. The wheel speed sensor interface includes: a speed pulse detection circuit configured to receive a plurality of sensor signals including wheel speed information of a vehicle, detect a plurality of speed pulses on the basis of the plurality of the received sensor signals, and transmit the plurality of the detected speed pulses to an external device; and a comparison speed detection circuit configured to generate a plurality of counting values by counting each of the detected speed pulses, generate comparison speed information by multiplexing the plurality of the generated counting values through a time division method, and transmit the generated comparison speed information to the external device.

Wheel speed sensor interface, operation method thereof, and electronic control system including the same

Provided is a thermoelectric device including two legs having a rough side surface and a smooth side surface facing each other. Phonons may be scattered by the rough side surface, thereby decreasing thermal conductivity of the device. Flowing paths for electrons and phonons may become different form each other, because of a magnetic field induced by an electric current passing through the legs. The smooth side surface may be used for the flowing path of electrons. As a result, in the thermoelectric device, thermal conductivity can be reduced and electric conductivity can be maintained.

Thermoelectric devices

Disclosed is a sound detecting circuit which includes a sensing unit configured to generate an AC signal in response to a sound pressure level of a sound signal; an amplification unit configured to amplify the AC signal; and a bias voltage generating unit configured to generate a bias voltage to be provided to the amplification unit. The bias voltage generating unit comprises a current source configured to provide a power current; and a current-voltage converting circuit configured to convert the power current into the bias voltage and to reduce a noise due to the power current.

Sound detecting circuit and amplifier circuit thereof

The inventive concept discloses a new temperature sensor structure based on oscillator which is insensitive to a process change and improves an error rate of temperature output. The temperature sensor based on oscillator compares an oscillator circuit structure insensitive to a temperature change with an oscillator circuit structure having a frequency change in proportion to a temperature change to output a relative difference between the two oscillator circuit structures and thereby it is compensated itself. In the temperature sensor based on oscillator, a problem of performance reduction due to an external environment and a process deviation of temperature sensor is improved and an output distortion and temperature nonlinearity are effectively improved. Thus, since the temperature sensor based on oscillator has a structure of high performance, low power and low cost, it can be variously used in a detection equipment of temperature environment.

Process independent temperature sensor based on oscillator

Provided is a maximum power extraction devices including: a battery; a voltage control unit adjusting a size of a first power outputted from the battery according to a resistor selected from a plurality of resistors, and generating a compare signal according to a size difference between an operating voltage adjusting the size of the first power depending on the selected resistor and a reference voltage; a switching unit connected between the battery and a load and adjusting a size of the operating voltage according to a size difference of the compare signal in response to first and second switching control signals; a switching control unit generating the first and second switching control signals to allow a size between the operating voltage according to the compare signal and the reference voltage to be within an error range; and a maximum power control unit measuring the number of first operations obtained by counting the occurrence number of the first or second switching control signals for a predetermined time, when the compare signal is within the error range.

Maximum power extraction device

An MEMS microphone is provided which includes a reference voltage/current generator configured to generate a DC reference voltage and a reference current; a first noise filter configured to remove a noise of the DC reference voltage; a voltage booster configured to generate a sensor bias voltage using the DC reference voltage the noise of which is removed; a microphone sensor configured to receive the sensor bias voltage and to generate an output value based on a variation in a sound pressure; a bias circuit configured to receive the reference current to generate a bias voltage; and a signal amplification unit configured to receive the bias voltage and the output value of the microphone sensor to amplify the output value. The first noise filter comprises an impedance circuit; a capacitor circuit connected to a output node of the impedance circuit; and a switch connected to both ends of the impedance circuit.

MEMS microphone using noise filter

Provided is a sensorless BLDC motor system. The sensorless BLDC motor system includes a BLDC motor, a comparator, a motor controller, a three-phase inverter, and a mode selector. The BLDC motor includes first to third coils. The comparator compares a voltage of a specific coil of the first to third coils with a neutral-point voltage to output the compared result. The voltage of the specific coil becomes equal to the neutral-point voltage and a specific time elapses, and then the motor controller generates first and second coil control signals based on the compared result. The three-phase inverter supplies a source voltage or ground voltage to the specific coil, or floats the specific coil, in response to the first and second coil control signals. The mode selector selects a driving mode of the BLDC motor by adjusting the specific time.

Sensorless BLDC motor systems and driving methods of sensorless BLDC motor

A successive approximation register analog-to-digital converter is provided which includes first and second capacitor arrays configured to generate first and second level voltages, respectively; a comparator configured to compare the first and second level voltages to output a comparison signal; SAR logic configured to generate a digital signal in response to the comparison signal; and a variable common mode selector configured to compare a first analog input voltage and a common mode voltage and to supply one of the first analog input voltage and the common mode voltage to top plates of the first and second capacitor arrays according to a comparison result.

Successive approximation register analog-to-digital converter

The present inventive concept relates to an analog-digital converter. The analog-digital converter includes a clock generating unit generating a clock signal; a clock delay adjusting unit outputting one of a first clock signal to a Kth clock signal according to a control signal; a capacitive digital-analog converting unit outputting a difference between the analog signal and a reference signal; a comparison unit judging whether an output of the capacitive digital-analog converting unit is 0, a positive number, or a negative number, in response to an output of the clock delay adjusting unit; and an SAR logic unit transferring an output of the comparison unit to the capacitive digital-analog converting unit in response to an output of the clock delay adjusting unit and performing a successive approximation operation to output the N-bit digital signal.

Analog-digital converter and converting method using clock delay

Disclosed is a bias circuit which includes a bias voltage generating part configured to generate a bias voltage using a reference current and a variable current; a reference current source part configured to provide the reference current to the bias voltage generating part; and a current adjusting part configured to provide the variable current to the bias voltage generating part and to adjust the amount of the variable current according to voltage levels of at least two input signals. The bias circuit prevents an increase in power consumption and improves a slew rate at the same time.

Growing community of inventors

Daejeon, South Korea

Jong-Kee Kwon