Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: Disclosed is an energy storage system provided with a wired and wireless energy transfer function. The energy storage system includes: an energy input unit to which energy generated from a plurality of energy sources is input; an energy input control unit for selecting one energy source from among the plurality of energy sources, and transferring energy of the selected energy source through operation in a wired operation mode or a wireless operation mode; a wireless energy transmitting/receiving unit for wirelessly transmitting/receiving the energy of the selected energy source during the operation in the wireless operation mode of the energy input control unit; an energy storage/control unit for storing the energy of the selected energy source; an energy output unit for consuming the energy stored in the energy storage/control unit; and an energy output control unit for distributing the energy stored in the energy storage/control unit to the energy output unit.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: Provided is a capacitor-type sensor read-out circuit. The capacitor-type sensor read-out circuit includes: a signal conversion unit outputting a sensor signal inputted from a sensor; a voltage booster generating a bias voltage; and a capacitor-type signal coupling circuit receiving the sensor signal as a feedback, mixing the received sensor signal with the bias voltage, and outputting the mixed signal.

Abstract: 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.

Abstract: 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.

Abstract: 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

Abstract: 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.

Abstract: Disclosed is a DC-DC converter, including: a switch unit configured to generate output voltage for driving a load; an output voltage monitoring unit including a reference voltage generator generating reference voltage and a reference voltage capacitor maintaining the reference voltage when power of the reference voltage generator is interrupted and configured to generate a signal for setting the output voltage as the reference voltage; a switch controlling unit configured to control the switch unit by being operated in a pulse width modulation (PWM) mode or a pulse frequency modulation (PFM) mode by using the signal of the output voltage monitoring unit; and a mode determining and power interrupting unit configured to set an operating mode of the switch controlling unit as the PWM mode or the PFM mode according to a magnitude of the load and interrupt power of the reference voltage generator when operated in the PFM mode.

Abstract: Disclosed is a DC-DC converter including: a switch unit controlling a flow of a current based on a buck-boost topology; a short circuit unit short circuited or opened according to an external setting to change a topology of the switch unit; an inductor storing a current induced by the switch unit; a topology selecting unit selecting a topology in response to an external input signal and generating a signal corresponding to the selected topology; a pulse width modulating unit generating a signal for determining an operation time of the switch unit; a reverse flow detecting unit detecting a reverse flow of a current flowing through the switch unit to generate a signal; and a switch control unit controlling the switch unit in response to signals of the topology selecting unit, the pulse width modulating unit and the reverse flow detecting unit.

Abstract: 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.