Abstract: An LED illuminant driving circuit and an automatic brightness compensation method thereof are provided herein. The automatic brightness compensation method includes: providing a target value; detecting an operation period of a pulse of an output of the LED illuminant driving circuit, the pulse is adapted to an LED illuminant for making the light emitting; deciding a peak value according to the target value and the operation period; and setting a peak level of the pulse according to the peak value. The LED illuminant driving circuit and the automatic brightness compensation method thereof provides a stable average current/voltage to the LED illuminant and avoids brightness variations of the light emitting.

Abstract: A current generator, including a chopper stabilization operational amplifier, a transistor, and an impedance unit is provided. The chopper stabilization operational amplifier includes a first input terminal, a second input terminal, and an output terminal. The transistor includes a gate coupled to the output terminal of the chopper stabilization operational amplifier, a first source/drain coupled to the first input terminal of the chopper stabilization operational amplifier, and a second source/drain serving as a current output terminal of the current generator. The impedance unit includes a first terminal coupled to the first source/drain of the transistor, and a second terminal coupled to a first voltage.

Abstract: A generator for generating reference voltage and reference current includes a reference voltage generating circuit for generating a first voltage and a second voltage, which are in combination to produce a reference voltage. The first voltage and the second voltage are respectively having a first-direction response variation and a second-direction response variation, according to a temperature variation. A voltage-to-current inverting circuit is coupled to the reference voltage generating circuit for generating a first current, which has the first-direction response variation as the temperature variation, according to the first voltage. An adding circuit is coupled to the reference voltage generating circuit and the voltage-to-current inverting circuit to obtain a second current corresponding to the second voltage from the reference voltage generating circuit. The first current and the second current are added to have a reference current.

Abstract: An over current protection circuit and a power converter using the same. The over current protection circuit includes a soft start cell and an operational amplifier. The soft start cell outputs a soft start signal according to a direct current (DC) level, and the soft start signal increases progressively to the DC level in a soft start interval. The operational amplifier outputs an over current signal to a feedback control circuit according to the soft start signal and an inductance current of a switching converter so that a duty cycle of a driving signal from the feedback control circuit increases progressively in the soft start interval.

Abstract: A power circuit and a charge pumping circuit add one control switch of small size to control a power transistor, and save one switch of large area and one capacitor of large area as compared with a conventional power circuit and a conventional charge pumping circuit. The power circuit includes a power processing circuit, a linear voltage-regulating switch, and a capacitor. The linear voltage-regulating switch includes a power transistor and a control switch. The control switch has a first end coupled to a gate of the power transistor and a second end coupled to one of a drain and a source of the power transistor. When the control switch is “on”, the power transistor is “off”. When the control switch is “off”, the voltage on the drain of the power transistor is maintained at a predetermined value by the linear voltage-regulating switch.

Abstract: A charge pump circuit is provided. The charge pump circuit includes a pump unit, first through sixth switches, a fly capacitor and an output capacitor. In a first period, an input voltage and a first voltage charge at least one internal capacitor of the pump unit via a first terminal and a second terminal of the pump unit. In the second period, the internal capacitor of the pump unit provides charges to the fly capacitor via the second switch and generates a first output voltage. In the third period, the fly capacitor supplies the charges to the output capacitor via the fourth switch to generate a second output voltage.

Abstract: A radio frequency (RF) positioning system for positioning an RF device on a surface is provided. The RF positioning system utilizes the property of the RF device generating a response signal upon receiving an RF signal to perform positioning. The RF positioning system includes an antenna set, a switch unit, an RF module and micro-controller unit (MCU). The antenna set has a plurality of antennas in different sizes. The RF module is coupled to the switch unit. The MCU, coupled to the switch unit and the RF module, controls the switch unit to select one antenna from the antenna set and controls the RF module to generate the RF signal. The MCU further estimates a distance between the RF device and the RF positioning system according to whether the RF positioning system receives the response signal through the selected antenna.

Abstract: A power conversion system and a power conversion method thereof. The power conversion system includes a driving unit, a control unit, a first direct current (DC) power supply circuit and a second DC power supply circuit. The control unit controls the driving unit to drive a load. The first DC power supply circuit converts an alternating current (AC) power into a first DC power outputted to the driving unit, and the second DC power supply circuit converts the AC power into a second DC power outputted to the control unit.

Abstract: A light adjusting device for a light emitting diode includes a switch, a detecting unit and an illumination adjusting unit. The switch is coupled to a power terminal, which is utilized for providing power for the light emitting diode. The detecting unit is coupled to the switch, and is utilized for determining a status of the switch, so as to generate a detecting result. The illumination adjusting unit is coupled to the detecting unit, and is utilized for adjusting illumination of the light emitting diode according to the detecting result.

Abstract: A light source apparatus and a light source adjusting module are provided. The light source apparatus includes a power supply, a phase modulator, an electrical transformer, a light source adjusting module and a light-emitting device. The power supply provides a first AC voltage signal. The phase modulator receives the first AC voltage signal and adjusts a conducting phase of the first AC voltage signal to generate a modulated AC voltage signal. The electrical transformer transforms the modulated AC voltage signal to generate a second AC voltage signal. The light adjusting module generates a luminance adjusting signal according to a state of the second AC voltage signal. The light-emitting device receives the luminance adjusting signal to generate a corresponding light source.

Abstract: A current generator, including a chopper stabilization operational amplifier, a transistor, and an impedance unit is provided. The chopper stabilization operational amplifier includes a first input terminal, a second input terminal, and an output terminal. The transistor includes a gate coupled to the output terminal of the chopper stabilization operational amplifier, a first source/drain coupled to the first input terminal of the chopper stabilization operational amplifier, and a second source/drain serving as a current output terminal of the current generator. The impedance unit includes a first terminal coupled to the first source/drain of the transistor, and a second terminal coupled to a first voltage.

Abstract: A multi-step charge pump having a power input terminal and a power output terminal is provided. The multi-step charge pump includes a plurality of capacitors, wherein each of the capacitors has a capacitance. A plurality of switching devices is connected among the capacitors, the power input terminal and the power output terminal. A switch-controlling unit controls the on/off states of the switches, wherein a charging-phase circuit corresponding to a pumping level is formed to charge the capacitors and an output-phase circuit is formed to output a voltage from the power output terminal. At least one of the capacitors herein is changeably selected as a voltage-regulating capacitor.

Abstract: A voltage regulator and a voltage regulating method thereof and a voltage generator using the voltage regulator are disclosed by the present invention. The voltage regulator of the present invention uses a first switching unit and a second switching unit to respectively provide an operational transconductance amplifier (OTA) with different closed-loop feedback paths during a first period and a second period. In this way, an auto-zeroing unit is able to exactly store an input offset voltage presented between the inverting input terminal and the non-inverting input terminal of the OTA.

Abstract: The present invention relates to an electronic apparatus and an auto wake-up circuit thereof. The electronic apparatus comprises a main module for performing a main function of the electronic apparatus and generating a first control signal when the electronic apparatus enters a sleep mode; an auxiliary module, coupled to the main module, for performing an auxiliary function of the electronic apparatus and generating a second control signal; and a wake-up circuit module, coupled to the main module and the auxiliary module, for generating a third control signal based on the first control signal and the second control signal. The auxiliary module maintains the auxiliary function based on the third control signal while the electronic apparatus is in the sleep mode.

Abstract: An apparatus of dynamic feedback control charge pump is provided. The apparatus of dynamic feedback control charge pump receives an input voltage through a voltage regulator. The voltage regulator regulates the input voltage to a base voltage according to a control signal. The charge pump receives the base voltage and provides multiple of the base voltage to an output voltage. A feedback unit provides the control signal to the voltage regulator according to the output voltage. Therefore, the apparatus of dynamic feedback control charge pump can reduce the output voltage ripple and improve the output efficiency of the charge pump.

Abstract: A wireless communication method utilizing a wireless communication apparatus is provided. The method includes: providing an antenna unit being used by both a first wireless communication circuit and a second wireless communication circuit, using the first wireless communication circuit for RFID communication via the antenna unit in a first mode, and utilizing the second wireless communication circuit for RFID communication via the antenna unit in a second mode.

Abstract: A charge pump circuit is provided. The charge pump circuit includes a pump unit, first through sixth switches, a fly capacitor and an output capacitor. In a first period, an input voltage and a first voltage charge at least one internal capacitor of the pump unit via a first terminal and a second terminal of the pump unit. In the second period, the internal capacitor of the pump unit provides charges to the fly capacitor via the second switch and generates a first output voltage. In the third period, the fly capacitor supplies the charges to the output capacitor via the fourth switch to generate a second output voltage.

Abstract: A sample-and-hold apparatus and an operating method thereof are provided. The sample-and-hold apparatus includes a sampling amplifier, a transistor, a first switch, a second switch, a sampling capacitor, and a drain-charge unit. A first input terminal of the sampling amplifier receives an input signal. A first-terminal of the transistor is coupled to a first voltage. The first switch is coupled between an output terminal of the sampling amplifier and a gate of the transistor. The first and second terminals of the second switch are coupled to a second terminal of the transistor and a second input terminal of the sampling amplifier, respectively. The first and second terminals of the sampling capacitor are coupled to the gate of the transistor and a reference voltage. The drain-charge unit for draining/providing charges has first and second terminals coupled to the second terminal of the second switch and a second voltage, respectively.

Abstract: A test system for testing operability of integrated circuits includes: a first IC, for modulating a first signal to generate a first modulated signal and transmitting the first modulated signal, and for receiving a second modulated signal and demodulating the second modulated signal to generate a second signal; a first loop antenna, coupled to the first IC, for receiving the first modulated signal and sending the first modulated signal back to the first IC as the second modulated signal; and a tester circuit coupled to the first IC, for generating the first signal to the first IC, receiving the second signal from the first IC, and comparing the first signal and the second signal to determine the operability of the first IC.

Abstract: An electronic device and related method for enhancing convenience of a computer system includes a memory unit for storing a plurality of boot-up configuration files and a plurality of human characteristic signals corresponding to the plurality of boot-up configuration files, a human characteristic reception unit for receiving a human characteristic, and a logic unit coupled to a power switch, the memory unit, and the human characteristic reception unit, for comparing the human characteristic received by the human characteristic reception unit and the plurality of human characteristic signals stored in the memory unit for generating a comparison result when the power switch is turned on, and performing a boot-up procedure to turn on the computer system according to the comparison result.