Abstract: A DC-AC converter is provided. The DC-AC converter includes a time-varying DC power generating circuit, an AC power generating circuit and a transmission capacitor. The time-varying DC power generating circuit is controlled by a pulse width modulation (PWM) signal to transform a DC source into a time-varying DC power. With reference to the time-varying DC power, the AC power generating circuit is controlled by a first polarity switching and a second polarity switching signal to generate an AC power. The transmission capacitor, coupled to the time-varying DC power generating circuit and the AC power generating circuit, transmits the time-varying DC power from the time-varying DC generating circuit to the AC power generating circuit.

Abstract: The present invention relates to a solar-powered wireless communication module with daylight intensity measurement, which comprises: a solar cell module, capable of converting solar energy into electricity; a Microcontroller Unit (MCU), coupled to the solar cell module for detecting and outputting values regarding the voltage and the current of the electricity converted from the solar cell module; and a wireless communication unit, powered by the electricity from the solar cell module and coupled to the MCU for transmitting values outputted from the MCU to a control end.

Abstract: The present disclose relates to a power active buck power factor correction device, comprising: a AC source; a rectifying device coupled to the AC source for receiving and rectifying the AC source so as to generate an input voltage; a first converting device coupled to the assistance device for receiving, transmitting, converting and storing energy; a load coupled to the first converting device; and an assistance device coupled to the first converting device for generating an assistance voltage. Specifically, the polarity of the assistance voltage is same with the input voltage, but is contrary to an output voltage, so that the first converting device may continue to work and receive an input current under the input voltage is smaller than the output voltage while the discontinue time of the input current is getting shorter so as to obtain the perfected power factor correction effect.

Abstract: A DC-AC converter is provided. The DC-AC converter includes a time-varying DC power generating circuit, an AC power generating circuit and a transmission capacitor. The time-varying DC power generating circuit is controlled by a pulse width modulation (PWM) signal to transform a DC source into a time-varying DC power. With reference to the time-varying DC power, the AC power generating circuit is controlled by a first polarity switching and a second polarity switching signal to generate an AC power. The transmission capacitor, coupled to the time-varying DC power generating circuit and the AC power generating circuit, transmits the time-varying DC power from the time-varying DC generating circuit to the AC power generating circuit.

Abstract: The present invention relates to a tri-state delay-typed phase lock loop, which comprises: a phase and frequency detector, a mode detector, a mode selector, a first sampling delay unit, a plurality of counters, a second sampling delay unit, and a phase and frequency calculator. The phase and frequency of the input reference signal can be determined automatically by the phase lock loop, and the output synchronization signal can be generated such that the frequency and the phase of the output synchronization signal are identical to those of the input reference signal.

Abstract: The present invention relates to a tri-state delay-typed phase lock loop, which comprises: a phase and frequency detector, a mode detector, a mode selector, a first sampling delay unit, a plurality of counters, a second sampling delay unit, and a phase and frequency calculator. The phase and frequency of the input reference signal can be determined automatically by the phase lock loop, and the output synchronization signal can be generated such that the frequency and the phase of the output synchronization signal are identical to those of the input reference signal.

Abstract: The present invention relates to a solar-powered wireless communication module with daylight intensity measurement, which comprises: a solar cell module, capable of converting solar energy into electricity; a Microcontroller Unit (MCU), coupled to the solar cell module for detecting and outputting values regarding the voltage and the current of the electricity converted from the solar cell module; and a wireless communication unit, powered by the electricity from the solar cell module and coupled to the MCU for transmitting values outputted from the MCU to a control end.