Patent application number | Description | Published |
20110057568 | Light Adjustment Circuit For Alternating-Current Light Emitting Diodes (AC-LED's) - A light adjustment circuit for alternating-current light emitting diodes (AC-LED's) connected to an AC power supply and a plurality of AC-LED's comprises: a light adjustment unit, being capable of modulating AC power from the AC power supply while providing the plurality of AC-LED's with the modulated AC power; and a pulse width modulation (PWM) control circuit, being capable of modulating an external voltage signal in correspondence to variation in input AC power to enable each of the AC-LED's to achieve a predetermined brightness; wherein the AC-LED's are turned off by modulating the external voltage signal to prevent the AC-LED's from being burnt out when the input AC power is too high. | 03-10-2011 |
20130082666 | BUCK POWER FACTOR CORRECTION SYSTEM - The invention disclosed buck power factor correction system. The system includes: a first storing device, for storing and discharging energy; a first converter device, coupled to the first storing device, for transferring and converting energy; a second storing device, coupled to the first storing device, for storing and discharging energy; and a second converter device, coupled to the second storing device, for transferring and converting energy. | 04-04-2013 |
20130169242 | ACTIVE BUCK POWER FACTOR CORRECTION DEVICE - 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. | 07-04-2013 |
20140056046 | PASSIVE POWER FACTOR CORRECTION CIRCUIT, ELECTRONIC DEVICE APPLYING THE SAME AND OPERATION METHODS THEREOF - A passive power factor correction circuit includes: a DC capacitor and an input capacitor, coupled to a rectifying circuit and charged by a DC voltage from the rectifying circuit; an output capacitor, coupled to a load; first diode and a second diode, coupled to the input capacitor and the output capacitor; and an inductor, coupled to the load, the input capacitor and the output capacitor. Charging into and discharging from the DC capacitor are completed within a half cycle of an input AC voltage. | 02-27-2014 |
20140132231 | DC Conversion Circuit - A DC conversion circuit in the disclosure includes a buck-boost converter and a resonant stage circuit. The buck-boost converter has two input ends, a negative output end and a positive output end. The buck-boost converter receives a first DC signal via its two input ends, and outputs a second DC signal via its two output ends. The resonant stage circuit has two input ends and two output ends. The resonant stage circuit receives the second DC signal via its two input ends, converts the second DC signal into energy for power charging, and outputs the energy to a load via its two output ends. Then, the resonant stage circuit converts the energy, which is used for power charging, to form a negative voltage by a resonance effect, and outputs the energy to the load via its two output ends. | 05-15-2014 |
20140139128 | DIRECT CURRENT CONVERSION CIRCUIT - A direct current (DC) conversion circuit suitable for driving a load comprises a buck-boost converter, a resonant stage circuit and an output stage circuit. The buck-boost converter has two input ends receiving a first DC signal, and two output ends outputting a second DC signal. The resonant stage circuit has two input ends receiving the second DC signal. The resonant stage circuit converts the second DC signal to energy and further converts the energy to a negative voltage by a resonance effect. The resonant stage circuit has two input ends outputting the energy. The output stage circuit has two input ends receiving the energy to store the energy, and two output ends outputting energy to the load. | 05-22-2014 |