THREE-PHASE PWM-SIGNAL-GENERATING APPARATUS
Issued June 16, 2009
United States Patent 7,548,443
Arisawa, et al
An apparatus for generating a three-phase pulse-width-modulation signal for a three-phase voltage inverter employing a semiconductor switching element includes a generating unit that generates the three-phase pulse-width-modulation signal based on at least one combination of three basic voltage vectors and at least a zero vector.
Inventors: Arisawa; Koichi (Tokyo, JP), Sakanobe; Kazunori (Tokyo, JP), Shinomoto; Yosuke (Tokyo, JP), Yabe; Masaaki (Tokyo, JP)
Assignee: Mitsubishi Denki Kabushiki Kaisha (Chiyoda-ku, Tokyo, JP)
Appl. No.: 10/580,849
Filed: August 10, 2005
PCT Filed: August 10, 2005
UNIVERSAL AC ADAPTER
Issued June 16, 2009
United States Patent 7,548,441
Vinciarelli
A method and apparatus for adaptively configuring an array of voltage transformation modules is disclosed. The aggregate voltage-transformation ratio of the adaptive array is adjusted to digitally regulate the output voltage for a wide range of input voltages. An integrated adaptive array having a plurality of input cells, a plurality of output cells, or a plurality of both is also disclosed. The input and output cells may be adaptively configured to provide an adjustable-transformer turns ratio for the adaptive array or, in the case of an integrated VTM, an adjustable voltage transformation ratio for the integrated VTM. A controller is used to configure the cells and provide digital regulation of the output. A converter having input cells configured as a complementary pair, which are switched out of phase, reduces common-mode current and noise. Series-connected input cells are used for reducing primary-switch voltage ratings in a converter and enabling increased operating frequency or efficiency. An off-line auto-ranging power-supply topology is disclosed. An auto-ranging converter module (ACM) includes two or more input cells magnetically coupled to an output cell providing auto-ranging, isolation, and voltage transformation. The ACM converts a rectified line voltage to a low dc bus voltage. The topology allows regulation and power-factor correction to be provided at a low voltage, increasing energy density and efficiency and reducing cost. A fully integrated PCM may also include a hold-up circuit, a dc input, and a power regulator with or without power-factor correction. A PCM with PFC may combine the hold-up and smoothing capacitors for further increases in power density. A universal ac adapter architecture is shown using a unipolar bus to distribute power to one or a plurality of stationary or mobile electronic devices.
Inventors: Vinciarelli; Patrizio (Boston, MA)
Assignee: VLT, Inc. (Sunnyvale, CA)
Appl. No.: 11/143,102
Filed: June 1, 2005
POWER AND INFORMATION SIGNAL TRANSFER USING MICRO-TRANSFORMERS
Issued June 16, 2009
United States Patent 7,548,440
Chen, et al
A power converter provides power across an isolation barrier, such as through the use of coils. A coil driver has transistors connected in a positive feedback configuration and is coupled to a supply voltage in a controlled manner by measuring the output power and opening or closing a switch as needed between the power supply and the coil driver. An output circuit, such as a FET driver, can be used with or without isolation to provide power and a logic signal.
Inventors: Chen; Baoxing (Westford, MA), Kliger; Ronn (Lexington, MA)
Assignee: Analog Devices, Inc. (Norwood, MA)
Appl. No.: 11/594,328
Filed: November 6, 2006
ZERO-VOLTAGE-SWITCHING DC-DC CONVERTERS WITH SYNCHRONOUS RECTIFIERS
Issued June 16, 2009
United States Patent 7,548,435
Mao
A dc-dc converter includes an inductor, a synchronous rectifier (SR) connected to the inductor, and an active switch connected to the inductor and the SR. An active resonant tank (ART) cell is connected to the SR or a transformer in parallel such that a resonant capacitor of the ART cell is charged through the active switch and discharged through the synchronous rectifier so that during a switch transition period energy is pumped out of the resonant capacitor by activating the ART cell to eliminate reverse recovery switching loss and achieve zero voltage switching.
Inventors: Mao; Hong (Orlando, FL)
Assignee: Astec International Limited (Kwun Tong, Kowloon, HK)
Appl. No.: 11/485,007
Filed: July 12, 2006
GENERALIZED CANCELLATION OF INDUCTOR WINDING CAPACITANCE
Issued June 16, 2009
United States Patent 7,548,137
Wang, et al
An inductor device or filter such as an EMI filter, which includes an inductor, provides cancellation of parasitic capacitance of the inductor and extends high-frequency performance of the inductor or filter by using an inductor network (a special case being split windings) and including capacitors to couple signals corresponding to those which are passed by the equivalent parallel capacitance of an inductor of a network of inductorsósuch as in a multi-phase power supply of voltage converter to another inductor terminal, ground or an inductor in the ground return path. Cancellation of parasitic capacitance is provided for differential-mode and common-mode windings where the windings may be either inductively coupled or not. Forming the windings as a bifilar winding to increase coupling coefficient further improves performance and allows cancellation (as distinct from parasitic capacitance reduction) and avoidance of resonance in circuits in which an inductor is not permitted in the ground return path. Different inductance values and turns ratios of any or all inductors of the network, including multi-phase networks, may be accommodated.
Inventors: Wang; Shuo (Blacksburg, VA), Lee; Fred C. (Blacksburg, VA)
Assignee: Virginia Tech Intellectual Properties, Inc. (Blacksburg, VA)
Appl. No.: 11/850,762
Filed: September 6, 2007
SWITCHING-MODE POWER SUPPLY AND METHOD FOR DETERMINING A COMPENSATION FACTOR THEREOF
Issued June 16, 2009
United States Patent 7,548,048
Chang, et al
A switching-mode power supply is configured to have two modes: a normal mode and a measure mode. To determine a compensation factor to compensate the switching-mode power supply in the normal mode, the switching-mode power supply is switched to the measure mode to measure a frequency response of the switching-mode power supply, by which the switching mode power supply is accurately compensated and optimized.
Inventors: Chang; Wei-Hsu (Hsinchu, TW)
Assignee: Richtek Technology Corp. (Hsinchu, TW)
Appl. No.: 11/892,994
Filed: August 29, 2007
