Home | Links | Contact Us | More About Intellectual Property | Bookmark

Search patents:

Home

Electrical and Wave

Controller-for-DC-DC-converter

Circuit for electrostatic discharge (ESD) protection

OF THE INVENTION FIG. 1 depicts a partial block diagram, partial schematic diagram of an input/...

Tire deflation mechanism

OF THE DRAWINGS (FIGS. 1 AND 2) FIGS. 1 and 2 show a manually operated tire deflator mechanism ...

Battery pack and electronic apparatus using the same

Accordingly, an object of the present invention is to provide a high-safety battery pack at low ...

Battery charging system with power management of plural peripheral devices

OF THE PREFERRED EMBODIMENT While the specification concludes with claims defining the features of ...

Rechargeable battery charging circuit

Accordingly, it is therefore an object of the present invention to provide a novel battery charging ...

Power converter with increased breakdown voltage maintaining stable operation

In order to solve the above-mentioned problems in the conventional art, it is an object of the ...

Battery charger and charge control system

The present invention overcomes the foregoing and other shortcomings and drawbacks of battery ...

AC Line voltage regulator with controlled energy dispenser

The present invention is an apparatus for regulating an oscillating AC voltage, the apparatus ...

Electric motor control with integral battery charger

OF A PREFERRED EMBODIMENT An electric motor control with integral battery charger includes battery ...

Low cost electronic ultracapacitor interface technique to provide load leveling of a battery for pulsed load or motor traction drive applications

One object of the invention is to provide a simplified load leveling system for a battery in an ...

Controller for DC-DC converter

Details

Inventors: Takimoto, Kyuichi; Matsuyama, Toshiyuki; Ozawa, Hidekiyo; Kitagawa, Seiya;
Assignee: Fujitsu Limited (Kawasaki, JP)
Primary Examiner: Wong; Peter S.
Assistant Examiner: Tibbits; Pia
Attorney, Agent or Firm: Arent Fox Kintner Plotkin & Kahn, PLLC

A DC--DC converter generates a system output current and a battery charging current. The converter has an output transistor connected between an AC adapter, which provides a supply current, and a terminal at which the battery charging current is provided. A control circuit generates a duty control signal used to activate and deactivate the output transistor in order to adjust the battery charging current. The control circuit includes a voltage detection circuit that compares a DC power supply voltage of the AC adapter with a first reference voltage and generates a differential voltage signal from the comparison result. A PWM comparison circuit is connected to the voltage detection circuit and compares the differential voltage signal with a triangular wave signal to generate the duty control signal which has a duty ratio corresponding to the comparison result.

DETAILED DESCRIPTION Accordingly, it is an object of the present invention to provide a method and circuit for controlling a DC--DC converter that can fully utilize the capacity of the AC adapter without increasing cost.
To achieve the above object, the present invention provides a method for controlling a DC--DC converter that generates a system output current and a battery charging current from a supply current generated from a DC power supply voltage.
The method includes the steps of comparing the DC power supply voltage with a reference voltage and generating a differential voltage detection signal from the comparison result, comparing the differential voltage detection signal with a triangular wave signal and generating a duty control signal having a duty ratio corresponding to the comparison result, and controlling the supply current flowing through an output transistor to adjust the battery charging current by activating and deactivating the output transistor in accordance with the duty control signal.
In a further aspect of the present invention, a circuit for controlling a DC--DC converter that generates a system output current and a battery charging current from a supply current generated from a DC power supply voltage is provided.
The DC--DC converter includes an output transistor through which the supply current flows.
The control circuit includes a voltage detection circuit for comparing the DC power supply voltage with a first reference voltage and generating a differential voltage detection signal from the comparison result.
A PWM comparison circuit is connected to the voltage detection circuit to compare the differential voltage signal with a triangular wave signal and generate a duty control signal having a duty ratio corresponding to the comparison result.
The PWM comparison circuit provides the duty control signal to the output transistor to activate and deactivate the output transistor, thereby controlling the supply current flowing through the output transistor, and adjusting the battery charging current

Related patents

	Voltage cutoff compensation method for a battery in a charger OF THE PREFERRED EMBODIMENTS The Rc contact of FIG. 1 provides a voltage indicating the number of battery cells, the battery chemistry and the charge rate of a battery ...
	Apparatus and method of monitoring battery temperature during charging OF THE INVENTION Referring now to the drawing in detail, wherein identical numerals indicate the same elements throughout the figures, FIG. 1 depicts a handheld mobile ...
	Serial communication interface system having programmable microcontroller for use in a battery pack OF THE PREFERRED EMBODIMENT System Overview Referring to FIG. 1, a detailed block diagram illustrating microcontroller integrated circuit 10 embodying the present ...
	Battery monitoring circuit with storage of charge and discharge accumulation values accessible therefrom The present invention disclosed and claimed herein comprises a battery monitoring circuit for monitoring select parameters of a battery having positive and negative ...
	Circuit for determining the remaining operating life of a system The present invention overcomes the above identified problems as well as other shortcomings and deficiencies of existing technologies by providing oscillator driven gas ...
	Method for monitoring operating parameters of a rechargeable power supply The present invention overcomes the above identified problems as well as other shortcomings and deficiencies of existing technologies by providing a method for ...
	Anti-islanding method and apparatus for distributed power generation I claim: 1. A system for controlling power supplied to a utility network, comprising: a detector to detect a characteristic of power on a grid line of the utility ...
	Interface device receivable in card storage device slot of host computer The present invention has been made to solve the above-described problems, and a first object of the present invention is to provide an interface device which enables an ...
	Method and system for controlling and monitoring an array of point-of-load regulators The present invention provides a system and method for controlling and monitoring POL regulators within a distributed power system. In an embodiment of the invention, ...
	Electronic circuit arrangement having polarity reversal protection In addition to reliable polarity reversal protection, the solution according to the invention affords, in particular, the advantage of a small voltage drop across the ...

0.014
Archive: All patents - Links Copyright (c)2006 Eipa-patents.org - All rights reserved