Patents by Inventor Roy Tanikawa

Roy Tanikawa has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Power supply which provides a variable charging current to a battery in a portable computer system
    Patent number: 5625275
    Abstract: A power supply for a rechargeable battery in a portable computer system is disclosed which adjusts the level of charging current depending upon the current drawn by the portable computer system. The power supply includes an AC adapter which supplies input current for operating the computer system and for charging the battery. Sensors are connected to the AC adapter, the battery, and an output of the power supply to detect the level of input current from the AC adapter, the level of charging current supplied to the battery, and the output voltage level of the power supply. A controller is connected to each of the sensors and monitors the input current level, the charging current level, and the output voltage level. The controller generates a control signal which indicates whether any one of the levels has exceeded a respective predetermined maximum value.
    Type: Grant
    Filed: May 24, 1995
    Date of Patent: April 29, 1997
    Assignee: AST Research, Inc.
    Inventors: Roy Tanikawa, Hien Le