Patents by Inventor Donald Cho Lam Yu

Donald Cho Lam Yu 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).

  • Patent number: 7148658
    Abstract: A method for charge control of a photoflash capacitor. The method includes detecting a voltage on the photoflash capacitor, asserting and then latching a recharge signal when the detected voltage is lower than a first reference voltage, de-asserting and then latching the recharge signal when the detected voltage exceeds a second reference voltage, charging the photoflash capacitor when the recharge signal is asserted, and providing a pin for connection of a resistive element which determines the first reference voltage.
    Type: Grant
    Filed: February 5, 2004
    Date of Patent: December 12, 2006
    Assignee: Yobon Technologies, Inc.
    Inventor: Donald Cho Lam Yu
  • Patent number: 6956358
    Abstract: A method for charge control of a photoflash capacitor. The method includes generating an input current to induce a charge current for the photoflash capacitor when an activation signal is asserted, detecting a first voltage from the photoflash capacitor and a second voltage corresponding to the input current, asserting and de-asserting a recharge signal respectively when the first detected voltage is lower and higher than a first reference voltage, asserting and de-asserting a current limit signal respectively when the second detected voltage is higher and lower than a second reference voltage, asserting the activation signal only when the recharge signal is asserted and the current limit signal is de-asserted, and providing a pin for connection of a resistive element which determines the second reference voltage.
    Type: Grant
    Filed: February 5, 2004
    Date of Patent: October 18, 2005
    Assignee: Yobon Technologies, Inc.
    Inventor: Donald Cho Lam Yu