Patents by Inventor Bing F. Ma

Bing F. Ma 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: 5418502
    Abstract: An R-C relaxation oscillator having two comparators and a silicon controlled rectifier dissipates very low average power without resulting in frequency instabilities due to circuit propagation delays. A timing capacitor C.sub.T is charged through a timing resistor R.sub.T. The first comparator compares the voltage across the timing capacitor with an upper threshold voltage V.sub.TH. When the voltage across the timing capacitor crosses the upper threshold voltage, the comparator turns on the silicon controlled rectifier, which causes the capacitor to discharge the voltage that it has stored. The second comparator turns off the silicon controlled rectifier when the voltage across the timing capacitor falls below a lower threshold voltage V.sub.TL.
    Type: Grant
    Filed: March 3, 1994
    Date of Patent: May 23, 1995
    Assignee: Micro Linear Corporation
    Inventors: Bing F. Ma, W. Richard Davis
  • Patent number: 5281862
    Abstract: An output circuit includes a totem-pole output circuit for driving a power MOSFET. A pull-up circuit and a pull-down circuit drive the output node low or high as required. The circuit prevents the pull-up and pull-down circuits from simultaneously conducting current. The pull-up circuit has a pull-up threshold voltage and the pull-down circuit has a pull-down threshold voltage such that the pull-up circuit is turned off before the pull-down circuit is activated when the output node is switched from a high state to a low state and further wherein the pull-down circuit is turned off before the pull-up circuit is activated when the output node switches from a low state to a high state. The pull-up circuit is held off when the output node is switched from a high state to a low state by two diodes from the output node to an input of the pull-up circuit.
    Type: Grant
    Filed: October 13, 1992
    Date of Patent: January 25, 1994
    Assignee: Micro Linear Corporation
    Inventor: Bing F. Ma
  • Patent number: 5023481
    Abstract: An output circuit having the output taken between a pull-up output transistor and a pull-down output transistor connected in series for conducting current alternatively. Separate pull-up and pull-down driver circuits are controlled by a common input signal. The pull-down driver circuit is supplied by a pull-down current source, and a diode is connected from the point between the pull-down driver transistor and pull-down current source to the output node. The effect of a large node capacitance is reduced by the diode, which conducts current from the pull-down current source to any output load capacitance to raise the output voltage more rapidly when the pull-down driver circuit is cut off.
    Type: Grant
    Filed: December 27, 1989
    Date of Patent: June 11, 1991
    Assignee: North American Philips Corporation
    Inventors: John Tero, Shaoan Chin, Bing F. Ma