Patents by Inventor Keming W. Yeh

Keming W. Yeh 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: 6516035
    Abstract: A method includes a data encoding scheme that has a run length limit of (1,6) and a 25% duty cycle. With error correction, the method achieves an effective run length limit of (2,9). The method can be used in conjunction with a packetized communication protocol to allow multiple controllers to communicate with multiple peripheral devices in a wireless data network. Peripheral devices include pointing devices, keyboards and game pads.
    Type: Grant
    Filed: April 7, 2000
    Date of Patent: February 4, 2003
    Assignee: ActiSys Corporation
    Inventors: Lichen Wang, Keming W. Yeh
  • Patent number: 5666495
    Abstract: A portable information storage and transfer device for use with IC memory card-based portable computers obviates many operations traditionally requiring a desktop computer. The floppy disk drive in the information storage and transfer device allows large amount of data and software programs to be made available to the IC memory card-based computer on floppy disks. The contents of such floppy disk can then be transferred for use in the portable computer on a blank IC memory card or the portable computer's system memory. Information entered into and stored in the system memory or an IC memory card of the portable computer can also be transferred through the information storage and transfer device to floppy disks, to a printer, to various peripheral devices or to a host computer. A built-in modem for accessing facsimile machines, other modems and the telephone system is also provided.
    Type: Grant
    Filed: February 16, 1996
    Date of Patent: September 9, 1997
    Inventor: Keming W. Yeh
  • Patent number: 5574859
    Abstract: A portable information storage and transfer device for use with IC memory card-based portable computers performs many data transfer operations. The floppy disk drive in the information storage and transfer device allows large amount of data and software programs to be made available to the IC memory card-based computer on floppy disks. The contents of such floppy disk can then be transferred for use in the portable computer on a blank IC memory card or the portable computer's system memory. Information entered into and stored in the system memory or an IC memory card of the portable computer can also be transferred through the information storage and transfer device to floppy disks, to a printer, to various peripheral devices or to a host computer. A built-in modem for accessing facsimile machines, other modems and the telephone system is also provided.
    Type: Grant
    Filed: January 26, 1993
    Date of Patent: November 12, 1996
    Inventor: Keming W. Yeh
  • Patent number: 5528758
    Abstract: A portable information storage and transfer device for use with IC memory card-based portable computers obviates many operations traditionally requiring a desktop computer. The floppy disk drive in the information storage and transfer device allows large amount of data and software programs to be made available to the IC memory card-based computer on floppy disks. The contents of such floppy disk can then be transferred for use in the portable computer on a blank IC memory card or the portable computer's system memory. Information entered into and stored in the system memory or an IC memory card of the portable computer can also be transferred through the information storage and transfer device to floppy disks, to a printer, to various peripheral devices or to a host computer. A built-in modem for accessing facsimile machines, other modems and the telephone system is also provided.
    Type: Grant
    Filed: November 13, 1992
    Date of Patent: June 18, 1996
    Inventor: Keming W. Yeh
  • Patent number: 5497464
    Abstract: A portable information storage and transfer device for use with integrated circuit (IC) memory card-based palmtop computers obviates many operations traditionally requiring a desktop computer. An external floppy disk drive allows large amount of data and software programs to be made available to the IC memory card-based computer on floppy disks. In addition, two memory card slots are provided to allow reading and writing IC memory card under either the proprietary format of the palmtop computer or an industry standard format, such as Personal Computer Memory Card International Association (PCMIA). Data interchange is thus between media written under disparate operating systems, file structures and basic input/output structures.
    Type: Grant
    Filed: June 24, 1993
    Date of Patent: March 5, 1996
    Inventor: Keming W. Yeh
  • Patent number: 4407004
    Abstract: Disclosed herein is a structure and process for a self-aligned metal semiconductor field effect transistor having the characteristics of a high speed, high density, low power LSI circuit and specifically an improved high device gain MESFET device using conventional photographic techniques. The inventive MESFET device has improved high device gain as a result of the elimination of series resistance, increased circuit integration density, and improved speed capability due to the elimination of spacings between gate and drain and gate and source and the improved high device gain.
    Type: Grant
    Filed: February 12, 1981
    Date of Patent: September 27, 1983
    Assignee: Xerox Corporation
    Inventor: Keming W. Yeh
  • Patent number: 4400866
    Abstract: A semiconductor structure and particularly a high-speed VLSI self-aligned Schottky Metal Semi-Conductor Field Effect Transistor having a relatively high operating frequency and low series resistance, predicated upon very controllable small structure geometries made by the growth of oxide bumper insulators on either side of the schottky barrier. The oxide bumpers width is relatively thicker than the depth of the initial silicon dioxide layer on the substrate surface thereby providing effective separation of the gate from the source and drain respectively. Accordingly, spatial separations between the self-aligned gate-and-drain and gate-and-source can be relatively very closely controlled by varying the doping level of an intermediate polysilicon layer thereby providing controllable differential polysilicon oxidation rates for the bumpers. Thus, the series resistance can be controlled to be relatively low thereby providing a VLSI SASMESFET device that can be operated at relatively high speeds.
    Type: Grant
    Filed: April 5, 1982
    Date of Patent: August 30, 1983
    Assignee: Xerox Corporation
    Inventors: Keming W. Yeh, Izya Bol
  • Patent number: 4375643
    Abstract: A semiconductor structure and particularly a high-speed VLSI self-aligned Schottky Metal Semi-Conductor Field Effect Transistor having a relatively high operating frequency and low series resistance, predicated upon very controllable small structure geometries made by the growth of oxide bumper insulators on either side of the schottky barrier. The oxide bumpers width is relatively thicker than the depth of the initial silicon dioxide layer on the substrate surface thereby providing effective separation of the gate from the source and drain respectively. Accordingly, spatial separations between the self-aligned gate-and-drain and gate-and-source can be relatively very closely controlled by varying the doping level of an intermediate polysilicon layer thereby providing controllable differential polysilicon oxidation rates for the bumpers. Thus, the series resistance can be controlled to be relatively low thereby providing a VLSI SASMESFET device that can be operated at relatively high speeds.
    Type: Grant
    Filed: February 14, 1980
    Date of Patent: March 1, 1983
    Assignee: Xerox Corporation
    Inventors: Keming W. Yeh, Izya Bol
  • Patent number: 4333225
    Abstract: A circular high voltage field effect transistor suitable for inclusion in LSI circuits, and the process for making said transistor, are described. The transistor comprises a central drain and concentric circular field plate, gate and source. Alternate embodiments include an intermediate gate and resistive gate. Implantation and diffusion techniques are described for producing the source and channel regions, and various device dimensions may be varied to improve either current or voltage handling capability or speed capability.
    Type: Grant
    Filed: December 11, 1980
    Date of Patent: June 8, 1982
    Assignee: Xerox Corporation
    Inventor: Keming W. Yeh
  • Patent number: 4308549
    Abstract: A circular high voltage field effect transistor suitable for inclusion in LSI circuits, and the process for making said transistor, are described. The transistor comprises a central drain and concentric circular field plate, gate and source. Alternate embodiments include an intermediate gate and resistive gate. Implantation and diffusion techniques are described for producing the source and channel regions, and various device dimensions may be varied to improve either current or voltage handling capability or speed capability.
    Type: Grant
    Filed: December 18, 1978
    Date of Patent: December 29, 1981
    Assignee: Xerox Corporation
    Inventor: Keming W. Yeh
  • Patent number: 4304042
    Abstract: Disclosed herein is a structure and process for a self-aligned metal semiconductor field effect transistor having the characteristics of a high speed, high density, low power LSI circuit and specifically an improved high device gain MESFET device using conventional photographic techniques. The inventive MESFET device has improved high device gain as a result of the elimination of series resistance, increased circuit integration density, and improved speed capability due to the elimination of spacings between gate and drain and gate and source and the improved high device gain.
    Type: Grant
    Filed: July 23, 1980
    Date of Patent: December 8, 1981
    Assignee: Xerox Corporation
    Inventor: Keming W. Yeh
  • Patent number: 4206005
    Abstract: A split gate VMOSFET having an enhancement transistor and a depletion load transistor on opposing sidewalls of a V-groove region. In the process, a differential oxidation rate due to the different crystal orientations of the substrate is used to complete device fabrication in a relatively simple manner. The resultant process steps make it possible to fabricate a VMOSFET having symmetrical geometry in which a transfer gate can be easily implemented.
    Type: Grant
    Filed: November 27, 1978
    Date of Patent: June 3, 1980
    Assignee: Xerox Corporation
    Inventors: Keming W. Yeh, James L. Reuter
  • Patent number: 4193079
    Abstract: A high frequency FET having a channel region and wherein said channel region contains an implant, said implant having a first dosage concentration at a first distance from the gate of said FET and a second dosage concentration at a second distance from the said gate and wherein said first distance is larger than said second distance and said first dosage concentration is larger than said second dosage concentration.
    Type: Grant
    Filed: January 30, 1978
    Date of Patent: March 11, 1980
    Assignee: Xerox Corporation
    Inventor: Keming W. Yeh
  • Patent number: 4163988
    Abstract: A split gate V groove FET device mounted in a substrate with a first terminal comprising a body of a first conductive material in the apex of said V groove, said first terminal connected to a first conductive channel in a first side of said V groove to form a first transistor and said first terminal connected to a second conductive channel in a second side of said V groove to form a second transistor.
    Type: Grant
    Filed: January 30, 1978
    Date of Patent: August 7, 1979
    Assignee: Xerox Corporation
    Inventors: Keming W. Yeh, James L. Reuter