Patents by Inventor Abdul M. Elhatem

Abdul M. Elhatem 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: 6825513
    Abstract: A high power MOSFET semiconductor having a high breakdown voltage. The new power device concept that reaches an area of a lower specific on-resistance, higher breakdown voltage and reduced device silicon area. This device architecture is built on the concepts of charge compensation in the drift region of the device. Where, the doping of the vertical drift region is increased by one order of magnitude. To counterbalance the added charges, fine-structured wells of opposite doping type to the drift region are introduced as part of the device structure. The charge compensation wells do not contribute to the on-state current conduction, therefore, this novel new generation of high voltage device architecture breaks the limit line of silicon. This architecture may extend to higher material resistivity and larger geometry to increase the voltage to 1kv plus.
    Type: Grant
    Filed: September 27, 2002
    Date of Patent: November 30, 2004
    Assignee: Xerox Corporation
    Inventor: Abdul M. ElHatem
  • Publication number: 20040061182
    Abstract: A high power MOSFET semiconductor having a high breakdown voltage. The new power device concept that reaches an area of a lower specific on-resistance, higher breakdown voltage and reduced device silicon area. This device architecture is built on the concepts of charge compensation in the drift region of the device. Where, the doping of the vertical drift region is increased by one order of magnitude. To counterbalance the added charges, fine-structured wells of opposite doping type to the drift region are introduced as part of the device structure. The charge compensation wells do not contribute to the on-state current conduction, therefore, this novel new generation of high voltage device architecture breaks the limit line of silicon. This architecture may extend to higher material resistivity and larger geometry to increase the voltage to 1 kv plus.
    Type: Application
    Filed: September 27, 2002
    Publication date: April 1, 2004
    Applicant: Xerox Corporation
    Inventor: Abdul M. ElHatem
  • Patent number: 6416163
    Abstract: Described are various compensation circuit designs to ensure proper shutoff of an unselected transducer in a transducer switching matrix. The switch of an unselected transducer is moved to a strong OFF state by injection of a compensation current. The compensation network is implemented as semiconductor integrated circuits which provide a high-voltage column switching diode, and a compensation switch. The compensation switch and column switching diode are configured such that they are isolated from each other.
    Type: Grant
    Filed: November 22, 1999
    Date of Patent: July 9, 2002
    Assignee: Xerox Corporation
    Inventors: Abdul M. ElHatem, Lamar T. Baker, Jaime Lerma, Mostafa R. Yazdy
  • Patent number: 6299272
    Abstract: An acoustic inkjet printhead utilizes a pulse width modulation to control droplet size or ejection velocity. An individual control pulse controls the duration and the time a RF signal is applied to each transducer. To modify the RF signal of each transducer, the pulse width of each control signal can be modified according to a predetermined correction data. The rising edge of the control data is delayed according to the correction data while the falling edge is kept the same.
    Type: Grant
    Filed: October 28, 1999
    Date of Patent: October 9, 2001
    Assignee: Xerox Corporation
    Inventors: Lamar T. Baker, Steven A. Buhler, Abdul M. Elhatem, Scott A. Elrod, Babur B. Hadimioglu, Jaime Lerma, Mostafa R. Yazdy
  • Patent number: 6290342
    Abstract: A device for the transport of particulate marking material includes a plurality of interdigitated electrodes formed on a substrate. An electrostatic traveling wave may be generated across the electrodes to sequentially attract particles of marking material, and thereby transport them to a desired location. The electrodes may be integrally formed with driving circuitry, and may be staggered to minimize or eliminate cross-talk.
    Type: Grant
    Filed: September 30, 1998
    Date of Patent: September 18, 2001
    Assignee: Xerox Corporation
    Inventors: Tuan Anh Vo, Dan A. Hays, Eric Peeters, Abdul M. Elhatem, Kaiser H. Wong, Joel A. Kubby, Jaan Noolandi
  • Patent number: 5920750
    Abstract: A compact design for the electronic circuits to provide electrical contact to a SED roll of a segmented electrode development unit is provided. In this invention, the required high voltage and low voltage circuitry is placed on a printed flexible circuit which is folded and rolled into a cylindrical circuit to be connected to the SED roll. The flexible printed circuit has a plurality of output terminals each of which will be connected to one of the electrodes of the SED roll and a plurality of input terminals each of which will be connected to a terminal of a slip ring to receive the required electrical power.
    Type: Grant
    Filed: March 28, 1997
    Date of Patent: July 6, 1999
    Assignee: Xerox Corporation
    Inventors: William H. Wayman, Abdul M. Elhatem
  • Patent number: 5892303
    Abstract: A compact design for the electronic circuits to provide electrical contact to a SED roll of a segmented electrode development unit is provided. In this invention, all the required high voltage and low voltage circuitry is placed on a printed flexible circuit which is folded and rolled into a cylindrical circuit to be connected to the SED roll. The flexible printed circuit has a plurality of output terminals each of which will be connected to one of the electrodes of the SED roll.
    Type: Grant
    Filed: March 28, 1997
    Date of Patent: April 6, 1999
    Assignee: Xerox Corporation
    Inventors: William H. Wayman, Abdul M. Elhatem, Paul C. Tien, Tuan Anh Vo
  • Patent number: 5822652
    Abstract: There is disclosed a compact design for the electronic circuits required to provide electrical contact to a SED roll of a segmented electrode development unit. In this invention, all the required high voltage and low voltage circuitry is placed on a printed flexible circuit which is folded and rolled into a cylindrical circuit to be connected to the SED roll. The flexible printed circuit has a plurality of output terminals each of which will be connected to one of the electrodes of the SED roll. In this invention, a spool is used to support the connection of the cylindrical circuit to the SED roll.
    Type: Grant
    Filed: March 28, 1997
    Date of Patent: October 13, 1998
    Assignee: Xerox Corporation
    Inventors: Abdul M. Elhatem, William H. Wayman, Paul C. Tien, Tuan Anh Vo
  • Patent number: 5754193
    Abstract: An inkjet printhead addressing and firing design which minimizes voltage drop differential occurring on a power bus which supplies power to fire individual ink jets due to current loads needed to fire the individual ink jets. The voltage drop differential can be reduced in part by firing a group of individual jets which are spaced out over the entire length of the array instead of firing a group of adjacent jets. Spacing of the firing jets will insure that less than an entire amount of current needed to fire a group of jets will be needed in the center of the bus. Reducing the amount of current needed to travel the length of the bus reduces the voltage drop differential on the bus caused by current conduction along the bus.
    Type: Grant
    Filed: January 9, 1995
    Date of Patent: May 19, 1998
    Assignee: Xerox Corporation
    Inventor: Abdul M. Elhatem
  • Patent number: 5739582
    Abstract: A method in which several high voltage chips may be packaged within a single, typically low voltage plastic package. The high voltage chips are packaged to remain electrically isolated from each other to avoid undesirable side effects such as arcing between the chips but able to share electronic data and communicate with each other electronically through their input and ouput nodes. Due to the unique packaging method, the typically low voltage plastic packaging can be made to withstand operating voltages up to 35 times greater than previously attained by such low voltage plastic packaging.
    Type: Grant
    Filed: November 24, 1995
    Date of Patent: April 14, 1998
    Assignee: Xerox Corporation
    Inventors: Abdul M. ElHatem, Hung C. Nguyen, Mohammad Mojarradi
  • Patent number: 5699231
    Abstract: An electronic circuit package in which several high voltage components are packaged along with low voltage components using standard circuit boards and minimizing the space needed for the entire assembly. A miniature circuit board, constructed of standard circuit board material, is used to mount several electronic components, some of which require high voltages. To meet isolation requirements, requiring a dielectric strength more than that provided by the board itself, between the high and low voltage nodes the circuit board incorporates slots or other cut out shapes in the board. The slots or other cut out shapes provide two functions. The first use for the slots or other cut out shapes is to prevent charge migration on the surface of the board between high and low voltage nodes. This is accomplished by placing the slots or other cut out shapes between high and low voltage nodes. The circuit board is then encapsulated within a potting material.
    Type: Grant
    Filed: November 24, 1995
    Date of Patent: December 16, 1997
    Assignee: Xerox Corporation
    Inventors: Abdul M. ElHatem, Mohammad M. Mojarradi
  • Patent number: 5600149
    Abstract: An improved optically controlled power supply regulator in which an optoisolator transistor is controlled by an input light emitting diode replaces an optically controlled power supply regulator with a light emitting diode controlled with a light dependent resistor. The optically controlled power supply regulator utilizes a capacitor and a resistor to reduce loop response oscillation in order to prevent the optically controlled power supply regulator from being shut down on a system board.
    Type: Grant
    Filed: October 30, 1995
    Date of Patent: February 4, 1997
    Assignee: Xerox Corporation
    Inventors: Abdul M. ElHatem, Mohammad M. Mojarradi, Masaji Sato
  • Patent number: 5258638
    Abstract: A layout of a MOSFET current driver is disclosed which improves the fabrication yield and the current drive capability over that of the prior art while keeping the layout area the same as the prior art. In this design, the gate is laid out to have a lateral serpentine pattern rather than a vertical serpentine pattern to create a larger gate in order to improve the current drive capability. In addition, the contacts for the drain and the contacts for the source are removed from the gate layout area which facilitates condensing the gate layout and increasing the size of the gate. Also, this design has only two metal strips: one for the drain and one for the source of the MOSFET current driver. The two metal strips substantially overlap the serpentine patterned gate. Having only two metal strips reduces the spaces between the metal strips to one space thereby reducing the probability of having a short or a defect and improving the fabrication yield.
    Type: Grant
    Filed: August 13, 1992
    Date of Patent: November 2, 1993
    Assignee: Xerox Corporation
    Inventors: Abdul M. Elhatem, Steven A. Buhler
  • Patent number: 4899180
    Abstract: This bubblejet device has integrated into it a number of heater resistors and a temperature sensor which operate in conjunction with a temperature regulating circuit to heat the chip to its optimum operating temperature within seconds of turn-on, and thereafter maintain that temperature regardless of local temperature variations. The precise temperature regulation of the array improves print quality.
    Type: Grant
    Filed: April 29, 1988
    Date of Patent: February 6, 1990
    Assignee: Xerox Corporation
    Inventors: Abdul M. Elhatem, Steven A. Buhler
  • Patent number: 4853718
    Abstract: The ink in an ink jet is sensed by a capacitor, one plate of which is coupled to ground through the ink. The absence of ink will appear as a decreased amount of capacitance. In this case the charge of the capacitor will leak off faster, and a sample and hold circuit can sense this to output a signal indicating the absence of ink. The charging signal can either be generated on the chip, which is made from silicon, or can be supplied to the chip. The number of pins on the chip taken for this sensing function can be minimized by multplexing the states of signals supplied to the chip for other purposes to generate the necessary signals to control and operate this sensor.
    Type: Grant
    Filed: August 15, 1988
    Date of Patent: August 1, 1989
    Assignee: Xerox Corporation
    Inventors: Abdul M. ElHatem, Steven A. Buhler