Patents Represented by Attorney Henry N. Garrana
  • Patent number: 5596481
    Abstract: The present invention provides a portable computer having a palm rest integrated therein that allows the user to maintain a wrist-neutral position when using the portable computer. The portable computer comprises a computer chassis having a side wall adjoining a bottom that forms a footprint of the chassis, a keyboard positioned toward a rear end of the chassis, and a cover member covering a portion of an interior of the chassis. The portable computer further includes a palm rest integrated into the structure of the portable computer's chassis. The palm rest is comprised of a palm support that has front and rear ends and that is pivotable with respect to the chassis between a covering position and an elevated first palm support position. The palm support is pivotable about a hinge, that couples the palm support to the chassis. The palm rest further includes an adjustable extension structure having a first end coupled to the palm support and a second end coupled to a wall of the chassis.
    Type: Grant
    Filed: August 7, 1995
    Date of Patent: January 21, 1997
    Assignee: Dell USA, L.P.
    Inventors: Peter M. Liu, Robert L. McMahan
  • Patent number: 5594873
    Abstract: A method and apparatus for identifying option modules or expansion devices coupled to an expansion bus using time domain methods. According to the present invention, each expansion device includes logic circuitry that asserts an identification signal a preset time duration after a host reset signal is pulsed. A unique preset time duration or time constant is designated for each expansion device, and the host computer identifies each expansion device by the length or duration of the identification signal. In the preferred embodiment, during the power-on sequence the computer system asserts a reset signal pulse to the identification logic in each respective expansion device which directs the expansion device to assert its identifying signal. The host computer determines the length of time between assertion of the reset signal pulse and assertion of the identification signal and uses this information to determine the type of expansion device.
    Type: Grant
    Filed: December 8, 1994
    Date of Patent: January 14, 1997
    Assignee: Dell USA, L.P.
    Inventor: James E. Garrett
  • Patent number: 5592071
    Abstract: A synchronous regulator circuit including a transformer having a secondary inductor magnetically coupled to a primary inductor, where the secondary inductor is coupled to control a synchronous power switch. The secondary inductor operates to drive the synchronous power switch using self-regeneration during a flux reversal phase of each cycle. A timing circuit or simple pulse width modulation circuit (PWM) turns on the primary switch and turns off the synchronous switch during a power phase of each cycle, and then turns off the primary switch during the flux reversal phase of each cycle. The flux reversal of the secondary inductor drives the synchronous switch on, thereby achieving synchronous operation without an expensive dual output PWM. The present invention is illustrated using both a buck and a boost topology. A third switch is preferably used to clamp the synchronous switch off during the power phase.
    Type: Grant
    Filed: January 11, 1995
    Date of Patent: January 7, 1997
    Assignee: Dell USA, L.P.
    Inventor: Alan E. Brown
  • Patent number: 5592684
    Abstract: A store queue is provided that forms an interface between a primary bus and a secondary bus and which temporarily stores data to be written via a memory or I/O channel to a peripheral device. The store queue allows partial writes executed on the primary bus to be combined within a common word storage cell of an internal FIFO buffer regardless of whether the consecutive partial writes result in an invalid byte combination. If the data being transferred does not constitute an invalid byte combination, the store queue executes a single write cycle on the secondary bus. If the data contained by the word memory cell constitutes an invalid byte combination, the store queue executes two or more partial writes on the secondary bus to transfer the data in the order it was received. The store queue includes a byte order tracking circuit, such as an accumulation counter, for tracking the order in which the bytes are written from the primary bus.
    Type: Grant
    Filed: July 22, 1994
    Date of Patent: January 7, 1997
    Assignee: Dell USA, L.P.
    Inventors: Darius D. Gaskins, Terry J. Parks
  • Patent number: 5590338
    Abstract: A combined multiprocessor interrupt controller and interprocessor communication mechanism includes a system bus, an input/output bridge element coupled to the system bus, and a system controller coupled to the system bus. The input/output bridge element includes circuitry for receiving interrupt requests, for obtaining processor-associated vectors, and for packaging obtained processor-associated vectors into interprocessor communication messages. The system controller includes circuitry for receiving and decoding interprocessor communication messages, and for providing processor-associated vectors to the associated processor.
    Type: Grant
    Filed: August 8, 1995
    Date of Patent: December 31, 1996
    Assignee: Dell USA, L.P.
    Inventors: Terry J. Parks, Darius D. Gaskins
  • Patent number: 5590287
    Abstract: A digital computer system includes an interface for routing data which permits the transfer of data between mismatched devices. The computer system comprises a processor, memory and an interconnecting data bus, all configured to handle data units of a first data width. Also connected to the data bus is at least one I/O device configured to handle data units of a second data width. By adjusting the width of the data being transferred to match the width of the receiving device or bus, data may be transferred between devices of differing width. To adjust the width, control means are provided which modify the route along which data bytes are transferred based upon the width of the transferring and receiving devices and the direction of transfer are provided.
    Type: Grant
    Filed: March 7, 1994
    Date of Patent: December 31, 1996
    Assignee: Dell USA, L.P.
    Inventors: Charles P. Zeller, Terry J. Parks, Michael D. Durkin
  • Patent number: 5590363
    Abstract: A digital computer system includes a central processor unit (CPU) and an optional co-processor unit, both connected to a local bus. The co-processor unit, when installed, fits into a socket having pins, the pins being connected to communicate with the CPU through the local bus. A presence-detect circuit is connected to the local bus and receives a signal indicating the presence of the co-processor unit in the socket. Logic circuitry receives the output signal from the presence-detect circuit and provides a READY-- signal in either the presence or absence of the co-processor unit.
    Type: Grant
    Filed: May 14, 1993
    Date of Patent: December 31, 1996
    Assignee: Dell USA, L.P.
    Inventors: David R. Lunsford, Michael D. Durkin
  • Patent number: 5587885
    Abstract: To facilitate the registered connection between a laminated multi chip module and an associated multi-tiered circuit board, spaced series of vias are formed transversely through the circuit board and module substrates between their opposite first and second sides. Gold plated BGA leads, offset from the module substrate vias, are formed on the first module substrate side on multi-layer plating structures disposed thereon and extending along the module via interior side surfaces. A spaced series of relatively shallow, circularly cross-sectioned socket areas, offset from the circuit board vias, are also formed on the first side of the circuit board. The sockets have diameters slightly larger that those of the generally ball-shaped BGA leads of the multi chip module, and are positioned on the same centerline pattern as the leads.
    Type: Grant
    Filed: July 15, 1994
    Date of Patent: December 24, 1996
    Assignee: Dell USA, L.P.
    Inventor: N. Deepak Swamy
  • Patent number: 5581693
    Abstract: An apparatus and method for a computer system that selectively disables expansion peripheral interface devices so that they do not interfere with diagnostic testing of related computer system peripheral interface devices. The present invention selectively disables the peripheral interface devices by control of the clock signals thereto. The clock signals may be selectively controlled by means of a software test program that may also be used to automate the diagnostic testing of the computer system. In addition, the computer system may be remotely tested and diagnosed because the present invention makes it unnecessary for the physical removal of devices that may cause false signal responses during the diagnostic tests.
    Type: Grant
    Filed: December 1, 1995
    Date of Patent: December 3, 1996
    Assignee: Dell USA, L.P.
    Inventor: Victor Pecone
  • Patent number: 5581740
    Abstract: A CD ROM server comprises a CD ROM drive and an array of hard disk drives. Means are provided for copying data from the CD ROM drive to the array of hard disk drives, and for deleting data from the array of hard disk drives, upon receipt of copy and delete requests, respectively, from a host computer system. Means are provided for the host computer to read data from the array of hard disk drives in the CD ROM format that the data had been stored in on the CD ROM. Means are also available to implement RAID technology with the array of hard disk drives for data reconstruction, striping, and redundancy. Means may be provided for the host computer to communicate directly with any SCSI devices connected to the server.
    Type: Grant
    Filed: October 4, 1994
    Date of Patent: December 3, 1996
    Assignee: Dell USA, L.P.
    Inventor: Craig S. Jones
  • Patent number: 5579528
    Abstract: A macro-system which includes at least one portable computer and at least one stationary computer. The stationary computer includes a docking bay into which the portable computer is physically inserted whenever the user has returned with it to his primary work area. This docking station includes contact probes which automatically make contact to a small number of contacts on the back of the portable computer whenever it is stuffed into the docking station. The portable computer preferably includes soft power switch logic, so that an activation signal, received when the portable computer is docked, can be used to wake up the portable computer and bring it up active in a slave operating mode. Appropriate software routines can then be triggered to maintain file coherency.
    Type: Grant
    Filed: April 3, 1995
    Date of Patent: November 26, 1996
    Assignee: Dell USA, L.P.
    Inventor: David S. Register
  • Patent number: 5576609
    Abstract: A battery charger including a control system for controlling a linear pass element to maintain relatively constant power dissipation of the linear pass element. In one embodiment, the charge current and the voltage across the linear pass element are provided to a constant dissipation amplifier, which increases the charge current as the voltage of the linear pass element decreases due to charging of the battery. The charge current is increased in such a manner to maintain the power dissipation of the linear pass element to a relatively constant level. In another embodiment, the battery voltage is provided to the amplifier, which increases charge current in response to rising battery voltage to maintain constant power dissipation of the linear pass element. The latter embodiment is in recognition that the voltage across the linear pass element is inversely proportional to the voltage across the linear pass element.
    Type: Grant
    Filed: April 20, 1995
    Date of Patent: November 19, 1996
    Assignee: Dell USA, L.P.
    Inventors: Alan E. Brown, Farzad Khosrowpour
  • Patent number: 5572660
    Abstract: A fault tolerant disk array subsystem is provided that includes a plurality of data drives for storing real data and a parity drive for storing redundant data. Each data drive is associated with a dedicated write-through cache unit and the parity drive is associated with a dedicated write-back cache unit. An array scheduler schedules read and write operations to access the data drives and includes a parity control unit for updating parity information when new data is written to one of the data drives. Since a write-back caching technique is used to store updated parity information, the write latency of the parity drive does not limit the write-throughput of the disk array subsystem. Furthermore, since a non-volatile memory unit is provided to store the addresses of any dirty parity information within the write-back cache unit, parity information can be reconstructed in the event of a power failure.
    Type: Grant
    Filed: November 13, 1995
    Date of Patent: November 5, 1996
    Assignee: Dell USA, L.P.
    Inventor: Craig S. Jones
  • Patent number: 5571608
    Abstract: An embedded core laminate including a conductive reference plane interposed between two insulation layers, and further interposed between two conductive layers. The assembly is laminated using standard temperature and pressure laminating procedures. Holes for interconnect vias are preferably drilled into the reference plane before laminating. The resulting embedded core laminate has three conductive layers with relatively uniform separation, insuring improved impedance control on each PCB (printed circuit board). Since uniform separation is maintained from one PCB to another, multiple PCBs connected together using embedded core laminates according to the present invention allows minimum cross-talk and characteristic impedance variations from one PCB to the next.
    Type: Grant
    Filed: September 5, 1995
    Date of Patent: November 5, 1996
    Assignee: Dell USA, L.P.
    Inventor: N. Deepak Swamy
  • Patent number: 5572403
    Abstract: A cooling subsystem and method for a chassis of a computer system. The cooling subsystem comprises: (1) first and second cooling fans having first and second motors associated therewith for driving the first and second cooling fans, respectively and (2) a common plenum substantially shrouding and providing a pathway for air communication between the first and second cooling fans, the first and second fans cooperating to provide an optimum rate of air flow from without the chassis to within the chassis to provide air exchange within the chassis, the air flow within the chassis being in a predetermined direction to provide directed cooling of a specified device within the chassis, the common plenum allowing the first and second fans to continue to cooperate to provide a minimum air flow to provide a minimum air exchange within the chassis, the air flow remaining in the predetermined direction to continue the directed cooling of the specified device when a selected one of the first and second motors fails.
    Type: Grant
    Filed: January 18, 1995
    Date of Patent: November 5, 1996
    Assignee: Dell USA, L.P.
    Inventor: R. Steven Mills
  • Patent number: 5571996
    Abstract: A circuit board is provided having a plurality of vias and uniformly spaced connector stubs arranged upon one or both outer surfaces of the control board. Sets of trace conductors are formed within the control board between the vias. The trace conductors are arranged in two planes within the control board, wherein trace conductors within one plane are laterally offset from trace conductors in the other plane. Laterally offset trace conductors allow close spacing of the trace conductor planes while maximizing the spacing between trace conductors and corresponding reference conductors also placed within the control board. Additionally, the trace conductors are serpentine-shaped when viewed from a perspective perpendicular to the planar surface of the control board.
    Type: Grant
    Filed: January 17, 1995
    Date of Patent: November 5, 1996
    Assignee: Dell USA, L.P.
    Inventors: N. Deepak Swamy, Victor K. Pecone, Darrell Slupek
  • Patent number: 5568360
    Abstract: A heat transfer system is provided for dissipating thermal energy within the personal computer. The transfer system is designed to move heat from a heat source, such as a central processing unit (CPU), to a heatsink arranged upon the portable computer keyboard. The heat transfer mechanism includes a heat slug thermally coupled to the CPU heat source and a heat pipe thermally coupled to a backside surface of a computer keyboard. The heat pipe is designed having minimal thermal gradient, and includes an evaporation/condensation cycle associated with its operation. The heat pipe is preferably orthogonally shaped having at least one flat surface arranged near the intersection of the orthogonal members. The flat section is in registry with a heat source. Movement of the flat section relative to the heat source effectuates abutment and thermal contact therebetween.
    Type: Grant
    Filed: March 29, 1995
    Date of Patent: October 22, 1996
    Assignee: Dell USA, L.P.
    Inventors: Mark B. Penniman, Carmen M. Schlesener, Jim J. Kizer
  • Patent number: 5568610
    Abstract: A detection system for detecting the insertion or removal of expansion cards having a standard edge connector using one or more capacitive plates coupled to corresponding variable frequency oscillators. The capacitive plates are preferably mounted on an internal layer of the expansion card and preferably aligned with corresponding pins of the edge connector for establishing capacitive loading with respect to the corresponding pins. The frequency of the oscillators change with changes in the capacitive loading of the corresponding plates. The detection circuitry includes a processor which continuously monitors the frequency of the oscillators to thereby detect movement of the expansion card, and preferably includes a control and isolation circuit which electrically isolates the power and data pins during insertion and/or removal as controlled by the processor. The detection circuitry may be mounted to either on the expansion card or the planar of the computer system.
    Type: Grant
    Filed: May 15, 1995
    Date of Patent: October 22, 1996
    Assignee: Dell USA, L.P.
    Inventor: Alan E. Brown
  • Patent number: 5568350
    Abstract: A fusible link provided in a power supply of a computer system for providing evidence of an over temperature condition to document a fan failure in the event of catastrophic failure of the power supply. The power supply typically includes a temperature detection circuit often including a thermistor providing a signal indicative of an over temperature condition in the power supply. A latch circuit coupled to the temperature detection circuit shuts the power supply down in an attempt to prevent such catastrophic failure. In a circuit according to the present invention, a fuse is coupled to the temperature detection circuit where the fuse open-circuits when an over temperature condition is detected. Such blown fuse documents the over temperature condition. An external pin provided through a Zener diode and coupled to the fusible link enables external determination of the state of the fuse without disassembling the power supply.
    Type: Grant
    Filed: January 11, 1995
    Date of Patent: October 22, 1996
    Assignee: Dell USA, L.P.
    Inventor: Alan E. Brown
  • Patent number: 5568359
    Abstract: A portable computer desktop docking system includes a base structure, a port replicator, a shroud and a monitor stand. The base structure is horizontally supportable on a desktop and has an upwardly and rearwardly sloping top side with the port replicator being mounted on a rear section thereof. To dock the computer, it is manually slid rearwardly along the top side of the base structure until a rear side connector on the computer is forcibly mated with a front side connector on the port replicator. The port replicator has a rear side connectable to desktop peripheral device electrical cables. The shroud structure snaps onto a rear side of the base structure, conceals port replicator end portions of the cables, and groups the cables so that they exit the shroud structure in a horizontally central rear side portion thereof. The monitor stand has a monitor support platform from which four support legs depend.
    Type: Grant
    Filed: May 24, 1995
    Date of Patent: October 22, 1996
    Assignee: Dell USA, L.P.
    Inventors: Christopher Cavello, Steven Gluskoter, Damon Broder