Patents Assigned to Dallas Semiconductor Corporation
  • Patent number: 5961356
    Abstract: A receptacle apparatus for a compact electronic module for effectuating data communication between the module and an interface circuit. The receptacle apparatus includes a cover arrangement and a combined locking and communication effecting structure. The receptacle apparatus is also designed in various embodiments to be installed on a removeable cover of a system so as not to hamper with removal of that cover.
    Type: Grant
    Filed: May 1, 1998
    Date of Patent: October 5, 1999
    Assignee: Dallas Semiconductor Corporation
    Inventor: Nicholas M. G. Fekete
  • Patent number: 5963105
    Abstract: In an integrated crystal-less device that generates an output signal with the frequency of the output signal dependent at least in part on a resistive element, there is provided circuitry for providing compensation for the temperature coefficient the of resistive element, the circuitry includes a bandgap reference and a resistive network. The bandgap reference utilizes components having stable temperature coefficient to generate a first voltage, a reference voltage, and also to generate second voltage, a voltage proportional to absolute temperature. The resistive network includes two trimmable resistors, which are trimmed such that the resistive network in combination with the bandgap reference compensates for the absolute value of the resistive element in a selected temperature range.
    Type: Grant
    Filed: July 31, 1997
    Date of Patent: October 5, 1999
    Assignee: Dallas Semiconductor Corporation
    Inventor: Cong Dinh Nguyen
  • Patent number: 5949880
    Abstract: The present invention relates to system, apparatus and method for communicating valuable data from a portable module to another module via an electronic device. More specifically, the disclosed system, apparatus and method are useful for enabling a user to fill a portable module with a cash equivalent and to spend the cash equivalent at a variety of locations. The disclosed system incorporates an encryption/decryption method.
    Type: Grant
    Filed: November 26, 1997
    Date of Patent: September 7, 1999
    Assignee: Dallas Semiconductor Corporation
    Inventors: Stephen M. Curry, Donald W. Loomis, Michael L. Bolan
  • Patent number: 5940510
    Abstract: The present invention rotates to system, apparatus and method for communicating valuable data from a portable module to another module via an electronic device. More specifically, the disclosed system, apparatus and method are useful for enabling a user to fill a portable module with a cash equivalent and to spend the cash equivalent at a variety of locations. The disclosed system incorporates an encryption/decryption method.
    Type: Grant
    Filed: January 31, 1996
    Date of Patent: August 17, 1999
    Assignee: Dallas Semiconductor Corporation
    Inventors: Stephen M. Curry, Donald W. Loomis, Michael L. Bolan
  • Patent number: 5933039
    Abstract: Digital signal delay lines with electrically programmable and trimmable delay times, including electrically erasable and reprogrammable delay times. Floating gate field effect transistors are programmed to select current, capacitance, and/or threshold and thereby set a delay time determined by acurrent charging of a capacitor up to a threshold voltage. Trimming after packaging avoids package offsets. Temperature and power supply voltage compensation by current combining gives compensation compatible with the electrical programming.
    Type: Grant
    Filed: March 25, 1997
    Date of Patent: August 3, 1999
    Assignee: Dallas Semiconductor Corporation
    Inventors: Titkwan Hui, Robert W. Mounger
  • Patent number: 5913552
    Abstract: A thermal protection system that assembly of at least one electrical components and a heat shield surrounding the electrical component, wherein the heat shield forms a pocket between the electrical element and the heat shield and associated methods. The electrical element has at least one electrical lead. The system permits the electrical lead(s) to increase in temperature sufficient to permit soldering of the electrical lead(s) to a second electrical element. The thermal protection system also comprises a heat sink to protect the electrical element, which comprises a heat capacity material. The system also comprises electrical lead(s) with a low-cross sectional area.
    Type: Grant
    Filed: August 19, 1997
    Date of Patent: June 22, 1999
    Assignee: Dallas Semiconductor Corporation
    Inventors: Neil McLellan, Mike Strittmatter
  • Patent number: 5914543
    Abstract: A memory controller for supplying backup battery power when a main power supply voltage drops together with programmable plus power fail write protection. The controller includes supravoltage induced sleep mode operation, MOS switching between backup batteries during backup operation based on battery voltage levels and discharge circuitry for battery disposal.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: June 22, 1999
    Assignee: Dallas Semiconductor Corporation
    Inventors: Francis A. Scherpenberg, Eric W. Mumper, John W. Rea, Robert D. Lee
  • Patent number: 5904590
    Abstract: A receptacle apparatus for a compact electronic module for effectuating data communication between the module and an interface circuit. The receptacle apparatus includes a cover arrangement and a combined locking and communication effecting structure. The receptacle apparatus is also designed in various embodiments to be installed on a removeable cover of a system so as not to hamper with removal of that cover.
    Type: Grant
    Filed: December 22, 1995
    Date of Patent: May 18, 1999
    Assignee: Dallas Semiconductor Corporation
    Inventor: Nicholas M. G. Fekete
  • Patent number: 5903767
    Abstract: A system which includes a microprocessor (or microcontroller) and an auxiliary chip which monitors the system power supply voltage and performs related functions for the microprocessor. Another of the innovative teachings set forth in the present application is that the microprocessor can access the auxiliary chip to ascertain the power history. That is, the microprocessor can direct an interrupt to the auxiliary chip, which will cause the auxiliary chip to respond with a signal which indicates to the microprocessor whether the power supply voltage is heading up or down. When the microprocessor is reset at power-up, and detects that the power supply voltage is still marginal, the present invention permits the microprocessor to determine (by querying the auxiliary chip) whether the supply voltage is marginal so that the microprocessor does not go into full operation until the supply voltage is high enough.
    Type: Grant
    Filed: April 7, 1997
    Date of Patent: May 11, 1999
    Assignee: Dallas Semiconductor Corporation
    Inventor: Wendell L. Little
  • Patent number: 5867006
    Abstract: A battery charger with charging parameter values derived from communication with a battery pack to be charged. Communication is over a one-wire bus with battery pack transmissions in response to charger inquiries. The battery charger may be in the form an integrated circuit driving a power transistor or other controllable DC supply. A battery pack may contain a program with multiple charging currents and charging interval termination methods such as time, temperature rise, and incremental voltage polarity. A lack of communication may be invoke a default charging program or denial of access to the charger. The charger also communicates over a high-speed three-wire bus with an external computer for analysis of identification information acquired from the battery and for control of the charger.
    Type: Grant
    Filed: July 28, 1997
    Date of Patent: February 2, 1999
    Assignee: Dallas Semiconductor Corporation
    Inventors: Donald R. Dias, Robert D. Lee
  • Patent number: 5864872
    Abstract: A communication circuit is provided in which reads from a device are controlled by sensing a transition by a host communicating with a device. The device then accepts a one which holds the line high for a predetermined time period or accepts a zero when the line is held high for a different time period. The sending of data is accomplished in a symmetrical relationship by having the device after the host pulls the line high by either by allowing the line to remain high or forcing the line to ground within the requisite time periods. This allows the "slave" device to consume almost no power in either the read or the write modes.
    Type: Grant
    Filed: May 28, 1996
    Date of Patent: January 26, 1999
    Assignee: Dallas Semiconductor Corporation
    Inventors: Robert D. Lee, Stephen M. Curry, Michael L. Bolan, Hal Kurkowski, Donald R. Diaz, Francis A. Scherpenberg, Kevin E. Deierling
  • Patent number: 5862354
    Abstract: A processor system is disclosed wherein said processor system is adapted to communicate over at least one one-wire network utilizing one-wire communications protocol. For the embodiment of the invention in which the processor system acts as a network master, the processor system includes a master UART especially configured to control communications over such network according to one-wire protocol. For the embodiment of the invention in which the processor communicates over two one-wire networks, the processor system includes a first UART which acts as a slave and a second UART which acts as a master.
    Type: Grant
    Filed: March 5, 1996
    Date of Patent: January 19, 1999
    Assignee: Dallas Semiconductor Corporation
    Inventors: Andreas Curiger, Wendell L. Little, Matthew K. Adams
  • Patent number: 5850450
    Abstract: A portable electronic data module for secure transactions, the electronic data module having a random number generator and an optimized co-processor for producing unbreakable key sets for a two-key cryptosystem. A real-time clock is sampled depending upon an external random event series such as power-ups of the data module by a host apparatus, and based upon the contents of the sample thus obtained, the entropy of a previously-loaded accumulator is further enhanced to achieve a pool of true random numbers. By repeatedly requesting random bytes of information from said pool of random numbers, large random numbers are created which are then rendered prime and used for key set creation.
    Type: Grant
    Filed: July 19, 1996
    Date of Patent: December 15, 1998
    Assignee: Dallas Semiconductor Corporation
    Inventors: Peter Schweitzer, Stephen M. Curry, Wendell L. Little, Bryan M. Armstrong, Christopher W. Fox, Donald W. Loomis
  • Patent number: 5848541
    Abstract: A retrofit door knob assembly is adapted to fit within an aperture in a door in place of a conventional mechanical lock assembly. The retrofit door knob assembly is similar in appearance to a conventional door handle assembly, but includes a motor coupled to a latch, and suitable electrical and mechanical key inserts for receiving separate electrical and mechanical keys. Either a mechanical or electrical key can operate the latch. The electrical key insert includes a data probe within the handle for receiving the electrical key and the electrical key is provided with a means for gripping to allow a user to turn the handle with the key after the latch is unlocked by the motor.
    Type: Grant
    Filed: November 29, 1994
    Date of Patent: December 15, 1998
    Assignee: Dallas Semiconductor Corporation
    Inventors: Mark Glick, Nicholas M. G. Fekete, Michael L. Bolan, Jeffrey D. Owens
  • Patent number: 5838256
    Abstract: An integrated circuit with three independently programmable "time bomb" functions. The integrated circuit can be set to disable itself after a certain number of power-up cycles, or after a certain total duration of operation, or after a certain absolute time and date. This is particularly advantageous for authorization functions, where the manufacturer may want to enable the user to "test drive" a demonstration or rental item of hardware or software.
    Type: Grant
    Filed: June 20, 1995
    Date of Patent: November 17, 1998
    Assignee: Dallas Semiconductor Corporation
    Inventors: Ronald W. Pearson, Michael L. Bolan
  • Patent number: 5834834
    Abstract: The present invention relates to mounting and adhesion systems and methods for compact electronic modules. More particularly, the present invention relates to an apparatus and technique for mounting an electronic module that is capable of communicating with an interface unit on a one-way-bus.
    Type: Grant
    Filed: December 1, 1994
    Date of Patent: November 10, 1998
    Assignee: Dallas Semiconductor Corporation
    Inventors: Robert D. Lee, Steven Hass, Michael L. Bolan, Hal Kurkowski
  • Patent number: 5832207
    Abstract: An electronic module having at least a microprocessor and co-processor on a single integrated circuit. The electronic module can be contained in a small housing. The electronic module provides secure bidirectional data communication via a data bus. The electronic module may include integrated circuit comprising a microprocessor, and a co-processor adapted to handle 1,024-bit modulo mathematics primarily aimed at RSA calculations. The electronic module is preferably contained in a small token sized metallic container and will preferably communicate via a single wire data bus which uses a one-wire protocol.
    Type: Grant
    Filed: July 19, 1996
    Date of Patent: November 3, 1998
    Assignee: Dallas Semiconductor Corporation
    Inventors: Wendell Little, Andreas Curiger, Stephen N. Grider, David A. Bunsey, James E. Bartling, Shyun Liu, Bradley M. Harrington
  • Patent number: 5831827
    Abstract: A module houses electronic circuitry that comprises a first electrically conductive surface area and a second electrically conductive surface. The first and second electrically conductive surfaces combine to form a substantially token-shaped body. The body has a groove positioned around its perimeter. A probe that has a first end and a second end. A conductive, approximately pointed tip that extends from the first end of the probe and a conductive sleeve extends outward from pointed tip from a location proximate to said first end to a second distance. A first electrical connection contacts the tip and extends from the first end through the probe out the second end. A second electrical connection contacts the sleeve and extends from the first end through the probe out from the second end. A housing that holds an electronic module. The electronic module has a first surface and a second surface.
    Type: Grant
    Filed: February 26, 1997
    Date of Patent: November 3, 1998
    Assignee: Dallas Semiconductor Corporation
    Inventors: Nicholas M. G. Fekete, Elaine J. Gattenby, Michael L. Bolan
  • Patent number: 5829008
    Abstract: A real time clock plus user memory and extra memory integrated in a single circuit with access to the extra memory either by direct addressing or by providing the address as data to specified addresses in the user memory. Further, the user memory has two banks with the same addresses, and bank selection derives from a bit in another portion of the user memory.
    Type: Grant
    Filed: April 30, 1997
    Date of Patent: October 27, 1998
    Assignee: Dallas Semiconductor Corporation
    Inventors: William J. Podkowa, Douglas Scott Bankes
  • Patent number: 5825211
    Abstract: A transmission line sampling circuit for a T1 line is disclosed. A multi phase oscillator is connected to a plurality of state machines which are connected in parallel to a transmission line. The use of a plurality of state machines to sample the transmission line effectively increases the sample rate of the transmission line beyond that which can ordinarily be supported by a single phase oscillator running at the same frequency of the multi phase oscillator. The outputs of the plurality of state machines are provided to an arbitrator and to a MUX wherein the arbitrator decides which of the four state machines outputs should be switched through the MUX and produced transmitted on an output line.
    Type: Grant
    Filed: October 22, 1997
    Date of Patent: October 20, 1998
    Assignee: Dallas Semiconductor Corporation
    Inventors: Michael D. Smith, Michael R. Williamson