Patents by Inventor Warren J. Schultz

Warren J. Schultz 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: 5675268
    Abstract: An overcurrent detector circuit (21) for a power MOSFET (22) is described. The overcurrent detector circuit (21) generates a bias voltage corresponding to the drain to source voltage of the power MOSFET (22). The drain to source voltage correlates directly to the current being conducted by the power MOSFET (22). An overcurrent condition occurs when the power MOSFET (22) exceeds a predetermined current. The bias voltage is applied to a transistor (24) for generating a current. A current source (29) couples to the transistor (24). The current provided by the transistor equals the reference current of the current source (29) when the power MOSFET conducts the predetermined current. The overcurrent detector circuit (21) generates a signal indicating a overcurrent condition does not exist when the reference current is greater the current provided by the transistor.
    Type: Grant
    Filed: October 3, 1995
    Date of Patent: October 7, 1997
    Assignee: Motorola, Inc.
    Inventors: Thomas D. Petty, Troy L. Stockstad, Warren J. Schultz
  • Patent number: 5563437
    Abstract: A large sense voltage is produced by the semiconductor device of the present invention. The semiconductor device, utilizing current mirror techniques, is comprised of a power MOSFET having a plurality of power cells and a plurality of sense cells formed in a semiconductor epitaxial layer. The large sense voltage is provided by isolating and separating the plurality of power cells from the plurality of sense cells by at least the thickness of the semiconductor epitaxial layer. Isolation can be provided by forming a plurality of inactive cells or an elongated cell between the plurality of power cells and the plurality of sense cells. In addition, high voltage capabilities can be maintained by including a partially active region adjacent the power cells to provide for good termination.
    Type: Grant
    Filed: February 21, 1992
    Date of Patent: October 8, 1996
    Assignee: Motorola, Inc.
    Inventors: Robert B. Davies, Warren J. Schultz
  • Patent number: 5351549
    Abstract: A pulsed pressure sensor circuit (11) with increased sensitivity for measuring low pressures. A pulse generation circuit (12) is enabled by a microprocessor (28) to output a voltage pulse. The voltage pulse biases a pressure sensor (17) which has a port exposed to a pressure to be sensed. The pressure sensor (17) outputs a differential voltage which is proportional to the pressure at the port. The differential voltage is amplified by an amplifier (23) which has an output coupled to the microprocessor (28). A voltage divider circuit (26) is coupled to the pulse generation circuit (12) and has an output coupled to the microprocessor (28). The microprocessor (28) samples the voltages at the output of the amplifier (23) and the output of the voltage divider circuit (26). Microprocessor (28) then calculates the pressure using the sampled voltages and data stored in memory.
    Type: Grant
    Filed: October 1, 1992
    Date of Patent: October 4, 1994
    Assignee: Motorola, Inc.
    Inventors: Jeffrey Baum, Warren J. Schultz
  • Patent number: 5327016
    Abstract: A control circuit for switching AC or DC loads and for automatically discerning the presence of an AC or a DC power supply via a switch has been provided. The control circuit is coupled to alternately render a switch operative and non-operative wherein the switch is coupled across a load which is powered up by either an AC or a DC power supply. The control circuit includes an AC/DC discernment circuit for ascertaining whether the load is powered up by an AC or a DC power supply. The control circuit also includes circuitry for comparing signals sensed by the switch with predetermined thresholds (which are a function of whether an AC or DC determination has been made) for providing logic signals to control the operation of the switch.
    Type: Grant
    Filed: April 6, 1992
    Date of Patent: July 5, 1994
    Assignee: Motorola, Inc.
    Inventors: Stephen Su, Warren J. Schultz, Lloyd Hayes
  • Patent number: 5299460
    Abstract: A circuit for a pulse width modulating a sensor (12) has been provided. The circuit includes a first switch (22) for alternately coupling the sensor between first and second supply voltage terminals. The circuit also includes second (24) and third (28) switches and first and second capacitors for sampling the differential voltage appearing at outputs of the sensor when the first switch is in a closed state.
    Type: Grant
    Filed: February 24, 1992
    Date of Patent: April 5, 1994
    Assignee: Motorola, Inc.
    Inventors: Warren J. Schultz, Denise M. Williams
  • Patent number: 5155450
    Abstract: A circuit for interfacing with the outputs of a differential pressure sensor provides a single-ended output voltage translated in voltage level with respect to the differential voltage applied thereto from the sensor while cancelling the common mode offset voltage of the sensor so that the output voltage is independent of the common mode offset voltage. The circuit includes four operational amplifiers arranged as a differential-to-single ended converter with gain.
    Type: Grant
    Filed: December 23, 1991
    Date of Patent: October 13, 1992
    Assignee: Motorola, Inc.
    Inventor: Warren J. Schultz
  • Patent number: 5119000
    Abstract: A normally non-conducting motor drive transistor is connected in parallel with a freewheeling diode. The transistor is briefly enabled while reverse recovery transition current is flowing in the freewheeling diode and thereby reduces noise created by the diode when it switches from conducting reverse recovery current to blocking reverse voltage.
    Type: Grant
    Filed: February 25, 1991
    Date of Patent: June 2, 1992
    Assignee: Motorola, Inc.
    Inventor: Warren J. Schultz
  • Patent number: 4967336
    Abstract: A high voltage bridge interface circuit is provided for AC and brushless DC motor control having a high voltage isolation circuit and drive circuits which simplify the high voltage interface and reduce the total system integration effort. The isolation circuit provides the high voltage unilateral isolation between the control circuit and the high voltage power supply conductors, while the drive circuits improve the noise immunity at the gate termimals of the power MOSFET bridge. The high voltage bridge interface circuit is partitioned by providing the high voltage interface within one IC thereby permitting the integration of the discrete components of the power MOSFET drive circuits and simplifying the overall system integration.
    Type: Grant
    Filed: February 26, 1990
    Date of Patent: October 30, 1990
    Assignee: Motorola, Inc.
    Inventors: Robert B. Davies, Warren J. Schultz, James J. Stipanuk
  • Patent number: 4897580
    Abstract: A transformer coupled amplifier drive circuit (60) and method especially suited for providing a saw-tooth current waveform to an inductive load (32) for horizontal deflection applications in CRT monitors and the like are described. The transformer primary (48) is coupled between the power source connection (11) and the input of the amplifier (26) while the transformer secondary (50) has an opposite polarity terminal coupled to the input of the amplifier (26) through an inductor (52) and the other terminal of the secondary (50) coupled to the common terminal (15) of the amplifier (26) through a diode (56).When the input switch (44) is closed, the input of the amplifier (26) is energized by a current (65) through the series connected primary (48) and energy is stored in the transformer magnetizing field and in the amplifier (26). Conduction in the transformer secondary (50) is blocked by the diode (56).
    Type: Grant
    Filed: June 20, 1989
    Date of Patent: January 30, 1990
    Assignee: Motorola Inc.
    Inventor: Warren J. Schultz
  • Patent number: 4698655
    Abstract: An overvoltage and overtemperature protection circuit that includes an output thyristor fabricated in monolithic integrated circuit form is provided. The thyristor comprises a P-type substrate serving as an anode and diffused cathode and gate region wherein the current flows vertically, optimizing the high voltage and high current capability. A thermal limit circuit is provided for triggering the thyristor when a designated temperature is exceeded. The output thyristor will shunt the output voltage to ground whenever the predetermined voltage or temperature is exceeded.
    Type: Grant
    Filed: February 4, 1986
    Date of Patent: October 6, 1987
    Assignee: Motorola, Inc.
    Inventor: Warren J. Schultz
  • Patent number: 4599548
    Abstract: A PWM controller for an electrical utilizes a dual differential input topology comprising two input comparators deriving a proportional reference from two potentiometers for providing a variable pulse width modulated output. The pulse width modulation controller of the present invention does not require scaling and may be utilized in appliances, robotics, toys and in conjunction with other electromechanical and electrical loads.
    Type: Grant
    Filed: March 18, 1985
    Date of Patent: July 8, 1986
    Assignee: Motorola Inc.
    Inventor: Warren J. Schultz
  • Patent number: 4562454
    Abstract: A semiconductor fuse is disclosed that provides protection against both overcurrent and the abrupt application of a voltage to semiconductor devices. A first means is coupled to an input terminal for providing a signal when a current is applied to the input terminal. A second means is coupled between the input terminal and an output terminal for allowing current to pass therebetween and is coupled to the detecting means and responsive to the signal. A third means is coupled between the output terminal and a ground terminal for shorting a current therebetween. A fourth means is coupled to the input terminal, the second means, and the third means for activating the third means and preventing the second means from responding to the signal when the input current exceeds a predetermined value.
    Type: Grant
    Filed: December 29, 1983
    Date of Patent: December 31, 1985
    Assignee: Motorola, Inc.
    Inventors: Warren J. Schultz, Herbert A. Saladin