Patents by Inventor Steven S. Chan

Steven S. Chan 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: 5442747
    Abstract: A multimedia video processor chip for a personal computer in employs a multi-port central cache memory to queue all the incoming data to be stored in a DRAM and all the outgoing data being retrieved from the DRAM. Such a cache memory is used in one of several modes in which the cache memory is partitioned by cache boundaries into different groups of storage areas. Each storage area of the cache is dedicated to storing data from a specific data source. The cache boundaries are chosen such that, for a given mode, the storage areas are optimized for worst case conditions for all data streams.
    Type: Grant
    Filed: September 27, 1993
    Date of Patent: August 15, 1995
    Assignee: AuraVision Corporation
    Inventors: Steven S. Chan, Miles S. Simpson, Scott A. Kimura
  • Patent number: 5376901
    Abstract: A hermetically sealable millimeter waveguide launch transition feedthrough for channelling high frequency electrical signals in a circuit which includes at least one waveguide. An aperture is formed in one wall of the waveguide and a conductive pin passes through the aperture. The pin is sealed therein by a dielectric material which surrounds the pin so as to isolate it from the waveguide wall. A probe head is disposed at one end of the conductive pin and within the waveguide. The opposite end of the pin contains a second probe head or other circuit connector. The transition may be effectively implemented in waveguide-to-waveguide or waveguide-to-device applications as well as in colinear device housing applications.
    Type: Grant
    Filed: May 28, 1993
    Date of Patent: December 27, 1994
    Assignee: TRW Inc.
    Inventors: Steven S. Chan, Victor J. Watson, Cheng C. Yang, Stuart Kam
  • Patent number: 5336992
    Abstract: An electrical testing device is provided for testing integrated circuits located on a wafer. The testing device employs a multi-layer test circuit having a plurality of contacts for contacting the integrated circuits on a wafer. The layers of the test circuit are embedded in a flexible, supportive dielectric material which allows vertical flexing of the contacts. Cross bar switches are further employed to switch among the plurality of contacts thereby enabling the testing of individual dies of the water to be tested. A microprocessor is further included for controlling the switching and the testing of each die. In an alternate embodiment, the plurality of contacts are mechanically moved relative to the wafer to allow testing of the dies without the need for the switches.
    Type: Grant
    Filed: June 3, 1992
    Date of Patent: August 9, 1994
    Assignee: TRW Inc.
    Inventors: Yoshio Saito, James C. Lau, Steven S. Chan, Richard P. Malmgren
  • Patent number: 5235300
    Abstract: A module package for unpackaged millimeter wave or microwave devices allows the device to be dropped into a cavity formed in a housing and then hermetically sealed therein. Employing dielectric probe members which pass through corresponding slots in the housing to electrically interconnect the device within an application circuit allow for effective hermetic sealing and minimize electrical discontinuities and transmission losses.
    Type: Grant
    Filed: March 16, 1992
    Date of Patent: August 10, 1993
    Assignee: TRW Inc.
    Inventors: Steven S. Chan, D. Ian Stones
  • Patent number: 4859870
    Abstract: A CMOS driver circuit for integrated circuits capable of operating in two modes. The first, high speed, mode allows the driver circuit on an integrated circuit device to drive the internal signals of the device to the outside world for standard operation of the integrated circuit devices. The second mode causes the driver circuit to behave as a weak driver for easily testing the integrated circuit.
    Type: Grant
    Filed: January 9, 1989
    Date of Patent: August 22, 1989
    Assignee: LSI Logic Incorporated
    Inventors: Anthony Y. Wong, Daniel Wong, Steven S. Chan
  • Patent number: 4845390
    Abstract: A circuit (40) constructed in accordance with this invention includes a ring oscillator (25) to provide a signal which is dependent on the propagation delays of the inverters (33, 34, 35) comprising the ring oscillator, therefore the frequency of the ring oscillator is inversely dependent upon the propagation delays of the inverter comprising the ring oscillator. Means (37) are provided to determine the propagation delay introduced by the components in the ring oscillator by measuring the frequency of the output signal produced by the ring oscillator which provides a signal to a multiplexer (36) which selects among a number of preset delay components (26) those components which are necessary to ensure that the propagation delay caused by the circuitry (not shown) connected to the input lead (21) of the circuit constructed in accordance with this invention plus the propagation delay introduced by the selectable delay elements is nearly a constant propagation delay.
    Type: Grant
    Filed: January 11, 1988
    Date of Patent: July 4, 1989
    Assignee: LSI Logic Corporation
    Inventor: Steven S. Chan
  • Patent number: 4737670
    Abstract: A circuit (40) constructed in accordance with this invention includes a ring oscillator (25) to provide a signal which is dependent on the propagation delays of the inverters (33, 34, 35) comprising the ring oscillator, therefore the frequency of the ring oscillator is inversely dependent upon the propagation delays of the inverter comprising the ring oscillator. Means (37) are provided to determine the propagation delay introduced by the components in the ring oscillator by measuring the frequency of the output signal produced by the ring oscillator which provides a signal to a multiplexer (36) which selects among a number of preset delay components (26) those components which are necessary to ensure that the propagation delay caused by the circuitry (not shown) connected to the input lead (21) of the circuit constructed in accordance with this invention plus the propagation delay introduced by the selectable delay elements is nearly a constant propagation delay.
    Type: Grant
    Filed: November 9, 1984
    Date of Patent: April 12, 1988
    Assignee: LSI Logic Corporation
    Inventor: Steven S. Chan
  • Patent number: 4584556
    Abstract: In a system for comparing the ratio of two numbers to a threshold, the bits of each number are compared in groups comprising less than the total number of bits. The most significant group of bits are first compared, and if they contain sufficient information to make the comparison, the result thereof is indicated. If the most significant group of bits does not contain sufficient information, the comparison is made based upon the next higher order group of bits that does contain sufficient information. In some situations, it is desirable to obtain information about the next lower order group of bits in order to verify whether a determination is correct. Each of these situations has a unique address in a memory unit dedicated to the next lower order group of bits.
    Type: Grant
    Filed: December 21, 1984
    Date of Patent: April 22, 1986
    Assignee: Ampex Corporation
    Inventor: Steven S. Chan
  • Patent number: 4500933
    Abstract: A universal interface unit for providing output signals in any one of a plurality of different signal formats stores information relating to each of the different available formats. When signals are to be provided to a particular device, personality data regarding the device enables the particular signal format requirements of the device to be read from the stored information. A signal processor responsive to this information generates output signals in that format. The output signals are transmitted to the device through a switching circuit that is appropriately connected to the device to provide the proper polarity.
    Type: Grant
    Filed: April 2, 1982
    Date of Patent: February 19, 1985
    Assignee: Ampex Corporation
    Inventor: Steven S. Chan
  • Patent number: 4462051
    Abstract: To decode a binary signal without regard to the speed at which it is read, each transition in the binary signal is detected, and the time lapse between successive transitions is determined to thereby establish the length of a pulse in the binary signal. The length of one pulse is compared with that of the immediately preceding bit cell to determine whether their lengths are approximately the same or vary by a factor of approximately 2. If the two compared lengths are approximately the same, it is recognized that there is no change in the information conveyed by the signal and therefore the binary state of the most recently detected pulse is representative of the previously established binary state of the signal. However, if the pulse has a duration of approximately one half that of the preceding bit cell, a change in the state of the binary information being conveyed is recognized, and an appropriate indication is provided to signal such change.
    Type: Grant
    Filed: April 2, 1982
    Date of Patent: July 24, 1984
    Assignee: Ampex Corporation
    Inventor: Steven S. Chan
  • Patent number: 4040100
    Abstract: The picture frames recorded on video magnetic tape are identified by serial binary numbers magnetically recorded along an edge of the tape. The sequential ONE and ZERO bits that form each number occur during equal successive intervals when the tape is transported at constant speed and these bits are detected as electrical pulse excursions, one pulse excursion during the interval for a ONE and no excursions during an interval for a ZERO. The pulses are detected even while the tape is not transported at constant speed as when it is accelerating or decelerating and so, the intervals for the successive binary bits may change rapidly and when that occurs, it is difficult to determine whether the successive excursions define a binary ZERO interval or the first half of a binary ONE interval and so, it cannot be determined whether they represent a binary ONE or a binary ZERO.
    Type: Grant
    Filed: September 25, 1975
    Date of Patent: August 2, 1977
    Assignee: Adams-Smith Incorporated
    Inventor: Steven S. Chan