Abstract: A fault insertion circuit is disclosed which generates and applies a fault signal to a digital circuit under test. The fault insertion circuit includes fault insertion hardware connected to the digital circuit under test. The fault insertion hardware is arranged to select, generate and apply the fault signal. A programmable controller and communication circuit are also included. The communication circuit is connected to the controller and to a data terminal, personal computer or any other source of programming commands and instructions. The communication circuit receives the programming commands and instructions from the data terminal and transmits the commands and instructions to the controller. The controller in response to the received commands and instructions transmits control signals to the fault insertion hardware, thereby, generating and applying a fault signal to the digital circuit under test.

Abstract: A drill collar position verifier is disclosed for use with a drill bit having a drilling depth control collar positioned coaxially thereon. The drill bit is inserted in a cylindrical opening in a plastic block to a depth determined by the position of the collar. A metallic foil and membrane switch are positioned below the plastic block of predetermined depth and are connected to logic circuitry which is further connected to LED indicators. If the drill bit does not protrude through the plastic block, an LED is lit to indicate that the collar is positioned too close to the tip of the drill bit. If the drill bit protrudes through the fixture and contacts the foil only, an LED is lit to indicate that the collar is positioned within tolerances. And, if the drill bit protrudes through the fixture and contacts both the foil and the membrane switch, an LED is lit to indicate that the collar is positioned too far away from the tip of the drill bit.

Abstract: A thermal management plate designed to take advantage of the thermally conductive path provided as an integral part of printed circuit board component assemblies. The plate is a shelf-like unit providing both thermal management of electronic assemblies and a mounting arrangement for assemblies. Manufactured of high conductive material, the unit includes a printed circuit board assembly locator, a thermal path and a series of finned surfaces on the front and rear to dissipate heat generated by components.

Abstract: An improved method of tape automated bonding that makes use of a "universal" tape to accommodate integrated circuit chips having different bonding site patterns. The tape comprises a series of parallel continuous thin metal beam lead conductors fixed to a flexible plastic substrate. Two such tapes are disposed at right angles to each other forming in effect a square matrix of beam lead conductors. Each tape site is custom trimmed to match the bonding pad locations of each different integrated circuit chip.

Abstract: A test probe for use with a chip carrier socket including electrical connections to an external testing device and contacts to engage matching contacts within the chip socket. Tong-like elements grasp the socket to insure both mechanical and electrical integrity of the connections. A slip ring retains the tongs and probe in operated position.

Abstract: A method to mount and cool integrated circuit chips within a multilayer printed wiring board structure. The method makes the use of tape automated bonding or flip chip dice attachment techniques in such a way that a cavity may be formed above and below the integrated circuit which will serve as a passage way for cooling.

Abstract: A tool for repairing an improperly positioned surface mounted component on the printed circuit board consisting of a body portion with a pair of legs positioned relative to the component mounting area on the printed circuit board with an included vacuum mechanism used to seize the component and reposition it against locating cams included in a pair of vertical legs.

Abstract: Eutectic solder, including a combination of tin, lead and silver is doped by the addition of copper to substantially improve its effectiveness in soldering printed wiring cards which have been screen printed with conductors and mounting pads for components, with a low temperature, thick film cermet copper conductor. The addition of the copper substantially improves wetting and increases long term solder joint reliability.

Abstract: The addition of registration marks as an aid in projecting a precision location of a screened artwork or master pattern as used in printing of thick film circuits on a ceramic substrate base is taught by the present invention. The marks are located in a number of locations on the artwork that correspond to a location which will be determined as the edge of the substrate base when the substrate base is printed in proper registration on the artwork to which the registration marks have been added.

Abstract: A tool adapted to facilitate the removal of elements such as pin grid arrays, pin grid array sockets, chip carriers, and chip carrier sockets which have been soldered into plated through holes or similar elements of printed wiring cards. A platform is provided mounting two pivotable arms which are used to grip onto the element to be removed while a number of spring loaded posts are compressed to provide connection to the printed wiring card on which the element to be removed is attached. The entire assembly is then placed in a high temperature environment causing the solder to melt at which time the compressed springs, associated with the posts, effectively expand withdrawing the element from the printed wiring card.

Abstract: Thick film resistors are fabricated for use in hybrid microcircuits by a sequence of steps beginning with the formation of a dielectric substrate on a carrier substrate. The dielectric layer is then baked to provide an appropriate rigidity after which a resistance element is deposited thereon as well as conductive terminals, the subsequent firing of both materials followed by heating of the entire assembly to a point where the adhesive characteristics of the dielectric layer are substantially reduced and the resultant film resistors become separated from the carrier substrate.

Abstract: A tool adapted to assist in the placement of dual in-line packaged circuits (DIPs) into printed circuit board sockets. The tool includes a channel-shaped body having parallel sides of a springlike material each side having a gripper jaw attached to the lower edge thereof to grasp and support a dual in-line packaged circuit. A manually operated piston operates to force a DIP circuit which is properly oriented to the socket, into the appropriate location with the leads from the circuit placed in proper engagement with a printed circuit board socket. Operation of the piston also in addition to properly placing the circuit, also automatically disengages the tool from the circuit after placement has been effected.

Abstract: A printed circuit board inspection fixture adapted to support a printed circuit board and including a light source and a mirrored reflective surface positioned to reflect light from the source onto the bottom side of said printed circuit board in order to facilitate inspection of the lower portion so as to detect improper lead insertion of components positioned on the circuit board.

Abstract: A two-piece rotating contact zero insertion force connector is used to interconnect printed circuit boards (daughter boards) to backplanes (mother boards), cables to panels or cables to cables. This is accomplished by rotating one-half of the mating contacts relative to the other half to complete the necessary electrical connection. A number of different rotating contact designs are included which could be utilized to implement the overall concept.

Abstract: A compliant pad or work piece for use in bonding the inner leads of integrated circuit devices as a part of a tape automated bonding process. The work piece is constructed of a metallic base layer to which is affixed a compliant pad, a cap support and a cap positioned on said compliant pad surrounding a gas channel which is connected to a source of gas such as nitrogen. A ceramic heat distribution layer is positioned over said gas channel and acts to support the integrated circuit device to be bonded to an associated tape during the tape automated bonding process.

Abstract: The Arbitrated Bus Interface (ABI) is a set of custom LSI circuits which sends and receives minipackets of binary information to and from a data bus. The ABI performs arbitration, address recognition, and buffering required for transmitting and receiving mini-packets of information between the local packet bus and a microprocessor.

Abstract: A mounting arrangement for printed circuit boards where electrical and mechanical connection is maintained by the characteristics of the contacts included in the connector. While support is provided for the printed wiring board, no retenion means other than the contacts themselves are employed. The combination of a rigid and a flexible contact inhibits "walking" of the board due to vibration.

Abstract: The Mini Packet Receiver Transmitter Circuit (MPRT) provides an interface between one or two eight bit microprocessors and a digital subscriber loop interface circuit. The bi-directional communication on a single wire pair is accomplished by alternating the subscriber loop receive and transmit frames controlled by a "Ping-Pong Protocol" using fixed frame format and bipolar alternate mark inversion (AMI) line encoding. There are two microprocessor ports within the MPRT, a transparent port for voice transmission and a non-transparent port for data trasmission. The MPRT implements the Mini Packet Protocol frame format as a mini packet (MP) of information, for both transparent and non-transparent data.

Abstract: The Asynchronous Packet Manager is the interface for transferring data in a first format between a data terminal equipment and a combination data and telephone switching system in a properietary packet format. A microprocessor accepts data from a universal asynchronous receiver transmitter and forwards the data to a mini packet receiver transmitter, when it is formatted into mini packets and converted to an alternate mark inversion signal and sent to the switching network.

Abstract: The Synchronous Packet Manager is the interface for switching synchronous data between a data terminal equipment and a combination data and telephone switching system in a proprietary packet format. A first microprocessor controlled circuit controls data to be received from the switching system or forwarded to it and communicates with a second microprocessor controlled circuit for controlling data to or from a terminal equipment via a common memory.