Abstract: A fiber optic cable is provided with a thermal shield which consists (proceeding outward from the cable) of a temperature insulating layer of a foam plastic such as polyethylene, a plastic film wrap such as aluminized nylon, a metallic braid such as tinned copper and an outer jacket of plastic as additional temperature insulation and to facilitate pulling the cable. The film wrap and outer jacket are optional. For further shielding a second layer of foam plastic may be positioned outside the first metallic braid followed by a second plastic film wrap, a second metallic braid and an outer plastic jacket. If the shielded cable is near a source of heat, such as a hot water pipe or an air conditioning duct, the fiber optic cable temperature is uniform throughout its cross-section. Without the thermal shield instability of the signals in different fibers may occur because of heat differential.

Abstract: A method and apparatus are presented for removing one or more covers of an electronic module. The electronic module includes a cover extending over semiconductor devices mounted upon a substantially planar surface of the substrate. The cover is attached to the surface of the substrate about the semiconductor devices by an adhesive layer. The method includes bringing a cutting blade into contact with the cover and the adhesive layer such that the adhesive layer and a portion of the cover adjacent to the adhesive layer are substantially removed. During the cover removal procedure, a bottom surface of the cutting blade may be moved in a plane parallel to the substantially planar surface of the substrate. One embodiment of the apparatus includes a cutting tool having a cutting blade, a base plate, and a fixture adapted for holding the module.

Abstract: An apparatus and method are provided for bit synchronization in an optical time division multiplexed communication system. The apparatus is couplable to an optical gate, such as an optical demultiplexer. The apparatus includes a programmable optical delay line couplable to an input clock; an optical synchronizer coupled to the programmable optical delay line and couplable to the optical gate; and a processor coupled to the programmable optical delay line and to the optical synchronizer. The processor includes program instructions to track bit synchronization between a clock pulse and a selected data bit during a communication session; and when a bit tracking range is approaching a predetermined limit, the processor having further instructions to interrupt the communication session, return the bit tracking range to a zero offset and correspondingly adjust a programmable delay, and resume the communication session.

Abstract: Heat emitting electrical components are encased in a refrigerated package within a housing which may be under vacuum. Power for the components is supplied through a transformer within the vacuum housing, the secondary of which is in thermal contact with the package and has heat transmitting electrical connections to the components. To reduce conduction or convection of heat from the primary of the transformer to the refrigerated package, a small gap of about 1 mil is provided. For pot core transformers the core may be split, with the gap between the split portions. For toroidal transformers, the secondary is spaced from the primary as well as from the core by such gap.

Abstract: To cool heat-emitting electronic components, a compact, non-moving-parts compressor, an evaporator in juxtaposition to the electronic components and a condenser are mounted as a unit, preferably within a vacuum can. A heat exchanger is mounted external to the can but in proximity to the condenser. The foregoing comprise a unit which may be detachably connected to a host pump and heat exchanger. The unit may be removed from the system of which it is a part for upgrade and maintenance. All its components are thermally isolated from the ambient atmosphere to prevent water vapor condensation corrosion.

Abstract: A process for fabricating a composite material such as that having high thermal conductivity and having specific application as a heat sink or heat spreader for high density integrated circuits. The composite material produced by this process has a thermal conductivity between that of diamond and copper, and basically consists of coated diamond particles dispersed in a high conductivity metal, such as copper. The composite material can be fabricated in small or relatively large sizes using inexpensive materials. The process basically consists, for example, of sputter coating diamond powder with several elements, including a carbide forming element and a brazeable material, compacting them into a porous body, and infiltrating the porous body with a suitable braze material, such as copper-silver alloy, thereby producing a dense diamond-copper composite material with a thermal conductivity comparable to synthetic diamond films at a fraction of the cost.

Abstract: An apparatus and method are provided for bit synchronization in an optical time division multiplexed communication system. The apparatus is couplable to an optical gate, such as an optical demultiplexer. The apparatus includes a programmable optical delay line couplable to an input clock; an optical synchronizer coupled to the programmable optical delay line and couplable to the optical gate; and a processor coupled to the programmable optical delay line and to the optical synchronizer. The processor includes program instructions to track bit synchronization between a clock pulse and a selected data bit during a communication session; and when a bit tracking range is approaching a predetermined limit, the processor having further instructions to interrupt the communication session, return the bit tracking range to a zero offset and correspondingly adjust a programmable delay, and resume the communication session.

Abstract: Cooling liquids such as fluorocarbons are enclosed within a module containing electronic components on a printed wiring board. Preferably top and bottom covers are applied to the top and bottom of the board and liquid-sealed thereto. Hot-melt adhesive is used for the seal. Each edge of a top cover has an outward-extending flange formed with a peripheral downward turned lip. Heated adhesive is applied to the cover in a continuous bead around the flange, the thickness of the bead being greater than the height of the lip. The cover is then squeezed against the board so that the adhesive seals against the board and the flange. The bottom cover is formed in complementary fashion.

Abstract: An integrated circuit and associated method for reducing total signal propagation delay as well as power consumption and thermal dissipation. The integrated circuit comprises a plurality of active layers coupled together in close proximity. In order to produce the integrated circuit, at least two active layers are removed from their respective substrate after integrated circuit processing. Some of the methods that may be used include Silicon on Insulator ("SOI") and epitaxial etch stop ("EES") processes. After removal of the active layers, at least one via is implemented on a bottom surface of each active layer in order to establish a mechanical and electrical connection between the via and its associated metal interconnects. Thereafter, the active layers are coupled together by ultrasonic welding or through nitride lamination using Titanium Nitride for conductive regions and Silicon Nitride for insulative regions.

Abstract: A signal communication device for use within a computer includes a set of optical fibers configured to form an optical computer bus between a set of computer sub-system elements of a computer. A set of input optical connector cards are connected to the set of optical fibers. Each of the input optical connector cards includes a transmitting dynamic bandwidth allocator responsive to an optical bus clock signal operating at a multiple of a computer system clock signal such that a set of bus time slots are available for each computer system clock signal cycle. The transmitting dynamic bandwidth allocator allows a light signal to be applied to the optical computer bus during a dynamically assigned bus time slot. In this way, the optical computer bus bandwidth can be dynamically allocated to different computer sub-system elements during a single computer system clock signal cycle.

Abstract: A method and apparatus for cooling an integrated circuit device mounted face-down on a package such that the device may be optically probed. The method of the present invention includes the following steps: (1) placing an optically-transparent window over the integrated circuit device to form a channel bounded by the optically-transparent window and the integrated circuit device and (2) flowing an optically-transparent fluid through the channel to remove heat dissipated by the integrated circuit device.

Abstract: To cool heat-emitting electronic components, a compact, non-moving-parts compressor, an evaporator in juxtaposition to the electronic components and a condenser are mounted as a unit, preferably within a vacuum can. A heat exchanger is mounted external to the can but in proximity to the condenser. The foregoing comprise a unit which may be detachably connected to a host pump and heat exchanger. The unit may be removed from the system of which it is a part for upgrade and maintenance. All its components are thermally isolated from the ambient atmosphere to prevent water vapor condensation corrosion.

Abstract: A fiber optic cable is provided with a thermal shield which consists (proceeding outward from the cable) of a temperature insulating layer of a foam plastic such as polyethylene, a plastic film wrap such as aluminized nylon, a metallic braid such as tinned copper and an outer jacket of plastic as additional temperature insulation and to facilitate pulling the cable. The film wrap and outer jacket are optional. For further shielding a second layer of foam plastic may be positioned outside the first metallic braid followed by a second plastic film wrap, a second metallic braid and an outer plastic jacket. If the shielded cable is near a source of heat, such as a hot water pipe or an air conditioning duct, the fiber optic cable temperature is uniform throughout its cross-section. Without the thermal shield instability of the signals in different fibers may occur because of heat differential.

Abstract: A computer bus includes a set of computer bus input nodes to receive a set of computer bus input signals generated by system cards attached to the computer bus. The computer bus input signals are processed by a set of bus bit processors. Each of the bus bit processors includes a digital gate logic circuit to perform a logical OR operation on a subset of the set of computer bus input signals. The subset of computer bus input signals corresponds to the signals carried by a single line of a traditional computer bus. Each bus bit processor generates a bus bit processor output signal. The set of bus bit processors thereby form a set of bus bit processor output signals. The bus bit processor output signals are applied to computer bus output nodes for processing by the system cards in a conventional manner. Thus, the digital gate logic circuits of the bus bit processors execute the function performed by traditional hardwired computer bus structures.

Abstract: An open fiber safety interlock that disables the light transmitter whenever the cable is disconnected or broken. In one embodiment, a cable containing an optical fiber and an electrical conductor is coupled between a local receiver and a remote transmitter. The remote transmitter transmits a light signal to the local receiver via the optical fiber. The power for the remote transmitter is provided to the remote transmitter via the electrical conductor from a local power supply. Disconnecting or breaking the cable results in a loss of power to the transmitter, thereby halting any further light emissions. Broadly speaking, the present invention contemplates a remote module which implements an open fiber safety interlock. The remote module comprises a transmitter for transmitting light through an optical fiber in a cable, where the cable includes an electrical conductor.

Abstract: An integrated circuit and associated method for reducing total signal propagation delay as well as power consumption and thermal dissipation. The integrated circuit comprises a plurality of active layers coupled together in close proximity. In order to produce the integrated circuit, at least two active layers are removed from their respective substrate after integrated circuit processing. Some of the methods that may be used include Silicon on Insulator ("SOI") and epitaxial etch stop ("EES") processes. After removal of the active layers, at least one via is implemented on a bottom surface of each active layer in order to establish a mechanical and electrical connection between the via and its associated metal interconnects. Thereafter, the active layers are coupled together by ultrasonic welding or through nitride lamination using Titanium Nitride for conductive regions and Silicon Nitride for insulative regions.

Abstract: An integrated digital light modulator. In one embodiment, a light beam is split into a set of binary weighted beams which are then individually switched on or off by an optical switch. The weighted beams which are conveyed by the optical switches are then recombined to produce a modulated beam. In this manner, a fast inexpensive integrated digital light modulator may be advantageously obtained. Broadly speaking, the present invention contemplates a digital optical power modulator that comprises a binary power divider and an optical modulator. The binary power divider is configured to receive an input light beam and split it into a set of weighted beams. The optical powers of the weighted beams are related in that the ratio of the optical powers of any two weighted beams is substantially an integer power of two. The optical modulator receives the set of weighted beams from the binary power divider and receives a digital signal.

Abstract: A process for fabricating a composite material such as that having high thermal conductivity and having specific application as a heat sink or heat spreader for high density integrated circuits. The composite material produced by this process has a thermal conductivity between that of diamond and copper, and basically consists of coated diamond particles dispersed in a high conductivity metal, such as copper. The composite material can be fabricated in small or relatively large sizes using inexpensive materials. The process basically consists, for example, of sputter coating diamond powder with several elements, including a carbide forming element and a brazeable material, compacting them into a porous body, and infiltrating the porous body with a suitable braze material, such as copper-silver alloy, thereby producing a dense diamond-copper composite material with a thermal conductivity comparable to synthetic diamond films at a fraction of the cost.

Abstract: An array of termination resistors has symmetrical geometry producing essentially no net magnetic field and a resultant low inductance is fabricated on a substrate as disk resistors. Conductive through vias are formed in the substrate in an array pattern defining what will be resistor first and second contacts. Each disk resistor has one first contact located at the resistor disk center, and preferably four second contacts located symmetrically about the resistor disk and shared by four adjacent disk resistors. For each resistor, a annular-shaped disk of resistive material is fabricated on a first surface of the substrate, such that a central opening in the disk overlies at least the upper surface of a first contact via. The disk geometry and material determines its resistance. Next, a layer of conductive material is formed over the first surface of the substrate to cover at least the periphery of each disk, and to fill the central opening in each disk.

Abstract: A method and apparatus for providing address designations for a three dimensional computer system arranged in a plurality of planar layers is disclosed. Each layer comprises an incrementer for generating a layer identification value. A first layer has a starting value, representing the first layer identification value, and an incremental value which is added to the starting value to generate a second layer identification value. In this way, each incrementer on each layer is serially coupled to a next higher layer. A control processor accesses file information on each layer through use of the layer identification value. The register file identifies the layer as a memory module, processor module or input/output interface module. From the information contained within the register file, the control processor assigns an address to each of the layers. In addition, the control processor writes initialization parameters to the register file.