Abstract: An integrated digital circuit is protected from reverse engineering by fabricating all transistors of like conductivity with a common size and geometric layout, providing a common layout for different logic cells, connecting doped circuit elements of like conductivity with electrically conductive doped implants in the substrate rather than metalized interconnections, and providing non-functional apparent interconnections that are interrupted by non-discernable channel stops so that all cells falsely appear to have a common interconnection scheme. The camouflage is enhanced by providing a uniform pattern of metal leads over the transistor array, with a uniform pattern of heavily doped implant taps from the transistors for connection to the leads; undesired tap-lead connections are blocked by channel stops.

Abstract: In an amplifier design for a wide memory architecture, a staging buffer can be integrated with the final stage of a multi-stage sense amplifier. The staging buffer includes a memory latch for storing at least one bit of data. The data is transferred into the staging buffer from memory upon strobing at least one read enable line, and transferred from the staging buffer to a data bus upon strobing at least one write enable line. The data signal is transferred from the memory to the staging buffer at a voltage level lower than the full swing voltage level. The memory architecture produced using this design technique allows for a much lower voltage swing on all of the data lines, thus lowering the power requirements of the circuit.

Abstract: Connections between implanted regions in a semiconductor substrate, such as the sources or drains of adjacent transistors, are made by buried conductive implants rather than upper level metalizations. The presence or absence of a connection between two implanted regions is camouflaged by implanting a conductive buried layer of the same doping conductivity as the implanted regions when a connection is desired, and a field implant of opposite conductivity to the implanted regions when no connection is desired, and forming steps into the substrate at the boundaries of the buried layer or field implant that mask the steps formed between different conductivity regions during a selective etch by a reverse engineer. The masking steps are preferably formed by field oxide layers that terminate at the boundaries of the buried layers and field implants.

Abstract: A wide memory architecture is provided for storing data associated with a vector processor. Additionally, a method for accessing a wide memory architecture is provided. The wide memory architecture includes a memory for storing an array of vector operands. The memory is coupled to a data bus which provides an access pathway connecting the memory to a processor. The wide memory architecture further includes at least one staging buffer disposed between the memory and the processor. The staging buffer is capable of providing intermediate storage of a vector operand upon which a function can be performed by the processor.

Abstract: An integrated digital circuit is protected from reverse engineering by fabricating all transistors of like conductivity with a common size and geometric layout, providing a common layout for different logic cells, connecting doped circuit elements of like conductivity with electrically conductive doped implants in the substrate rather than metalized interconnections, and providing non-functional apparent interconnections that are interrupted by non-discernable channel stops so that all cells falsely appear to have a common interconnection scheme. The camouflage is enhanced by providing a uniform pattern of metal leads over the transistor array, with a uniform pattern of heavily doped implant taps from the transistors for connection to the leads; undesired tap-lead connections are blocked by channel stops.

Abstract: An integrated circuit is protected from reverse engineering by connecting doped circuit elements of like conductivity with a doped implant in the substrate, rather than with a metallized interconnect. The doped circuit elements and their corresponding implant interconnections can be formed in a common fabrication step with common implant masks, such that they have an integral structure with similar dopant concentrations. The metallization above the substrate surface can be designed to provide further masking of the interconnects, and microbridges can be added to span strips of transistor gate material in the interconnect path.

Abstract: An integrated digital circuit is protected from reverse engineering by fabricating all transistors of like conductivity with a common size and geometric layout, providing a common layout for different logic cells, connecting doped circuit elements of like conductivity with electrically conductive doped implants in the substrate rather than metalized interconnections, and providing non-functional apparent interconnections that are interrupted by non-discernable channel stops so that all cells falsely appear to have a common interconnection scheme. The camouflage is enhanced by providing a uniform pattern of metal leads over the transistor array, with a uniform pattern of heavily doped implant taps from the transistors for connection to the leads; undesired tap-lead connections are blocked by channel stops.

Abstract: A complementary pipelined logic circuit includes (a) a logic unit that processes a plurality of complementary inputs into a pair of complementary outputs, (b) a load circuit that is connected to a voltage supply node to establish complementary outputs having a voltage swing greater than the output voltage swing of the logic unit, and (c) a control circuit that interfaces between the logic unit and the load circuit and responds to a clock input by controlling the logic state of the load circuit's outputs in accordance with the logic state of the logic unit's outputs. The load circuit is preferably implemented as a regenerative latching circuit that pulls the output voltage swing up to the full supply voltage value. The logic unit and control circuit are preferably implemented with N-channel devices for high speed and compactness, while the latching load circuit is preferably implemented with P-channel devices to obtain a full scale voltage pullup.