Abstract: An apparatus and method for coupling a test head and probe card in an IC testing system incorporating patterned divider elements (24) disposed between rows of signal conductors (22) to provide matching characteristic impedance values along each row of signal conductors. The divider elements have a patterned conductive layer formed thereon that is electrically connected to ground, and a method for determining a useful pattern is provided. Test dividers (24) fabricated with openings of various size and shape are used to construct transmission lines. The impedance of these lines is measured, and the results are used to interpolate an appropriate opening size and shape to achieve a desired transmission line impedance.

Abstract: An apparatus and method for coupling a test head and probe card in an IC testing system incorporating patterned divider elements disposed between rows of signal conductors to provide matching characteristic impedance values along each row of signal conductors. The divider elements have a patterned conductive layer formed thereon that is electrically connected to ground, and a method for determining a useful pattern is provided.

Abstract: An apparatus and method for coupling a test head and probe card in an IC testing system incorporating patterned divider elements disposed between rows of signal conductors to provide matching characteristic impedance values along each row of signal conductors. The divider elements have a conductive layer formed thereon that is electrically connected to ground. Openings of various shapes and sized are formed in the conductive layer to adjust the characteristic impedance of a corresponding signal conductor. A method for determining the patterning required for characteristic impedance matching is also provided. Test dividers are provided with openings of different size, and characteristic impedance measurements are taken with the various openings aligned to a signal conductor. The size opening is then interpolated to provide a particular characteristic impedance value.

Abstract: A compensated opto-electronic gas sensor system comprises active apparatus utilizing electromagnetic radiation for sensing gas and sealed apparatus utilizing electromagnetic radiation for sensing gas. The sealed apparatus exhibits matched characteristics to the active apparatus and exhibits a sensing sensitivity dependent upon the wavelength of the electromagnetic radiation. The system further includes tunable wavelength source respectively coupled to the apparatus for sensing gas for supplying it with electromagnetic radiation of a selectable wavelength. A computer coupled to at least the sealed apparatus for sensing gas and is responsive to an output thereof for controlling the wavelength of the electromagnetic radiation such that the sealed apparatus for sensing gas exhibits an optimal sensitivity.

Abstract: A system for on-line, concurrent self-testing of a computer is disclosed which is capable of checking the "test kernel" of the computer; that is, the portion of the computer that must be fault-free in order for the computer to test itself with a self-test program. The test kernel includes the computer CPU, the ROM which contains the self-test program, and the intraboard data, address and control buses, bus drivers and multiplexers. The system operates in a transparent fashion to test the computer during its normal operation. The system includes a linear feedback shift register connected to control signal outputs of the CPU and thus determines whether the CPU produces the proper control signals during fetch and/or execution of each program instruction.