Honeywell Advanced Circuits, Inc.

Yutaka Doi

Stephen Tisdale

Methods and devices for testing connectivity between connectors on a circuit board include utilizing a bias board having a photoconductive layer coated with a light-transmissive electrically conductive layer in conjunction with a light source and a voltage source to alternately charge and discharge conductors. A conductor discharged by connecting it to a ground via the bias board is determined to be electrically connected to a previously charged conductor if current flows between the conductor and the ground.

Fixture-less bare board tester

Measurement of the permittivity of thin films is facilitated through the use of a short cylindrical metal cavity containing parallel plates between which a specimen to be measured is placed. The use of such parallel plates contained within such a cavity is particularly advantageous when swept frequency measurement methods utilizing frequency ranges from to GHz are employed. A test fixture which is preferred for use in providing such a cavity is disclosed as are methods of using the test fixture.

Permittivity measurement of thin films

Compositions and methods are provided whereby printed wiring boards may be produced that comprise a) a substrate layer, and b) a hollow, mirror-clad optical wave-guide laminated onto the substrate layer. The printed wiring board further comprises a cover material coupled to the wave-guide.

Layered circuit boards and methods of production thereof

Methods and apparatus for improved impedance measurements are which allow for shorter delays during recalibration and which eliminate the need to physically disconnect and reconnect test leads after initial calibration has been completed. In particular, an adjustment factor is calculated based on impedances measured during initial calibration and is used to adjust future impedance measurements. Moreover, a plurality of loads having pre-measured impedances are switchably connected to the meter such that re-calibration using said loads may be accomplished without the physical connection or disconnection of test leads. The plurality of loads are preferably incorporated into a test board which also comprises additional test leads and a switching mechanism to alternately connect the various loads and test leads to the meter.

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Minnetonka, MN, United States of America

Yutaka Doi