The purpose of the HDI Cable Tester is to insure that no cable assembly
or terminator card defects exist in a newly interconnected HDI Assembly
just prior to initial powerup. The system functions to test the power
cable and the signal cables which route between the matching card and
the HDI by way of the terminator board. The test system consists of a
matching card crossconnect switch board,
a National Instruments DAQ500 data acquisition board plugged into a
laptop computer running LabVIEW 5.0. A graphical virtual instrument
interface provides the test system control and readout. The pc card is housed in a protective aluminum case.
The two HDI Matching Card cables connect to the 5" x 12" switch board with each of the 50 signal lines routing to a pair of MAXIM MAX395 serially controlled 8-Channel SPST switches. Each switch pair accomdates eight different matching card signals. The swiching scheme provides for resistance testing between any pair of signals. A 700 mV signal is applied to the selected pair and the circuit is completed through one of five different multiplier resistors. Seperate 12 bit A/D converter inputs are provided across each of the multiplier resistors set to measure +-5.00 vdc.
A preliminary version of the LabVIEW driver program generates the serial data stream along with a clock and the MAX395 chip select signals.
(Written 2/11/1999, edited 6/8/04 by SB)