摘要 |
An improved spacecraft ordnance system includes a plurality of squibs each connected with a resistor having a squib unique resistance value and a driver unit including built-in test circuitry. Ordnance harness cables connect the squibs with the driver unit. The resistors enable squib identification. The built-in test circuitry enables unambiguous verification of correct connection of each squib with the driver unit. The built-in test circuitry includes a low-impedance multiplexer for selecting a driver line for monitoring, a precision current source for providing a relatively low current to a selected output of the driver unit producing a voltage proportional to the total resistance from signal to ground, and a analog/digital converter for digitizing the voltage and reporting the result to a computer for comparison to predicted values using a telemetry interface and therefore identifying the selected squib. An EMI-tight adapter housing the squib-specific resistor may be attached to the squib.
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