摘要 |
<p>Apparatus and method identify and measure random contact interruption events in a circuit interconnection device. A comparator circuit (41), adapted to be operated at high frequencies, identified when an interrupt even has occurred. The comparator circuit, as a result of the interruption event, causes a high frequency counter circuit (44-46) to count clock pulses. The count in the (clock) counter circuit is continuously applied to an RAM memory circuit (51-55), write-enabled at an addressed memory location. After the interrruption event is terminated, the RAM memory circuit (51-53) is no longer write enabled at the addressed location and the addressed location is changed (incremented) in preparation for the next event (38-39). The counter circuit is also reset to zero in preparation for the next interruption event. The number of counts from a clock unit having a known frequency provides the duration of the interruption event. With the use of a clock unit operated at 100 MHz, interrupt events from 10 nanoseconds to 9.99 microseconds can be identified. Because of the frequency at which the testing is performed, the input impedance of the comparator circuit must be matched to the impedance of the circuit interconnection device</p> |