Method and apparatus for testing electrical connections on a printed circuit board

摘要

A test system and method for identifying open and shorted connections on a printed circuit board (PCB). An integrated circuit (IC) unit on the PCB is configured to generate a test signal on an output pin connected to a test pin on a second device, connector, or socket on the PCB. For a connection, the test signal is capacitively coupled to a detector plate proximal the second device. Based on the signal coupled to the detector, time domain analysis is performed on the coupled signal to determine if the test pin has a good connection to the PCB or if the pin is open or shorted. Analysis may include cross-correlating the coupled signal with a learned signal obtained from a known “good” PCB. The test pin may pass the test if the cross-correlation is within a specified threshold window. If the test fails, additional tests may be performed to troubleshoot the cause of the testing failure.

主权项

1. A method of testing a circuit assembly, the method comprising:
configuring a first component on the circuit assembly to generate a first signal on a first pin of the first component, the first signal comprising at least one leading edge and at least one trailing edge; placing a probe adjacent a second component on the circuit assembly; obtaining a learned signal representative of an expected transient response to the at least one leading edge and at least one trailing edge; performing time domain analysis of a second signal, the second signal being capacitively coupled from the second component to the probe, and the time domain analysis comprising performing a cross-correlation of at least one portion of the second signal to the learned signal, the at least one portion of the second signal comprising a plurality of edges corresponding to the at least one leading edge and the at least one trailing edge; and indicating a test result based on the time domain analysis of the second signal, wherein the test result is a value indicative of a degree of similarity between the at least one portion of the second signal and the learned signal.