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66 SMT Magazine • May 2014 In-circuit Test automation Challenges The slow adoption of ICT systems into the main automated assembly line is due to the fact that they have unique characteristics that make them much more challenging to automate than imaging systems. Equipment Size ICT systems typically contain a large variety of test modules that are utilized to electrically test the product under test. These modules in- clude test controllers, system & user power sup- plies, AC & DC voltage source/measurement units, waveform generators, digitizers, timer/ counters, and high-speed digital driver and sen- sor pins. These instruments gain access to the product being tested through a complex swit- ching matrix and test receiver that typically re- quires thousands of relays and test probes. The physical dimensions of ICT systems are driven primarily by the required amount of test instruments and the maximum tester pin ca- pacity, which have typically made them much larger than imaging systems. Many ICT systems are designed with a support infrastructure that can support thousands of test pins allowing them to be used for a wide variety of product ap- plications. This makes the equipment size quite large, even for manufacturers of small products that only require low pincount tester configu- rations. Automating these large general purpo- se electrical test systems have traditionally re- quired large adaptation efforts, complex setup, bulky handling equipment, additional support bays and a large amount of factory floorspace. Figure 2 shows an example of an ICT so- lution where the test instrumentation is inte- grated directly into the automation equipment. This implementation requires additional sup- port bays to hold all the instrumentation which increases floor space and the length of the man- ufacturing line. Most manufacturers prefer their Figure 1: overlapping and complementary fault detection properties of test & inspection equipment. THE CHaNGING ECoNomICS oF IN-CIRCUIT TEST continues feATuRe