Following SMT and PTH assembly, all the boards undergo automated optical inspection in order to prevent and identify any assembly or soldering defects. This test is carried out using a state-of-the-art Omron RNS-pt. Our inspection system guarantees the utmost reliability in all the boards assembled. Thanks to techniques for acquiring special images and processing them using a very special wide-spectrum lighting system, we obtain practically complete coverage of soldering joint and component positioning defects. The operating principle is based on the acquisition of images detected by a high definition camera, combined with a ring lighting system which emits a flash sequence with different wavelengths. The images are then compared with those stored in the library, and if this comparison highlights any possible defects a specialist operator analyzes the signal, and if necessary remedies or flags up the problem. One hundred per cent of our production undergoes this test.
Performing parametric testing is extremely important on both pre-series and high volume, low-cost production in which a high level of accuracy is required by new technology. All this is made possible by our impressive fleet of Spea machinery. In-circuit testing makes it possible to check each single board component from the outset. An ICT is used mainly to intercept errors introduced during production, such as missing or incorrect value components, short or open circuits, inverted polarities and so on. Net contact mechanics (bed of nails or fixture) and circuit analysis software are part of the testing program, using specific equipment for each board composed of contact mechanics and the test program. In the case of a Flying Probe machine, contact mechanics is avoided as the machine positions itself on the points to check by moving its own measurement probes. This technology makes it possible to perform parametric testing on small series productions and sampling as well. With the latest generation Flying Probe and two ICTs we are able to carry out any parametric testing automatically in-house in conditions of maximum security. The test programs are developed by our own highly specialized engineers trained by the world leader in this type of test.
The degree of coverage provided by a test system is always relative, and depends on the type of board and its application. Optical and parametric testing are rarely able to provide total coverage, which is why dedicated functional testing is sometimes necessary. Functional testing is the only way of substantiating and certifying the operation of complex electronic systems, and it is performed at the end of the production line, before the device is released onto the market. By its very nature, functional testing is designed to check devices by carrying out a series of simulations that reproduce the system’s operating conditions and the environmental conditions in which it operates in as realistic a way as possible. Our functional testing solutions (ATE) are general purpose, as they are capable of testing different types of board and electronic device with minimal investment (depending on whether contact fixtures are required or not). These extremely flexible, modular systems can be used to perform low and high frequency signal and power analog and digital measurements, and handle various types of output. In addition we accept the integration of a wide range of external instruments controlled by simple, intuitive software, expanding the potential as required while complying with the features of the specific architecture. A number of our functional test machines are dedicated to specific applications, while any kind of functional test can be carried out on our two general purpose machines.
Automated Optical Inspection -AOI-