quality

ERSASCOPE

A soldered joint has to fulfil an electronic as well as a mechanical function. To guarantee constant and permanent quality, criteria such as quantity of solder and surface integrity have to be considered. The visual inspection by ERSASCOPE combined with x-ray inspection discovers fissures and allows an optimal control of BGA work flows.

Boundary Scan

In order to guarantee the functionality of complex electronic devices, a constant test strategy has to be applied starting with the product development. The Boundary Scan represents, as defined by ANSI / IEEE1149.1, the only standardised test procedure worldwide. Furthermore, it cost-efficiently covers the bigger part of possible tests concerning electronic devices. Compared with traditional test solutions, such as in-circuit emulators (contact via pin), the device-related complexity with Boundary Scan procedures is reduced to a minimum. Furthermore, the Boundary Scan serves to verify certain prototypes. Moreover, we realise changes at short notice throughout the whole manufacturing process by adaptation of the test program.

X-ray

With the application of ball-grid-arrays (BGA) x-ray-inspection became necessary. Every soldering joint, even SMD-pads can be analytically judged. Thereby, we can trace the smallest changes or fluctuations during the manufacturing process with all parameters still being within the normal range. On the basis of this on-line data processing we put up a short control path by which we can anticipate possible manufacturing errors in advance.

Further test procedures for quality assurance:

• optical control
• Burn In
• customised test procedures
• FMEA (failure mode and effect analysis)

Operating Tests and In-Circuit-Tests

Even after the most accurate manufacturing, an electronic device can show an error, e.g. caused by errors on the circuit board, in electronic components or in the manufacturing process itself. Therefore, all devices undergo an operating/system test and/or an in-circuit-test at the customer’s preference. While the in-circuit-test should find all manufacturing errors, the operating test discovers defective or wrong components. The result yields to error rates in the lower “ppm” range (parts per million). Devices for operating tests are either provided by the customer or especially developed by esw ourselves.