Automated Test System for STOS DVA device

Automated test system for STOS device
Developed for in-house testing purposes.

STOS DVA is a thin Ethernet display client based on 600 MHz Texas Instruments’ multimedia DSP. The device features three video outputs and three inputs for human interface devices e.g. small keyboards. The whole product design cycle was done by IMPT under a custom development project, including design for manufacturing, automated test development and production. The device was designed to be highly reliable and robust in order to meet 24/7 operation requirements. Therefore, it was crucial to perform thorough testing.

The automated test system which was designed for the STOS DVA testing performs the following test procedures:

•    Short/open circuit test
•    Voltage test
•    PLL programming
•    Frequency measuring
•    Reset circuit test
•    Microcontroller test and programming
•    Main processor test
•    Video DAC test
•    SDRAM memory test
•    MAC setting and firmware download with Flash check

The test system is based on National Instruments’ PXI platform with virtual instrumentation cards. The software for the automated test was designed in LabVIEW development environment. A custom bed of nails was developed as an interface between device under test (DUT) and virtual instrumentation cards. Over 1600 devices were tested and delivered up to date, with an average testing time of four minutes per device. The operator involvement was minimized during the test operation and the test results database enabled easy tracking and solving of all kinds of problems that appeared in the production process. During the production process, we managed to bring down the failure rate below 1%. At the end, only 6 devices out of 1000 weren’t delivered due to malfunction. We are very proud by the fact that out of the first 1000 pieces batch, after one year of operation, the customer returned only one device because of hardware failure.