Make sure you’re testing the Production Process, not the Design Process

Production Testing is a quite different methodology to Design Testing, however they often get confused. The result of this is a production test system that verifies the products design rather that the processes used to assemble it.

What is the difference between these two types of test?

Design Testing: - The aim of this testing is to ensure that the product design meets the requirements specification. For example these requirements could include items such as functionality, useability, electromagnetic radiation and conducted emission standards. Design testing is often tightly linked to the development cycle and is usually repeated on a periodic basis as new features or refinements are made. It is a comprehensive test of the product against the requirements specification.

Production Testing: - The aim of this testing is the verification of the production process through electrical and mechanical tests. For example a port connector is placed on the board under test and needs to be verified. One method identified to exercise the port may be to use a feature of products functionality to transmit data through the port. Another method may be to plug in a connector and perform a continuity test on each pin. Production testing is ideally fast and is performed many times a day.

By working with the development team, the production test team can determine the best methods to test the product from the production point of view. Some tests may require additional functionality to be added to the product (such as a ‘production test’ mode that allows outputs to be exercised) and so it is advisable to involve the production test team early on in the development process.

Peter Brown
Managing Director
Nightside Test Design Ltd.
www.nightside.co.nz