A Brief History of Automated Test

Products vary in their complexity, as does right test solution for that application. Often, the more complex the product, the more expensive it will be to manufacture and test.

Automated test equipment is used throughout the product development lifecycle from initial prototype development, through first batch testing and finally into full production. The same test systems are then quite often used in repair stations or at the site of contract manufacturers (CMs). With the recent trends to outsource manufacturing to offshore locations in the Far East and Eastern Europe, a great deal of the new test equipment purchased is now found in these areas.

The test equipment used in these facilities, however, is generally designed and developed in a US or Western European headquarters near the companies’ R&D center. This is to enable engineers to share initial ideas about how best to test a product and come up with a cost-effective solution for testing it. Once the development and testing of the test equipment has taken place, the equipment is shipped to offshore manufacturing facilities or CMs to be installed and commissioned. It is often the case that the test development engineers install the equipment and train the local operators on how to use the equipment to obtain maximum performance.

The decision on what test equipment to use is generally determined by the type of product being manufactured. Historically, automated test equipment (ATE) was expensive and difficult to program and was primarily used on mission-critical products. 

The early test equipment was affectionately known as “Rack and Stack,” and, as the name suggests, it was a rack-based test system stacked full of individual instruments. These were often connected together with General Purpose Interface Bus (GPIB), invented in the 1960s by Hewlett-Packard. GPIB is an 8-bit parallel bus that had the advantage of enabling the software developer to address each individual piece of instrumentation through a unique and intuitive addressing system. As such, a software developer could decide which instruments to control, in what order, and when to return the test results. GPIB created a revolution in test system design and is still in widespread use today.

Test equipment has evolved in leaps and bounds over the past two decades with faster buses such as PCI, PCI Express, PXI, Ethernet, USB, and many more. These new standards enable much faster transfer of data between the test equipment instrumentation and the computer. As a result, automated test equipment has reduced in cost and increased in performance significantly. Currently, fully functional ATE can cost as little as a few thousands of dollars compared to hundreds of thousands in the 1980s and earlier.

With the falling prices, there has been a proliferation in ATE adoption by companies everywhere. Once the domain of testing only mission-critical products, ATE systems are now commonplace in most electronic manufacturing companies, producing a range of products from low cost to high value.