What to do when your automated test equipment and Unit Under Test are out of reach?

Abstract

Cabling from the Unit Under Test (UUT) to the Test System has become an increasingly difficult challenge to overcome. There are a few distinct challenges. The distance between the UUTs and the Test System has become a major challenge with today's high speed busses. Current UUTs and Test Systems have trouble driving long cable lengths of 10 meters or more due to signal integrity reasons, latency, and the skew across high speed busses which can run as fast as 5Gb/s. Also, multipoint busses such as PCI do not have support for external cabling solutions which makes testing difficult. Furthermore, limited space in the General Purpose Interface (GPI) prevents the tester from cabling out all necessary signals. This paper will explore a solution to these problems, which is to bring a piece of the Test System close to the UUT, instead of bringing the UUT close to the Test System. In most Test Systems, there exists a master chassis with instrumentation. The key to solving this problem is to create a small form factor chassis that can be placed close to the UUT, which can be thought of as a Remote Test Head. The Remote Test Head is an extension of the Master Chassis allowing the same instrumentation and software to be used as in the local system; therefore saving the System Designer and TPS Developer from having to design new instrumentation or writing new tests. The connection between the Test System and the Remote Test Head is optical thus alleviating problems with signal integrity. The connection allows the Remote Test Head and the Test System to be more than 10m apart while still maintaining a throughput of 5Gb/s even when going through a GPI.