PC based, IEEE signal & test description standard, synthetic instruments

There exists a trend in automatic test environments (ATE) towards the synthesis of signals using digital memory devices, which, through recent advances in technology, are now able to achieve output at frequencies that were previously the domain of analogue devices. This paper discusses the use of a recent trend in PC technology, DirectX/sup /spl reg//, to enable real-time streaming of test signal definitions directly to digital memory devices, onboard a standard PC that is also running the automated test program (ATP). We consider the use of the emerging IEEE signal & test description (STD) standard to allow us to define stimulus signals using the STD basic signal components (e.g. sinusoid, AM, clock). We have devised a system that enables us to design, simulate and implement complex stimulus signals and measurements at useful frequencies, on a single machine. We have used STD to ensure an international standard, providing flexibility, portability and a natural source for simulation. By mapping STD signal modelling language (SML) onto a DirectX/sup /spl reg// framework, we have created a real-time simulation and, through onboard PC hardware, a real-world signal.