VXI and PXI: Competitive or Complimentary? VXI has emerged as a powerful open architecture for automatic test systems in its short thirteen-year history. An evolving new standard for data acquisition and test called PXI has more recently gained a lot of attention. PXI marketers have been promoting PXI as a low cost replacement for VXI. This report examines the key differences between the two architectures and concludes that:VXI and PXI address two different market segments and will co-exist for many years to comeMajor ATE systems are currently best implemented using VXIVXI provides field proven reliability and minimal risk to major ATE customersHigh resolution, low speed data acquisition systems are best implemented using PXISmall, bench top or light weight portable test systems are suited to either architecture; customers should consider future ability to upgrade with existing module technologyHistoryVXI HistoryVXI was designed in 1987 as an open architecture by a consortium of five major instrument manufacturers: HP, Tektronix, Racal, Wavetek and Colorado Data Systems. The USAF was instrumental in kicking off this effort.VXI is based on the VMEbus, with extensions to facilitate high performance multi-vendor automatic test systems. VXI has more than a ten-year track record as a leading architecture for military and commercial automatic test systems.PXI HistoryPXI was designed in 1997 by National Instruments as an architecture for data acquisition instrumentation. PXI stands for Pci eXtensions for Instrumentation. National based PXI on the Compact PCI standard, adding features to address the unique needs of the acquisition and test markets.In August 1997, National Instruments announced Revision 1.0 of the PXI specification. In March 1998 the specification was endorsed by 15 companies, primarily system integrators. In June 1998, the PXI Systems Alliance (PXISA) was formed to discuss and promote the use of PXI as an open standard for da...
