The hi-speed USB 2.0 serial bus is used today in a broad range of computer as well as embedded designs. One good example of an embedded design is the oscilloscope itself, which often includes USB interfaces for connectivity, mouse operation, and external data storage. Most other types of electronic products, such as medical equipment or industrial control systems, include USB interfaces as well. The USB 2.0 serial interface has been rapidly replacing older RS-232 serial interfaces in embedded designs.
Although USB-IF physical layer compliance certification is typically required by computer OEMs for suppliers of USB devices and silicon chip-sets, compliance certification is typically not a requirement for embedded products. Nonetheless, R&D testing and verification of physical layer characteristics of embedded designs with integrated USB interfaces is extremely important to ensure reliable operation of end-products. Simply selecting USB components, integrating them into an embedded design, and then hope that everything functions is not good enough. Even if the system appears to function, how much margin does it have? Or how does it perform under various environmental conditions such as temperature or humidity?
