lvds_ch7Chapter 7 Performance testing 7.1 LVDS signal quality Signal quality may be measured by a variety of means. Common methods are: Measuring rise time at the load Measuring jitter in an eye pattern Bit error rate testing Other means Eye patterns and Bit Error Rate Testing (BERT) are commonly used to determine signal quality. These two methods are described next. 7.1.1 LVDS signal quality: jitter measurements using eye patterns This report provides an example of a data rate vs. cable length curve for LVDS drivers and receivers in a typical application for a particular twisted pair cable. The questions of: “How far?” and “How fast?” seem simple to answer at first, but after detailed study, the answers become quite complex. This is not a simple device parameter specification. But rather, a……