TE S T & ME ASUREMENT HANDBOOK
Testing LVDS devices at the margins with an AWG Advanced arbitrary waveform generators have simplified the testing associated with communications over low-voltage differential signaling lines.
First introduced in 1994, low-voltage differential signaling (LVDS) has gone on to become widely used in products such as LCD panels, automotive infotainment systems, industrial cameras and machine vision, notebook and tablet computers, communications systems, and more. Unlike other 90s-era standards that have come and gone, LVDS continues to thrive in its traditional applications as well as in newer applications that require high-data-rate transmissions including automotive radar and lidar, industrial, Internet of Things (IoT), and high-energy physics applications.
CHRIS LOBERG |
TEKTRONIX
The need for robust signal margin performance rises as a generalpurpose interface like LVDS is applied in these more demanding settings. This testing requires robust signal generation to test and stress LVDS receivers from R&D through to production. In the past, these signals were generated in number of ways, ranging from use of a data-pattern generator to development of custom FPGAs. Those methods have become outdated with the introduction of arbitrary waveform generators (AWG) which have the channel counts and data rates needed to thoroughly test LVDS protocol and receiver margins. LVDS applications often require a large number of outputs, with over five differential pairs being the norm.
Typical LVDS setup Coupled fields
Driver Current source
3.5 mA
Fringing fields 350 mV 100Ω
Cross section of differential pair
Receiver
LVDS is a differential signaling system defined under ANSI/TIA/EIA-644.
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