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systems with higher data rates or bandwidths that, side. This yields, among other things, extremely low
in turn, must be borne by the interfaces. Through electromagnetic interference (EMI) and extremely
these and other rising demands on the interfaces, fast switching speeds.
such as additional safety in the form of higher LVDS interfaces are often used with control and
dielectric strength, greater reliability, and lower regulating systems in which large data volumes
space requirements, conventional solutions are no must be sent between the electronic circuits or
longer sufficient. Here, too, digital isolators between short cable lengths. They are also used for
represent the best solution because they not only synchronization of different components in a
satisfy the heightened demands for safety, complete application by distributing the clock
performance, and reliability mentioned above but signals very rapidly to the respective components.
also offer integrated isolation and multiple inputs Analog front ends (AFEs) in industrial measurement
and outputs. applications and control systems count among the
typical applications for LVDS. However, they are
High noise immunity also commonly used for realisation of digital
A common method used in signal transmission interfaces between multiple data nodes and in the
applications involves low voltage differential transmission of video signals – for example, via
signaling (LVDS). This involves an established HDMI. Another aspect that should not be neglected
interface standard (TIA/EIA-644) for serial data is the possibility of galvanic isolation that LVDS
transmission, which features a high noise immunity, circuits provide. Hence, they are also used wherever
apart from its extremely energy-saving properties isolation of communication interfaces, such as in
and its high data rate potential of up to a few Gbps. electronic circuits or backplanes, is required.
These positive characteristics can be attributed to Backplanes are circuit boards with multiple
the internally used current control or limitation of connectors for accommodating various add-on
the driver modules to a maximum of 3mA. The board modules. This allows for easy plug and play
signal’s differential voltage is a mere 20mV. extension of the base system to include additional
However, it is subsequently amplified back to the assemblies. However, the add-on modules are often
logic level of 300mV (differential) on the receiver subjected to high voltage transients because, in

July 2020 • INDUSTRIAL TECHNOLOGY EXTRA! • p5