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TR-Electronic GmbH 2016, All Rights Reserved
10/31/2018
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4.3 SSI – interface (optional)
4.3.1 RS422 Data transmission technology
With the RS422 transmission one line-pair is used for the signals Data+ and Data–
and one line-pair for the signals Clock+ and Clock–.
The serial data are transmitted without mass reference as a voltage difference
between two corresponding lines.
The receiver evaluates only the difference between the two lines. Therefore common-
mode interferences on the transmission line do not lead to a corruption of the useful
signal.
By the use of shielded and twisted pair cable, data transmissions over distances from
up to 500 meters with a frequency of 100 kHz can be realized.
Under load RS422 transmitters provide output levels of ±2V between the two outputs.
RS422 receivers still recognize levels of ±200mV as valid signal.
