The digital encoder interface (Ch1 … Ch6) supports single-ended TTL
and differential RS422 signals with the following characteristics.
Electrical characteristics
Parameter Value
RS422 differential
mode
RS422 input
voltage
High
Low
Diff > +0.2 V
Diff < –0.2 V
n Diff = Voltage difference between
inverted and non-inverted signal
n The inverted and non-inverted signal
must be in the range 0 … 5 V.
Input impedance The input impedance gradually drops from
14 kΩ at DC to 210 Ω at the corner
frequency of 225 kHz.
TTL single‑ended
mode
Min. Max.
TTL input voltage High
Low
2.0 V
0 V
5.0 V
0.8 V
Input impedance Approx. 14 kΩ
Power-up default The behavior of inputs is not critical for
connected devices.
Analog Encoder Interface: I/O Circuit and Electrical
Characteristics
The analog encoder interface (Ch7) supports 1 V
pp
or 11 μA
pp
differential signals (programmable by software).
Objective
s
Incremental Encoder Interface
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