Connection to Single Ended Encoder (Incremental/Absolute)

Connection to Single Ended Encoder (Incremental/Absolute)

It is not recommended to connect an encoder single ended because it   creates  strange counting behavior due to signal noise and level drifts.


TTL output uses differential wiring (A with /A and B with /B) to cancel noise.

But... If single ended encoders absolutely MUST be used then try the following:

Bias the complementary input of each channel (A, B and Z) to 2.5V.  This may be simply derived from a pair of 1.5 kOhm resistors in series with one end of the pair connected to 0v and the other end to +5v. The centre point of the pair will form approximately 2.5v.


This does not work well with ALL encoders as the bias resistors require a lot of Power (W) and with some encoders even lower values of resistance will be needed.





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