Compax3 Hardware - Single Ended Step & Direction (I10T10)

Single-Ended Input for Compax3

If the customer cannot provide a differential RS422 signal because he has only a single-ended open-collector signal then he has to use an external 332 ohm open-collector resistor for the RS422 input, the inverse RS422 input needs a voltage-divider circuit with 821ohm / 600ohm and a 100nF capacitor. 

Duplicate the circuit below for Step and Direction.

Open

Single-Ended Step & Direction Diagram

The RS422 inputs have bus termination, and we use that capacitor to have a constant potential on the Step- and Direction- signals. 

Step

Direction