
3. External Connection
SMC-4DL-PCI, SMC-8DL-PCI
35
Connecting Input Signals
Encoder input circuit
Encoder input circuit on this product is illustrated below. The signal input is a differential input capable
of connecting a line driver output, TTL level output and open-collector output.
Connection with the differential output
Board
Driver Unit
A+
A-
AM26LS31 or
equivalence to it
Phase A+
Phase A-
Vcc
B+
B-
AM26LS31 or
equivalence to it
Phase B+
Phase B-
Vcc
Z+
Z-
AM26LS31 or
equivalence to it
Phase Z+
Phase Z-
Vcc
Vcc
Vcc
Vcc
GND
GND
Figure 3.10. Encoder input circuit