IC-HF Datasheet, PDF (10/36 Pages) IC-Haus GmbH – 6-CH. ENCODER LINK, RS-422 DRIVER/RECEIVER

iC-HF
preliminary
6-CH. ENCODER LINK, RS-422 DRIVER/RECEIVER
RS422 Output
Qi
Xi
TRI
NQi
Rev C1, Page 10/36
RS422 Input
Qi
Xi
+
_
TRI
NQi
Figure 5: Equivalent circuit of RS-422 transmitter
Figure 6: Equivalent circuit of RS-422 receiver
If the channel is a receiver, differential input signals at
pins Qi/NQi are converted into single ended signals at
Xi outputs. Incoming differential signals should follow
RS-422 protocol. External resistors may be required to
adapt signal voltage levels to iC-HF internal voltages.
More information on the RS-422 receiver on page 22.
If the channel is in Encoder Link State, signals present
at input pins Xi are bypassed and directly connected to
output pins Qi. Bidirectional channels in Encoder Link
State present one bypassed line. Pull-up resistors and
the output drivers are disabled. No signal is connected
to NQi pins.
Output Enable bit OEN must be set hi in order enable
Xi
the single ended output driver. With OEN = 0, the driver
is left in high impedance.
Encoder Link
Qi
NQi
In RS-422 receiver configuration the pull-down resistor
is disabled and the differential output driver is left in
high impedance.
Figure 7: Equivalent circuit of one line in Encoder
Link State