Black Box IC470A - Appendix C: Block Diagrams; IC470 A through IC472 A Models

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RS-232↔RS-422 INTERFACE CONVERTERS
Appendix C: Block Diagrams
C.1 IC470A through IC472A Models
DCE
DATA
DTE
TD
2
RD
3
RD
3
TD
2
OUTPUT
BUFFER
OUTPUT
BUFFER
TRANSMITTED DATA
CLAMPED TO 3v p-p
XMT +
XMT -
DCE
DTE
SCHMITT
TRIGGER
ACTIVE
FILTER
RCV +
RCV -
GND
SG
FG
7
1
POWER
SUPPLY
+V
-V
DATA
RTS
4
CTS
5
DSR
6
CD
8
20
DTR
NOTE: The directions of signal flow shown here are for a unit set to DCE.
NOTE: The RCV+ line is held negative with respect to RCV– when no data is being received.