TTL / 5V
DB25 Male Port
Getting Started
1
Model 422TTL converts RS-422 or EIA-530 signals to
5V TTL (“Transistor Transistor Logic”) at data rates up to
115.2 kbps. Two channels are used to convert RS-422 to
TTL. Two channels are used to convert TTL to RS-422.
Product Overview
RS-422 / EIA-530
DB25 Female Port
Pinouts
2
Pin 7 is signal ground for both connectors (see diagram
below).
Open pads are provided for each line. If desired, you can
change the pin connectors for any of the 4 channels.
When converting a second RS-422 channel, use the
corresponding RTS “A” and RTS “B” pins (see diagram below).
422TTL Schematic Diagram
422TTL SPECIFICATIONS
Baud Rate
Up to 115.2 kbps
RS-422/
EIA-530
Signals
TDA(-), TDB(+), RDA (-), RDB (+),
RTS A(-), RTS B(+), CTS A(-), CTS B(+)
TTL Signals
TD, RD, RTS, CTS
Power
Requires 12 VDC external power supply
MTBF
1539882 hours
Model 422TTL inverts the TTL signal. To determine
polarity, refer to the table below .
Model 422TTL - Polarity (Volts)
RS-422 / EIA-530 Output
TTL Input
V(A) - V(B)
High
Negative
Low
Positive
TTL Output
V(A) - V(B)
RS-422 / EIA-530 Input
High
Negative
Low
Positive
Polarity
3
Power
Jack