5
MIL-188 SPECIFICATIONS
Voltage levels
MIL-188-C single ended input uses positive true logic. The normally idle, or marking, line is
represented as +5 volts output. The start bit, or space condition, causes the output to switch
to -5 volts.
MIL-188-114 differential transmission utilizes two wires per signal. Signal voltage is at +5,
while the other signal voltage is at -5 volts.
LINE TERM INATION
Each receiver is terminated in a 180 ohm resistor. The drivers have 10 ohm current limiting
resistors in series with the output signal for protection.
SIGNAL
NAME
PIN #
MODE
GND
Ground
7
RDB
RX+
Receive Positive
16
Input
RDA
RX-
Receive Negative
3
Input
CTSB
CTS+
Clear To Send Pos.
13
Input
CTSA
CTS-
Clear To Send Neg.
5
Input
DSRB
DSR+
Data Set Ready Pos.
22
Input
DSRA
DSR
Data Set Ready Neg.
6
Input
DCDB
DCD+
Data Carr. Detect Pos.
10
Input
DCDA
DCD-
Data Carr. Detect Neg.
8
Input
TDB
TX+
Transmit Positive
14
Output
TDA
TX-
Transmit Negative
2
Output
RTSB
RTS+
Req. To Send Pos.
19
Output
RTSA
RTS-
Req. To Send Neg.
4
Output
DTRB
DTR+
Data Term. Ready Pos.
23
Output
DTRA
DTR-
Data Term. Ready Neg.
20
Output
FIGURE 5
MIL-188-114 PIN-OUT
SIGNAL
NAME
PIN #
MODE
GND
Ground
7
RDB
RX+
Receive Positive
16
Input
CTSB
CTS+
Clear To Send Pos.
13
Input
DSRB
DSR+
Data Set Ready Pos.
22
Input
DCDB
DCD+
Data Carr. Detect Pos.
10
Input
TDB
TX+
Transmit Positive
14
Output
RTSB
RTS+
Req. To Send Pos.
19
Output
DTRB
DTR+
Data Term. Ready Pos.
23
Output
FIGURE 6
MIL-188-C PIN-OUT
