LT1039/LT1039-16
RS232 Driver/Receiver
with Shutdown
FEATURES
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DESCRIPTIO
Operates from
±5V
to
±15V
Supplies
Fully Protected Against Overload
Outputs Can Be Driven
±30V
Without Damage
Three-State Outputs; Outputs Open When Off
Bipolar Circuit—No Latchup
±30V
Input Range
Triple Driver/Receiver
No Supply Current in Shutdown
30kΩ Input Impedance
Meets All RS232 Specifications
16-Pin Version—Pin Compatible with MC145406
Available in SO Package
15kV ESD: LT1039A
The LT
®
1039 is a triple RS232 driver/receiver that in-
cludes shutdown. Each receiver will accept up to
±30V
input and can drive either TTL or CMOS logic. The RS232
drivers accept TTL logic inputs and output RS232 voltage
levels. The outputs are fully protected against overload
and can be shorted to ground or up to
±30V
without
damage to the drivers. Additionally, when the system is
shut down or power is off, the outputs are in a high
impedance state allowing data line sharing. Bipolar cir-
cuitry makes this driver/receiver exceptionally rugged
against overloads and immune to latchup.
A BIAS pin allows one receiver to be kept on while the rest
of the part is shut down.
The LT1039 is also available in the 16-pin version,
without shutdown or BIAS pin functions.
For applications requiring operation from a single 5V
supply, see the LT1080/LT1081, LT1180A/LT1181A and
LT1130A data sheets. For applications requiring 15kV
ESD, see the LT1039A.
, LTC and LT are registered trademarks of Linear Technology Corporation.
APPLICATIO S
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RS232 Interface
Terminals
Modems
TYPICAL APPLICATIO
12V
BIAS*
RS232 IN
1
2
3
V
+
LT1039
V
CC
18
17
16
5V
ON/OFF
LOGIC
V
+
POSITIVE
– 0.5
OUTPUT VOLTAGE (V)
30k
RS232 OUT
RS232 IN
4
5
30k
RS232 OUT
RS232 IN
6
7
30k
*BIAS PIN USED
RS232 OUT
TO KEEP THE
RECEIVER ON
– 12V
WHILE IN SHUTDOWN
8
9
V
–
15
14
LOGIC
LOGIC
1.5
NEGATIVE
1.0
13
12
LOGIC
LOGIC
0.5
11
GND
1039 TA01
LOGIC
V
–
0
2
10
U
Driver Output Swing
6
8
4
OUTPUT CURRENT (mA)
10
1039 TA02
U
U
1039fd
1