LT1039AISW Linear Technology, LT1039AISW Datasheet - Page 6

• Manufacturer Part Number: LT1039AISW
• Description: Triple RS232 Driver/Receiver with Shutdown
• Manufacturer: Linear Technology

APPLICATIONS
LT1039A/LT1039A-16
The driver output stage of the LT1039A offers signifi-
cantly improved protection over older bipolar and CMOS
designs. In addition to current limiting, the driver output
can be externally forced to 30V with no damage or
excessive current flow.
The driver outputs utilize high impedance overvoltage
protection, eliminating the flow of fault currents into
supplies, as will happen with conventional diode clamp
configurations.
6
Placing the LT1039A in the shutdown mode (Pin 17 low)
puts both the driver and receiver outputs in a high imped-
ance state. This allows data line sharing and transceiver
applications.
(CHANNEL SELECT)
INPUT A
INPUT B
Older RS232 Drivers and Other CMOS Drivers
ON/OFF
LOGIC
LOGIC
INPUT
LT1039A
Sharing a Transmitter Line
U
LT1039A Driver
LT1039A #1
LT1039A #2
DRIVER
DRIVER
INVERTER
INFORMATION
LOGIC
U
OUTPUT CAN
EXTERNALLY
BE FORCED
V
V
+
–
1039A AI03
W
WITH SOME DRIVERS,
EXTERNALLY APPLIED
VOLTAGE CAN FORCE
THE SUPPLIES
1039A AI01
RS232
TRANSMISSION
LINE
1039A AI02
U
30V
– 30V
The shutdown mode also drops all supply currents (V
V
(TRANSMIT/RECEIVE)
TRANSMIT/RECEIVE
+
, V
(CHANNEL SELECT)
–
) to zero for power conscious systems.
ON/OFF
LOGIC
INPUT
INPUT A
INPUT B
ON/OFF
LINE
RS232
RS232
INPUT
Sharing a Receiver Line
LT1039A #1
DRIVER
Transceiver
INVERTER
LT1039A #1
LT1039A #2
LT1039A #2
RECEIVER
LOGIC
RECEIVER
RECEIVER
INVERTER
LOGIC
1039A AI05
1039A AI04
RS232
TRANSMIT/RECEIVE
LINE
LOGIC
OUTPUT
CC
,