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LT1039/LT1039-16

1039fd

The driver output stage of the LT1039 offers significantly

improved protection over older bipolar and CMOS de-

signs. In addition to current limiting, the driver output

can be externally forced to

±30V with no damage or

excessive current flow, and will not disrupt the supplies.

LT1039 Driver

Some drivers have diodes connected between the out-

puts and the supplies, so externally applied voltages can

cause excessive supply voltage to develop

LT1039 #1

DRIVER

LT1039 #2

DRIVER

LOGIC

INPUT A

LOGIC

INPUT B

1039 AI03

ON/OFF

(CHANNEL SELECT)

INPUT

LOGIC

INVERTER

RS232

TRANSMISSION

LINE

Sharing a Receiver Line

WITH SOME DRIVERS,

EXTERNALLY APPLIED

VOLTAGE CAN FORCE

THE SUPPLIES

1039 AI02

Older RS232 Drivers and Other CMOS Drivers

Sharing a Transmitter Line

Placing the LT1039 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.

–30V

30V

OUTPUT CAN

BE FORCED

EXTERNALLY

1039 AI01

LT1039

Transceiver

LT1039 #1

RECEIVER

RS232

INPUT A

RS232

INPUT B

1039 AI04

ON/OFF

(CHANNEL SELECT)

INPUT

LOGIC

INVERTER

LOGIC

OUTPUT

LT1039 #2

RECEIVER

LT1039 #1

DRIVER

LOGIC

TRANSMIT/RECEIVE

LINE

RS232

TRANSMIT/RECEIVE

LINE

1039 AI05

ON/OFF

(TRANSMIT/RECEIVE)

INPUT

LOGIC

INVERTER

LT1039 #2

RECEIVER