5

LT1039A/LT1039A-16

Shutdown to Receiver Output

BIAS Pin Response Time

drops to zero in shutdown mode. Driver outputs are in a

BIAS (Pin 2): Keeps receiver 1 on while the LT1309A is in

the shutdown mode. Leave BIAS pin open when not in use.

See Applications Information for proper use.

REC IN (Pins 3, 5, 7): Receiver Input Pins. Accepts RS232

voltage levels (

±30V) and has 0.4V of hysteresis to pro-

vide noise immunity. Input impedance is nominally 30k

Ω.

Receiver input pins are internally protected from ESD

transients. In order to insure proper functioning of the ESD

bypassed with low ESR capacitors located close to the

pins. A 0.1

µF ceramic capacitor works well.

TR OUT (Pins 4, 6, 8): Driver Outputs with RS232 Voltage

Levels. Outputs are in a high impedance state when in the

allow data line sharing. Outputs are fully short-circuit

in the shutdown mode. Typical output breakdowns are

greater than

±45V and higher applied voltages will not

damage the device if moderately current limited. Driver

output pins are internally protected from ESD transients.

In order to insure proper functioning of the ESD protec-

bypassed with low ESR capacitors located close to the

pins. 0.1

µF ceramic capacitors work well.

GND (Pin 10): Ground Pin.

TR IN (Pins 11, 13, 15): RS232 Driver Input Pins. Inputs

are TTL/CMOS compatible. Inputs should not be allowed

REC OUT (Pins 12, 14, 16): Receiver Outputs with TTL/

CMOS Voltage Levels. Outputs are in a high impedance

state when in the shutdown mode to allow data line

sharing. Outputs are fully short-circuit protected to ground

ON/OFF (Pin 17): Controls the operation mode of the

LT1039A and is TTL/CMOS compatible. A logic low puts

the device in the shutdown mode which reduces input

supply current to zero and places both driver and receiver

outputs in a high impedance state.

6V

4V

2V

0V

RECEIVER

OUTPUT

5V

0V

ON/OFF

INPUT

2ms/DIV

1039A G11

5V

BIAS INPUT

(THRU 25k

Ω)

0.2

µs/DIV

1039A G12

0V

2V

4V

6V

RECEIVER 1

OUTPUT

0V