LT1039A-16_15 Datasheet, PDF (5/14 Pages) Linear Technology – Triple RS232 Driver/Receiver with Shutdown

LT1039A/LT1039A-16
Typical Performance Characteristics
Shutdown to Driver Output
Shutdown to Receiver Output
BIAS Pin Response Time
10V
RECEIVER
OUTPUT
5V
0V
0V
DRIVER
OUTPUT ^–5V
–10V
ON/OFF
INPUT
5V
0V
V⁺ = 12V
V^– = –12V
R_L = 3k
2µs/DIV
OUTPUT
HIGH
OUTPUT
LOW
6V
RECEIVER ^4V
OUTPUT _2V
0V
ON/OFF ^5V
INPUT _0V
1039A G10
V_CC = 5V
2ms/DIV
6V
RECEIVER 1
OUTPUT
4V
2V
0V
BIAS INPUT
(THRU 25kΩ)
5V
0V
1039A G11
V_CC = 5V
0.2µs/DIV
1039A G12
Pin Functions (Pin numbers listed are for 18-pin device)
V⁺, V^– (Pins 1, 9): Driver Supply Pins. Supply current
drops to zero in shutdown mode. Driver outputs are in a
high impedance state when V⁺ and V^– = 0V.
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.
output pins are internally protected from ESD transients.
In order to insure proper functioning of the ESD protec-
tion devices, the V⁺ and V^– supply pins must be bypassed
with low ESR capacitors located close to thepins. 0.1µF
ceramic capacitors work well.
GND (Pin 10): Ground Pin.
REC IN (Pins 3, 5, 7): Receiver Input Pins. Accepts
RS232 voltage levels (±30V) and has 0.4V of hysteresis
to provide noise immunity. Input impedance is nominally
30kΩ. Receiver input pins are internally protected from
ESD transients. In order to insure proper functioning of
the ESD protection devices, the V_CC and V^– supply pins
must be bypassed with low ESR capacitors located close
to the pins. A 0.1µF 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
shutdown mode or when power is off (V⁺ and V^– = 0V)
to allow data line sharing. Outputs are fully short-circuit
protected from V^– + 30V to V⁺ – 30V with power on, off
or 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-
TR IN (Pins 11, 13, 15): RS232 Driver Input Pins. Inputs
are TTL/CMOS compatible. Inputs should not be allowed
to float. Tie unused inputs to V_CC.
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 shar-
ing. Outputs are fully short-circuit protected to ground or
V_CC with power on, off or in the shutdown mode.
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.
V_CC (Pin 18): 5V Power for Receivers.
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