LT1080, LT1081
ADVANCED LOW-POWER
5-V DUAL EIA-232 DRIVER/RECEIVERS
SLLS050A – D3121, SEPTEMBER 1989 – REVISED FEBRUARY 1991
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Operates With Single 5-V Power Supply
Generates ± 9-V Supply Voltages With Only
1-µF Capacitors
Designed to Avoid Latch-Up
CMOS Comparable Low Power . . . 60 mW
Features Superior to CMOS:
Improved Speed . . . Operates Over
64K Baud
Improved Protection . . . Outputs Can Be
Forced to ± 30 V Without Damage
3-State Outputs Are at High Impedance
When Off
Power Additional EIA-232 Drivers . . . 10 mA
LT1080C, LT1080I . . . DW OR N PACKAGE
(TOP VIEW)
NC
C1 +
VS +
C1 –
C2 +
C2 –
VS –
T2OUT
R2IN
1
18
2
17
3
16
4
15
5
14
6
13
7
12
8
11
9
10
ON/OFF
VCC
GND
T1OUT
R1IN
R1OUT
T1IN
T2IN
R2OUT
NC – No internal connection
LT1081C, LT1081I . . . DW OR N PACKAGE
(TOP VIEW)
1-µA Supply Current in Shutdown
Available With or Without Shutdown
Suitable for ANSI/EIA-232-D-1986
Applications (Revision of EIA Std
RS-232-C)
Designed to Be Interchangeable With
Linear Technology LT1080 and LT1081
C1 +
VS +
C1 –
C2 +
C2 –
VS –
T2OUT
R2IN
1
16
2
15
3
14
4
13
5
12
6
11
7
10
8
9
VCC
GND
T1OUT
R1IN
R1OUT
T1IN
T2IN
R2OUT
description
The LT1080 and LT1081 are dual driver/receivers that include a charge pump to supply EIA-232 voltage levels
from a single 5-V supply. These interface-optimized devices are designed to avoid latch-up and provide a
realistic balance between CMOS levels of power dissipation and real-world requirements for ruggedness. The
driver outputs are fully protected against overload and can be shorted to ± 30 V. Unlike CMOS devices, the
advanced architecture of the LT1080 and LT1081 does not load the signal line when shut down or when the
power is off. Both the receiver and EIA-232 outputs are put into a high-impedance state. An advanced output
stage allows driving higher capacitive loads at higher speeds with exceptional resistance to ESD.
Applications for these devices include portable computers, battery-powered EIA-232 systems, power-supply
generators, terminals, and modems.
The LT1080C and LT1081C are characterized for operation from 0°C to 70°C. The LT1080I and LT1081I are
characterized for operation from – 40°C to 85°C.
Copyright © 1991, Texas Instruments Incorporated
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
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