1
LT1080/LT1081
10801fe
Advanced Low Power
5V RS232 Dual Driver/Receiver
The LT
®
1080/LT1081 are the only dual RS232 driver/
receiver with charge pump to guarantee absolutely no
latchup. These interface optimized devices provide a real-
istic 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 ±30V. Unlike CMOS, the advanced architecture
of the LT1080/LT1081 does not load the signal line when
“shut down” or when power is off. Both the receiver and
RS232 outputs are put into a high impedance state. An
advanced output stage allows driving higher capacitive
loads at higher speeds with exceptional ruggedness
against ESD.
For applications requiring up to five drivers and five
receivers with charge pump in one package see the LT1130A
Series data sheet. A version of the LT1080/LT1081, the
LT1180A and LT1181A that use only 0.1µF capacitors, is
also available. All of Linear Technology’s RS232 ICs are
available in standard surface mount packages.
■
Superior to CMOS
– Improved Speed: Operates over 120kBaud
– Improved Protection: Outputs Can Be Forced
to ±30V without Damage
– Three-State Outputs Are High
Impedance When Off
– Only Needs 1µF Capacitors
■
Absolutely No Latchup
■
CMOS Comparable Low Power: 60mW
■
Can Power Additional RS232 Drivers: 10mA
■
Supply Current in Shutdown: 1µA
■
Available in SO Package
■
Available with or without Shutdown
, LTC and LT are registered trademarks of Linear Technology Corporation.
■
Portable Computers
■
Battery-Powered RS232 Systems
■
Power Supply Generator
■
Terminals
■
Modems
Supply Generator Outputs
OUTPUT CURRENT (mA)
02468101214161820
OUTPUT VOLTAGE (V)
1080/81 TA01a
10
8
6
4
2
0
–2
–4
–6
–8
–10
V
CC
= 5V
V
+
OUTPUT
R
L
TO V
–
R
L
TO GND
R
L
TO GND
R
L
TO V
+
V
–
OUTPUT
LOGIC
INPUTS
LOGIC
OUTPUTS
ON/OFF 18
10
13
11
12
6
5
4
2
16
9
14
8
15
7
3
17 5V INPUT
9V OUTPUT
–9V OUTPUT
RS232 OUTPUT
RS232 OUTPUT
RS232 INPUT
RS232 INPUT
1080/81 • TA01
5k
5k
LT1080
1µF
1µF
1µF
1µF
FEATURES
DESCRIPTIO
U
APPLICATIO S
U
TYPICAL APPLICATIO
U
2
LT1080/LT1081
10801fe
A
U
G
W
A
W
U
W
ARBSOLUTEXI T
IS
Supply Voltage (V
CC
) ................................................. 6V
V
+...........................................................................................
12V
V
–.......................................................................................
–12V
Input Voltage
Driver ........................................................... V
–
to V
+
Receiver ................................................. –30V to 30V
ON/OFF Pin .............................................. GND to 12V
Output Voltage
Driver ................................. (V
–
+ 30V) to (V
+
– 30V)
Receiver .................................. –0.3V to (V
CC
+ 0.3V)
Short-Circuit Duration
V
+......................................................................................
30 sec
V
–......................................................................................
30 sec
Driver Output ............................................... Indefinite
Receiver Output ........................................... Indefinite
Operating Temperature Range
LT1080C/LT1081C ................................. 0°C to 70°C
LT1080I/LT1081I................................ –40°C to 85°C
LT1080M/LT1081M (OBSOLETE) ... –55°C to 125°C
Storage Temperature Range ..................–65°C to 150°C
Lead Temperature (Soldering, 10 sec)................. 300°C
LT1081CN
LT1081CSW
LT1081IN
LT1081ISW
LT1081CJ
LT1081MJ
LT1080CN
LT1080CSW
LT1080IN
LT1080ISW
LT1080CJ
LT1080MJ
ORDER PART
NUMBER
ORDER PART
NUMBER
TJMAX = 150°C, θJA = 120°C/W, θJC = 50°C/W (N)
TJMAX = 150°C, θJA = 90°C/W, θJC = 26°C/W (SW)
WU
U
PACKAGE/ORDER I FOR ATIO
TJMAX = 150°C, θJA = 120°C/W, θJC = 50°C/W (N)
TJMAX = 150°C, θJA = 95°C/W, θJC = 27°C/W (SW)
1
2
3
4
5
6
7
8
TOP VIEW
16
15
14
13
12
11
10
9
C1
+
V
+
C1
–
C2
+
C2
–
V
–
TR2 OUT
REC2 IN
V
CC
GND
TR1 OUT
REC1 IN
REC1 OUT
TR1 IN
TR2 IN
REC2 OUT
N PACKAGE
16-LEAD PDIP
SW PACKAGE
16-LEAD PLASTIC SO WIDE
LT1081
SW PACKAGE
18-LEAD PLASTIC SO WIDE
1
2
3
4
5
6
7
8
9
TOP VIEW
N PACKAGE
18-LEAD PDIP
18
17
16
15
14
13
12
11
10
NC
C1
+
V
+
C1
–
C2
+
C2
–
V
–
TR2 OUT
REC2 IN
ON/OFF
V
CC
GND
TR1 OUT
REC1 IN
REC1 OUT
TR1 IN
TR2 IN
REC2 OUT
LT1080
(Note 1)
Consult LTC Marketing for parts specified with wider operating temperature ranges.
J PACKAGE
18-LEAD CERDIP
TJMAX = 150°C, θJA = 100°C/W, θJC = 40°C/W (J)
J PACKAGE
16-LEAD CERDIP
TJMAX = 150°C, θJA = 100°C/W, θJC = 40°C/W (J)
OBSOLETE PACKAGE
Consider N Package for Alternate Source
OBSOLETE PACKAGE
Consider N Package for Alternate Source
3
LT1080/LT1081
10801fe
ELECTRICAL C CHARA TERISTICS
The ● denotes the specifications which apply over the full operating
PARAMETER CONDITIONS MIN TYP MAX UNITS
Driver
Output Voltage Swing Load = 3k to GND Both Outputs Positive ● 5 7.3 V
Negative ●–5 –6.5 V
Logic Input Voltage Level Input Low Level (V
OUT
= High) ●1.4 0.8 V
Input High Level (V
OUT
= Low) ●2 1.4 V
Logic Input Current V
IN
≥ 2V ●520 µA
V
IN
≤ 0.8V ●520 µA
Output Short-Circuit Current Sourcing Current, V
OUT
= 0V 9 12 mA
Sinking Current, V
OUT
= 0V –9 –12 mA
Output Leakage Current SHUTDOWN (Note 3), V
OUT
= ±30V ●10 100 µA
Data Rate (Note 6) R
L
= 3k, C
L
= 2500pF 120 kBd
R
L
= 3k, C
L
= 1000pF 250 kBd
Slew Rate R
L
= 3k, C
L
= 51pF 4 15 30 V/µs
Receiver
Input Voltage Thresholds Input Low Threshold Commercial ●0.8 1.3 V
Industrial and Military ●0.2 1.3 V
Input High Threshold Commercial ●1.7 2.4 V
Industrial and Military ●1.7 3.0 V
Hysteresis ●0.1 0.4 1 V
Input Resistance V
IN
= ±10V 3 5 7 kΩ
Output Voltage Output Low, I
OUT
= –1.6mA ●0.2 0.4 V
Output High, I
OUT
= 160µA (V
CC
= 5V) ●3.5 4.8 V
Output Short-Circuit Current Sinking Current, V
OUT
= V
CC
–10 –20 mA
Sourcing Current, V
OUT
= 0V 0.6 1 mA
Output Leakage Current SHUTDOWN (Note 3), 0V ≤ V
OUT
≤ V
CC
●110 µA
Power Supply Generator (Note 4)
V
+
Output Voltage I
OUT
= 0mA 8.0 9.0 V
I
OUT
= 10mA 7.0 8.0 V
I
OUT
= 15mA 6.5 7.5 V
V
–
Output Voltage I
OUT
= 0mA –7.5 –8.5 V
I
OUT
= –10mA –5.5 –6.5 V
I
OUT
= –15mA –5.0 –6.0 V
Supply Current ●12 22 mA
Supply Leakage Current (V
CC
) SHUTDOWN (Note 3), LT1080 Only ●1 100 µA
ON/OFF Pin Current 0V ≤ V
ON/OFF
≤ 5V, LT1080 Only ●–15 80 µA
Supply Rise Time (Note 5), LT1080 Only 1 ms
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2: These parameters apply for 4.5V ≤ V
CC
≤ 5.5V and V
ON/OFF
= 3V,
unless otherwise specified.
Note 3: V
ON/OFF
= 0.4V for –55°C ≤ T
A
≤ 50°C, and V
ON/OFF
= 0.2V for
50°C ≤ T
A
≤ 125°C. (LT1080 only)
Note 4: Unless otherwise specified, V
CC
= 5V, external loading of V
+
and
V
–
equals zero and the driver outputs are low (inputs high).
Note 5: Time from either SHUTDOWN high or power on until V
+
≥ 6V and
V
–
≤ –6V. All external capacitors are 1µF.
Note 6: Data rate operation guaranteed by slew rate, short-circuit current
and propagation delay tests.
temperature range, otherwise specifications are at TA = 25°C. (Note 2)
4
LT1080/LT1081
10801fe
PI FU CTIO S
UUU
(Pin numbers refer to LT1080)
TEMPERATURE (°C)
–55 –25 0 25 50 75 100 125
DRIVER OUTPUT VOLTAGE (V)
1080/81 G01
10
8
6
4
2
0
–2
–4
–6
–8
–10
V
CC
= 5.5V
V
CC
= 4.5V
R
L
= 3k
OUTPUT HIGH
V
CC
= 5.5V
V
CC
= 4.5V
OUTPUT LOW
V
CC
= 5V
V
CC
= 5V
TIME (ms)
0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
SUPPLY VOLTAGE (V)
1080/81 G03
10
8
6
4
2
0
–2
–4
–6
–8
–10
V
+
SUPPLY
V
CC
= 5V
C1 TO C4 = 1µF
R
L
= 4.7k; V
+
TO V
–
V
–
SUPPLY
OUTPUT CURRENT (mA)
02468101214161820
OUTPUT VOLTAGE (V)
1080/81 G02
10
8
6
4
2
0
–2
–4
–6
–8
–10
V
CC
= 5V
V
+
OUTPUT VOLTAGE
LOADED TO V
–
LOADED TO GROUND
LOADED TO GROUND
LOADED TO V
+
V
–
OUTPUT VOLTAGE
Driver Output Voltage Supply Generator Outputs
Supply Generation from VCC
or Shutdown
C1
+
; C1
–
; C2
+
; C2
–
(Pins 2, 4, 5, 6): Requires an external
capacitor (≥1µF) from C1
+
to C1
–
and another from C2
+
to C2
–
. Pin 2 can be used for connecting a second positive
supply. When a separate positive supply is used, C1 can be
deleted.
V
+
(Pin 3): Positive Supply for RS232 Drivers.
V
+
≈ 2V
CC
– 1.5V. Requires an exterenal capacitor (≥1µF)
for charge storage. May be loaded (up to 15mA) for
external system use. Loading does reduce V
+
voltage (see
graphs). Capacitor may be tied to ground or +5V input
supply. With multiple transceivers, the V
+
and V
–
pins may
be paralleled into common capacitors.
V
–
(Pin 7): Negative Supply for RS232 Drivers.
V
–
≈ –(2V
CC
– 2.5V). Requires an external capacitor
(≥1µF) for charge stroage. May be loaded (up to –15mA)
for external system use. Loading does reduce V
–
voltage
(see graphs). With multiple transceivers, the V
+
and V
–
pins may be paralleled into common capacitors.
TR2 OUT; TR1 OUT (Pins 8, 15): Driver Outputs with
RS232 Voltage Levels. Outputs are in a high impedance
state when in the SHUTDOWN mode or when power is off
(V
CC
= 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. Shorting one output will affect output from the
other.
REC2 IN; REC1 IN (Pins 9, 14): Receiver Inputs. Accepts
RS232 voltage levels (±30V) and has 0.4V of hysteresis to
provide noise immunity. Input impedance is nominally
5kΩ.
REC2 OUT; REC1 OUT (Pins 10, 13): 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 or V
CC
with power on, off or in the SHUTDOWN
mode.
TR2 IN; TR1 IN (Pins 11, 12): RS232 Driver Input Pins.
Inputs are TTL/CMOS compatible. Inputs should not be
allowed to float. Tie unused inputs to V
CC
.
GND (Pin 16): Ground Pin.
V
CC
(Pin 17): Input Supply Pin. Supply current drops to
zero in the SHUTDOWN mode.
ON/OFF (Pin 18): Contols the operation mode of the
LT1080 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. A logic high fully
enables the device.
TYPICAL PERFOR A CE CHARACTERISTICS
UW
5
LT1080/LT1081
10801fe
TYPICAL PERFOR A CE CHARACTERISTICS
UW
TEMPERATURE (°C)
–55 –25 0 25 50 75 100 125
INPUT THRESHOLD (V)
1080/81 G04
3.00
2.75
2.50
2.25
2.00
1.75
1.50
1.25
1.00
0.75
0.50
INPUT HIGH
INPUT LOW
INPUT VOLTAGE (V)
012345
INPUT CURRENT (µA)
1080/81 G06
40
35
30
25
20
15
10
5
0
–5
–10
Receiver Input Thresholds
Receiver Output
Short-Circuit Current ON/OFF Pin Current vs Voltage
TEMPERATURE (°C)
OUTPUT CURRENT (mA)
100
10
1
0.1
1080/81 G05
OUTPUT SOURCING
OUTPUT SINKING
–55 –25 0 25 50 75 100 125
ON/OFF Pin Thresholds Supply Current in Shutdown
Driver Output Leakage in
Shutdown
TEMPERATURE (°C)
–55 –25 0 25 50 75 100 125
ON/OFF PIN VOLTAGE (V)
1080/81 G07
5.0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
MAXIMUM OFF VOLTAGE
MINIMUM ON VOLTAGE
TEMPERATURE (°C)
SUPPLY CURRENT (nA)
1000
100
10
1
1080/81 G08
VCC = 5V
–55 –25 0 25 50 75 100 125
TEMPERATURE (°C)
OUTPUT LEAKAGE CURRENT (µA)
100
10
1
0.1
1080/81 G09
VOUT = –30V
VOUT = 30V
–55 –25 0 25 50 75 100 125
Output Waveforms Shutdown to Receiver Output
02µs4µs6µs8µs 0 1ms 2ms 3ms 4ms 0 1ms 2ms 3ms 4ms
V
CC
= 5V 1080/81 G11.tiffV
CC
= 5V 1080/81 G11.tiff
R
L
= 3k
V
CC
= 5V 1080/81 G10.tiff
R
L
= 3k
5V
0V
RECEIVER
OUTPUT
LOW
0V
–5V
–10
ON/OFF
INPUT
10V
5V
0V
DRIVER
OUTPUT
HIGH
INPUT 5V
0V
DRIVER
OUTPUT
5V
0V
–5V
RECEIVER
OUTPUT
5V
0V
Shutdown to Driver Output
6V
4V
2V
0V
RECEIVER
OUTPUT
ON/OFF
INPUT
5V
0V
6
LT1080/LT1081
10801fe
APPLICATIO S I FOR ATIO
WUUU
The driver output stage of the LT1080 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. Some
drivers have diodes connected between the outputs and
the supplies, so externally applied voltages can cause
excessive supply voltage to develop.
Placing the LT1080 in the SHUTDOWN mode (Pin 18 low)
puts both the driver and receiver outputs in a high imped-
ance state. This allows data line sharing and transceiver
applications.
The SHUTDOWN mode also drops input supply current
(V
CC
; Pin 17) to zero for power-conscious systems.
1080/81 F03
LT1080 #1
DRIVER
LOGIC
TRANSMIT/RECEIVE
LINE
RS232
TRANSMIT/RECEIVE
LINE
LOGIC
INVERTER
ON/OFF
(TRANSMIT/
RECEIVE)
INPUT
LT1080 #2
RECEIVER
30V
–30V
OUTPUT CAN
BE FORCED
EXTERNALLY
1080/81 F01
LT1080/LT1081 Driver Transceiver
Sharing a Receiver Line Sharing a Transmitter Line
Older RS232 Drivers and CMOS Drivers
V
+
V
–
WITH SOME DRIVERS,
EXTERNALLY APPLIED
VOLTAGE CAN FORCE
THE SUPPLIES
1080/81 F02
LT1080 #1
RECEIVER
1080/81 F04
RS232
INPUT A
RS232
INPUT B
LOGIC
OUTPUT
LOGIC
INVERTER
ON/OFF
(CHANNEL
SELECT)
INPUT
LT1080 #2
RECEIVER
LT1080 #1
DRIVER
LOGIC
INPUT A
LOGIC
INPUT B
RS232
TRANSMISSION
LINE
LT1080 #2
DRIVER
1080/81 F05
LOGIC
INVERTER
ON/OFF
(CHANNEL
SELECT)
INPUT
7
LT1080/LT1081
10801fe
APPLICATIO S I FOR ATIO
WUUU
When driving CMOS logic from a receiver that will be used
in the SHUTDOWN mode and there is no other active
receiver on the line, a 51k resistor can be placed from the
logic input to V
CC
to force a definite logic level when the
receiver output is in a high impedance state.
The generated driver supplies (V
+
and V
–
) may be used to
power external circuitry such as other RS232 drivers or op
amps. They should be loaded with care, since excessive
loading can cause the generated supply voltages to drop,
causing the RS232 driver output voltages to fall below
RS232 requirements. See the graph “Supply Generator
Outputs” for a comparison of generated supply voltage
versus supply current.
1080/81 F08
DRIVER
V
+
3
EXTERNAL OP AMP
LT1080
V
–
V
+
V
–
7
1µF
1µF
–
+
GND
16
+
TYPICAL APPLICATIO
U
To protect against receiver input overloads in excess of
±30V, a voltage clamp can be placed on the data line and
still maintain RS232 compatibility.
RS232
INPUT
RECEIVER
LOGIC
OUTPUT
1080/81 F067
5k
1k*
30V
30V
* A PTC THERMISTOR WILL ALLOW
CONTINUOUS OVERLOAD OF GREATER THAN ±100V
Operating with 5V and 12V
LOGIC
INPUTS
LOGIC
OUTPUTS
ON/OFF 18
10
13
11
12
6
5
4
2
16
9
14
8
15
7
3
17 5V INPUT12V INPUT*
–12V OUTPUT
RS232 OUTPUT
RS232 OUTPUT
RS232 INPUT
RS232 INPUT
1080/81 • TA03
5k
5k
LT1080
1µF
1µF
* PIN 1 USED ON LT1081.
1080/81 F06
RS232
INPUT
ON/OFF
INPUT
LT1080
RECEIVER CMOS
LOGIC LOGIC
OUTPUT
V
CC
51k*
* FORCES LOGIC INPUT STATE WHEN V
ON/OFF
IS LOW
8
LT1080/LT1081
10801fe
J18 1298
0.015 – 0.060
(0.380 – 1.520)
0.100
(2.54)
BSC
0.014 – 0.026
(0.360 – 0.660)
0.045 – 0.065
(1.143 – 1.651)
0.200
(5.080)
MAX
0.125
(3.175)
MIN
0.008 – 0.018
(0.203 – 0.457) 0° – 15°
12345678
0.220 – 0.310
(5.590 – 7.870)
0.960
(24.384)
MAX
0.005
(0.127)
MIN 16 13
9
10
11
12
1415
17
18
0.025
(0.635)
RAD TYP
0.300 BSC
(0.762 BSC)
0.045 – 0.068
(1.143 – 1.727)
FULL LEAD
OPTION
0.023 – 0.045
(0.584 – 1.143)
HALF LEAD
OPTION
CORNER LEADS OPTION
(4 PLCS)
NOTE: LEAD DIMENSIONS APPLY TO SOLDER DIP/PLATE
OR TIN PLATE LEADS
J16 1298
0.015 – 0.060
(0.380 – 1.520)
0.100
(2.54)
BSC
0.014 – 0.026
(0.360 – 0.660)
0.045 – 0.065
(1.143 – 1.651)
0.200
(5.080)
MAX
0.125
(3.175)
MIN
0.008 – 0.018
(0.203 – 0.457) 0° – 15°
12345678
0.220 – 0.310
(5.588 – 7.874)
0.840
(21.336)
MAX
0.005
(0.127)
MIN 16 13 9
10
11121415
0.025
(0.635)
RAD TYP
0.300 BSC
(0.762 BSC)
0.045 – 0.068
(1.143 – 1.727)
FULL LEAD
OPTION
0.023 – 0.045
(0.584 – 1.143)
HALF LEAD
OPTION
CORNER LEADS OPTION
(4 PLCS)
NOTE: LEAD DIMENSIONS APPLY TO SOLDER DIP/PLATE
OR TIN PLATE LEADS
PACKAGE DESCRIPTIO
U
J Package
16-Lead CERDIP (Narrow .300 Inch, Hermetic)
(Reference LTC DWG # 05-08-1110)
J Package
18-Lead CERDIP (Narrow .300 Inch, Hermetic)
(Reference LTC DWG # 05-08-1110)
OBSOLETE PACKAGES
9
LT1080/LT1081
10801fe
PACKAGE DESCRIPTIO
U
N18 1098
0.020
(0.508)
MIN
0.125
(3.175)
MIN
0.130 ± 0.005
(3.302 ± 0.127)
0.065
(1.651)
TYP
0.045 – 0.065
(1.143 – 1.651)
0.018 ± 0.003
(0.457 ± 0.076)
0.005
(0.127)
MIN
0.100
(2.54)
BSC
0.255 ± 0.015*
(6.477 ± 0.381)
0.900*
(22.860)
MAX
18
123456789
1011
121314
16 1517
0.009 – 0.015
(0.229 – 0.381)
0.300 – 0.325
(7.620 – 8.255)
0.325 +0.035
–0.015
+0.889
–0.381
8.255
()
*THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS.
MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm)
N Package
16-Lead PDIP (Narrow .300 Inch)
(Reference LTC DWG # 05-08-1510)
N Package
18-Lead PDIP (Narrow .300 Inch)
(Reference LTC DWG # 05-08-1510)
N16 1098
0.255 ± 0.015*
(6.477 ± 0.381)
0.770*
(19.558)
MAX
16
12345678
910
11
12
13
14
15
0.020
(0.508)
MIN
0.125
(3.175)
MIN
0.130 ± 0.005
(3.302 ± 0.127)
0.065
(1.651)
TYP
0.045 – 0.065
(1.143 – 1.651)
0.018 ± 0.003
(0.457 ± 0.076)
0.100
(2.54)
BSC
0.009 – 0.015
(0.229 – 0.381)
0.300 – 0.325
(7.620 – 8.255)
0.325 +0.035
–0.015
+0.889
–0.381
8.255
()
*THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS.
MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm)
10
LT1080/LT1081
10801fe
PACKAGE DESCRIPTIO
U
S16 (WIDE) 1098
NOTE 1
0.398 – 0.413*
(10.109 – 10.490)
16 15 14 13 12 11 10 9
12345678
0.394 – 0.419
(10.007 – 10.643)
0.037 – 0.045
(0.940 – 1.143)
0.004 – 0.012
(0.102 – 0.305)
0.093 – 0.104
(2.362 – 2.642)
0.050
(1.270)
BSC 0.014 – 0.019
(0.356 – 0.482)
TYP
0° – 8° TYP
NOTE 1
0.009 – 0.013
(0.229 – 0.330)
0.016 – 0.050
(0.406 – 1.270)
0.291 – 0.299**
(7.391 – 7.595)
× 45°
0.010 – 0.029
(0.254 – 0.737)
NOTE:
1. PIN 1 IDENT, NOTCH ON TOP AND CAVITIES ON THE BOTTOM OF PACKAGES ARE THE MANUFACTURING OPTIONS.
THE PART MAY BE SUPPLIED WITH OR WITHOUT ANY OF THE OPTIONS
DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE
DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE
*
**
SW Package
16-Lead Plastic Small Outline (Wide .300 Inch)
(Reference LTC DWG # 05-08-1620)
11
LT1080/LT1081
10801fe
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen-
tation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
PACKAGE DESCRIPTIO
U
S18 (WIDE) 1098
NOTE 1
0.447 – 0.463*
(11.354 – 11.760)
15 14 13 12 11 10
16
9
12345678
0.394 – 0.419
(10.007 – 10.643)
1718
0.037 – 0.045
(0.940 – 1.143)
0.004 – 0.012
(0.102 – 0.305)
0.093 – 0.104
(2.362 – 2.642)
0.050
(1.270)
BSC 0.014 – 0.019
(0.356 – 0.482)
TYP
0° – 8° TYP
NOTE 1
0.009 – 0.013
(0.229 – 0.330)
0.016 – 0.050
(0.406 – 1.270)
0.291 – 0.299**
(7.391 – 7.595)
× 45°
0.010 – 0.029
(0.254 – 0.737)
NOTE:
1. PIN 1 IDENT, NOTCH ON TOP AND CAVITIES ON THE BOTTOM OF PACKAGES ARE THE MANUFACTURING OPTIONS.
THE PART MAY BE SUPPLIED WITH OR WITHOUT ANY OF THE OPTIONS
DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE
DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE
*
**
SW Package
18-Lead Plastic Small Outline (Wide .300 Inch)
(Reference LTC DWG # 05-08-1620)
12
LT1080/LT1081
10801fe
LT/CPI 1101 1.5K REV E • PRINTED IN USA
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900
●
FAX: (408) 434-0507
●
www.linear.com
LINEAR TECHNOLOGY CORPORATION 1991
TYPICAL APPLICATIO
U
Supporting an LT1039 (Triple Driver/Receiver)
30k
30k
RS232 OUTPUT
RS232 OUTPUT
RS232 INPUT
RS232 INPUT
1080/81 • TA02
LT1039
TTL INPUT
30k
RS232 INPUT
VCC
TTL INPUT
TTL INPUT
TTL OUTPUT
TTL OUTPUT
TTL OUTPUT
ON/OFF
RS232 OUTPUT
5k
RS232 OUTPUT
RS232 INPUT
LT1080
TTL INPUT
5k
RS232 INPUT
VCC
TTL INPUT
TTL OUTPUT
TTL OUTPUT
ON/OFF
RS232 OUTPUT
1µF
2
*C1
4
1µF
5
6
3
7
18 17
1µF1µF
GND
16
GND
10
V+
V–
1
9
18 17
5V
SHUTDOWN
C2–
C2+
C1–
C1+
V+
V–
*IN APPLICATIONS WHERE A SEPARATE SECOND POSITIVE SUPPLY IS AVAILABLE
(SUCH AS 5V AND 12V), THE 12V SUPPLY MAY BE CONNECTED TO PIN 2 AND
C1 DELETED. THE POWER SUPPLY CIRCUITRY WILL THEN INVERT THE 12V SUPPLY.
THE 5V SUPPLY IS STILL NEEDED TO POWER THE BIASING CIRCUITRY AND RECEIVERS.
PART NUMBER DESCRIPTION COMMENTS
LT1180A/LT1181A 5V Low Power 2DR/2TX RS232 Transceiver 0.1µF Capacitors, 10kV ESD
LT1780/LT1781 5V Low Power 2DR/2TX RS232 Transceiver 15kV ESD
LT1381 5V Low Power 2DR/2TX RS232 Transceiver 16-Pin Narrow SO Package
LT1130A/LT1140A 5V RS232 Transceivers Up to 5DR/5RX
LTC1383 5V Low Power 2DR/2RX RS232 Transceiver Low Supply Current I
CC
= 220µA
LTC1386 3.3V Low Power EIA/TIA562 Transceiver Low Supply Current I
CC
= 200µA
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