LINER LTC1382_1

LTC1382
5V Low Power
RS232 Transceiver
with Shutdown
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FEATURES
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DESCRIPTIO
The LTC®1382 is an ultra-low power 2-driver/2-receiver
RS232 transceiver that operates from a single 5V
supply. The charge pump requires only four spacesaving 0.1µF capacitors.
Operates from a Single 5V Supply
Low Supply Current: ICC = 220µA
ICC = 0.2µA in Shutdown Mode
ESD Protection Over ±10kV
Uses Small Capacitors: 0.1µF
Operates to 120kBaud
Output Overvoltage Does Not Force Current
Back into Supplies
RS232 I/O Lines Can Be Forced to ±25V
Without Damage
Pin Compatible with LT1180A
The transceiver operates in one of two modes, Normal
and Shutdown. In the Normal mode, ICC is only 220µA
with the driver outputs unloaded. In the Shutdown
mode, the charge pump is turned off, the driver outputs
are forced into three-state, both receivers are off and
ICC drops to 0.2µA.
The LTC1382 is fully compliant with all data rate and
overvoltage RS232 specifications. The transceiver can
operate up to 120kbaud with a 2500pF, 3kΩ load. Both
driver outputs and receiver inputs can be forced to
±25V without damage and can survive multiple ±10kV
ESD strikes.
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APPLICATIO S
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Notebook Computers
Palmtop Computers
, LTC and LT are registered trademarks of Linear Technology Corporation.
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TYPICAL APPLICATIO
2-Drivers/2-Receivers with Shutdown
2
17
4
3
5
LOGIC INPUT
6
0.1µF
0.1µF
12
15
232 OUTPUT
VCC
300k
LOGIC INPUT
LOGIC OUTPUT
LOGIC OUTPUT
ON/OFF
11
8
13
14
5k
10
18
9
5k
16
1.2
TEST CONDITION: VCC = 5V
7
VCC
300k
600
232 OUTPUT
232 INPUT
232 INPUT
500
1.0
400
0.8
300
0.6
QUIESCENT
CURRENT
200
0.4
SHUTDOWN
CURRENT
100
0
–20
0
20
40
TEMPERATURE (°C)
SHUTDOWN CURRENT (µA)
0.1µF
LTC1382
VCC = 5V
QUIESCENT CURRENT (µA)
0.1µF
Quiescent and Shutdown Supply Current
vs Temperature
0.2
60
80
0
LTC1382 • TA02
LTC1382 • TA01
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LTC1382
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AXI U
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ABSOLUTE
RATI GS
Supply Voltage (VCC) ................................................ 6V
Input Voltage
Driver ....................................... – 0.3V to V CC + 0.3V
Receiver ............................................... – 25V to 25V
Digital Input ............................... – 0.3V to VCC + 0.3V
Output Voltage
Driver .................................................... – 25V to 25V
Receiver .................................... – 0.3V to VCC + 0.3V
Short-Circuit Duration
V + ................................................................... 30 sec
V – ................................................................... 30 sec
Driver Output .............................................. Indefinite
Receiver Output .......................................... Indefinite
Operating Temperature Range
LTC1382C ............................................... 0°C to 70°C
LTC1382I ............................................ – 40°C to 85°C
Storage Temperature Range ................ – 65°C to 150°C
Lead Temperature (Soldering, 10 sec)................. 300°C
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PACKAGE/ORDER I FOR ATIO
ORDER PART
NUMBER
TOP VIEW
NC 1
18 ON/OFF
C1+ 2
17 VCC
+
16 GND
V
3
C1– 4
15 TR1 OUT
C2+ 5
14 RX1 IN
C2– 6
13 RX1 OUT
V– 7
12 TR1 IN
TR2 OUT 8
11 TR2 IN
RX2 IN 9
N PACKAGE
18-LEAD PDIP
LTC1382CN
LTC1382CSW
LTC1382IN
LTC1382ISW
10 RX2 OUT
SW PACKAGE
18-LEAD PLASTIC SO
TJMAX = 125°C, θJA = 65°C/W (N)
TJMAX = 125°C, θJA = 85°C/W (S)
Consult LTC Marketing for parts specified with wider operating temperature
ranges.
DC ELECTRICAL CHARACTERISTICS
The ● denotes specifications which apply over the full operating
temperature range. VCC = 5V, C1 = C2 = C3 = C4 = 0.1µF, VON/OFF = VCC, unless otherwise noted.
PARAMETER
CONDITIONS
Any Driver
Output Voltage Swing
3k to GND
Logic Input Voltage Level
Logic Input Current
Output Short-Circuit Current
Output Leakage Current
Any Receiver
Input Voltage Thresholds
Hysteresis
Input Resistance
Output Voltage
Output Short-Circuit Current
Output Leakage Current
MIN
TYP
●
●
5.0
– 5.0
Input Low Level (VOUT = High)
Input High Level (VOUT = Low)
VIN = VCC
VIN = 0V
VOUT = 0V
Shutdown or VCC = 0V (Note 3), VOUT = ±10V
●
●
2.0
7.0
– 6.5
1.4
1.4
Input Low Threshold
Input High Threshold
●
●
0.8
●
0.1
3
– 10V ≤ VIN ≤ 10V
Output Low, IOUT = – 1.6mA (VCC = 5V)
Output High, IOUT = 160µA (VCC = 5V)
Sinking Current, VOUT = VCC
Sourcing Current VOUT = 0V
Shutdown (Note 3), 0V ≤ VOUT ≤ VCC
Positive
Negative
●
●
±9
●
●
●
●
3.0
– 15
10
– 20
±12
±10
1.3
1.7
0.4
5
0.2
3.2
– 40
20
1
MAX
0.8
5
– 40
±500
2.4
1
7
0.4
10
UNITS
V
V
V
V
µA
µA
mA
µA
V
V
V
kΩ
V
V
mA
mA
µA
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LTC1382
DC ELECTRICAL CHARACTERISTICS
The ● denotes specifications which apply over the full operating
temperature range. VCC = 5V, C1 = C2 = C3 = C4 = 0.1µF, VON/OFF = VCC, unless otherwise noted.
PARAMETER
Power Supply Generator
V + Output Voltage
CONDITIONS
MIN
IOUT = 0mA
IOUT = 8mA
IOUT = 0mA
IOUT = – 8mA
Shutdown to Turn-On
V – Output Voltage
Supply Rise Time
Power Supply
VCC Supply Current
MAX
UNITS
8.0
7.5
– 8.0
– 7.0
0.2
No Load (Note 2), 0°C to 70°C
No Load (Note 2), – 40°C to 85°C
Shutdown (Note 3)
Supply Leakage Current (VCC)
Digital Input Threshold Low
Digital Input Threshold High
TYP
●
●
●
●
2.0
●
0.22
0.35
0.2
1.4
1.4
V
V
V
V
ms
0.5
1.0
10
0.8
mA
mA
µA
V
V
AC CHARACTERISTICS
The ● denotes specifications which apply over the full operating temperature range.
VCC = 5V, C1 = C2 = C3 = C4 = 0.1µF, unless otherwise noted.
PARAMETER
Slew Rate
CONDITIONS
RL = 3k, CL = 51pF
RL = 3k, CL = 2500pF
t HLD (Figure 1)
t LHD (Figure 1)
t HLR (Figure 2)
t LHR (Figure 2)
Driver Propagation Delay
(TTL to RS232)
Receiver Propagation Delay
(RS232 to TTL)
MIN
3
●
●
●
●
Note 1: Absolute Maximum Ratings are those values beyond which the life
of the device may be impaired.
Note 2: Supply current is measured with driver and receiver outputs
unloaded.
TYP
8
5
2
2
0.3
0.3
MAX
30
UNITS
V/µs
V/µs
µs
µs
µs
µs
3.5
3.5
0.8
0.8
Note 3: Measurements made in the Shutdown mode are performed
with VON/OFF = 0V.
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TYPICAL PERFOR A CE CHARACTERISTICS
Driver Output Voltage
vs Temperature
DRIVER OUTPUT VOLTAGE (V)
6
OUTPUT HIGH
VCC = 5V
2.0
VCC = 4.5V
4
2
0
–2
OUTPUT LOW
VCC = 4.5V
–4
–6
VTH
1.8
1.6
VTL
1.4
1.0
20
30
40
50
TEMPERATURE (°C)
30
25
20
15
10
5
–8
10
35
1.2
VCC = 5V
0
VCC = 5V
RL = 3k
CL = 2500pF
2 DRIVERS ACTIVE
40
SUPPLY CURRENT (mA)
RL = 3k
8
Supply Current vs Data Rate
45
2.2
THRESHOLD VOLTAGE (V)
10
Receiver Input Thresholds
vs Temperature
60
70
LTC1382 • TPC01
0
0
10
40
30
50
20
TEMPERATURE (˚C)
60
70
LTC1382 • TPC02
0
25
50
75
100 125
DATA RATE (kBAUD)
150
175
LTC1382 • TPC03
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LTC1382
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TYPICAL PERFOR A CE CHARACTERISTICS
Driver Short-Circuit Current
vs Temperature
18
16
16
14
12
2 DRIVERS LOADED
RL = 3k
10
8
1 DRIVER LOADED
RL = 3k
6
4
2
Receiver Short-Circuit Current
vs Temperature
50
SHORT-CIRCUIT CURRENT (mA)
18
SHORT-CIRCUIT CURRENT (mA)
SUPPLY CURRENT (mA)
VCC Supply Current
vs Temperature
–
14
ISC
12
ISC+
10
8
6
4
40
ISC–
30
20
ISC+
2
0
10
0
0
10
20
30
40
50
TEMPERATURE (°C)
60
70
0
10
20
30
40
50
TEMPERATURE (°C)
LTC1382 • TPC04
60
0
70
30
20
50
40
TEMPERATURE (°C)
60
70
LTC1382 • TPC06
LTC1382 • TPC05
Driver Leakage in Shutdown
vs Temperature
10
Driver Output Waveforms
Receiver Output Waveforms
45
DRIVER
OUTPUT
RL = 3k
CL = 2500pF
LEAKAGE CURRENT (µA)
40
35
30
25
RECEIVER
OUTPUT
CL = 51pF
DRIVER
OUTPUT
RL = 3k
VOUT = –20V
INPUT
20
INPUT
15
10
VOUT = 20V
5
LTC1382 • TPC08
LTC1382 • TPC09
0
0
10
30
20
40
50
TEMPERATURE (°C)
60
70
LTC1349 • TPC05
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LTC1382
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PI FU CTIO S
VCC: 5V Input Supply Pin. This pin should be decoupled
with a 0.1µF ceramic capacitor.
charge pump efficiency, the capacitor’s effective series
resistance should be less than 2Ω.
GND: Ground Pin.
TR IN: RS232 Driver Input Pins. Inputs are TTL/CMOS
compatible. The inputs of unused drivers can be left
unconnected since 300k input pull-up resistors to VCC are
included on chip. To minimize power consumption, the
internal driver pull-up resistors are disconnected from VCC
in the Shutdown mode.
ON/OFF: TTL/CMOS Compatible Shutdown Pin. A logic
low puts the device in the Shutdown mode. Both driver
outputs are forced into three-state and the supply current
is 0.2µA.
V +: Positive Supply Output (RS232 Drivers). V + ≅ 2VCC –
2V. This pin requires an external capacitor C = 0.1µF for
charge storage. The capacitor may be tied to ground or
VCC. With multiple devices, the V + and V – pins may share
a common capacitor. For large numbers of devices, increasing the size of the shared common storage capacitors is recommended to reduce ripple.
V –: Negative Supply Output (RS232 Drivers). V – ≅ – (2VCC
– 2V). This pin requires an external capacitor C = 0.1µF for
charge storage.
C1+, C1–, C2+, C2–: Commutating Capacitor Inputs. These
pins require two external capacitors C = 0.1µF: one from
C1+ to C1– and another from C2+ to C2 –. To maintain
TR OUT: Driver Outputs at RS232 Voltage Levels. Outputs
are in a high impedance state when in the Shutdown or
VCC = 0V. The driver outputs are protected against ESD to
±10kV for human body model discharges.
RX IN: Receiver Inputs. These pins can be forced to ±25V
without damage. The receiver inputs are protected against
ESD to ±10kV for human body model discharges. Each
receiver provides 0.4V of hysteresis for noise immunity.
RX OUT: Receiver Outputs with TTL/CMOS Voltage Levels. Outputs are in a high impedance state when in the
Shutdown mode.
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SWITCHI G TI E WAVEFOR S
DRIVER
INPUT
VCC
1.4V
1.4V
0V
V+
DRIVER
OUTPUT
0V
0V
t LHD
V–
1.7V
RX
INPUT
RX
OUTPUT
0V
2.4V
0.8V
t LHR
t HLD
VCC
1.3V
t HLR
LTC1382 • F01
Figure 1. Driver Propagation Delay Timing
VCC
0V
LTC1382 • F02
Figure 2. Receiver Propagation Delay Timing
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LTC1382
TEST CIRCUITS
Receiver Timing Test Load
Driver Timing Test Load
DRIVER
INPUT
DRIVER
OUTPUT
RX
OUTPUT
RX INPUT
DRIVER
51pF
RX
3k
51pF
LTC1382 • TA04
LTC1382 • TA03
ESD Test Circuit
0.1µF
2
17
4
3
5
0.1µF
LOGIC INPUT
6
LTC1382
VCC = 5V
0.1µF
7
0.1µF
VCC
300k
12
15
232 OUTPUT
VCC
300k
LOGIC INPUT
LOGIC OUTPUT
LOGIC OUTPUT
ON/OFF
11
8
13
14
5k
10
18
9
5k
232 OUTPUT
232 INPUT
RS232
LINE PINS
PROTECTED
TO ±10kV
232 INPUT
16
LTC1382 • TA05
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LTC1382
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PACKAGE DESCRIPTIO
N Package
18-Lead PDIP (Narrow .300 Inch)
(Reference LTC DWG # 05-08-1510)
.900*
(22.860)
MAX
18
17
16
15
14
13
12
11
10
1
2
3
4
5
6
7
8
9
.255 ± .015*
(6.477 ± 0.381)
.300 – .325
(7.620 – 8.255)
.130 ± .005
(3.302 ± 0.127)
.020
(0.508)
MIN
.009 – .015
(0.229 – 0.381)
.065
(1.651)
TYP
+.035
.325 –.015
(
8.255
+0.889
–0.381
.045 – .065
(1.143 – 1.651)
.125
(3.175)
MIN
)
.005
(0.127)
MIN
.018 ± .003
(0.457 ± 0.076)
.100
(2.54)
BSC
NOTE:
1. DIMENSIONS ARE
INCHES
MILLIMETERS
*THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS.
MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .010 INCH (0.254mm)
N18 0502
SW Package
18-Lead Plastic Small Outline (Wide .300 Inch)
(Reference LTC DWG # 05-08-1620)
.050 BSC .045 ±.005
.030 ±.005
TYP
.447 – .463
(11.354 – 11.760)
NOTE 4
N
18
17
16
15
14
13
12
11
10
N
.325 ±.005
.420
MIN
.394 – .419
(10.007 – 10.643)
NOTE 3
1
2
3
N/2
N/2
RECOMMENDED SOLDER PAD LAYOUT
.291 – .299
(7.391 – 7.595)
NOTE 4
.010 – .029 × 45°
(0.254 – 0.737)
.005
(0.127)
RAD MIN
1
2
3
4
5
6
7
.093 – .104
(2.362 – 2.642)
8
9
.037 – .045
(0.940 – 1.143)
0° – 8° TYP
.009 – .013
(0.229 – 0.330)
NOTE:
1. DIMENSIONS IN
NOTE 3
.016 – .050
(0.406 – 1.270)
.050
(1.270)
BSC
.004 – .012
(0.102 – 0.305)
.014 – .019
(0.356 – 0.482)
TYP
INCHES
(MILLIMETERS)
2. DRAWING NOT TO SCALE
3. 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
4. THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS.
MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .006" (0.15mm)
S18 (WIDE) 0502
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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 representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
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LTC1382
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PART NUMBER
DESCRIPTION
COMMENTS
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±15kV ESD per IEC 1000-4
LTC1383
5V, 2 Driver, 2 Receiver RS232 Transceiver
220µA Supply Current, Narrow 16-pin SO
LTC1384
5V, 2 Driver, 2 Receiver RS232 Transceiver
220µA Supply Current, 2 Receivers Active in Shutdown
LTC1385
3.3V, 2 Driver, 2 Receiver RS562 Transceiver
220µA Supply Current, 2 Receivers Active in Shutdown
LTC1386
3.3V, 2 Driver, 2 Receiver RS562 Transceiver
220µA Supply Current, Narrow 16-pin SO
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Linear Technology Corporation
LW/TP 1002 1K REV A • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7487
(408) 432-1900 ● FAX: (408) 434-0507 ● linear.com
 LINEAR TECHNOLOGY CORPORATION 1994