LINER LTC1347_1

LTC1347
5V Low Power RS232
3-Driver/5-Receiver Transceiver
with 5 Receivers Active
in Shutdown
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FEATURES
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DESCRIPTIO
The LTC®1347 is a 3-driver/5-receiver RS232 transceiver
with very low supply current. In the no load condition, the
supply current is only 300µA. The charge pump only
requires four 0.1µF capacitors.
Low Supply Current: 300µA
Five Receivers Kept Alive in Shutdown
ESD Protection Over ±10kV
Operates from a Single 5V Supply
Uses Small Capacitors: 0.1µF
Operates to 120kBaud
Three-State Outputs Are High Impedance When Off
Output Overvoltage Does Not Force Current Back
into Supplies
RS232 I/O Lines Can Be Forced to ±25V
Without Damage
Pin Compatible with LT1137A and LT1237
Flowthrough Architecture
In Shutdown mode, all five receivers are kept alive and the
supply current is 80µA. All RS232 outputs assume a high
impedance state in Shutdown and with the power off.
The LTC1347 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
Quiescent and Shutdown Supply Current
vs Temperature
3-Drivers/5-Receivers with Shutdown
VCC
C2
0.1µF
DRIVER 1 OUT
RX1 IN
DRIVER 2 OUT
RX2 IN
RX3 IN
RX4 IN
DRIVER 3 OUT
RX5 IN
ON/OFF
NC
2
28
LTC1347
27
3
26
4
25
5
24
6
23
7
22
8
21
9
20
10
19
11
18
12
17
13
16
14
15
120
1200
V–
C3
0.1µF
C4
0.1µF
DRIVER 1 IN
RX1 OUT
DRIVER 2 IN
RX2 OUT
RX3 OUT
RX4 OUT
100
1000
SHUTDOWN
CURRENT
800
80
60
600
QUIESCENT
CURRENT
400
40
SHUTDOWN CURRENT (µA)
C1
0.1µF
1
QUIESCENT CURRENT (µA)
V+
20
200
DRIVER 3 IN
0
0
80 100
20
60
40
TEMPERATURE (°C)
TEST CONDITION:
VCC = 5V, ALL DRIVER INPUTS TIED TO VCC.
0
–40
RX5 OUT
GND
NC
NC
–20
1347 TA02
1347 TA01
1347fa
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LTC1347
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ABSOLUTE
RATI GS
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PACKAGE/ORDER I FOR ATIO
Supply Voltage (VCC) ................................................ 6V
Input Voltage
Driver ....................................... – 0.3V to V CC + 0.3V
Receiver ............................................... – 25V to 25V
On/Off Pin .................................. – 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 .................... 0°C to 70°C
Storage Temperature Range ................ – 65°C to 150°C
Lead Temperature (Soldering, 10 sec)................. 300°C
TOP VIEW
V+
1
ORDER PART
NUMBER
28 V–
VCC 2
27 C2+
C1+ 3
26 C2–
C1– 4
25 DR1 IN
DR1 OUT 5
24 RX1 OUT
RX1 IN 6
23 DR2 IN
DR2 OUT 7
22 RX2 OUT
RX2 IN 8
21 RX3 OUT
RX3 IN 9
20 RX4 OUT
RX4 IN 10
19 DR3 IN
DR3 OUT 11
LTC1347CG
LTC1347CNW
LTC1347CSW
18 RX5 OUT
RX5 IN 12
17 GND
ON/OFF 13
16 NC
NC 14
15 NC
G PACKAGE
28-LEAD SSOP
NW PACKAGE
28-LEAD PDIP
SW PACKAGE
28-LEAD PLASTIC SO
TJMAX = 125°C, θJA = 96°C/W (G)
TJMAX = 125°C, θJA = 56°C/W (NW)
TJMAX = 125°C, θJA = 85°C/W (SW)
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, 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
MIN
TYP
●
●
5.0
– 5.0
Input Low Level (VOUT = High)
Input High Level (VOUT = Low)
VIN = 5V
VIN = 0V
VOUT = 0V
Shutdown, VOUT = ±20V (Note 3)
●
●
2.0
7.0
– 6.5
1.4
1.4
Input Low Threshold
Input High Threshold
VIN = ±10V
Output Low, IOUT = – 1.6mA (VCC = 5V)
Output High, IOUT = 160µA (VCC = 5V)
Sinking Current, VOUT = VCC
Sourcing Current, VOUT = 0V
Positive
Negative
0.8
5
–5
●
●
±9
±10
±12
±500
●
●
0.8
●
0.1
3
1.3
1.7
0.4
5
0.2
4.8
– 40
20
●
●
MAX
3.5
– 15
10
UNITS
V
V
V
V
µA
µA
mA
µA
2.4
1.0
7
0.4
V
V
V
kΩ
V
V
mA
mA
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LTC1347
DC ELECTRICAL CHARACTERISTICS
The ● denotes specifications which apply over the full operating
temperature range. VCC = 5V, C1 = C2 = C3 = C4 = 0.1µF, unless otherwise noted.
PARAMETER
Power Supply Generator
V + Output Voltage
CONDITIONS
MIN
IOUT = 0mA
IOUT = 12mA
IOUT = 0mA
IOUT = – 12mA
Shutdown to Turn-On
V – Output Voltage
Supply Rise Time
Power Supply
VCC Supply Current
TYP
MAX
UNITS
8.0
7.5
– 8.0
– 7.0
0.2
No Load (All Drivers VIN = 5V)(Note 2)
No Load (All Drivers VIN = 0V) (Note 2)
Shutdown (Note 3)
0.6
0.8
80.0
1.4
1.4
●
●
●
On/Off Threshold Low
On/Off Threshold High
●
2.0
●
V
V
V
V
ms
1.1
1.3
120.0
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
0.2
MAX
30
3.5
3.5
0.8
0.8
UNITS
V/µs
V/µs
µs
µs
µs
µs
Note 3: Supply current and leakage current measurements in Shutdown
are performed with VON/OFF = 0V.
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TYPICAL PERFOR A CE CHARACTERISTICS
Driver Output Voltage
Receiver Input Thresholds
10
6
OUTPUT HIGH
VCC = 5V
VCC = 4.5V
4
2
0
–2
OUTPUT LOW
VCC = 4.5V
–4
1.8
VTH
1.6
VTL
1.4
1.2
–6
–20
20
0
40
60
TEMPERATURE (°C)
80
100
1347 G01
1.0
–40 –20
35
30
25
20
15
10
5
VCC = 5V
–8
–40
VCC = 5V
RL = 3k
CL = 2500pF
3 DRIVERS ACTIVE
40
2.0
SUPPLY CURRENT (mA)
RL = 3k
THRESHOLD VOLTAGE (V)
DRIVER OUTPUT VOLTAGE (V)
8
Supply Current vs Data Rate
45
2.2
0
40
20
60
0
TEMPERATURE (˚C)
80
100
1347 G02
0
25
75 100 125
50
DATA RATE (kBAUD)
150
175
1347 G03
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LTC1347
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TYPICAL PERFOR A CE CHARACTERISTICS
Driver Leakage in Shutdown
16
40
14
35
3 DRIVERS LOADED
RL = 3k
12
10
8
1 DRIVER LOADED
RL = 3k
6
4
2
18
30
25
VOUT = –20V
20
15
10
VOUT = 20V
5
0
Driver Short-Circuit Current
20
SHORT-CIRCUIT CURRENT (mA)
45
LEAKAGE CURRENT (µA)
SUPPLY CURRENT (mA)
VCC Supply Current
20
10
30
20
40
50
TEMPERATURE (°C)
70
60
0
10
30
20
40
50
TEMPERATURE (°C)
1347 G04
ISC–
14
ISC+
12
10
8
6
4
0
0
16
60
70
0
–40
–20
20
0
40
60
TEMPERATURE (°C)
1347 G05
Receiver Short-Circuit Current
80
100
1347 G06
Driver Output Waveforms
Receiver Output Waveforms
SHORT-CIRCUIT CURRENT (mA)
60
DRIVER
OUTPUT
RL = 3k
CL = 2500pF
50
40
RECEIVER
OUTPUT
CL = 51pF
DRIVER
OUTPUT
RL = 3k
ISC–
INPUT
30
INPUT
ISC+
20
1347 G08
10
–40 –20
40
20
0
60
TEMPERATURE (°C)
80
1347 G09
100
1347 G07
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PI FU CTIO S
VCC: 5V Input Supply Pin. Supply current is typically 80µA
in the Shutdown mode. This pin should be decoupled with
a 0.1µF ceramic capacitor.
GND: Ground Pin.
ON/OFF: TTL/CMOS Compatible Shutdown Pin. A logic
low puts the device in the Shutdown mode with all receivers kept alive, and the supply current is 80µA. All driver
outputs are in high impedance state. This pin cannot float.
V + : Positive Supply Output (RS232 Drivers).
V + ≅ 2VCC – 1V. 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 be paralleled into common capacitors. 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 – 1.5V). 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
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LTC1347
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PI FU CTIO S
charge pump efficiency, the capacitor’s effective series
resistance should be less than 2Ω.
DRIVER IN: RS232 Driver Input Pins. Inputs are TTL/
CMOS compatible. Inputs should not be allowed to float.
Tie unused inputs to VCC.
DRIVER OUT: Driver Outputs at RS232 Voltage Levels.
Outputs are in a high impedance state when in Shutdown
mode 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. All receivers are kept alive in Shutdown.
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SWITCHI G TI E WAVEFOR S
VCC
DRIVER
INPUT
1.4V
1.4V
0V
V+
DRIVER
OUTPUT
0V
0V
t LHD
V–
t HLD
1347 F01
Figure 1. Driver Propagation Delay Timing
VCC
1.7V
RX
INPUT
RX
OUTPUT
1.3V
0V
2.4V
0.8V
t LHR
t HLR
VCC
0V
1347 F02
Figure 2. Receiver Propagation Delay Timing
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LTC1347
TEST CIRCUITS
DRIVER
INPUT
DRIVER
OUTPUT
RX
OUTPUT
DRIVER
RX INPUT
51pF
RX
3k
51pF
1347 F04
1347 F03
Figure 3. Driver Timing Test Load
Figure 4. Receiver Timing Test Load
V+
C1
0.1µF
VCC
C2
0.1µF
DRIVER 1 OUT
RX1 IN
RS232
LINE PINS
PROTECTED
TO ±10kV
DRIVER 2 OUT
RX2 IN
RX3 IN
RX4 IN
DRIVER 3 OUT
RX5 IN
ON/OFF
NC
1
2
28
LTC1347
V–
27
3
26
4
25
5
24
6
23
7
22
8
21
9
20
10
19
11
18
12
17
13
16
14
15
C3
0.1µF
C4
0.1µF
DRIVER 1 IN
RX1 OUT
DRIVER 2 IN
RX2 OUT
RX3 OUT
RX4 OUT
DRIVER 3 IN
RX5 OUT
GND
NC
NC
1347 TC01
Figure 5. ESD Test Circuit
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LTC1347
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PACKAGE DESCRIPTIO
G Package
28-Lead Plastic SSOP (5.3mm)
(Reference LTC DWG # 05-08-1640)
9.90 – 10.50*
(.390 – .413)
28 27 26 25 24 23 22 21 20 19 18 17 16 15
1.25 ±0.12
7.8 – 8.2
5.3 – 5.7
0.42 ±0.03
7.40 – 8.20
(.291 – .323)
0.65 BSC
1 2 3 4 5 6 7 8 9 10 11 12 13 14
RECOMMENDED SOLDER PAD LAYOUT
5.00 – 5.60**
(.197 – .221)
2.0
(.079)
0° – 8°
0.09 – 0.25
(.0035 – .010)
0.65
(.0256)
BSC
0.55 – 0.95
(.022 – .037)
NOTE:
1. CONTROLLING DIMENSION: MILLIMETERS
MILLIMETERS
2. DIMENSIONS ARE IN
(INCHES)
0.05
(.002)
0.22 – 0.38
(.009 – .015)
G28 SSOP 0802
3. DRAWING NOT TO SCALE
*DIMENSIONS DO NOT INCLUDE MOLD FLASH. MOLD FLASH
SHALL NOT EXCEED .152mm (.006") PER SIDE
**DIMENSIONS DO NOT INCLUDE INTERLEAD FLASH. INTERLEAD
FLASH SHALL NOT EXCEED .254mm (.010") PER SIDE
NW Package
28-Lead PDIP (Wide .600 Inch)
(Reference LTC DWG # 05-08-1520)
1.455*
(36.957)
MAX
28
27
26
25
24
23
22
21
20
19
18
17
16
15
1
2
3
4
5
6
7
8
9
10
11
12
13
14
.505 – .560*
(12.827 – 14.224)
.600 – .625
(15.240 – 15.875)
.009 – .015
(0.229 – 0.381)
+.035
.625 –.015
(
15.87
+0.889
–0.381
NOTE:
1. DIMENSIONS ARE
)
.045 – .065
(1.143 – 1.651)
.150 ± .005
(3.810 ± 0.127)
.015
(0.381)
MIN
.070
(1.778)
TYP
.125
(3.175)
MIN
INCHES
MILLIMETERS
*THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS.
MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .010 INCH (0.254mm)
.035 – .080
(0.889 – 2.032)
.018 ± .003
(0.457 ± 0.076)
.100
(2.54)
BSC
NW28 0502
1347fa
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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LTC1347
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PACKAGE DESCRIPTIO
SW Package
28-Lead Plastic Small Outline (Wide .300 Inch)
(Reference LTC DWG # 05-08-1620)
.050 BSC .045 ±.005
.030 ±.005
TYP
.697 – .712
(17.70 – 18.08)
NOTE 4
N
28
27
26
25
24
23
22
21
20
19
18
17
16
15
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
8
9
10
11
12
13
14
.037 – .045
(0.940 – 1.143)
.093 – .104
(2.362 – 2.642)
0° – 8° TYP
.009 – .013
(0.229 – 0.330)
.050
(1.270)
BSC
NOTE 3
.016 – .050
(0.406 – 1.270)
NOTE:
1. DIMENSIONS IN
.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)
S28 (WIDE) 0502
RELATED PARTS
PART NUMBER
DESCRIPTION
COMMENTS
LT1137A
5V, 3 Driver, 5 Receiver RS232 Transceiver
±15kV ESD per IEC 1000-4
LTC1327
3.3V, 3 Driver, 5 Receiver RS562 Transceiver
300µA Supply Current, 0.2µA in Shutdown
LTC1337
5V, 3 Driver, 5 Receiver RS232 Transceiver
300µA Supply Current, 1µA in Shutdown
LTC1348
3.3V to 5V, 3 Driver, 5 Receiver RS232 Transceiver
True RS232 on 3.3V, 5 Receivers Active in Shutdown
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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
●
WWW.linear.com
 LINEAR TECHNOLOGY CORPORATION 1994