1350fa.pm7
1
LTC1350
1350fa
3.3V Low Power
EIA/TIA-562 3-Driver/
5-Receiver Transceiver
Low Supply Current: 300A
Receivers 4 and 5 Kept Alive
in Shutdown: 35A
ESD Protection: 10kV
Operates from a Single 3.3V Supply
Uses Small Capacitors: 0.1F
Operates to 120kBaud
Three-State Outputs are High Impedance
When Off
Output Overvoltage Does Not Force Current
Back into Supplies
EIA/TIA-562 I/O Lines Can Be Forced to 25V
Without Damage
Flowthrough Architecture
The LTC
1350 is a 3-driver/5-receiver EIA/TIA-562
transceiver with very low supply current. In the no load
condition, the supply current is only 300A. The charge
pump only requires four 0.1F capacitors.
In Shutdown mode, two receivers are kept alive and the
supply current is only 35A. All RS232 outputs assume
a high impedance state in Shutdown or with the power
off.
The LTC1350 is fully compliant with all data rate and
overvoltage EIA/TIA-562 specifications. The transceiver
can operate up to 120kbaud with a 1000pF and 3k load.
Both driver outputs and receiver inputs can be forced to
25V without damage and can survive multiple 10kV
ESD strikes.
Notebook Computers
Palmtop Computers
3-Drivers/5-Receivers with Shutdown
Quiescent and Shutdown Supply Current
vs Temperature
1
2
3
4
5
6
7
8
9
10
11
12
13
14
V
+
V
CC
C1
+
C1
DR1 OUT
RX1 IN
DR2 OUT
RX2 IN
RX3 IN
RX4 IN
DR3 OUT
RX5 IN
ON/OFF
NC
28
27
26
25
24
23
22
21
20
19
18
17
16
15
V
C2
+
C2
DR1 IN
RX1 OUT
DR2 IN
RX2 OUT
RX3 OUT
RX4 OUT
DR3 IN
RX5 OUT
GND
NC
NC
LTC1350
LTC1350 TA01
TEMPERATURE (C)
40
QUIESCENT CURRENT (
A)
400
500
600
20
60
LTC1350 TA02
300
200
20
0
40
80
100
100
0
TEST CONDITION: V
CC
= 3.3V
ALL DRIVER INPUTS TIED TO V
CC
SHUTDOWN CURRENT (
A)
65
75
85
55
45
35
0
QUIESCENT
CURRENT
SHUTDOWN CURRENT
FEATURES
APPLICATIO S
U
DESCRIPTIO
U
TYPICAL APPLICATIO
U
, LTC and LT are registered trademarks of Linear Technology Corporation.
2
LTC1350
1350fa
Supply Voltage (V
CC
) ................................................ 5V
Input Voltage
Driver ....................................... 0.3V to V
CC
+ 0.3V
Receiver ............................................... 25V to 25V
ON/OFF Pin ................................ 0.3V to V
CC
+ 0.3V
Output Voltage
Driver .................................................... 25V to 25V
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
Commercial (LTC1350C) ........................ 0C to 70C
Industrial (LTC1350I) ........................ 40C to 85C
Storage Temperature Range ................ 65C to 150C
Lead Temperature (Soldering, 10 sec)................. 300C
The
denotes specifications which apply over the full operating
temperature range. V
CC
= 3.3V, C1 = C2 = C3 = C4 = 0.1F, unless noted.
ABSOLUTE AXI U RATI GS
W
W
W
U
PACKAGE/ORDER I FOR ATIO
U
U
W
DC ELECTRICAL CHARACTERISTICS
ORDER PART
NUMBER
LTC1350CG
LTC1350CNW
LTC1350CSW
LTC1350IG
LTC1350INW
LTC1350ISW
T
JMAX
= 125C,
JA
= 96C/W (G)
T
JMAX
= 125C,
JA
= 56C/W (NW)
T
JMAX
= 125C,
JA
= 85C/W (SW)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
28
27
26
25
24
23
22
21
20
19
18
17
16
15
V
+
V
CC
C1
+
C1
DR1 OUT
RX1 IN
DR2 OUT
RX2 IN
RX3 IN
RX4 IN
DR3 OUT
RX5 IN
ON/OFF
NC
V
C2+
C2
DR1 IN
RX1 OUT
DR2 IN
RX2 OUT
RX3 OUT
RX4 OUT
DR3 IN
RX5 OUT
GND
NC
NC
NW PACKAGE
28-LEAD PDIP
TOP VIEW
SW PACKAGE
28-LEAD PLASTIC SO WIDE
G PACKAGE
28-LEAD SSOP
Consult LTC Marketing for parts specified with wider operating temperature
ranges.
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
Any Driver
Output Voltage Swing
3k to GND
Positive
3.7
4.5
V
Negative
3.7
4.5
V
Logic Input Voltage Level
Input Low Level (V
OUT
= High)
1.4
0.8
V
Input High Level (V
OUT
= Low)
2.0
1.4
V
Logic Input Current
V
IN
= V
CC
5
A
V
IN
= 0V
5
A
Output Short-Circuit Current
V
OUT
= 0V
9
10
mA
Output Leakage Current
Shutdown (Note 3), V
OUT
= 20V
10
500
A
Any Receiver
Input Voltage Thresholds
Input Low Threshold
0.8
1.3
V
Input High Threshold
1.7
2.4
V
Hysteresis
0.1
0.4
1
V
Input Resistance
V
IN
= 10V
3
5
7
k
Output Voltage
Output Low, I
OUT
= 1.6mA (V
CC
= 3.3V)
0.2
0.4
V
Output High, I
OUT
= 160A (V
CC
= 3.3V)
3.0
3.2
V
Output Short-Circuit Current
Sinking Current, V
OUT
= V
CC
3
20
mA
Output Leakage Current
Shutdown (Note 3), 0V V
OUT
V
CC
1
10
A
3
LTC1350
1350fa
The
denotes specifications which apply over the full operating
temperature range. V
CC
= 3.3V, C1 = C2 = C3 = C4 = 0.1F, unless noted.
The
denotes specifications which apply over the full operating temperature range.
V
CC
= 5V, C1 = C2 = C3 = C4 = 0.1F, unless noted.
Note 3: Supply current measurement in Shutdown mode is performed
with V
ON/OFF
= 0V.
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
Slew Rate
R
L
= 3k, C
L
= 51pF
8
30
V/s
R
L
= 3k, C
L
= 1000pF
3
5
V/s
Driver Propagation Delay
t
HLD
(Figure 1)
2
3.5
s
(TTL to EIA/TIA-562)
t
LHD
(Figure 1)
2
3.5
s
Receiver Propagation Delay
t
HLR
(Figure 2)
0.3
0.8
s
(EIA/TIA-562 to TTL)
t
LHR
(Figure 2)
0.3
0.8
s
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.
DC ELECTRICAL CHARACTERISTICS
AC CHARACTERISTICS
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
Power Supply Generator
V
+
Output Voltage
I
OUT
= 0mA
5.7
V
I
OUT
= 5mA
5.5
V
V
Output Voltage
I
OUT
= 0mA
5.3
V
I
OUT
= 5mA
5.0
V
Supply Rise Time
Shutdown to Turn-On
0.2
ms
Power Supply
V
CC
Supply Current
No Load (All Drivers V
IN
= V
CC
)(Note 2) 0C T
A
70C
0.3
0.6
mA
No Load (All Drivers V
IN
= 0)(Note 2) 0C T
A
70C
0.5
1.0
mA
No Load (All Drivers V
IN
= V
CC
)(Note 2) 0C T
A
85C
0.3
1.0
mA
No Load (All Drivers V
IN
= V
CC
)(Note 2) 40C T
A
0C
0.3
1.5
mA
No Load (All Drivers V
IN
= 0)(Note 2) 40C T
A
85C
0.5
1.5
mA
Shutdown (Note 3)
35
50
A
ON/OFF Threshold Low
1.4
0.8
V
ON/OFF Threshold High
2.0
1.4
V
4
LTC1350
1350fa
TYPICAL PERFOR A CE CHARACTERISTICS
U
W
TEMPERATURE (C)
40
SHORT-CIRCUIT CURRENT (mA)
35
20
I
SC
I
SC
+
LTC1350 TPC07
20
10
20
0
40
5
0
40
30
25
15
60
80
100
Driver Output Voltage
vs Temperature
Receiver Input Thresholds
vs Temperature
Driver Short-Circuit Current
vs Temperature
Driver Leakage in Shutdown
vs Temperature
V
CC
Supply Current
vs Temperature
Supply Current vs Data Rate
TEMPERATURE (C)
40
5
DRIVER OUTPUT VOLTAGE (V)
4
2
1
0
5
2
0
40
60
LTC1350 TPC01
3
3
4
1
20
20
80
100
V
CC
= 3.3V
OUTPUT HIGH
V
CC
= 3.3V
OUTPUT LOW
ALL DRIVERS WITH LOAD, R
L
= 3k
TEMPERATURE (C)
40
THRESHOLD VOLTAGE (V)
1.8
2.0
V
TH
+
V
TH
2.2
20
60
LT1350 TPC02
1.6
1.4
20
0
40
80
100
1.2
1.0
DATA RATE (k Baud)
0
SUPPLY CURRENT (mA)
20
25
30
60
100
LTC1350 TPC03
15
10
20
40
80
120
140
5
0
V
CC
= 3.3V
R
L
= 3k
C
L
= 2500pF
3 DRIVERS ACTIVE
TEMPERATURE (C)
40
0
SUPPLY CURRENT (mA)
0.5
1.5
2.0
2.5
5.0
3.5
0
40
60
LTC1350 TPC04
1.0
4.0
4.5
3.0
20
20
80
100
R
L
= 3k
3 DRIVERS LOADED
R
L
= 3k
1 DRIVER LOADED
TEMPERATURE (C)
0
LEAKAGE CURRENT (
A)
60
45
40
35
30
25
20
15
10
5
0
LTC1350 TPC05
20
70
10
30
40
50
V
OUT
= 20V
V
OUT
= 20V
TEMPERATURE (C)
40
SHORT-CIRCUIT CURRENT (mA)
14
20
I
SC
I
SC
+
LTC1350 TPC06
8
4
20
0
40
2
0
16
12
10
6
60
80
100
Receiver Short-Circuit Current
vs Temperature
DRIVER
OUTPUT
R
L
= 3k
C
L
= 1000pF
DRIVER
OUTPUT
R
L
= 3k
INPUT
LTC1350 TPC08
RECEIVER
OUTPUT
C
L
= 50pF
INPUT
LTC1350 TPC09
Driver Output Waveforms
Receiver Output Waveform
5
LTC1350
1350fa
U
U
U
PI FU CTIO S
SWITCHI G TI E WAVEFOR S
U
W
W
1.4V
0V
V
CC
0V
V
+
V
0V
DR
INPUT
DR
OUTPUT
1.4V
t
HLD
t
LHD
LTC1350 F01
0.8V
V
CC
0V
2.4V
RX
INPUT
RX
OUTPUT
1.3V
t
HLR
1.7V
t
LHR
LTC1350 F02
V
CC
0V
Figure 2. Receiver Propagation Delay Timing
Figure 1. Driver Propagation Delay Timing
C1
+
, C1
, C2
+
, C2
: Commutating Capacitor Inputs. These
pins require two external capacitors (C = 0.1F): one from
C1
+
to C1
and another from C2
+
to C2
. To maintain
charge pump efficiency, the capacitor's effective series
resistance should be less than 20.
DR IN: EIA/TIA-562 Driver Input Pins. Inputs are TTL/
CMOS compatible. Inputs should not be allowed to float.
Tie unused inputs to V
CC
.
DR OUT: Driver Outputs at EIA/TIA-562 Voltage Levels.
Outputs are in a high impedance state when in the Shutdown
mode or V
CC
= 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.
Receiver 1, 2 and 3 outputs are in a high impedance state
when in Shutdown mode to allow data line sharing.
Receivers 4 and 5 are kept alive in Shutdown.
V
CC
: 3.3V Input Supply Pin. Supply current is typically
35A in the Shutdown mode. This pin should be decoupled
with a 0.1F ceramic capacitor.
GND: Ground Pin.
ON/OFF: TTL/CMOS Compatible Shutdown Pin. A logic
low puts the device in the Shutdown mode with receivers
4 and 5 kept alive and the supply current equal to 35A. All
driver and other receiver outputs are in high impedance
state. This pin cannot float.
V
+
: Positive Supply Output. V
+
2V
CC
1V. This pin
requires an external capacitor (C = 0.1F) for charge
storage. The capacitor may be tied to ground or V
CC
. With
multiple devices, the V
+
and V
pins may be paralleled into
common capacitors. For a large number of devices,
increasing the size of the shared common storage
capacitors is recommended to reduce ripple.
V
: Negative Supply Output. V
(2V
CC
1.3V). This
pin requires an external capacitor (C = 0.1F) for charge
storage.
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