www.docs.chipfind.ru
1
LTC1350
3.3V Low Power
EIA/TIA-562 3-Driver/
5-Receiver Transceiver
S
FEATURE
D
U
ESCRIPTIO
s
Low Supply Current
300
A
s
Receivers 4 and 5 Kept Alive
in SHUTDOWN
35
A
s
ESD Protection
10kV
s
Operates from a Single 3.3V Supply
s
Uses Small Capacitors
0.1
F
s
Operates to 120k Baud
s
Three-State Outputs are High Impedance
When Off
s
Output Overvoltage Does Not Force Current
Back into Supplies
s
EIA/TIA-562 I/O Lines Can Be Forced to
25V
Without Damage
s
Flowthrough Architecture
The LTC1350 is a 3-driver/5-receiver EIA/TIA-562 trans-
ceiver with very low supply current. In the no load condi-
tion, the supply current is only 300
A. The charge pump
only requires four 0.1
F capacitors.
In SHUTDOWN mode, two receivers are kept alive and
the supply current is only 35
A. 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 120k baud 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.
U
S
A
O
PPLICATI
s
Notebook Computers
s
Palmtop Computers
U
A
O
PPLICATI
TYPICAL
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
2
LTC1350
A
U
G
W
A
W
U
W
A
R
BSOLUTE
XI
TI
S
W
U
U
PACKAGE/ORDER I FOR ATIO
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) ........................ 0
C to 70
C
Industrial (LTC1350I) ........................ 40
C to 85
C
Storage Temperature Range ................ 65
C to 150
C
Lead Temperature (Soldering, 10 sec)................. 300
C
ORDER PART
NUMBER
LTC1350CG
LTC1350CN
LTC1350CS
LTC1350IG
LTC1350IN
LTC1350IS
T
JMAX
= 125
C,
JA
= 96
C/W (G)
T
JMAX
= 125
C,
JA
= 56
C/W (N)
T
JMAX
= 125
C,
JA
= 85
C/W (S)
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
N PACKAGE
28-LEAD PLASTIC DIP
TOP VIEW
S PACKAGE
28-LEAD PLASTIC SOL
G PACKAGE
28-LEAD SSOP
Consult factory for Military grade parts
V
CC
= 3.3V, C1 = C2 = C3 = C4 = 0.1
F, unless otherwise noted.
ELECTRICAL C
C
HARA TERISTICS
C
D
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
Any Driver
Output Voltage Swing
3k to GND
Positive
q
3.7
4.5
V
Negative
q
3.7
4.5
V
Logic Input Voltage Level
Input Low Level (V
OUT
= High)
q
1.4
0.8
V
Input High Level (V
OUT
= Low)
q
2.0
1.4
V
Logic Input Current
V
IN
= V
CC
q
5
A
V
IN
= 0V
q
5
A
Output Short-Circuit Current
V
OUT
= 0V
10
mA
Output Leakage Current
SHUTDOWN (Note 3), V
OUT
=
20V
10
500
A
Any Receiver
Input Voltage Thresholds
Input Low Threshold
q
0.8
1.3
V
Input High Threshold
q
1.7
2.4
V
Hysteresis
q
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)
q
0.2
0.4
V
Output High, I
OUT
= 160
A (V
CC
= 3.3V)
q
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
q
1
10
A
3
LTC1350
V
CC
= 3.3V, C1 = C2 = C3 = C4 = 0.1
F, unless otherwise noted.
ELECTRICAL C
C
HARA TERISTICS
C
D
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) 0
C
T
A
70
C
q
0.3
0.6
mA
No Load (All Drivers V
IN
= 0)(Note 2) 0
C
T
A
70
C
q
0.5
1.0
mA
No Load (All Drivers V
IN
= V
CC
)(Note 2) 40
C
T
A
85
C
q
0.3
1.0
mA
No Load (All Drivers V
IN
= 0)(Note 2) 40
C
T
A
85
C
q
0.5
1.5
mA
SHUTDOWN (Note 3)
q
35
50
A
ON/OFF Threshold Low
q
1.4
0.8
V
ON/OFF Threshold High
q
2.0
1.4
V
The
q
denotes specifications which apply over the operating temperature
range of 0
C
T
A
70
C for commercial grade, 40
C
T
A
85
C for
Industrial grade.
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.
Note 3: Supply current measurement in SHUTDOWN mode is performed
with V
ON/OFF
= 0V.
C
C
HARA TERISTICS
AC
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)
q
2
3.5
s
(TTL to EIA/TIA-562)
t
LHD
(Figure 1)
q
2
3.5
s
Receiver Propagation Delay
t
HLR
(Figure 2)
q
0.3
0.8
s
(EIA/TIA-562 to TTL)
t
LHR
(Figure 2)
q
0.3
0.8
s
V
CC
= 5V, C1 = C2 = C3 = C4 = 0.1
F, unless otherwise noted.
4
LTC1350
TYPICAL PERFOR A CE CHARACTERISTICS
W U
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
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
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
PI FU CTIO S
U
U
U
V
CC
: 3.3V Input Supply Pin. Supply current is typically
35
A in the SHUTDOWN mode. This pin should be de-
coupled with a 0.1
F ceramic capacitor.
GND: Ground Pin.
ON/OFF: TTL/CMOS Compatible Shutdown Pin. A logic
low puts the device in the SHUTDOWN mode with receiv-
ers 4 and 5 kept alive and the supply current equal to 35
A.
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 = 0.1
F) 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, in-
creasing the size of the shared common storage capaci-
tors is recommended to reduce ripple.
V
: Negative Supply Output. V
(2V
CC
1.3V). This
pin requires an external capacitor (C = 0.1
F) for charge
storage.
SWITCHI G TI E WAVEFOR S
W
W
U
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 = 0.1
F): 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 SHUT-
DOWN 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 Lev-
els. 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.
PDF 
ZIP