LTC1347
5V Low Power RS232
3-Driver/5-Receiver Transceiver
with 5 Receivers Active
in Shutdown
FEATURES
s
s
s
s
s
s
s
s
DESCRIPTIO
s
s
s
Low Supply Current: 300碌A
Five Receivers Kept Alive in Shutdown
ESD Protection Over
鹵10kV
Operates from a Single 5V Supply
Uses Small Capacitors: 0.1碌F
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
鹵25V
Without Damage
Pin Compatible with LT1137 and LT1237
Flowthrough Architecture
The LTC1347 is a 3-driver/5-receiver RS232 transceiver
with very low supply current. In the no load condition, the
supply current is only 300碌A. The charge pump only
requires four 0.1碌F capacitors.
In Shutdown mode, all five receivers are kept alive and the
supply current is 80碌A. 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, 3k鈩?load. Both
driver outputs and receiver inputs can be forced to
鹵25V
without damage, and can survive multiple
鹵10kV
ESD
strikes.
APPLICATI
s
s
S
Notebook Computers
Palmtop Computers
TYPICAL APPLICATI
3-Drivers/5-Receivers with SHUTDOWN
V
+
C1
0.1碌F
C2
0.1碌F
DRIVER 1 OUT
RX1 IN
DRIVER 2 OUT
RX2 IN
RX3 IN
RX4 IN
DRIVER 3 OUT
RX5 IN
ON/OFF
NC
V
CC
1
2
3
4
5
6
7
8
9
10
11
12
13
14
LTC1347
28
27
26
25
24
23
22
21
20
19
18
17
16
15
C3
0.1碌F
DRIVER 1 IN
RX1 OUT
DRIVER 2 IN
RX2 OUT
RX3 OUT
RX4 OUT
DRIVER 3 IN
RX5 OUT
GND
NC
NC
1347 TA01
Quiescent and Shutdown Supply Current vs
Temperature
1200
120
100
SHUTDOWN CURRENT (碌A)
V
鈥?/div>
C4
0.1碌F
1000
QUIESCENT CURRENT (碌A)
800
600
400
200
0
鈥?0
0
0
80 100
20
60
40
TEMPERATURE (擄C)
TEST CONDITION:
V
CC
= 5V, ALL DRIVER INPUTS TIED TO V
CC
.
鈥?0
1347 TA02
U
SHUTDOWN
CURRENT
80
60
QUIESCENT
CURRENT
40
20
UO
UO
1
1
2
3
4
5
6
7
8
