LTC1349 Datasheet, PDF (1/8 Pages) Linear Technology – 5V Low Power RS232 3-Driver/5-Receiver Transceiver with 2 Receivers Active in SHUTDOWN

LTC1349
5V Low Power RS232
3-Driver/5-Receiver Transceiver
with 2 Receivers Active
in SHUTDOWN
FEATURES
s _{Low Supply Current: 300µA}
s _{Two Receivers Kept Alive in SHUTDOWN}
s _{ESD Protection Over ±10kV}
s _{Operates from a Single 5V Supply}
s _{Uses Small Capacitors: 0.1µF}
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 _{RS232 I/O Lines Can Be Forced to ±25V}
Without Damage
s _{Pin Compatible with LT1137A and LT1237}
s _{Flowthrough Architecture}
APPLICATI S
s _{Notebook Computers}
s _{Palmtop Computers}
DESCRIPTIO
The LTC1349 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.
In SHUTDOWN mode, two receivers are kept alive and the
supply current is 35µA. All RS232 outputs assume a high
impedance state in SHUTDOWN and with the power off.
The LTC1349 is fully compliant with all data rate and
overvoltage RS232 specifications. The transceiver can
operate up to 120k baud 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.
TYPICAL APPLICATI
C1
0.1µF
3-Drivers/5-Receivers with SHUTDOWN
V⁺ 1
V_CC ²
3
C2
0.1µF
4
DRIVER 1 OUT ⁵
RX1 IN ⁶
DRIVER 2 OUT ⁷
RX2 IN ⁸
RX3 IN ⁹
10
RX4 IN
11
DRIVER 3 OUT
12
RX5 IN
13
ON/OFF
14
NC
LTC1349
28 V^–
27
26
C3
0.1µF
25
DRIVER 1 IN
24
RX1 OUT
23
DRIVER 2 IN
22
RX2 OUT
21
RX3 OUT
20
RX4 OUT
19
DRIVER 3 IN
18
RX5 OUT
17
GND
16
NC
15
NC
C4
0.1µF
LTC1349 • TA01
Quiescent and SHUTDOWN Supply Current
vs Temperature
1200
60
1000
50
SHUTDOWN
800
CURRENT
40
600
30
400
QUIESCENT
CURRENT
20
200
10
0
0
–40 –20 0 20 40 60 80 100
TEMPERATURE (°C)
TEST CONDITION:
V_CC = 5V, ALL DRIVER INPUTS TIED TO V_CC.
LTC1349 • TA02
1