LT1381_15 Datasheet, PDF (1/8 Pages) Linear Technology – Low Power 5V RS232 Dual Driver/Receiver with 0.1F Capacitors

FEATURES
s _{ESD Protection over ±10kV}
s _{Low Cost}
s _{Uses Small Capacitors: 0.1µF}
s _{CMOS Comparable Low Power: 40mW}
s _{Operates from a Single 5V Supply}
s _{120kBaud Operation for RL = 3k, CL = 2500pF}
s _{250kBaud Operation for RL = 3k, CL = 1000pF}
s _{Rugged Bipolar Design}
s _{Outputs Assume a High Impedance State When}
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s _{Absolutely No Latchup}
s _{Available in Narrow SO Package}
APPLICATI S
s _{Portable Computers}
s _{Battery-Powered Systems}
s _{Power Supply Generator}
s _Terminals
s _Modems
TYPICAL APPLICATI
1
+
0.1µF
3
4
+
0.1µF
5
11
LOGIC
INPUTS
10
12
LOGIC
OUTPUTS
9
LT1381
16
5V INPUT
2
+
V⁺ OUT
0.1µF
6
V ^– OUT
+ ^0.1µF
14
RS232 OUTPUT
7
13
5k
8
S
5k ₁₅
RS232 OUTPUT
RS232 INPUT
RS232 INPUT
LT1381 • TA01
LT1381
Low Power 5V RS232 Dual
Driver/Receiver with
0.1µF Capacitors
DESCRIPTIO
The LT^®1381 is a dual RS232 driver/receiver pair with
integral charge pump to generate RS232 voltage levels
from a single 5V supply. The circuit features rugged
bipolar design to provide operating fault tolerance and
ESD protection unmatched by competing CMOS designs.
Using only 0.1µF external capacitors, the circuit con-
sumes only 40mW of power and can operate to 120kbaud
even while driving heavy capacitive loads. New ESD struc-
tures on the chip allow the LT1381 to survive multiple
±10kV strikes, eliminating the need for costly TransZorbs^®
on the RS232 line pins. Driver outputs are protected from
overload and can be shorted to ground or up to ±25V
without damage. During power-off conditions, driver and
receiver outputs are in a high impedance state, allowing
line sharing.
, LTC and LT are registered trademarks of Linear Technology Corporation.
TransZorb^® is a registered trademark of General Instruments, GSI
DRIVER
OUTPUT
R_L = 3k
C_L = 2500pF
RECEIVER
ROUTPUT
C_L = 50pF
INPUT
Output Waveforms
LT1381 • TA02
1