LT1140A_15 Datasheet, PDF (1/12 Pages) Linear Technology – Advanced Low Power 5V RS232 Drivers/Receivers with Small Capacitors

LT1130A/LT1140A Series
Advanced Low Power
5V RS232 Drivers/Receivers
with Small Capacitors
FEATURES
s _{ESD Protection over ±10kV}
(±15kV IEC-1000-4-2 for LT1133A, LT1137A
and LT1141A)
s _{Uses Small Capacitors: 0.1µF, 0.2µF}
s _{1µA Supply Current in SHUTDOWN}
s _{120kBaud Operation for RL = 3k, CL = 2500pF}
s _{250kBaud Operation for RL = 3k, CL = 1000pF}
s _{CMOS Comparable Low Power}
s _{Easy PC Layout: Flowthrough Architecture}
s _{Rugged Bipolar Design: Absolutely No Latchup}
s _{Outputs Assume a High Impedance State When Off}
or Powered Down
s _{Improved Protection: RS232 I/O Lines Can Be Forced}
to ±30V Without Damage
s _{Output Overvoltage Does Not Force Current Back}
into Supplies
s _{Available in SO and SSOP Packages}
DESCRIPTIO
The LT^®1130A/LT1140A series of RS232 drivers/receiv-
ers features special bipolar construction techniques which
protect the drivers and receivers beyond the fault condi-
tions stipulated for RS232. Driver outputs and receiver
inputs can be shorted to ±30V without damaging the
device or the power supply generator. In addition, the
RS232 I/O pins are resilient to multiple ±10kV ESD strikes.
An advanced driver output stage operates up to 250kbaud
while driving heavy capacitive loads. Supply current is
typically 12mA, competitive with CMOS devices.
Several members of the series include flexible operating
mode controls. The DRIVER DISABLE pin disables the
drivers and the charge pump, the ON/OFF pin shuts down
all circuitry. While shut down, the drivers and receivers
assume high impedance output states.
, LTC and LT are registered trademarks of Linear Technology Corporation.
TYPICAL APPLICATIO
Basic Operation
V⁺ 1
0.1µF
5V V_CC
2
3
0.1µF
4
×2
DRIVER OUT
5
RX IN ⁶
DRIVER OUT ⁷
8
RX IN
TO LINE
RX IN ⁹
RX IN ¹⁰
DRIVER OUT ¹¹
RX IN ¹²
ON/OFF = 5V ¹³
14
LT1137A
28 V ^–
27
0.1µF
0.1µF
26
×2
25 _{DRIVER IN}
24 _{RX OUT}
23 _{DRIVER IN}
22
RX OUT
21 _{RX OUT}
TO LOGIC
20
RX OUT
19 _{DRIVER IN}
18 _{RX OUT}
17
GND
16
DRIVER DISABLE
15
1130A • TA01
LT1130A 5-Driver/5-Receiver RS232 Transceiver
LT1131A 5-Driver/4-Receiver RS232 Transceiver w/Shutdown
LT1132A 5-Driver/3-Receiver RS232 Transceiver
LT1133A 3-Driver/5-Receiver RS232 Transceiver
LT1134A 4-Driver/4-Receiver RS232 Transceiver
LT1135A 5-Driver/3-Receiver RS232 Transceiver w/o Charge Pump
RECEIVER
OUTPUT
C_L = 50pF
DRIVER
ROUTPUT
R_L = 3k
C_L = 2500pF
Output Waveforms
INPUT
LT1130A • TA02
LT1136A 4-Driver/5-Receiver RS232 Transceiver w/Shutdown
LT1137A 3-Driver/5-Receiver RS232 Transceiver w/Shutdown
LT1138A 5-Driver/3-Receiver RS232 Transceiver w/Shutdown
LT1139A 4-Driver/4-Receiver RS232 Transceiver w/Shutdown
LT1140A 5-Driver/3-Receiver RS232 Transceiver w/o Charge Pump
LT1141A 3-Driver/5-Receiver RS232 Transceiver w/o Charge Pump
1