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a
+5 V Powered
CMOS RS-232 Drivers/Receivers
ADM223/ADM230L–ADM241L
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 617/329-4700 World Wide Web Site: http://www.analog.com
Fax: 617/326-8703 © Analog Devices, Inc., 1997
ADM232L TYPICAL OPERATING CIRCUIT
Table I. Selection Table
No. of No. of Low Power TTL
Part Power RS-232 RS-232 External Shutdown Three-State No. of
Number Supply Voltage Drivers Receivers Capacitors (SD) EN Pins
ADM223 +5 V 4 5 4 Yes (SD) Yes (EN) 28
ADM230L +5 V 5 0 4 Yes No 20
ADM231L +5 V & +7.5 V to +13.2 V 2 2 2 No No 14
ADM232L +5 V 2 2 4 No No 16
ADM233L +5 V 2 2 None No No 20
ADM234L +5 V 4 0 4 No No 16
ADM235L +5 V 5 5 None Yes Yes 24
ADM236L +5 V 4 3 4 Yes Yes 24
ADM237L +5 V 5 3 4 No No 24
ADM238L +5 V 4 4 4 No No 24
ADM239L +5 V & +7.5 V to +13.2 V 3 5 2 No Yes 24
ADM241L +5 V 4 5 4 Yes Yes 28
FEATURES
Single 5 V Power Supply
Meets All EIA-232-E and V.28 Specifications
120 kB/s Data Rate
On-Board DC-DC Converters
69 V Output Swing with +5 V Supply
Small 1 mF Capacitors
Low Power Shutdown ≤1 mA
Receivers Active in Shutdown (ADM223)
ESD > 2 kV
630 V Receiver Input Levels
Latch-Up FREE
Plug-In Upgrade for MAX223/230-241
Plug-In Upgrade for AD230–AD241
APPLICATIONS
Computers
Peripherals
Modems
Printers
Instruments
GENERAL DESCRIPTION
The ADM2xx family of line drivers/receivers is intended for all
EIA-232-E and V.28 communications interfaces, especially in
applications where ±12 V is not available. The ADM223,
ADM230L, ADM235L, ADM236L and ADM241L feature a
low power shutdown mode that reduces power dissipation to
less than 5 µW, making them ideally suited for battery powered
equipment. Two receivers remain enabled during shutdown on
the ADM223. The ADM233L and ADM235L do not require
any external components and are particularly useful in applica-
tions where printed circuit board space is critical.
All members of the ADM230L family, except the ADM231L
and the ADM239L, include two internal charge pump voltage
converters that allow operation from a single +5 V supply.
These converters convert the +5 V input power to the ±10 V
required for RS-232 output levels. The ADM231L and
ADM239L are designed to operate from +5 V and +12 V sup-
plies. An internal +12 V to –12 V charge pump voltage con-
verter generates the –12 V supply.
The ADM2xxL is an enhanced upgrade for the AD2xx family
featuring lower power consumption, faster slew rate and opera-
tion with smaller (1 µF) capacitors.
*INTERNAL 400kW PULL-UP RESISTOR ON EACH TTL/CMOS INPUT
**INTERNAL 5kW PULL-DOWN RESISTOR ON EACH RS-232 INPUT
+5V TO +10V
VOLTAGE
DOUBLER
+10V TO –10V
VOLTAGE
INVERTER
1m F
16V
1m F
6.3V
+5V INPUT
V
CC
V+
V–
C1+
C1–
C2+
C2–
ADM232L
1m F
6.3V
1m F
16V
6
GND
15
4
5
3
1
2
1m F
6.3V
T1
IN
RS-232
OUTPUTS
TTL/CMOS
INPUTS*
T1
OUT
T2
IN
R1
OUT
R2
OUT
T2
OUT
R1
IN
R2
IN
R1
R2
T2
T1
TTL/CMOS
OUTPUTS
RS-232
INPUTS**
13
10 7
11
8
14
9
12
16