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Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, nor for any infringements of patents or other rights of third parties
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
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 T Y PICAL OPE RAT ING CIRCUIT
T able I. Selection T able
No. of
RS-232
Drivers
No. of
RS-232
Receivers
Low Power
Shutdown
(SD)
T T L
T hree-State
EN
Part
Number
Power
Supply Voltage
E xternal
Capacitors
No. of
Pins
ADM223
ADM230L
ADM231L
ADM232L
ADM233L
ADM234L
ADM235L
ADM236L
ADM237L
ADM238L
ADM239L
ADM241L
+5 V
+5 V
+5 V & +7.5 V to +13.2 V
+5 V
+5 V
+5 V
+5 V
+5 V
+5 V
+5 V
+5 V & +7.5 V to +13.2 V
+5 V
4
5
2
2
2
4
5
4
5
4
3
4
5
0
2
2
2
0
5
3
3
4
5
5
4
4
2
4
None
4
None
4
4
4
2
4
Yes (
SD
)
Yes
No
No
No
No
Yes
Yes
No
No
No
Yes
Yes (EN)
No
No
No
No
No
Yes
Yes
No
No
Yes
Yes
28
20
14
16
20
16
24
24
24
24
24
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
6
9 V Output Swing with +5 V Supply
Small 1
m
F Capacitors
Low Power Shutdown
≤
1
m
A
Receivers Active in Shutdown (ADM223)
ESD > 2 kV
6
30 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
GE NE RAL DE SCRIPT ION
T he 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. T he ADM223,
ADM230L, ADM235L, ADM236L and ADM241L feature a
low power shutdown mode that reduces power dissipation to
less than 5
μ
W, making them ideally suited for battery powered
equipment. T wo receivers remain enabled during shutdown on
the ADM223. T he 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.
T hese converters convert the +5 V input power to the
±
10 V
required for RS-232 output levels. T he 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.
T he ADM2xxL is an enhanced upgrade for the AD2xx family
featuring lower power consumption, faster slew rate and opera-
tion with smaller (1
μ
F) capacitors.
*INTERNAL 400k
PULL-UP RESISTOR ON EACH TTL/CMOS INPUT
**INTERNAL 5k
PULL-DOWN RESISTOR ON EACH RS-232 INPUT
+5V TO +10V
VOLTAGE
DOUBLER
+10V TO –10V
VOLTAGE
INVERTER
1
μ
F
16V
1
μ
F
6.3V
+5V INPUT
VCC
V+
V–
C1+
C1–
C2+
C2–
ADM232L
1
μ
F
6.3V
1
μ
F
16V
6
GND
15
4
5
3
1
2
1
μ
F
6.3V
T1IN
RS-232
OUTPUTS
TTL/CMOS
INPUTS*
T1OUT
T2IN
R1OUT
R2OUT
T2OUT
R1IN
R2IN
R1
R2
T2
T1
TTL/CMOS
OUTPUTS
RS-232
INPUTS**
13
10
7
11
8
14
9
12
16