5 V Powered
CMOS RS-232 Drivers/Receivers
a
ADM223/ADM230L–ADM241L
ADM232L TYPICAL OPERATING CIRCUIT
FEATURES
Single 5 V Power Supply
5V INPUT
Meets All EIA-232-E and V.28 Specifications
120 kB/s Data Rate
On-Board DC-DC Converters
؎9 V Output Swing with 5 V Supply
Small 1 F Capacitors
Low Power Shutdown ≤1 A
Receivers Active in Shutdown (ADM223)
؎30 V Receiver Input Levels
Latch-Up FREE
Plug-In Upgrade for MAX223/230-241
Plug-In Upgrade for AD230–AD241
V
C1+
C1–
CC
+5V TO +10V
VOLTAGE
DOUBLER
1F
6.3V
1F
6.3V
1F
6.3V
V+
V–
C2+
C2–
+10V TO –10V
VOLTAGE
INVERTER
1F
16V
1F
16V
T1
T1
T1
T2
R1
R2
IN
OUT
TTL/CMOS
INPUTS*
RS-232
OUTPUTS
T2
T2
IN
OUT
R1
R1
OUT
IN
IN
TTL/CMOS
OUTPUTS
RS-232
INPUTS**
APPLICATIONS
Computers
Peripherals
Modems
R2
R2
OUT
GND
ADM232L
Printers
Instruments
* INTERNAL 400k⍀ PULL-UP RESISTOR ON EACH TTL/CMOS INPUT.
** INTERNAL 5k⍀ PULL-DOWN RESISTOR ON EACH RS-232 INPUT.
GENERAL DESCRIPTION
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 supplies. An internal
+12 V to –12 V charge pump voltage converter generates the
–12 V supply.
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.
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.
Table I. Selection Table
No. of
RS-232
Drivers
No. of
Low Power
Shutdown
(SD)
TTL
Part
Number
Power
Supply Voltage
RS-232
External
Three-State No. of
Receivers Capacitors
EN
Pins
ADM223
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
Yes (SD)
Yes
No
Yes (EN)
No
No
No
No
No
Yes
Yes
No
28
20
14
16
20
16
24
24
24
24
24
28
ADM230L 5 V
4
ADM231L 5 V and 7.5 V to 13.2 V
ADM232L 5 V
ADM233L 5 V
ADM234L 5 V
ADM235L 5 V
ADM236L 5 V
ADM237L 5 V
ADM238L 5 V
2
4
No
None
4
None
4
4
4
2
4
No
No
Yes
Yes
No
No
No
Yes
No
Yes
Yes
ADM239L 5 V and 7.5 V to 13.2 V
ADM241L 5 V
REV. A
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.
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Tel: 781/329-4700
Fax: 781/326-8703
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© Analog Devices, Inc., 2001