REV. B

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 that

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

ADM232L TYPICAL OPERATING CIRCUIT

ADM232L

1 F

6.3V

1 F

16V

C1+

C1–

C2–

C2+

T1

T2

TTL/CMOS

INPUTS*

RS-232

OUTPUTS

R1

TTL/CMOS

OUTPUTS

RS-232

INPUTS**

R2

V–

1 F

16V

+10V TO –10V

VOLTAGE

INVERTER

1 F

6.3V

1 F

6.3V

5V INPUT

V+

+5V TO +10V

VOLTAGE

DOUBLER

GND

* INTERNAL 400k

PULL-UP RESISTOR ON EACH TTL/CMOS INPUT.

** INTERNAL 5k

PULL-DOWN RESISTOR ON EACH RS-232 INPUT.

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 and 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 and 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

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

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 supplies. An internal

+12 V to –12 V charge pump voltage converter 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.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.

Tel: 781/329-4700

www.analog.com

Fax: 781/326-8703

© Analog Devices, Inc., 2001

OBSOLETE