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.

a

ADM202/ADM203

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

Tel: 781/329-4700

World Wide Web Site: http://www.analog.com

Fax: 781/326-8703

© Analog Devices, Inc., 2001

FUNCTIONAL BLOCK DIAGRAMS

ADM202

0.1 F

6.3V

0.1 F

16V

C1+

C1–

C2–

C2+

T1

T2

TTL/CMOS

INPUTS*

RS-232

OUTPUTS

R1

TTL/CMOS

OUTPUTS

RS-232

INPUTS**

R2

V–

0.1 F

16V

+10V TO –10V

VOLTAGE

INVERTER

0.1 F

6.3V

0.1 F

6.3V

5V INPUT

V+

+5V TO +10V

VOLTAGE

DOUBLER

GND

T1

T2

TTL/CMOS

INPUTS*

RS-232

OUTPUTS

R1

TTL/CMOS

OUTPUTS

RS-232

INPUTS**

R2

5V INPUT

DO NOT MAKE

CONNECTIONS

TO THESE PINS

C1+

C1–

INTERNAL

–10V POWER

SUPPLY

V–

V–

V+

INTERNAL

+10V POWER

SUPPLY

C2+

C2+

C2–

C2–

GND

GND

ADM203

*INTERNAL 400k

PULL-UP RESISTOR ON EACH TTL/CMOS INPUT.

**INTERNAL 5k

PULL-DOWN RESISTOR ON EACH RS-232 INPUT.

*INTERNAL 400k

PULL-UP RESISTOR ON EACH TTL/CMOS INPUT.

**INTERNAL 5k

PULL-DOWN RESISTOR ON EACH RS-232 INPUT.

GENERAL DESCRIPTION

The ADM202/ADM203 is a two-channel RS-232 line driver/

receiver pair designed to operate from a single 5 V power sup-

ply. A highly efficient on-chip charge pump design permits

RS-232 levels to be developed using charge pump capacitors as

small as 0.1

µF. The capacitors are internal to the package on

the ADM203 so no external capacitors are required. These

converters generate

±10 V RS-232 output levels.

The ADM202/ADM203 meets or exceeds the EIA-232-E and

V.28 specifications. Fast driver slew rates permit operation up to

120 kB while high-drive currents allow for extended cable lengths.

An epitaxial BiCMOS construction minimizes power consump-

tion to 10 mW and also guards against latch-up. Overvoltage

protection is provided allowing the receiver inputs to withstand

continuous voltages in excess of

± 30 V. In addition, all pins

contain ESD protection to levels greater than 2 kV.

The ADM202 is available in 16-lead DIP and both narrow and

wide SOIC packages. The ADM203 is available in a 20-lead

DIP package.

FEATURES

120 kB Transmission Rate

ADM202: Small (0.1

F) Charge Pump Capacitors

ADM203: No External Capacitors Required

Single 5 V Power Supply

Meets EIA-232-E and V.28 Specifications

Two Drivers and Two Receivers

On-Board DC-DC Converters

9 V Output Swing with 5 V Supply

30 V Receiver Input Levels

APPLICATIONS

Computers

Peripherals

Modems

Printers

Instruments

High-Speed, 5 V, 0.1 F

CMOS RS-232 Driver/Receivers