General Description

The MAX3228/MAX3229 are +2.5V to +5.5V powered

EIA/TIA-232 and V.28/V.24 communications interfaces

with low power requirements, and high data-rate capa-

bilities, in a chip-scale package (UCSP™).

The MAX3228/MAX3229 achieve a 1µA supply current

with Maxim’s AutoShutdown™ feature. They save

power without changes to existing BIOS or operating

systems by entering low-power shutdown mode when

the RS-232 cable is disconnected, or when the trans-

mitters of the connected peripherals are off.

The transceivers have a proprietary low-dropout trans-

mitter output stage, delivering RS-232 compliant perfor-

mance from a +3.1V to +5.5V supply, and RS-232

compatible performance with a supply voltage as low

as +2.5V. The dual charge pump requires only four

small 0.1µF capacitors for operation from a +3.0V sup-

ply. Each device is guaranteed to run at data rates of

250kbps while maintaining RS-232 output levels.

The MAX3228/MAX3229 offer a separate power-supply

input for the logic interface, allowing configurable logic

levels on the receiver outputs and transmitter inputs.

MAX3228/MAX3229 compatibility with multiple logic

families.

The MAX3229 contains one receiver and one transmit-

ter. The MAX3228 contains two receivers and two

transmitters. The MAX3228/MAX3229 are available in

tiny chip-scale packaging and are specified across the

extended industrial temperature range of -40°C to

+85°C.

Applications

Personal Digital Assistants

Cell Phone Data Lump Cables

Set-Top Boxes

Hand-Held Devices

Cell Phones

Features

o 1µA Low-Power AutoShutdown

o 250kbps Guaranteed Data Rate

o Meets EIA/TIA-232 Specifications Down to +3.1V

o RS-232 Compatible to +2.5V Allows Operation

from Single Li+ Cell

o Small 0.1µF Capacitors

o Configurable Logic Levels

+2.5V to +5.5V RS-232 Transceivers

in UCSP

________________________________________________________________ Maxim Integrated Products

1

MAX3228

5k

Ω

T2OUT

T2IN

TTL/CMOS

INPUTS

C2-

C2+

C1-

C1+

A1

A5

C1

D1

A2

A3

A6

B6

B1

A4

E3

E4

E2

20

µA

20

µA

E1

C5

B5

V-

V+

2.5V TO 5.5V

C4

0.1

µF

C3

0.1

µF

C1

0.1

µF

C2

0.1

µF

0.1

µF

FORCEOFF

FORCEON

INVALID

T1OUT

T1IN

GND

TO POWER-

MANAGEMENT

UNIT

RS-232

OUTPUTS

1.65V TO 5.5V

5k

Ω

R2IN

R2OUT

TTL/CMOS

OUTPUTS

D6

C6

E6

E5

R1IN

R1OUT

RS-232

INPUTS

0.1

µF

Typical Operating Circuits

19-2140; Rev 0; 8/01

For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at

1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

*Requires solder temperature profile described in the Absolute

Maximum Ratings section.

*UCSP reliability is integrally linked to the user’s assembly

methods, circuit board material, and environment. Refer to the

UCSP Reliabilitly Notice in the UCSP Reliability section of this

data sheet for more information.

Ordering Information

PART

TEMP. RANGE

PIN-

PACKAGE

MAX3228EBV

-40

°C to +85°C6 ✕ 5 UCSP*

MAX3229EBV

-40

°C to +85°C6 ✕ 5 UCSP*

UCSP is a trademark of Maxim Integrated Products, Inc.

AutoShutdown is a trademark of Maxim Integrated Products, Inc.

Typical Operating Circuits continued at end of data sheet.

Pin Configurations appear at end of data sheet.