1 Features

• ESD protection for RS-232 pins

– ±15kV Human-body model (HBM)

– ±8kV (IEC 61000-4-2, Contact discharge)

– ±15kV (IEC 61000-4-2, Air-gap discharge)

• Meets or exceeds the requirements of TIA/

EIA-232-F and ITU v.28 standards

• Operates with 3V to 5.5V VCC supply

• Operates up to 250kbit/s

• One driver and one receiver

• Low standby current: 1μA typical

• Accepts 5V logic input with 3.3V supply

• Auto-power-down feature automatically disables

drivers for power savings

• Alternative high-speed device (1Mbit/s)

– SN75C3221E and SN65C3221E

2 Applications

• Industrial PCs

• Wired networking

• Data center and enterprise computing

• Battery-powered systems

• PDAs

• Notebooks

• Laptops

• Palmtop PCs

• Hand-held equipment

3 Description

The MAX3221E is a single driver, single receiver

RS-232 solution operating from a single VCC supply.

The RS-232 pins provide IEC 61000-4-2 ESD

protection. The device meets the requirements of

TIA/EIA-232-F and provides the electrical interface

between an asynchronous communication controller

and the serial-port connector. The charge pump and

four small external capacitors allow operation from a

single 3V to 5.5V supply. These devices operate at

data signaling rates up to 250kbit/s and a maximum of

30V/μs driver output slew rate.

Flexible control options for power management are

available. Auto-power down disables driver and

charge pump when the receiver is disconnected or

the remote driver is power down. The drivers can be

manually enabled or disabled. INVALID output goes

low when receiver input is unconnected or power off.