MAX3221EEAE

Overview

The MAX3221EEAE is a single-driver, single-receiver RS-232 transceiver from Analog Devices/Maxim Integrated. It operates on a +3.0V to +5.5V supply and supports data rates up to 250kbps. The device features AutoShutdown technology, reducing supply current to 1µA when no valid signal is detected. It includes ±15kV ESD protection (Air-Gap), ±8kV Contact Discharge, and ±15kV Human Body Model ratings. The component is housed in a 16-pin SSOP package and functions within an operating temperature range of -40°C to +85°C.

Feature Summary

• AutoShutdown functionality reduces power consumption by disabling the charge pump and drivers upon detecting invalid RS-232 levels for 30µs.
• Integrated dual charge pumps generate internal +5.5V and -5.5V supplies using only four small capacitors.
• Enhanced electrostatic discharge protection ensures robustness against high-voltage static events without latchup.
• Proprietary low-dropout transmitter stage maintains true RS-232 output levels across the full voltage range.

Applications

• Notebook, subnotebook, and palmtop computers
• Battery-powered equipment and handheld devices
• Cellular phones and peripherals

Procurement Notes

Verify the specific suffix EEAE confirms the -40°C to +85°C industrial temperature rating and SSOP package. Confirm RoHS compliance status as indicated by the '+' designation. Check manufacturer documentation for discontinuation notices or lifecycle changes prior to finalizing procurement plans.

Selection Notes

Select this component for applications requiring minimal footprint and low standby power. Ensure external capacitors are rated for the required ripple current and temperature stability. Verify that the system logic levels match the TTL/CMOS inputs and outputs provided by the transceiver.

Part Context

This part belongs to the MAX3221E/MAX3223E/MAX3243E family of 3V-powered RS-232 interfaces. While the MAX3223E offers two drivers/receivers and the MAX3243E provides three drivers and five receivers, the MAX3221E is optimized for space-constrained designs requiring only a single channel.

Replacement Considerations

Direct pin-compatible alternatives within the same family include the MAX3223EEAE and MAX3243EEAE, which offer additional channels but maintain identical electrical characteristics and packaging.

FAQ

How does the AutoShutdown feature determine when to enter low-power mode?

The device enters shutdown mode if all receiver inputs remain between +0.3V and -0.3V for at least 30µs, indicating no valid RS-232 signal is present.

What is the purpose of the INVALID output pin?

The INVALID output goes low when no valid RS-232 signal levels are detected on any receiver input, serving as an indicator for the AutoShutdown logic or software control.

Can the MAX3221EEAE drive serial mice directly?

No, the MAX3221EEAE has only one driver. The MAX3243E variant is specifically designed with multiple drivers to meet the current and voltage requirements for driving serial mice.