MAX221ECAE+

Overview

The MAX221ECAE+ is a single RS-232 transceiver powered by a +5V supply, featuring AutoShutdown and high data rate capabilities. It operates within a commercial temperature range of 0°C to +70°C in a 16-pin SSOP package. The device guarantees a maximum data rate of 250kbps with worst-case loads of 3kΩ in parallel with 1000pF. Supply current is reduced to 1µA during shutdown when no valid signal is detected for 30µs. ESD protection on the transmitter output and receiver input withstands ±15kV (Human Body Model), ±8kV (IEC Contact Discharge), and ±15kV (IEC Air-Gap).

Feature Summary

• AutoShutdown feature reduces supply current to 1µA when no valid RS-232 signal is present.
• Enhanced ESD protection on RS-232 I/O pins meets IEC 1000-4-2 Level 4 standards.
• Integrated dual charge pumps generate required voltage levels from a single +5V supply.
• Latchup-free design ensures reliable operation under static discharge conditions.

Applications

• Maintenance and diagnostic ports
• Industrial systems
• Telecommunications equipment
• Set-top boxes

Procurement Notes

Verify the ordering suffix 'AE' confirms the commercial temperature range (0°C to +70°C) and SSOP package type. Confirm RoHS compliance status through official manufacturer documentation or distributor certificates before finalizing procurement specifications.

Selection Notes

Select this component for applications requiring low power consumption without BIOS modifications. Ensure the system operates within the specified +4.5V to +5.5V supply range. Verify that the 250kbps data rate meets communication requirements and that the 16-pin SSOP footprint fits the board layout constraints.

Part Context

The MAX221E belongs to Maxim Integrated's family of single RS-232 transceivers designed for low-power serial communications. The 'CAE' designation indicates the specific temperature grade and package variant. This series emphasizes power savings through automatic shutdown mechanisms while maintaining robust interface protection.

Replacement Considerations

Cross-reference with other MAX221 variants such as MAX221EEAE+ for extended temperature ranges (-40°C to +85°C). Verify pin compatibility and electrical characteristics against alternative single-channel RS-232 transceivers if sourcing changes occur.

FAQ

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

The device enters shutdown mode when it senses no valid RS-232 signal levels on the receiver input for at least 30µs, reducing supply current to 1µA.

What is the function of the INVALID output pin?

The INVALID output is pulled low when no valid RS-232 level is detected on the receiver input, indicating that the port is inactive or disconnected.

Can the MAX221E operate without external capacitors?

No, the internal dual charge pumps require four external 0.1µF capacitors (C1-C4) to generate the positive and negative voltage supplies from the +5V source.