MAX3221ECUE+

Overview

The MAX3221ECUE+ is a single-driver, single-receiver RS-232 transceiver manufactured by Analog Devices Inc./Maxim Integrated. It operates on a +3.0V to +5.5V supply and supports data rates up to 250kbps. The device features an AutoShutdown function that reduces supply current to 1µA when no valid signal is detected. It includes ±15kV ESD protection via IEC Air-Gap Discharge and ±8kV Contact Discharge. The component is housed in a 16-pin TSSOP package and functions within a commercial temperature range of 0°C to +70°C.

Feature Summary

• AutoShutdown technology enables ultra-low power consumption by automatically disabling the charge pump and drivers when the RS-232 cable is disconnected or peripheral transmitters are off.
• Integrated dual charge pumps generate true RS-232 voltage levels from low-voltage supplies using only four small capacitors.
• Robust electrostatic discharge protection ensures reliability against high-voltage static events without latchup.

Applications

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

Procurement Notes

Verify the specific suffix 'ECUE+' to confirm the 16-pin TSSOP package and the 0°C to +70°C commercial operating temperature range. Ensure compatibility with existing BIOS or operating systems as the AutoShutdown feature requires no software modifications for power management.

Selection Notes

Select this part for space-constrained designs requiring a single-channel interface. Verify that the application environment remains within the 0°C to +70°C limit; otherwise, consider the EE variant for extended industrial temperatures. Confirm that the 250kbps maximum data rate meets the system's communication requirements.

Part Context

This component belongs to the MAX3221E/MAX3223E/MAX3243E family of 3V-powered RS-232 transceivers. While the MAX3223E offers two channels and the MAX3243E provides three drivers and five receivers, the MAX3221E is optimized for minimal footprint applications requiring only one transmitter and one receiver path.

Replacement Considerations

Public confirmed substitutes include MAX3221EEAE+ (Extended Temperature) and MAX3221ECTE+ (TQFN Package).

FAQ

How does the AutoShutdown feature reduce power consumption?

When FORCEON is low and FORCEOFF is high, the device monitors receiver inputs. If no valid RS-232 signal levels are detected for 30µs, the internal charge pump and drivers shut off, reducing supply current to 1µA.

What ESD protection standards does the MAX3221ECUE+ meet?

The device withstands ±15kV IEC 1000-4-2 Air-Gap Discharge, ±8kV IEC 1000-4-2 Contact Discharge, and ±15kV Human Body Model discharges.

Can the MAX3221ECUE+ operate directly from a 3.3V supply?

Yes, the device operates from a +3.0V to +5.5V supply. For 3.3V operation, it requires four 0.1µF capacitors for the charge pump circuit.