MAX3223EEUP+

Overview

The MAX3223EEUP+ is a dual-driver, dual-receiver RS-232 transceiver manufactured by Analog Devices Inc./Maxim Integrated. It operates on a single +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 on all I/O pins and utilizes a dual charge pump requiring four 0.1µF capacitors. The component is housed in a 20-pin TSSOP package and functions within a temperature range of -40°C to +85°C.

Feature Summary

• AutoShutdown technology automatically disables the charge pump and drivers to achieve ultra-low 1µA standby current when the cable is disconnected or peripherals are off.
• Integrated dual charge pumps generate true RS-232 voltage levels from low-voltage supplies using only four small external capacitors.
• Enhanced electrostatic discharge protection ensures robustness against ±15kV air-gap, ±8kV contact discharge, and ±15kV human body model events.

Applications

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

Procurement Notes

Verify the specific suffix EEUP+ corresponds to the required 20-pin TSSOP package and industrial temperature range (-40°C to +85°C). Confirm lead-free/RoHS compliance status with the supplier. Ensure the ordering quantity matches distributor minimums and check for any regional distribution restrictions before finalizing procurement.

Selection Notes

Select this part for applications requiring full-duplex communication with two independent channels. It is suitable for space-constrained designs due to the compact TSSOP footprint. Verify that the system power supply remains within the +3.0V to +5.5V range and that external 0.1µF capacitors can be placed close to the device for optimal charge pump performance.

Part Context

This component belongs to the MAX3221E/MAX3223E/MAX3243E family of 3V-powered RS-232 transceivers. While the MAX3221E offers one driver/receiver and the MAX3243E provides three drivers and five receivers, the MAX3223E specifically delivers two drivers and two receivers. All variants share the same core AutoShutdown and ESD protection technologies.

Replacement Considerations

Publicly confirmed substitutes include the MAX3223ECAP+ (20-SSOP) and MAX3223ECTP+ (20-TQFN-EP), which offer identical electrical specifications but differ in physical package dimensions.

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 until a valid signal reactivates the device.

What is the purpose of the INVALID output pin?

The INVALID output goes low when no valid RS-232 signal levels are present on any receiver input. It serves as an indicator for the absence of a connection or active peripheral and is functional in all operating modes.

Can the MAX3223EEUP+ drive serial mice directly?

No, the MAX3223E lacks the specific 'AutoShutdown Plus' feature required for mouse driveability. The MAX3243E is designed for this application; if using the MAX3223E, FORCEOFF and FORCEON must be tied to VCC to prevent automatic shutdown during mouse operation.