MAX3223ECUP+T

Overview

The MAX3223ECUP+T is a dual-driver, dual-receiver RS-232 transceiver from the MAX3221/MAX3223/MAX3243 family. It operates on a single +3.0V to +5.5V supply and features Maxim's AutoShutdown technology, reducing supply current to 1µA when no valid signal is detected. The device includes an integrated dual charge pump requiring only 0.1µF capacitors for 3.3V operation. It supports data rates up to 235kbps with guaranteed ±5.0V output swings at 120kbps. The component is housed in a 20-pin TSSOP package and is rated for an operating temperature range of -40°C to +85°C.

Feature Summary

• AutoShutdown functionality automatically disables the onboard power supply and drivers upon detecting invalid receiver input levels, significantly reducing power consumption during idle periods.
• Integrated dual charge-pump voltage converter generates required RS-232 voltages from a single low-voltage supply without external transformers or multi-supply requirements.
• High-efficiency design allows operation with small 0.1µF external capacitors when powered by 3.3V, simplifying board layout and component count.

Applications

• Battery-powered equipment requiring extended standby life
• Hand-held devices and portable diagnostics equipment
• Peripherals connecting microcontrollers to RS-232 interfaces

Procurement Notes

Verify the specific suffix 'CUP' against official manufacturer documentation to confirm the exact pinout, temperature grade, and RoHS compliance status. Ordering codes often contain subtle variations that affect physical dimensions or electrical ratings. Cross-reference the datasheet revision date to ensure compatibility with current design specifications before finalizing procurement.

Selection Notes

Select this component when designing systems that require low quiescent current during cable disconnection events. Ensure the application logic can tolerate the wake-up delay associated with the AutoShutdown feature. Verify that the load capacitance does not exceed limits that would degrade the slew rate or output voltage swing below RS-232 standards.

Part Context

This part belongs to the MAX3221/MAX3223/MAX3243 series of +3V to +5.5V RS-232 transceivers. The MAX3223 variant specifically provides two drivers and two receivers, distinguishing it from the single-channel MAX3221 and the five-receiver MAX3243. All members share the same core AutoShutdown architecture and charge-pump capabilities.

Replacement Considerations

MAX3223EAP+T: Alternative SSOP-20 package version within the same series.

FAQ

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

The device enters AutoShutdown mode if all receiver inputs remain between +0.3V and -0.3V for at least 30µs. It wakes up when any receiver input exceeds +2.7V or drops below -2.7V.

What is the maximum data rate supported by the MAX3223ECUP+T?

The device typically supports data rates up to 235kbps, while guaranteeing standard RS-232 performance at 120kbps under worst-case loading conditions.

Can the INVALID output be used for software-controlled shutdown?

Yes. By tying FORCEOFF and FORCEON together, the INVALID output can indicate DTR or Ring Indicator signals, allowing direct software control over the shutdown state.