MAX3244ECAI+T

Overview

The MAX3244ECAI+T is a single-supply RS-232 transceiver manufactured by Analog Devices/Maxim Integrated. It operates from a +3.0V to +5.5V supply and features AutoShutdown Plus technology, achieving a typical 1µA supply current when inactive. The device includes three drivers and five receivers with full-duplex communication capability. It guarantees a maximum data rate of 250kbps and utilizes a dual charge pump requiring only four small capacitors for voltage conversion. The component provides ±5V transmitter output swings and incorporates an INVALID signal detector.

Feature Summary

• AutoShutdown Plus functionality automatically reduces power consumption by disabling the charge pump and transmitters during periods of inactivity or cable disconnection.
• Integrated INVALID output signal detects valid RS-232 receiver levels independently of shutdown states.
• Proprietary low-dropout transmitter stage ensures true RS-232 performance across the specified voltage range.
• R2OUTB pin provides an always-active noninverting receiver output for monitoring peripheral activity.

Applications

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

Procurement Notes

Verify the specific ordering suffix against official documentation to confirm package type and temperature range. Confirm RoHS compliance status directly with the manufacturer's datasheet. Ensure the SSOP-28 package variant matches the design requirements. Cross-reference the part number with authorized distributors to validate authenticity and availability.

Selection Notes

Select this component for applications requiring low-power standby modes without BIOS modifications. Choose the MAX3244 over the MAX3245 if a guaranteed 250kbps data rate is sufficient. Consider the R2OUTB feature for ring indicator monitoring in systems where VCC is grounded during shutdown. Verify capacitor values match the operating supply voltage for optimal charge pump performance.

Part Context

This device belongs to the MAX3224–MAX3227/MAX3244/MAX3245 family of 3V-powered EIA/TIA-232 interfaces. It shares core architecture with the MAX3224 and MAX3226 but offers additional receiver outputs. The family is characterized by its AutoShutdown Plus feature and compatibility with standard RS-232 protocols.

Replacement Considerations

Public confirmed substitute part numbers are not available in the provided source material.

FAQ

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

The device enters shutdown mode when the RS-232 cable is disconnected, connected peripheral transmitters are inactive, and the UART driving the transmitter inputs has been inactive for more than 30 seconds.

What is the function of the R2OUTB pin on the MAX3244?

R2OUTB is an always-active, noninverting complementary receiver output that allows monitoring of receiver activity while other receivers are in a high-impedance state during shutdown.

Does the INVALID output depend on the FORCEON or FORCEOFF control states?

No, the INVALID output indicates the receiver input condition and is independent of the FORCEON and FORCEOFF states.