MAX3237EEAI

Overview

The MAX3237EEAI+ is a true RS-232 transceiver manufactured by Analog Devices (Maxim Integrated) in an SSOP-28 package. It operates on a single +3.0V to +5.5V supply and features five drivers and three receivers for full-duplex communication. The device supports data rates up to 250kbps in standard mode and up to 1Mbps in MegaBaud mode. Operating supply current is typically 2mA, dropping to 10nA in shutdown mode when inputs are invalid. It includes ±15kV ESD protection on all pins, internal charge pumps requiring four 0.1μF capacitors, and a propagation delay of 0.15μs.

Feature Summary

• Integrated dual charge pump generates ±5.5V from a single low-voltage supply using only four small external capacitors.
• Enhanced electrostatic discharge protection rated at ±15kV across all logic and RS-232 I/O pins.
• MegaBaud operating mode enables transmission speeds up to 1Mbps with minimal load capacitance.
• Ultra-low power shutdown mode reduces supply current to 10nA while keeping receiver outputs active for system monitoring.

Applications

• Battery-powered portable equipment
• Cell phone and smartphone data cables
• Notebook and subnotebook computers

Procurement Notes

Verify the specific suffix EEAI against official manufacturer documentation to confirm the extended temperature range (-40°C to +85°C) and SSOP-28 packaging. Ensure that ordering codes match the exact lead-free and RoHS-compliant specifications required for your assembly process.

Selection Notes

Select this component when designing systems requiring high pin counts for peripheral interfaces, as it provides five drivers and three receivers. Consider the MegaBaud feature if higher throughput is needed without increasing voltage levels. Verify that the external capacitor footprint can accommodate the required 0.1μF components for the internal charge pumps.

Part Context

This part belongs to the MAX3222E/MAX3232E/MAX3237E/MAX3241E/MAX3246E family of low-power RS-232 transceivers. While sharing core architecture with other members like the MAX3232E, the MAX3237E is specifically optimized for applications needing multiple transmitter channels, such as complex peripheral connections in mobile devices.

Replacement Considerations

Public confirmed substitute part numbers: MAX3237EAI+, MAX3237ECPWR.

FAQ

How does the MAX3237EEAI+ achieve ultra-low power consumption?

It utilizes a proprietary shutdown mode that turns off the internal charge pumps and disables transmitter outputs. In this state, supply current drops to 10nA when receiver inputs are held in the invalid range.

What is the function of the MBAUD pin?

The MegaBaud control input allows the user to switch between standard operation (connected to GND) for 250kbps rates and high-speed operation (connected to VCC) for 1Mbps transmission rates.

Why are complementary receiver outputs provided?

The R_OUTB pins remain always active regardless of the enable or shutdown states. This allows the detection of RS-232 activity even when the main receiver outputs are tri-stated, preventing current flow into powered-down UARTs.