MAX33250EELC+

Overview

The MAX33250EELC+ is a 600V RMS isolated RS-232 transceiver featuring two transmitters and two receivers. It operates on dual supplies of +3.0V to +5.5V for both logic (VCCA) and field (VCCB) sides, supporting data rates up to 1Mbps. The device integrates charge pumps, an inverter, and four internal capacitors to eliminate external high-voltage components. It provides ±15kV ESD HBM protection on the field side and breaks ground loops via galvanic isolation. Packaged in a 12-pin LGA (6mm x 6mm), it functions within a temperature range of -40°C to +85°C.

Feature Summary

• Galvanic isolation barrier rated at 600V RMS withstand voltage for 60 seconds and 200V RMS working voltage for over 50 years.
• Integrated dual charge pump and inverter generate required RS-232 voltages from single low-voltage supplies without external inductors or transformers.
• Four internal flying and reservoir capacitors reduce PCB footprint compared to discrete solutions.
• Field-side inputs and outputs feature ±15kV ESD Human Body Model protection suitable for frequent cable handling.

Applications

• Diagnostics Equipment
• POS Systems
• Industrial Equipment
• GPS Equipment
• Medical Equipment

Procurement Notes

Verify the component against the official Maxim Integrated datasheet revision 1 (November 2018). Confirm the package marking matches the 12-pin LGA configuration. Ensure the ordering suffix indicates lead-free/RoHS compliance as specified in the manufacturer's documentation. Cross-reference the part number with authorized distributors to confirm current production status and availability.

Selection Notes

Select this component when designing systems requiring robust isolation between UART logic and RS-232 field lines. It is suitable for environments with high common-mode noise or ground potential differences. The integrated capacitor design simplifies layout constraints. Consider the MAX33251E variant if only a single transmitter and receiver channel are required for space optimization.

Part Context

This device belongs to the MAX3325xE series of isolated RS-232 transceivers manufactured by Analog Devices / Maxim Integrated. It serves as a compact alternative to discrete isolator and transceiver combinations. The series includes the MAX33251E, which offers a 1Tx/1Rx configuration in the same package form factor.

Replacement Considerations

Public confirmed substitute: MAX33251EELC+. This variant shares the same package, isolation ratings, and electrical characteristics but provides only one transmitter and one receiver instead of two.

FAQ

Does the MAX33250EELC+ require external capacitors for its charge pumps?

No, the device integrates four internal capacitors (two flying and two reservoir) for the voltage doubler and inverter, eliminating the need for external high-voltage capacitors.

What is the maximum data rate supported by this transceiver?

The MAX33250E supports data rates up to 1Mbps while conforming to the EIA/TIA-232E standard.

How does the device handle undervoltage conditions on the power supplies?

Internal undervoltage lockout monitors VCCA and VCCB. If either supply dips below the threshold, all outputs on both sides are automatically controlled to a known state to prevent data corruption.