±15kV ESD-Protected +2.5V to +5.5V RS-232 Transceivers in UCSP and WLP

Please check latest availability status for a specific part variant.


The MAX3228E/AE and MAX3229E/AE are +2.5V to +5.5V powered EIA/TIA-232 and V.28/V.24 communications interfaces with low power requirements, high datarate capabilities, and enhanced electrostatic discharge (ESD) protection, in a chip-scale package (UCSP™) and WLP Package. All transmitter outputs and receiver inputs are protected to ±15kV using IEC 1000-4-2 Air-Gap Discharge, ±8kV using IEC 1000-4-2 Contact Discharge, and ±15kV using the Human Body Model.

The MAX3228E/AE and MAX3229E/AE achieve a 1µA supply current with Maxim’s AutoShutdown™ feature. They save power without changes to existing BIOS or operating systems by entering low-power shutdown mode when the RS-232 cable is disconnected, or when the transmitters of the connected peripherals are off.

The transceivers have a proprietary low-dropout transmitter output stage, delivering RS-232 compliant performance from a +3.1V to +5.5V supply, and RS-232 compatible performance with a supply voltage as low as +2.5V. The dual charge pump requires only four small 0.1µF capacitors for operation from a +3.0V supply. Each device is guaranteed to run at data rates of 250kbps while maintaining RS-232 output levels.

The MAX3228E/AE and MAX3229E/AE offer a separate power-supply input for the logic interface, allowing configurable logic levels on the receiver outputs and transmitter inputs. Operating over a +1.65V to VCC range, VL provides the MAX3228E/AE and MAX3229E/AE compatibility with multiple logic families.

The MAX3229E/AE contains one receiver and one transmitter. The MAX3228E/AE contains two receivers and two transmitters. The MAX3228E/AE and MAX3229E/AE are available in tiny chip-scale and WLP packaging and are specified across the extended industrial temperature range of -40°C to +85°C.
MAX3228E, MAX3229E: Typical Operating Circuit MAX3228E, MAX3229E: Typical Operating Circuit Enlarge+

Key Features

  • 6 × 5 Chip-Scale Package (UCSP) and WLP Package
  • ESD Protection for RS-232 I/O Pins:
    • ±15kV—IEC 1000-4-2 Air-Gap Discharge
    • ±8kV—IEC 1000-4-2 Contact Discharge
    • ±15kV—Human Body Model
  • 1µA Low-Power AutoShutdown
  • 250kbps Guaranteed Data Rate
  • Meets EIA/TIA-232 Specifications Down to +3.1V
  • RS-232 Compatible to +2.5V Allows Operation from Single Li+ Cell
  • Small 0.1µF Capacitors
  • Configurable Logic Levels


  • Cell Phone Data Lump Cables
  • Cell Phones
  • Handheld Devices
  • Personal Digital Assistants (PDAs)
  • Set-Top Boxes

Technical Documents

Tutorial 2141 Determining Clock Accuracy Requirements for UART Communications
Tutorial 1834 Lower the Supply Current in Your RS-232 System

Quality and Environmental Data

Product Reliability Reports: MAX3228E.pdf 
Lead-Free Package Tin (Sn) Whisker Reports
Device   Fab Process   Technology   Sample size   Rejects   FIT at 25°C   FIT at 55°C  

Note : The failure rates are summarized by technology and mapped to the associated material part numbers. The failure rates are highly dependent on the number of units tested.

Quality Management System >
Environmental Management System >


Related Resources

IO-Link Transceiver with Integrated Protection

  • High Configurability and Integration Reduces SKU
  • Integrated Protection Enables Robust Systems
  • Optimized for Small Designs

100Mbps Full-Duplex 3V/5V RS-485/RS-422 Transceiver with High EFT Immunity

  • High-Speed Operation
  • Integrated Protection Increases Robustness
  • Flexibility for Many Different Applications