Features and Benefits

  • Single RS-232 Transceiver in a Small 16-Pin TSSOP
  • ESD Protection for RS-232 I/O Pins
    • ±15kV-Human Body Model
    • ±8kV-IEC 1000-4-2, Contact Discharge
    • ±15kV-IEC 1000-4-2, Air-Gap Discharge
  • Latchup Free
  • 1µA Supply Current
  • AutoShutdown Saves Power without Changes to BIOS
  • Guaranteed 250kbps Data Rate

Product Details

The MAX221E is a +5V powered, single transmit/receive RS-232 and V.28 communications interface with automatic shutdown/wake-up features and high data rate capabilities.

The MAX221E features enhanced electrostatic discharge (ESD) protection. Both the transmitter output and receiver input are protected to ±15kV using the IEC 1000-4-2 Air-Gap Discharge Method, to ±8kV using the IEC 1000-4-2 Contact Discharge Method, and to ±15kV using the Human Body Model.

The MAX221E achieves a low 1µA supply current with Maxim's revolutionary AutoShutdown™ feature. AutoShutdown saves power without changes to the existing BIOS or operating system by entering low-power shutdown mode when the RS-232 cable is disconnected or when the transmitter of the connected peripheral is off. The MAX221E wakes up and drives the active-low INVALID pin high when an active RS-232 cable is connected, signaling the host that a peripheral is connected to the communications port.

The MAX221E is available in a 16-pin SSOP package as well as a 16-pin TSSOP that uses 50% less board space than a 16-pin SO.


  • Industrial Systems
  • Maintenance/Diagnostic Ports
  • Set-Top Boxes
  • Telecommunications

Product Lifecycle icon-recommended Production

At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.

Product Recommendations

MAX221E Companion Parts

Design Resources

ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well.  "Zero defects" for shipped products is always our goal.

PCN-PDN Information

Sample & Buy

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Buy Now Pricing

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List Pricing

(*)The 1Ku list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.


Lead Times

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