Features and Benefits

  • 28V Protection on EXT
  • Extended ESD Protection
    • ±4kV IEC 61000-4 Contact on EXT
  • +2.2V to +5.5V Supply Voltage Range
  • 13µA Quiescent Supply Current
  • 60ns Fault Reaction Time
  • Small, 5-Pin SC70
  • -40°C to +125°C Temperature Range

Product Details

The MAX9940 signal-line overvoltage protector for low-voltage digital communication ports provides protection against high-voltage faults and ESD strikes. The MAX9940 is especially useful for sensitive communication protocols such as Maxim 1-Wire® that cannot afford standard means of fault protection, such as large series resistors or large line capacitances.

The MAX9940 operates from a single supply voltage of +2.2V to +5.5V and consumes only 13µA of quiescent supply current. The EXT port is protected up to 28V. The device features a reaction time of 60ns for fast action during fault conditions and operates over the -40°C to +125°C automotive temperature range.


  • Industrial Equipment
  • Notebook Computers
  • Portable Devices

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.

Evaluation Kits (1)

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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.

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(*)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.



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Evaluation Boards

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Pricing displayed is based on 1-piece. The USA list pricing shown is for budgetary use only, shown in United States dollars (FOB USA per unit), and is subject to change. International prices may vary due to local duties, taxes, fees and exchange rates.