4-Wire-Interfaced, 2.5V to 5.5V, 20-Port and 28-Port I/O Expander

Please check latest availability status for a specific part variant.


The MAX7301 compact, serial-interfaced I/O expander (or general-purpose I/O (GPIO) peripheral) provides microprocessors with up to 28 ports. Each port is individually user configurable to either a logic input or logic output.

Each port can be configured either as a push-pull logic output capable of sinking 10mA and sourcing 4.5mA, or a Schmitt logic input with optional internal pullup. Seven ports feature configurable transition detection logic, which generates an interrupt upon change of port logic level. The MAX7301 is controlled through an SPI-compatible 4-wire serial interface.

The MAX7301AAX and MAX7301ATL have 28 ports and are available in 36-pin SSOP and 40-pin TQFN packages, respectively. The MAX7301AAI has 20 ports and is available in a 28-pin SSOP package.

For a 2-wire I²C-interfaced version, refer to the MAX7300 data sheet.

For a pin-compatible port expander with additional 24mA constant-current LED drive capability, refer to the MAX6957 data sheet.
MAX7301: Functional Diagram MAX7301: Functional Diagram Enlarge+

Key Features

  • Industry-Standard 4-Wire Interface Simplifies Expansion of I/O Ports to Up to 28 I/Os Independent of Microprocessor Architecture
    • High-Speed, 26MHz, SPI-/QSPI™-/MICROWIRE®-Compatible Serial Interface
    • 2.25V to 5.5V Operation
    • 20 or 28 I/O Ports Configurable as Push-Pull Logic Output, Schmitt Logic Input or Schmitt Logic Input with Internal Pullup
    • Logic Transition Detection for Seven I/O Ports
  • Low Power Consumption Reduces Power-Supply Requirements
    • 11µA (max) Shutdown Current


  • Gaming Machines
  • Industrial Controllers
  • System Monitoring
  • White Goods

See parametric specs for I/O Port Expanders (31)

Part NumberInterfaceI/OInterrupt OutputDrive Current
minmaxSee Notes
MAX7301 Serial SPI 26Mbit20 or 28Yes102.55.5
$3.52 @1k

Pricing Notes:
This pricing is BUDGETARY, for comparing similar parts. Prices are in U.S. dollars and subject to change. Quantity pricing may vary substantially and international prices may differ due to local duties, taxes, fees, and exchange rates. For volume-specific and version-specific prices and delivery, please see the price and availability page or contact an authorized distributor.

Tools & Models

  • MAX7301 IBIS Model
  • Product Reliability Reports: MAX7301.pdf 
    Device   Fab Process   Technology   Sample size   Rejects   FIT at 25°C   FIT at 55°C   Material Composition  

    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.

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    Environmental Management System >


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