Features and Benefits

  • Serial-to-Parallel or Parallel-to-Serial Conversions
  • 8 General-Purpose Digital I/O Pins (withstand +28V)
  • SMBus 2-Wire Serial Interface
  • Supports SMBSUS-bar Asynchronous Suspend
  • 9 Pin-Selectable Slave Addresses
  • Outputs High Impedance on Power-Up (MAX1609)
  • Outputs Low on Power-Up (MAX1608)
  • 2.5µA Supply Current
  • +2.7V to +5.5V Supply Range
  • 16-Pin QSOP Package

Product Details

The MAX1608/MAX1609 provide remote input/output (I/O) expansion through an SMBus™ 2-wire serial interface. Each device has eight high-voltage open-drain outputs that double as TTL-level logic inputs, providing continuous bidirectional capabilities. The open-drain outputs tailor the MAX1608/MAX1609 for use in load-switching and other level-shifting applications as well as general-purpose I/O applications.

Two complete sets of registers allow the device and its outputs to be toggled between two states using the active-low SMBSUS input, without the inherent latency of reprogramming outputs over the serial bus. The eight I/O lines are continuously monitored and can be used as inputs. Each line can generate asynchronous maskable interrupts on the falling edge, the rising edge, or both edges.

For load-switching applications, the MAX1608 is designed to drive N-channel MOSFETs, and its outputs are low upon power-up; the MAX1609 is designed to drive P-channel MOSFETs, and its I/Os are high impedance upon power-up. Other features of both devices include thermal-overload and output-overcurrent protection, ultra-low supply current, and a wide +2.7V to +5.5V supply range. The MAX1608/MAX1609 are available in space-saving 16-pin QSOP packages.


  • Industrial Equipment
  • Notebook and Desktop Computers
  • Notebook Docking Stations
  • Parallel I/O Expansion
  • Power-Plane Switching
  • Servers and Workstations

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

MAX1609 Companion Parts

Recommended Related 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.

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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.


Lead Times

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