2-Wire-Interfaced 16-Bit I/O Port Expander with Interrupt and Hot-Insertion Protection

2-Wire-Interfaced 16-Bit I/O Port Expander with Interrupt and hot-Insertion Protection for SMBus-Compatible and I²C-Compatible Applications

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The MAX7311 2-wire-interfaced expander provides 16-bit parallel input/output (I/O) port expansion for SMBus™ and I²C applications. The MAX7311 consists of input port registers, output port registers, polarity inversion registers, configuration registers, a bus timeout register, and an I²C-compatible serial interface logic compatible with SMBus. The system master can invert the MAX7311 input data by writing to the active-high polarity inversion register. The system master can enable or disable bus timeout by writing to the bus timeout register.

Any of the 16 I/O ports can be configured as an input or output. A power-on reset (POR) initializes the 16 I/Os as inputs. Three address select pins configure one of 64 slave ID addresses.

The MAX7311 supports hot insertion. All port pins, the active-low INT output, SDA, SCL and the slave address inputs AD0-2 remain high impedance in power down (V+ = 0V) with up to 6V asserted upon them.

The MAX7311 is available in 24-pin SO, SSOP, TSSOP, and thin QFN packages and is specified over the -40°C to +125°C automotive temperature range.

For applications requiring I/Os without pullup resistors, refer to the MAX7312 data sheet.
MAX7311: Block Diagram MAX7311: Block Diagram Enlarge+

Key Features

  • 400kbps I²C-Compatible Serial Interface
  • 2V to 5.5V Operation
  • 5V Overvoltage Tolerant I/Os
  • Supports Hot Insertion
  • 16 I/O Pins that Default to Inputs on Power-Up
  • 100kΩ Pullup on Each I/O
  • Open-Drain Interrupt Output (Active-Low INT)
  • Bus Timeout for Lock-Up-Free Operation
  • Noise Filter on SCL/SDA Inputs
  • 64 Slave ID Addresses Available
  • Low Standby Current (2.9µA typ)
  • Polarity Inversion
  • 4mm x 4mm, 0.8mm Thin QFN Package
  • -40°C to +125°C Operation


  • Industrial Control
  • Instrumentation and Test Measurement
  • Medical Equipment
  • PLCs
  • RAID Systems
  • Servers
Part NumberInterfaceI/OInterr.OutOver Voltage Protection
Drive Current
minmaxSee Notes
MAX7311 Serial 2-Wire 400kbit16Yes5.54025.5
SOIC (W)/24
$3.09 @1k
See All I/O Port Expanders (31)
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.

MAX7311EVKIT: Evaluation Kit for the MAX7311

Technical Documents

App Note 4418 I²C Interface Connects Compact Flash Card to Microcontroller
App Note 2199 Driving LEDs with Push-Pull Port Expander Outputs

Quality and Environmental Data

Product Reliability Reports: MAX7311.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 >


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