Features and Benefits

  • 1:2 2-Wire Multiplexer/Switch
  • Connect SDA and SCL Lines with 2-Wire Bus
  • Supply Independent Bidirectional Buffer for SDA
    and SCL Lines Increases Fan-Out
  • Programmable Disconnect from Stuck Bus
  • Compatible with I2C and SMBus Standards
  • Rise Time Accelerator Circuitry
  • SMBus Compatible ALERT Response Protocol
  • Prevents SDA and SCL Corruption During Live Board
    Insertion and Removal from Backplane
  • ±10kV Human Body Model ESD Ruggedness
  • 16-Lead (4mm × 5mm) DFN and SSOP Packages

Product Details

The LTC4305 is a 2-channel, 2-wire bus multiplexer with bus buffers to provide capacitive isolation between the upstream bus and downstream buses. Through software control, the LTC4305 connects the upstream 2-wire bus to any desired combination of downstream channels. Each channel can be pulled up to a supply voltage ranging from 2.2V to 5.5V, independent of the LTC4305 supply voltage. The downstream channels are also provided with an ALERT1-ALERT2 inputs for fault reporting.

Programmable timeout circuitry disconnects the downstream buses if the bus is stuck low. When activated, rise time accelerators source currents into the 2-wire bus pins to reduce rise time. Driving the ENABLE pin low restores all features to their default states. Three address pins provide 27 distinct addresses.

The LTC4305 is available in 16-lead (4mm × 5mm) DFN and SSOP packages.


  • Nested Addressing
  • 5V/3.3V Level Translator
  • Capacitance Buffer/Bus Extender

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.

Tools & Simulations

IBIS Models

LTC4305 IBIS Model GN Package

16 Lead Plastic SSOP

LTC4305 IBIS Model DHD Package

16 Lead (4mm x 5mm) Plastic DFN

Product Recommendations

LTC4305 Companion Parts

Recommended µModule Isolator

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.

PCN-PDN Information

Sample & Buy

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