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[FAQ] What is a functional Isolator?

What is a functional Isolator?

  • Definition: Isolators with functional isolation protect and pass signals between two components that have a large ground potential difference.

    • Functional Isolators are great solutions for non-safety galvanic isolation required for seamless operation of the systems.

    Listed below are some differences between Functional, Basic, and Reinforced Isolation.


    Functional Isolation

    Basic Isolation

    Reinforced Isolation


    Isolation required to support proper function of the equipment

    Isolation of hazardous-live-parts which provides basic protection

    Isolation of hazard-live parts which provides a degree of protection against electric shock equivalent to double insulation

    Typical application examples

    Infotainment, Power Delivery, Test and Measurement

    Traction Inverter

    EV Charging Station





    Example Devices










    D, DBQ, DW

    DW, DWV, DWW


    Shown below is the package comparison between functional, basic, and reinforced isolation. The image is to scale and is shown below:

    TI Functional isolators are available in REU package size and use less space on the PCB. The area of the REU package (6mm^2) is 80% less area than the D package (29.5mm^2). Since the REU package is a leadless package, less board space is used and can allow for more compact designs.