Overcoming Limitations of Optocoupler and High Voltage Gate Driver Solutions

Isolated gate drivers provide electrical isolation as well as strong gate drive capability, which is often required for safety and robustness in many system architectures. The isolated gate driver portfolio from Analog Devices offers designers performance and reliability advantages over designs utilizing optocouplers or pulse transformers. Utilizing ADI’s proven iCoupler® technology, the isolated gate driver family offers the advantage of a maximum propagation delay of 50 ns, less than 5 ns channel-to-channel matching, a 50-year lifetime for 400 V rms working voltage and galvanic isolation in a single package.

Explore more advantages of iCoupler-based digital isolation products.

Existing Solutions Limitations ...
Optocoupler Gate Driver Solution Limitations
 Optocoupler-Based_Driver_Solution_sm
  • Poor Timing Performance
    • Requires longer dead-time effecting overall efficiency
    • Long propagation delays ≥350ns
    • Part-to-part variation ≥200ns
    • Difference between rise and fall times ≥100ns
  • LED Wearout
    • Limits the lifetime to <10 years of operation at high temperature
    • Most rated for operation to 85°C
 
 High Voltage Gate Driver Solution Limitations
 High-Voltage_Driver_Solution_sm
 
  • Latch-Up When Glitches Go
    Beyond the Supply Voltage
    • Rely on junction isolation which
      can breakdown and cause latch-up
    • Latch-up related shoot through
      best avoided with galvanic isolation
ADI's Solution ...
iCoupler Isolated Gate Drivers Overcome the Limitations of Optocoupler- and High Voltage-based Gate Drivers
 

Isolated_gate_driver_diagram
 
  • Small Single Package Solution
  • Fastest timing enables higher switching speeds for higher power densities
    and better efficiency in AC/DC converters, DC/DC converters, inverters, 
    motor control
  • Standard CMOS enables high-reliability at low cost
  • Balanced push-pull output stage simplifies gate driving
  • True galvanic isolation between outputs seperates high and low side minimizing cross conduction




  • Latch-Up When Glitches Go 
    Beyond the Supply Voltage
    • Rely on junction isolation which
      can breakdown and cause latch-up
    • Latch-up related shoot through
      best avoided with galvanic isolation 
  • Latch-Up When Glitches Go 
    Beyond the Supply Voltage
    • Rely on junction isolation which
      can breakdown and cause latch-up
    • Latch-up related shoot through
      best avoided with galvanic isolation 
  • Latch-Up When Glitches Go 
    Beyond the Supply Voltage
    • Rely on junction isolation which
      can breakdown and cause latch-up
    • Latch-up related shoot through
      best avoided with galvanic isolation 

Vist Product Pages For Data Sheets And Samples

  • ADuM3220: 4A Isolated Gate Driver with 2.5kV rms isolation, Overlap Protection and 4V or 7V UVLO
  • ADuM3221: 4A Isolated Gate Driver with 2.5kV rms isolation and 4V or 7V UVLO
  • ADuM3223: 4A Isolated Gate Driver with 3kV rms isolation, Selectable Overlap Protection and 4V, 7V or 11V UVLO
  • ADuM3224: 4A Isolated Gate Driver with 3kV rms isolation, without Thermal Shutdown and 4V, 7V or 11V UVLO
  • ADuM4223: 4A Isolated Gate Driver with 5kV rms isolation, Selectable Overlap Protection and 4V, 7V or 11V UVLO
  • ADuM4224: 4A Isolated Gate Driver with 5 kV rms isolation, without Thermal Shutdown and 4V, 7V or 11V UVLO
  • ADuM7223: Isolated, Precision Half-Bridge Driver, 4A Output

Evaluation Kits

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EVAL-ADUM7223 Circuit Diagram

Product Details

The EVAL-ADUM7223EBZ supports the ADuM7223 isolated precision half-bridge driver. Because the evaluation boards have footprints for IGBTs and MOSFETs in TO-252 packages, the ADuM7223 can be evaluated with many different power devices. The evaluation boards also allow the high-side supply to be bootstrapped to the low-side supply.

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The EVAL-ADUM7223EBZ supports the ADuM7223 isolated precision half-bridge driver. Because the evaluation boards have footprints for IGBTs and MOSFETs in TO-252 packages, the ADuM7223 can be evaluatedThe EVAL-ADUM7223EBZ supports the ADuM7223 isolated precision half-bridge driver. Because the evaluation boards have footprints for IGBTs and MOSFETs in TO-252 packages, the ADuM7223 can be evaluatedThe EVAL-ADUM7223EBZ supports the ADuM7223 isolated precision half-bridge driver. Because the evaluation boards have footprints for IGBTs and MOSFETs in TO-252 packages, the ADuM7223 can be evaluatedThe EVAL-ADUM7223EBZ supports the ADuM7223 isolated precision half-bridge driver. Because the evaluation boards have footprints for IGBTs and MOSFETs in TO-252 packages, the ADuM7223 can be evaluated

EVAL-ADUM3220 Circuit Diagram

Product Details

The EVAL-ADuM3221EBZ supports the ADuM3220/ ADuM3221 isolated gate drivers. It is compatible with IGBT/ MOSFETs in TO-263 or TO-252 packages. The evaluation board is ideal for evaluating the ADuM322x family with different power devices. It comes with an ADuM3221A installed.

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The EVAL-ADuM3221EBZ supports the ADuM3220/ ADuM3221 isolated gate drivers. It is compatible with IGBT/ MOSFETs in TO-263 or TO-252 packages. The evaluation board is ideal for evaluating the ADuM322xThe EVAL-ADuM3221EBZ supports the ADuM3220/ ADuM3221 isolated gate drivers. It is compatible with IGBT/ MOSFETs in TO-263 or TO-252 packages. The evaluation board is ideal for evaluating the ADuM322xThe EVAL-ADuM3221EBZ supports the ADuM3220/ ADuM3221 isolated gate drivers. It is compatible with IGBT/ MOSFETs in TO-263 or TO-252 packages. The evaluation board is ideal for evaluating the ADuM322xThe EVAL-ADuM3221EBZ supports the ADuM3220/ ADuM3221 isolated gate drivers. It is compatible with IGBT/ MOSFETs in TO-263 or TO-252 packages. The evaluation board is ideal for evaluating the ADuM322x

Additional Resources