The insulated Gate Bipolar Transistor (IGBT) was invented in the 1970s and can be thought off as a hybrid of a high power bipolar junction transistor and a MOSFET. It has the high power characteristics of a BJT but is voltage controlled like a MOSFET. It is used in applications where a high current must be switched by a low current control circuit.

IGBTs can be found in switch mode power supplies, defibrillators and driving circuits for the field coils in some MAGLEV trains.


These are the most used
symbols for the IGBT
          
                          _ E
         _ E              \|       
    __ | \|          __ |/ 
   G  ||/           G  |:   
      ||       OR      ||\  
      ||\              |:_ 
       | \             '|\|   
          C                \  C


G  Gate
C  Collector
E  Emitter