Analog Electronics
The universal bias stabilization circuit is the most popular because

  IC equals to IE.
  its β sensitivity is low .
  voltage divider is heavily loaded by transistor base .
  IC does not depend on transistor characteristic.

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Analog Electronics
Optocouplers combine

 IGBTs and MOSFETs.
 SITs and BJTs.
 Power transistor and silicon transistor.
  Infrared light emitting diode and a silicon photo transistor.

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