The Bipolar Junction Transistor

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The Bipolar Junction Transistor

• A Bond Graph Model

Michael C. Schweisguth, Graduate Student
François E. Cellier, Professor
Dept. of Electrical
and Computer Engineering University of Arizona,
Tucson, Arizona, U.S.A.
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Contents

• The Circuit Model
• Translation to a Bond Graph
• Reformulation of the Bond Graph
• Simulation Results
• Physicality of the Model
• Conclusions

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The BJT Circuit Model
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The Junction Diode Model
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Translation to Bond Graph
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Reformulation of Bond Graph
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Simulation Results
time
50
200
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Physicality of the Model
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Conclusions

• The Bond Graph has helped identify a potential
  problem with the physicality of the BJT circuit
  model
• Manipulating the Bond Graph helped identify the
  true power flows through the device
• The Bond Graph helped to find the equations that
  prove that no power is ever generated by the
  current sources (which, in fact, are nothing but
  nonlinear resistors)
• The Bond Graph methodology ensured that the model
  representing the BJT is physically sound.