Chapter 5 Transistor Bias Circuit

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Chapter 5 Transistor Bias Circuit
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DC Bias

• Bias establishes the dc operating point (Q-point)
  for proper linear operation of an amplifier.

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Collector Characteristic Curves
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DC Load Line
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Operating Point (Q points)
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Linear Operation
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Symbol

• Only DC Quantaties
• VBE
• Coupled AC Quantaties
• 
  Vbe

Upper case
Upper case subscription
Upper case
lower case subscription
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Linear Operation
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Calculate Q points

• Calculate
• Assumption when calculate Q -points

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Emitter Bias
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Base Bias
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Emitter-Feedback Bias
Base Bias
Emitter Feedback Bias
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Emitter Feedback Bias
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Collector Feedback Bias
Base Bias
Collector Feedback Bias
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Collector Feedback Bias
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Voltage Divider Bias
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Voltage Divider Bias
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Voltage Divider Bias
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Voltage Divider Bias
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Voltage Divider Bias

• Stiff voltage divide

Stiff
Stiff
Criterion for Stiff
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Stiff Voltage Divider Bias
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Voltage Divider Bias

• Procedure for analyze voltage divider bias
• Check stiffness
• If Stiff
  else
• 
  Thevenin equivalent
  circuit