CHAPTER 4
Bipolar Junction Transistors (BJTs)
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Figure 4.1 A simplified structure of the npn transistor.
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Figure 4.2 A simplified structure of the pnp transistor.
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Figure 4.7 Cross-section of an npn BJT.
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Figure 4.8 The characteristic of an npn transistor fed with a constant emitter current . The transistor enters the saturation
mode of operation for , and the collector current diminishes.
Microelectronic Circuits, Seventh Edition
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Figure 4.12 Circuit symbols for BJTs.
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Figure 4.13 Voltage polarities and current flow in transistors biased in the active mode.
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Figure 4.23 Analysis of the circuit for Example 6.4: (a) circuit; (b) circuit redrawn to remind the reader of the convention used in this book to
show connections to the power supply; (c) analysis with the steps numbered.
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Figure 4.24 Analysis of the circuit for Example 6.5. Note that the circled numbers indicate the order of the analysis steps.
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Figure 4.25 Example 4.6: (a) circuit; (b) analysis, with the order of the analysis steps indicated by circled numbers.
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Figure 4.26 Example 4.7: (a) circuit; (b) analysis, with the steps indicated by circled numbers.
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Figure 4.27 Example 4.8: (a) circuit; (b) analysis, with the steps indicated by the circled numbers.
Microelectronic Circuits, Seventh Edition
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Figure 4.28 Example 4.9: (a) circuit; (b) analysis with steps numbered.
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Figure 4.29 Circuits for Example 4.10.
Microelectronic Circuits, Seventh Edition
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