BJT Transistors and Characteristics

ELEC 121

January 2004 ELEC 121 2

Introduction to BJT’s• Introduction to BJT’s• BJT Specification Sheets• BJT Characteristic Family of Curves• BJT Circuit Simulation – DC Bias• BJT Bias Circuits

– Fixed-Bias Circuit– Emitter-Stabilized Bias Circuit– Collector-Emitter Loop– Voltage Divider Bias Circuit– DC Bias with Voltage Feedback– Miscellaneous Bias Circuits

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The NPN BJT

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NPN Biasing

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Example of Transistor Bias

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Input Characteristics of a Common-Base Amp

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Output Characteristics of a Common-Base Amp

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Voltage Gain in a PNP Transistor

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NPN CE Amplifier Characteristics

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Transistor Specifications

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Circuit to display Characteristic Curves

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Collector Characteristic Curves

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Common-emitter characteristics displaying exaggerated secondary effects

Characteristic Curves Secondary Effects

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Maximum Power Curve for BJT

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PNP Transistor

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PNP Characteristics

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PSpice Simulation for Family of Curves

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DC Sweep Primary Sweep

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DC Sweep Secondary Sweep

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Probe Output for Family of Curves