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Lecture 4

February 17, 2015

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EEE 312 Electronic Circuits

BJT AC Analysis

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DARLINGTON CONNECTION

• A very popular connection of two bipolar junction transistors foroperation as one “super- beta” transistor is the Darlingtonconnection shown in Figure

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DARLINGTON CONNECTION-Emitter Follower

• DC Bias

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DARLINGTON CONNECTION-Emitter Follower

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DARLINGTON CONNECTION-AC input impedance

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DARLINGTON CONNECTION-AC Current Gain

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DARLINGTON CONNECTION-AC Voltage Gain

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DARLINGTON CONNECTION-AC Output Impedance

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DARLINGTON CONNECTION-AC Output Impedance

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DARLINGTON CONNECTION-Voltage Divider

• DC Bias

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DARLINGTON CONNECTION-Voltage Divider

• AC Input Impedance

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DARLINGTON CONNECTION-Voltage Divider

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• AC Current Gain

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DARLINGTON CONNECTION-Voltage Divider

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FEEDBACK PAIR

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FEEDBACK PAIR

• AC Operation

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FEEDBACK PAIR

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• AC Operation

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FEEDBACK PAIR