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1. BJT device structure 2. DC characteristics 3. ac small signal equivalent circuit 4. Frequency response
Lecture 4, Oct. 8, 2004
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1. Ch. 1, P. R. Gray and R. G. Meyer, Analysis and Design of Analog Integrated Circuits, 3rd ed., 1993, John Wiley & Sons, Inc.
BJT Device Structure
BJT Cross-section showing the parasitics
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Figure 1: BJT cross-section
Ebers-Moll
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Figure 2: Ebers-Moll
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Based on the interacting diode junctions Applicable to any operating mode Four model parameters: IES , ICS , αF , αR . But because of the reciprocity relationship , only three are independent.
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αF IES = αR ICS
(1)
DC Characteristics (1st-order)
IC = αF IES exp VBE VT 1 ICS exp VBC VT 1 0) (2)
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Forward-active operation region of an npn BJ……
