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11-1Chapter Eleven

Differential

and

Multistage Amplifiers

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11-2Figure 11.2

Basic BJT differential-pair configuration

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11-3Figure 11.3Basic diff-amp with applied common-mode voltage and (b) basic diff-amp with applied differential-mode voltage

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11-4Figure 11.7(a) Equivalent ac circuit, diff-amp with differential-mode input signal and two-sided output voltage and (b) ac equivalent circuit with one-sided output

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11-5Figure 11.8

Small-signal equivalent circuit, bipolar differential amplifier

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11-6Figure 11.12

(a) Equivalent ac circuit, diff-amp with applied sinusoidal differential-mode input signal, and resulting signal current directions and (b) differential-mode half-circuits

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11-7Figure 11.13

(a) Equivalent ac circuit of diff-amp with common-mode input signal, and resulting signal current directions and (b) common-mode half circuits

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11-8Figure 11.22

AC equivalent circuit, MOSFET differential amplifier

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11-9Figure 11.23

Small-signal equivalent circuit, MOSFET differential amplifier

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11-10Figure 11.24

MOSFET cascode current source

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11-11Figure 11.28

BJT differential amplifier with active load

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11-12Figure 11.30

BJT differential amplifier with three-transistor active load, showing the signal currents

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11-13Figure 11.31

(a) Small-signal equivalent circuit BJT differential amplifier with active load and (b) rearrangement of small-signal equivalent circuit

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11-14Figure 11.33

The ac equivalent circuit, MOSFET differential amplifier with active load

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11-15Figure 11.34(a) Small-signal equivalent circuit, MOSFET differential amplifier with active load and (b) rearranged small-signal equivalent circuit

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11-16Figure 11.37A MOSFET cascode diff-amp with a cascode diff-amp

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11-17Figure 11.46

BJT diff-amp with three-transistor active load, Darlington pair gain stage, and simple emitter-follower output stage