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Figure 4.1 The npn BJT.
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Figure 4.2 An npn transistor with variable biasing sources (common-emitter configuration).
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Figure 4.3 Current flow for an $npn$ BJT in the active region. Most of the current is due to electrons moving from the emitter through the base to the collector. Base current consists of holes crossing from the base into the emitter and of holes that recombine
with electrons in the base.
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Figure 4.4 Common-emitter characteristics of a typical npn BJT.
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Figure 4.5a Common-emitter characteristics displaying exaggerated secondary effects.
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Figure 4.5b Common-emitter characteristics displaying exaggerated secondary effects.
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Figure 4.6 Circuit for displaying BJT characteristic curves.
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Figure 4.9 Collector characteristics.
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Figure 4.10 Common-emitter amplifier.
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Figure 4.11 Load-line analysis of the amplifier of Figure 4.10.
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Figure 4.12a Load-line analysis for Example 4.2.
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Figure 4.12b Load-line analysis for Example 4.2.
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Figure 4.13 Voltage waveforms for the amplifier of Figure 4.10. See Example 4.2.
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Figure 4.14 Output of the amplifier of Example 4.2 for vin (t) = 1.2 sin(2000p t) showing gross distortion.
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Figure 4.15 Amplification occurs in the active region. Clipping occurs when the instantaneous operating point enters saturation or cutoff. In saturation, vCE < 0.2 V.
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Figure 4.16 The pnp BJT.
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Figure 4.17 Common-emitter characteristics for a pnp BJT.
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Figure 4.18 Common-emitter amplifier for Exercise 4.8.
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Figure 4.19a BJT large-signal models. (Note: Values shown are appropriate for typical small-signal silicon devices ata temperature of 300K.
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Figure 4.19b BJT large-signal models. (Note: Values shown are appropriate for typical small-signal silicon devices ata temperature of 300K.
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Figure 4.19c BJT large-signal models. (Note: Values shown are appropriate for typical small-signal silicon devices ata temperature of 300K.
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Figure 4.20 Regions of operation on the characteristics of an npn BJT.
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Figure 4.21 Bias circuit of Examples 4.4 and 4.5.
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Figure 4.22 Circuit for Example 4.4.
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Figure 4.25 Load lines for Examples 4.4 and 4.5.
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Figure 4.26 Circuit for Exercise 4.12.
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Figure 4.27 Circuit for Example 4.6.
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Figure 4.28a Four-resistor bias circuit.
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Figure 4.28b Four-resistor bias circuit.
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Figure 4.29 Circuit for Example 4.7.
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Figure 4.30 Current sources are useful in biasing IC amplifiers.
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Figure 4.31 Circuit for Exercise 4.18.
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Figure 4.32 Illustration of the Q-point base current IBQ, signal current i b(t), and total current iB(t).
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Figure 4.33 Small-signal equivalent circuits for the BJT.
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Figure 4.34a Common-emitter amplifier.
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Figure 4.34b Common-emitter amplifier.
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Figure 4.34c Common-emitter amplifier.
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Figure 4.35 Common-emitter amplifier of Example 4.9.
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Figure 4.36a Emitter follower.
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Figure 4.36b Emitter follower.
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Figure 4.36c Emitter follower.
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Figure 4.37a Emitter follower of Example 4.10.
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Figure 4.37b & c Emitter follower of Example 4.10.
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Figure 4.38 Common-base amplifier.
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Figure 4.39 Variation of the common-emitter amplifier.
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Figure 4.40 Small-signal equivalent circuit for the amplifier of Figure 4.39.
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Figure 4.41 RTL inverter.
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Figure 4.42a Load-line analysis of RTL inverter under no-load conditions.
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Figure 4.42b Load-line analysis of RTL inverter under no-load conditions.
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Figure 4.43 Transfer characteristic for RTL inverter under no-load conditions.
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Figure 4.44 Plots for Exercise 4.26.
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Figure 4.45 Three-input RTL NOR gate.
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Figure 4.46 RTL inverter.
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Figure 4.49 RTL inverter waveforms.
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Figure 4.50 Waveforms illustrating turn-on and turn-off times.
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Figure 4.51 The speed-up capacitor CS and Schottky clamp diode D1 dramatically reduce the switching times of the RTL inverter.
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Figure 4.53 Waveforms of the Schottky-clamped RTL inverter.