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| Differential
Amplifier and |
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| Common-Mode
Signals |
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| • | Basic
differential amplifier |
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| – | Q1
identical to Q2 |
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| – | RC1
= RC2 |
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| – | IC1
= IC2 and emitter currents equal |
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| – | Also, IC
≈ IE
for high β |
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| – | and VBE
≈ 0.7 V |
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| • | Similar
calculation of Bias |
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