
Ampliers
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is called amplication. The opposite is attenuation when the signal gets
reduced, as occurs in a passive lter.
➜ A DC amplier operates when there is no signal but only static voltage or
current is at its input. An AC amplier operates when a signal is at its input
port and its output voltage changes with changing voltage drop across a load
impedance.
➜ The key main parameters for ampliers are gain, impedances, efciency,
class, stability, bandwidth, slew rate, distortion, and noise.
➜ The classes A, B, AB, and C refer to the way the ampliers are biased in
comparison to the amplitude of the input signal. Class A preserves the ...