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Amplifiers: Variants
Here, we report some variants of the congurations already discussed and
analyzed to improve the performance of some of the ampliers.
In particular, we will deal with the methods used to increase the amplier’s
input resistance value (Section 10.2.2 in Chapter 10), to increase the known low
efciency of the class A topology (Section 10.2.4), to increase the bandwidth
(Section 10.2.6) and, nally, to increase the signal to noise ratio (Section 10.2.9)
with the rejection of unwanted signals that can couple into the input.
13.1 INCREASED INPUT RESISTANCE
We already discussed and evaluated (particularly, but not exclusiv