Consider the following simple amplifier noise model: Sna gain, G www Rs Ss • Rin Onis wwiny . ina noisy noise free amp a
Posted: Mon May 02, 2022 2:23 pm
Consider the following simple amplifier noise model: Sna gain, G www Rs Ss • Rin Onis wwiny . ina noisy noise free amp amp It can be shown that the total input noise density of the amplifier is: vž = vh, R. + 0,0 + in,a ; where 2. R. is the Johnson noise of the source resistance, given by v2. = 4TRş, and Un,alina 'n, are the intrinsic voltage/current noise densities of the amplifier. Assuming R, is an ideal resistor, so you can calculate v2 exactly, explain briefly how you could measure the two different types of amplifier noise. [Hint: Assume you have measured the amplifier gain, G, and can measure the noisy output voltage signal using a scope. You may also assume that you can vary R, controllably, e.g., by adding extra resistance in at the voltage source.] n,R