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For the current-mirror-loaded BJT differential amplifier in Figure 1, let I = 0.6 mA, VA = 120 V, and β = 120. Find differential gain Ad = vo/vid and differential input resistance Rid. vid = vB1 - vB2

For the current-mirror-loaded BJT differential amplifier in Figure 1, let I = 0.6 mA, VA = 120 V, and β = 120. Find differential gain Ad = vo/vid and differential input resistance Rid. vid = vB1 - vB2

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For the current-mirror-loaded BJT differential amplifier in Figure 1, let I = 0.6 mA, VA = 120 V, and β = 120. Find differential gain Ad = vo/vid and differential input resistance Rid. vid = vB1 - vB2

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Figure Q2 shows a BJT differential amplifier stage that uses a tail resistor, RO, to provide a bias current, IQ. Transistor parameters are VBE(on) = 0.7 V, β = 100, and VA = ∞. Also, Vcc = 15 V, −VEE = −15 V, RO = 56 kΩ, and RC = 15 kΩ. Figure Q2: Differential Amplifier (a) To calculate the transistor Q-points, what are the values you would assume for vB1 and vB2 ? (b) Determine the bias currents, IC1 and IC2, of the amplifier. (c) For a single-sided output, determine the differential-mode voltage gain (Ad), the commonmode voltage gain (Acm), the differential input impedance (Rid), the common-mode input impedance (Ricm), and the common-mode rejection ratio (CMRR) in dB for the differential amplifier. Assume a signal source resistance of 50 Ω on each input. (d) Will changing RC affect the amplifier CMRR? (e) Suggest two changes to this amplifier each of which would allow the CMRR to be increased. For each, give a reason why the change would have the desired effect.

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