7.1 Find the voltage gain and the input resistance of the amplifier shown in the figure 1. Assuming 𝛽 = 100.
7.2 The differential amplifier in figure 2 utilizes a resistor Rss to establish a 1-mA dc bias current. This amplifier uses a single 5-V supply and thus the dc common-mode voltage VCM cannot be
zero. Transistors 𝑄 and 𝑄 have 𝑘′ 𝑊 = 2.5 𝑚𝐴 , 𝑉 = 0.7 𝑉, 𝑎𝑛𝑑 𝜆 = 0. 1 2 𝑛𝐿 𝑉2𝑡
a) Find the required value of VCM.
b) Find the value of RD that results in a differential gain Ad of 8 V/V. c) determine the dc voltage as the drains.
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