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For the differential amplifier in Fig. 3, the parameters are given as R1 = 10 kΩ and R2 = 5 kΩ. Assume all transistors are in saturation with a small-signal transconductance (gm) of 1 mA/V, and the output resistance of the current sources is 10 kΩ. (a)If the devices are matched, find the differential gain (Ad), common-mode gain (Acm) and common-mode rejection ratio (CMRR) of the amplifier. (10%) (b)Assume that the resistance has 1% mismatch. Find the differential gain (Ad), common-mode gain (Acm) and common-mode rejection ratio (CMRR) of the amplifier. (10%) (c)For 1% resistance mismatch, what is required output resistance of the current sources to achieve a CMRR of 140 dB ? (10%)

For the differential amplifier in Fig. 3, the parameters are given as R1 = 10 kΩ and R2 = 5 kΩ. Assume all transistors are in saturation with a small-signal transconductance (gm) of 1 mA/V, and the output resistance of the current sources is 10 kΩ. (a)If the devices are matched, find the differential gain (Ad), common-mode gain (Acm) and common-mode rejection ratio (CMRR) of the amplifier. (10%) (b)Assume that the resistance has 1% mismatch. Find the differential gain (Ad), common-mode gain (Acm) and common-mode rejection ratio (CMRR) of the amplifier. (10%) (c)For 1% resistance mismatch, what is required output resistance of the current sources to achieve a CMRR of 140 dB ? (10%)

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  1. ( 30 % ) For the differential amplifier in Fig. 3, the parameters are given as R 1 = 10 k Ω and R 2 = 5 k Ω . Assume all transistors are in saturation with a small-signal transconductance ( g m ) of 1 m A / V , and the output resistance of the current sources is 10 k Ω . (a)If the devices are matched, find the differential gain ( A d ) , common-mode gain ( A c m ) and common-mode rejection ratio (CMRR) of the amplifier. (10%) (b)Assume that the resistance has 1 % mismatch. Find the differential gain ( A d ) , common-mode gain ( A c m ) and common-mode rejection ratio (CMRR) of the amplifier. (10%) (c)For 1 % resistance mismatch, what is required output resistance of the current sources to achieve a CMRR of 140 d B ? ( 10 % )

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