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Q. 4: Figure 4 depicts an MOS device based differential amplifier using active loads. Figure 4: (a) Draw the schematic of a similar differential pair amplifier using BJT devices. Assuming that the bias sources have infinite output resistances, find the small signal voltage gain vout/(vin1 − vin2) of the BJT based differential pair. You can use the half-circuit principle. The ac signals Vin1 , Vin2 form a balanced differential input signal pair. (b) It is given that Iss = 2 mA, Iss2 = 1 mA, VDD = 5 V, and the Early voltage VA = 50 V for all the transistors. The transistors are all identical.

Q. 4: Figure 4 depicts an MOS device based differential amplifier using active loads. Figure 4: (a) Draw the schematic of a similar differential pair amplifier using BJT devices. Assuming that the bias sources have infinite output resistances, find the small signal voltage gain vout/(vin1 − vin2) of the BJT based differential pair. You can use the half-circuit principle. The ac signals Vin1 , Vin2 form a balanced differential input signal pair. (b) It is given that Iss = 2 mA, Iss2 = 1 mA, VDD = 5 V, and the Early voltage VA = 50 V for all the transistors. The transistors are all identical.

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Q.4: Figure 4 depicts an MOS device based differential amplifier using active loads. Figure 4: (a) Draw the schematic of a similar differential pair amplifier using BJT devices. Assuming that the bias sources have infinite output resistances, find the small signal voltage gain v out / ( v in 1 − v in 2 ) of the BJT based differential pair. You can use the half-circuit principle. The a c signals V in1 , V in2 form a balanced differential input signal pair. (b) It is given that I s s = 2 m A , I s s 2 = 1 m A , V D D = 5 V , and the Early voltage V A = 50 V for all the transistors. The transistors are all identical.

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