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A differential amplifier depicted in Figure 10.2 comprises 4 transistors where MOS transistors: μnCoxW/L = 0.2×10−3 A/V2, Vt = 0.5 V Bipolar transistors: VCE( sat) = 0.2 V. Assume that the two MOSFETs have an identical aspect (i.e. W/L) ratio and that the two BJTs have identical emitter areas. (d) Show that all the MOSFETs and BJTs are active for the zero-input condition, i.e. Vin = 0. (e) Find the maximum and minimum common-mode input voltages, i.e. the limits of operation where the circuit remains in active operation. [(b)−6.14 V ≤ Vin ≤ 7.5 V]

A differential amplifier depicted in Figure 10.2 comprises 4 transistors where MOS transistors: μnCoxW/L = 0.2×10−3 A/V2, Vt = 0.5 V Bipolar transistors: VCE( sat) = 0.2 V. Assume that the two MOSFETs have an identical aspect (i.e. W/L) ratio and that the two BJTs have identical emitter areas. (d) Show that all the MOSFETs and BJTs are active for the zero-input condition, i.e. Vin = 0. (e) Find the maximum and minimum common-mode input voltages, i.e. the limits of operation where the circuit remains in active operation. [(b)−6.14 V ≤ Vin ≤ 7.5 V]

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A differential amplifier depicted in Figure 10.2 comprises 4 transistors where MOS transistors: μnCoxW/L = 0.2×10−3 A/V2, Vt = 0.5 V Bipolar transistors: VCE( sat) = 0.2 V. Assume that the two MOSFETs have an identical aspect (i.e. W/L) ratio and that the two BJTs have identical emitter areas. (d) Show that all the MOSFETs and BJTs are active for the zero-input condition, i.e. Vin = 0. (e) Find the maximum and minimum common-mode input voltages, i.e. the limits of operation where the circuit remains in active operation. [(b)−6.14 V ≤ Vin ≤ 7.5 V]

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