Assume the current mirror of is implemented with perfectly matched BJTs having negligible base currents and VA 5 `. Moreover, let VCC 5 5 V and R XXXXXXXXXXkV. (a) Assuming VBE 5 700 mV and R2 is...

Assume the current mirror of is implemented with perfectly matched BJTs having negligible base currents and VA 5 `. Moreover, let VCC 5 5 V and R1 5 4.3 kV. (a) Assuming VBE 5 700 mV and R2 is small enough to ensure that Q2 is always in the FA region, fi nd IC2. (b) Suppose now Q2 experiences a temperature rise DT 5 1 8C relative to Q1. Given that the temperature coeffi cient of a pn junction is 22 mV/8C, Q2 would now need only 698 mV to carry the same current as Q1. Yet, Q1 is imposing 700 mV, so IC2 will be higher than before the temperature rise occurred. What is its new value? (c) Recalculate IC2 if Q2 experiences a temperature rise DT 5 5 8C relative to Q1. (d) Recalculate IC2 if now it is Q1 that experiences a temperature rise DT 5 10 8C relative to Q2. (e) If it is found that IC2 5 0.75 mA, what do you conclude?