biased to operate in the active mode. Assuming that B is very large, find the collector bias current I. Replace the transistor with the small-signal equivalent-circuit model of Fig. 7.27(b) (remember to replace the de power supply with a short circuit). Analyze the resulting amplifier equivalent circuit to show that RE R, +r, -aR. Rf+r, Find the values of these voltage gains (for a 1). Now, if the terminal labeled v, is connected to ground, what does the voltage gain v/v, become? +5 V Re = 3.3 k2 100 kn 100 kN R = 3.6 kN

Consider the circuit depicted in the figure shown below. This circuit is designed using a silicon bipolar junction transistor (BJT) with a forward current gain BF = 100, and two resistances RB = 1kN and Rc = 1kN. The supply voltage is Vcc = 10 volts. The currents Ig and Ic designate the base and collector currents, respectively, whereas the voltage VCẸ denotes the voltage between collector and emitter. Vcc = 10 volts Rc =1 k2 Rg = 1 k2 VCE GND Throughout this question, you will use VBE,on = 0.7 volt and VCE,sat = 0.2 volt. Recall that VBE.on is the threshold voltage of the base-emitter junction, while VCE.sat represents the voltage that is measured between collector and emitter when the BJT is saturated. a) What is the value of the base current In? Please enter the value expressed in milliamperes (mA) in the box below. For instance, if you think that IR = 0.1 A, enter 100 in the box. If you think that Ip = 10 mA, enter 10 in the box. mas-numbas-Iti.ncl.ac.uk Submit part Unanswered b)…

For the circuit shown in Fig. P7.53. draw a complete small-signal equivalent circuit utilizing an appropriate T model for the BJT (use alpha= 0.99). Neglect the transistor output resistance r0. Your circuit should show the values of all components, including the model parameters. What is the input resistance Rin? Calculate the overall voltage gain (vo/vsig).

8. A. How does a common source amplifier compare to a common emitter amplifier in terms of its input resistance, its output resistance, and its voltage amplification? Give typical values for each type of amplifier when operating at 1mA. B. When would you choose a common emitter amplifier verses a common source amplifier and vice versa and why so? C. When would you choose a common collector amplifier and when would you choose a common base amplifier and why so? D. When would you choose an operational amplifier instead of a common emitter or common source amplifier and why so?

1. Assume a student wanted to supply more current than the rated 1 A for the series pass transistor by placing a second identical pass transistor in parallel with the first. a) What problem does this create? b) Why isn't is a problem if MOSFET transistors were used? (Ctrl)