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, and two resistances Rc and Rp. The supply voltage is denoted as Vc. The voltages Vin and Vout designate the input and output voltages, respectively, whereas the currents IB, Ic and IE denote the base, collector, and emitter currents, respectively. VcC RC IB V out V in RE GND Throughout this question, we will also be using the following notations: VBE designates the voltage between base and emitter. VRE on denotes the threshold voltage of the base-emitter junction. For a silicon BJT, we have VBE.on0.7 volt. VCe designate the voltage between collector and emitter. Assume now that the BJT is in the saturation mode. What is the expression of the output voltage Vout? O Vout = Vin - VCE,sat O Vout = VBE,on + VCE,sat O Vout Vin - VBE,on + VCE,sat %3D o Vout Vin + VBE,on + VCE,sat o Vout = 0 o Vout = VBE,on O Vout = VBE,on - VCE,pat %3D O Vout = VCE,sat f) What is the condition that Vin must satisfy for the BJT to be in the saturation mode? RE Rc Re O Vin > VBE,on + - (Vcc - VCE,sat) O Vin < VBE,0on · (Vcc - VCE,sat) Rg Re O Vin > VBE,on + (Vcc- VCE, sat) RE O Vin < VBE,on Rc - (Vcc - VCE, sat) RE RE Rc o Vin > VBE,on +(R+Re) (Vcc :- VCE, sat) o Vin > VBE,on + (ReR) (Vcc - VcE,sat) Rg+Rc Rc O Vin < VBE.om +(RR) (Vcc - VCE sat) O Vin < VBE,om+ Rg+Re) (Vcc – VCE, sat) Rg+Rc

8.

"Bias voltage applied to the emitter electrode of a transistor offers greater stability over bias toward its base." Why?  How does that actually work?   My professor wants a detailed, engineering level explanation for this, and I am struggling to understand this to the degree he is asking.  He says having both a positive and negative voltage source at the emitter bias is not necessary, and won't accept this as part of the explanation. Thanks!

b) For correct operation as an ac amplifier a npn BJT must be correctly DC biased to establish an appropriate Q-point, i.e a negative voltage VBC between the base and collector terminals and a positive voltage VBE between the base and emitter terminals. Figure 3.1 shows a circuit that can achieve this requirement. Explain the role of each resistive element in this circuit. Vin RB1 Cin HH iin RB2 + Rc VB RE + Vcc Vc Cout VE ww 11 Figure 3.1 th Vout Ce İout