1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
|
// Example 11.16: (a) AF, T
// (b) R1F, RoF
clc, clear
btao=150;
ICQ=1.5e-3; // in amperes
VT=25e-3; // Voltage equivalent to temperatue at room temperature in volts
// From circuit without feedback but with loading in Fig. 11.50
RS=2e3; // in ohms
RE1=0.1e3; // in ohms
RF=6.2e3; // in ohms
RC1=4.3e3; // in ohms
RC2=1.2e3; // in ohms
RL=4.7e3; // in ohms
function[c]=parallel(a,b)
c=a*b/(a+b);
endfunction
disp("Part (a)");
gm=ICQ/VT; // Transconductance in mho
r_pi=btao/gm; // Incremental resistance of emitter-base diode in ohms
AV1=-btao*RC1/(RS+r_pi+(1+btao)*parallel(RE1,RF));
AV2=-btao*parallel(RC2,parallel(RF+RE1,RL))/(RC1+r_pi);
AoL=AV1*AV2;
bta=-RE1/(RE1+RF);
T=-bta*AoL;
AF=AoL/(1+T);
disp(AF,"AF =");
disp(T,"T =");
disp("Part (b)");
RID=r_pi+(1+btao)*parallel(RE1,RF); // in ohms
RID_dash=RS+RID; // in ohms
RIF_dash=RID_dash*(1+T); // in ohms
RIF=RIF_dash-RS; // in ohms
RoD=parallel(RC2,RF+RE1); // in ohms
RoD_dash=parallel(RoD,RL); // in ohms
RoF_dash=RoD_dash/(1+T); // in ohms
RoF=RL*RoF_dash/(RL-RoF_dash); // in ohms
RIF=RIF*1e-3; // in kilo-ohms
disp(RIF,"RIF (kΩ) =");
disp(RoF,"RoF (Ω) =");
|
