2 # $Id: electron.dem,v 1.7.2.1 2007/08/12 18:37:10 sfeam Exp $
6 # Bipolar Transistor (NPN) Mutual Characteristic
7 Ie(Vbe)=Ies*exp(Vbe/kT_q)
8 Ic(Vbe)=alpha*Ie(Vbe)+Ico
19 set title "Mutual Characteristic of a Transistor"
20 set xlabel "Vbe (base emmitter voltage)"
22 set ylabel "Ic (collector current)"
23 set yrange [0 : 0.005]
30 pause -1 "Hit return to continue"
32 # Junction Field Effect Transistor (JFET) Mutual Characteristic
33 # drain current above pinch off
34 Ida(Vd)=Ido*(1-Vg/Vp)**2
35 # drain current below pinch off
36 Idb(Vd)=Ido*(2*Vd*(Vg-Vp)-Vd*Vd)/(Vp*Vp)
38 Id(Vd)= (Vd>Vg-Vp) ? Ida(Vd) : Idb(Vd)
39 # drain current at zero gate voltage
48 #set offsets 0, 1, 0, 0
49 set title "JFET Mutual Characteristic"
50 set xlabel "Drain voltage Vd (V)"
52 set ylabel "Drain current Id (mA)"
54 set label "-0.5 Vp" at 4.1,0.625
55 set label "-0.25 Vp" at 4.1,1.4
56 set label "0" at 4.1,2.5
57 set label "Vg = 0.5 Vp" at 4.1,3.9
58 plot Vg=0.5*Vp,Id(Vd),Vg=0.25*Vp,Id(Vd),Vg=0,Id(Vd),Vg=-0.25*Vp,Id(Vd)
61 pause -1 "Hit return to continue"
63 # show off double axes
65 # amplitude frequency response
66 A(jw) = ({0,1}*jw/({0,1}*jw+p1)) * (1/(1+{0,1}*jw/p2))
75 set key bottom center box
76 set title "Amplitude and Phase Frequency Response"
77 set xlabel "jw (radians)"
78 set xrange [1.1 : 90000.0]
79 set x2range [1.1 : 90000.0]
80 set ylabel "magnitude of A(jw)"
81 set y2label "Phase of A(jw) (degrees)"
87 plot abs(A(jw)), 180/pi*arg(A(jw)) axes x2y2
89 pause -1 "Hit return to continue"
91 # undo what we've done