#from the given question:
Vcc=20 #in volts
Rb=1 #base resistance in Kohm
B=25 #gain
Rc=20 #collector resistance in ohm
#calculation of Q-point Parameters:
Ibq=(Vcc-0.7)/Rb #base current
Icq=B*Ibq #collector current
Vce=Vcc-Icq*Rc #collector -emitter voltage
#when applying ac signal:
Ib=10 #peak base current value in mA
Ic=B*Ib #peak collector current in mA
Ic=Ic*(10**-3) #converting Ic to ampere
Po=(Ic*Ic*Rc)/2 #output ac power in watt
Pi=Vcc*(Icq*(10**-3)) #input dc power in watt
n=(Po/Pi)*100 #efficiency in %
print "Input dc power Pi=",Pi,"W"
print "output ac power Po=",Po,"W"
print "Efficiency n=",round(n,1),"%"
#for the given transformer:
N1=15.0 #no. of turns in primary coil
N2=1.0 #no. of turns in secondary coil
Rl=8.0 #load resistance
#as seen looking into the primary coil of the transformer:
a=N1/N2
Rle=a*a*Rl
print "effective resistance Rl=",(Rle/1000),"Kohm"
import math
#for the given transformer:
Rl=16.0 #load resistance in ohm
Rle=10*(10**3) #effective load resistance in ohm
#as seen looking into the primary coil of the transformer:
x=Rle/Rl
Tr=math.sqrt(x)
print "Turn ratio =",int(Tr),": 1 "
#from the given Question:
Vcc=10 #supply voltage in volts
Icq=140*(10**-3) #collector current in ampere
Po=0.477 #output ac power in watt
#input dc power Pi:
Pi=Vcc*Icq #in watt
#power dissipiated Pq:
Pq=Pi-Po #in watt
#efficiency n:
n=(Po/Pi)*100 #in %
print "DC input power Pi=",Pi,"W"
print "power dissipiated by the transistor Pq=",Pq,"W"
print "Efficiency n=",round(n,1),"%"
#for the transformer-coupled class A amplifier:
Vcc=12 #supply voltage in volts
Vce=Vcc #collector-emitter voltage
Vp=12 #output voltage in volts
Vcemax=Vce+Vp #maximum value of Vce
Vcemin=Vce-Vp #minimum value of Vce
x=(Vcemax-Vcemin)/(Vcemax+Vcemin)
n=50*(x*x)
print "Efficiency of the amplifier n=",n,"%"
#for the transformer-coupled class A amplifier:
Vcc=12 #supply voltage in volts
Vce=Vcc #collector-emitter voltage
Vp=6.0 #output voltage in volts
Vcemax=Vce+Vp #maximum value of Vce
Vcemin=Vce-Vp #minimum value of Vce
x=((Vcemax-Vcemin)/(Vcemax+Vcemin))
n=50*x*x
print "Efficiency of the amplifier n=",n,"%"
#for the transformer-coupled class A amplifier:
Vcc=12 #supply voltage in volts
Vce=Vcc #collector-emitter voltage
Vp=2.0 #output voltage in volts
Vcemax=Vce+Vp #maximum value of Vce
Vcemin=Vce-Vp #minimum value of Vce
x=((Vcemax-Vcemin)/(Vcemax+Vcemin))
n=50*x*x
print "Efficiency of the amplifier n=",round(n,2),"%"
#for the transformer-coupled class B amplifier:
Vcc=30 #supply voltage in volts
Vp=20 #output voltage in volts
Rl=16.0 #load resistance in ohm
#calculation:
Ilp=Vp/Rl #peak load current in ampere
Idc=(2*Ilp)/3.14 #dc value of current drawn from power supply im ampere
Pi=Vcc*Idc #input dc power in watt
Po=(Vp*Vp)/(2*Rl) #output ac power in watt
n=(Po/Pi)*100 #efficiency in %
print "Input dc power Pi=",round(Pi,1),"W"
print "output ac power Po=",Po,"W"
print "Efficiency n=",round(n,1),"%"
#for the transformer-coupled class B amplifier:
Vcc=30 #supply voltage in volts
Rl=16.0 #load resistance in ohm
#calculation:
Po=(Vcc*Vcc)/(2*Rl) #output ac power in watt
Pi=(2*Vcc*Vcc)/(Rl*3.14) #input dc power in watt
n=(Po/Pi)*100 #efficiency in %
Pmax=(0.5*2*Vcc*Vcc)/(Rl*3.14*3.14) #maximum power dissipiated
print "DC input power Pi=",round(Pi,2),"W"
print "AC output power Po=",round(Po,3),"W"
print "maximum power dissipiated by each transistor Pmax=",round(Pmax,1),"W"
#for the transformer-coupled class B amplifier:
Vcc=24.0 #supply voltage in volts
Vp=22.0 #output voltage in volts
#calculation:
n=78.54*(Vp/Vcc) #efficiency in %
print "Efficiency n=",round(n,1),"%"
#for the transformer-coupled class B amplifier:
Vcc=24.0 #supply voltage in volts
Vp=06.0 #output voltage in volts
#calculation:
n=78.54*(Vp/Vcc) #efficiency in %
print "Efficiency n=",round(n,1),"%"
import math
#for the given circuit:
Vrms=12 #supply volts in rms voltage
Vcc=25 #in volts
Rl=4.0 #load resistance in ohm
#Calculation:
Vi=math.sqrt(2)*Vrms #peak input voltage in volts
Vl=Vi #voltage across load as gain=1
Po=(Vl*Vl)/(2*Rl) #Output power across load in watt
Il=Vl/Rl #peak load current in ampere
Idc=(2*Il)/3.14 #dc current from supplies
Pi=Vcc*Idc #power supplied to circuit in watt
Pq=(Pi-Po)/2 #power dissipiated
n=(Po/Pi)*100 #efficiency in %
print "DC input power Pi=",round(Pi,2),"W"
print "AC output power Po=",round(Po,2),"W"
print "maximum power dissipiated by each transistor Pmax=",round(Pq,1),"W"
print "Efficiency n=",round(n,1),"%"
#for the given circuit:
Vrms=12 #supply volts in rms voltage
Vcc=25 #in volts
Rl=4.0 #load resistance in ohm
#Calculation:
Pi=(2*Vcc*Vcc)/(Rl*3.142) #Input power
Po=(Vcc*Vcc)/(2*Rl) #Output power in watt
n=(Po/Pi)*100 #efficiency in %
Pq=(Pi-Po) #power dissipiated
Vl=Vp #condition to achieve maximum power operation
print "DC input power Pi=",round(Pi,2),"W"
print "AC output power Po=",round(Po,3),"W"
print "maximum power dissipiated by each transistor Pmax=",round(Pq,1),"W"
print "Efficiency n=",round(n,1),"%"
#for the given circuit:
Vrms=12 #supply volts in rms voltage
Vcc=25 #in volts
Rl=4.0 #load resistance in ohm
#Calculation:
Pmax=(2*Vcc*Vcc)/(3.142*3.142*Rl) #maximum power dissipiated in watt
Vl=0.636*Vcc #input voltage for maximum power dissipiation in volts
print "maximum power dissipiated=",round(Pmax,2),"W"
print "Input voltage for maximum power dissipiated=",Vl,"V"
#for the given output signal:
A1=2.5 #fundamental amplitude in volts
A2=0.25 #second harmonic amplitude in volts
A3=0.1 #Third harmonic amplitude in volts
A4=0.05 #Fourth harmonic amplitude in volts
#calculating Harmonic Distortions:
D2=(A2/A1)*100
D3=(A3/A1)*100
D4=(A4/A1)*100
print " Second harmonic distortion D2=",D2,"%"
print " Third harmonic distortion D3=",D3,"%"
print " Fourth harmonic distortion D4=",D4,"%"
import math
#for the given output signal:
A1=2.5 #fundamental amplitude in volts
A2=0.25 #second harmonic amplitude in volts
A3=0.1 #Third harmonic amplitude in volts
A4=0.05 #Fourth harmonic amplitude in volts
#calculating Harmonic Distortions:
D2=(A2/A1)
D3=(A3/A1)
D4=(A4/A1)
THD=math.sqrt((D2*D2)+(D3*D3)+(D4*D4))*100
print "Total harmonic Distortion THD=",round(THD,2),"%"
Vcemin=1.0 #maximum value of collector emitter voltage in volts
Vcemax=22.0 #minimum value of collector emitter voltage in volts
Vceq=12.0 #collector emitter voltage in volts at Q-point
x=(Vcemax+Vcemin)/2.0 #temporary variable
D2=(abs(x-Vceq)/abs(Vcemax-Vcemin))*100 #in %
print "second harmonic distortion D2=",round(D2,2),"%"
Vcemin=4.0 #maximum value of collector emitter voltage in volts
Vcemax=20.0 #minimum value of collector emitter voltage in volts
Vceq=12.0 #collector emitter voltage in volts at Q-point
x=(Vcemax+Vcemin)/2.0 #temporary variable
D2=(abs(x-Vceq)/abs(Vcemax-Vcemin))*100 #in %
print "second harmonic distortion D2=",round(D2,2),"%"
#given the distortion reading:
D2=0.1 #second harmonic distortion
D3=0.02 #third harmonic distortion
D4=0.01 #fourth harmonic distortion
I1=4 #in ampere
Rc=8 # load resistance in ohm
#Calculation:
THD=math.sqrt((D2*D2)+(D3*D3)+(D4*D4)) #Total harmonic distortion
P1=(I1*I1*Rc)/2 #Fundamental power in watt
P=(1+THD*THD)*P1 #Total power in watt
print "Total harmonic distortion=",round(THD,2),"%"
print "Fundamental power P=",P1,"W"
print "Total power P=",round(P,2),"W"
#for the given silicon transistor:
T1=125 #temperature in degree celsius
T2=25 #temperature in degree celsius
Df=0.5 #derating factor in W/degree C
Pd=80 #powerdissipiation at 25 degree celsius
PdT1=Pd-(T1-T2)*Df #power dissipiation at T1=125 degree celsius
print "maximum dissipiation at 125 degreeC=",PdT1,"W"
#for the given silicon power transistor:
Tsa=1.5 #in degreeC/W (heat sink thermal resistance)
Tjc=0.5 #in degreeC/W (transistor thermal resistance)
Tcs=0.6 #in degreeC/W (insulator thermal resistance)
Tj=200 #maximum junction temperature in celsius
Ta=40 #ambient temperature in celsius
Pd=(Tj-Ta)/(Tjc+Tcs+Tsa)
print " maximum power dissipiation Pd=",round(Pd,2),"W"