# Chapter - 8 : BIPOLAR JUNCTION TRANSISTORS¶

## Ex 8.1 Pg 161¶

In [2]:
from __future__ import division

#e.g 8.1
Ie=10*10**-3#
Ic=9.8*10**-3#
#Ie=Ib+Ic
Ib=Ie-Ic#
print "Ib=%0.2f"%(Ib*10**3),'mA'

Ib=0.20 mA


## Ex 8.2 Pg 161¶

In [5]:
from __future__ import division

Ie=6.28*10**-3#
Ic=6.20*10**-3#
a=Ic/Ie#
print "a=%0.4f"%a

a=0.9873


## Ex 8.3 Pg 161¶

In [7]:
from __future__ import division

#e.g8.3
a=0.967#
Ie=10*10**-3#
Ic=Ie*a##a=Ic/Ie
print "Ic=%0.2f"%(Ic*10**3),"mA"
Ib=Ie-Ic#
print "Ib=%0.2f"%(Ib*10**3),"mA"

Ic=9.67 mA
Ib=0.33 mA


## Ex 8.4 Pg 162¶

In [9]:
from __future__ import division

Ie=10*10**-3#
alpha=0.987#
Ic=Ie*alpha##alpha=Ic/Ie
print "Ic=%0.2f"%(Ic*10**3),"mA"
Ib=Ie-Ic#
print "Ib=%0.2f"%(Ib*10**3),"mA"

Ic=9.87 mA
Ib=0.13 mA


## Ex 8.5 Pg 163¶

In [10]:
from __future__ import division

alpha=0.975#
beta=200#
beta=(alpha/(1-alpha))#
print "beta=",beta
alpha=(beta/(1+beta))#
print "alpha=",alpha

beta= 39.0
alpha= 0.975


## Ex 8.6 Pg 163¶

In [11]:
from __future__ import division

BETA=100#
IC=40*10**-3#
IB=IC/BETA#
IE=IC+IB#
print "IE=%0.2f"%(IE*10**3),"mA"

IE=40.40 mA


## Ex 8.7 Pg 164¶

In [12]:
from __future__ import division
beta=150#
Ie=10*10**-3#
alpha=beta/(1+beta)
Ic=alpha*Ie##as alpha=(Ic/Ie)
print "Ic=%0.2f"%(Ic*10**3),"mA"
Ib=Ie-Ic##as  Ie=Ib+Ic
print "Ib=%0.2f"%(Ib*10**3),"mA"

Ic=9.93 mA
Ib=0.07 mA


## Ex 8.8 Pg 164¶

In [13]:
from __future__ import division
beta=170#
Ic=80*10**-3#
Ib=Ic/beta##beta=(Ic/Ib)
print "Ic=%0.2f"%(Ic*10**3),"mA"
Ie=Ic+Ib#
print "Ie=%0.2f"%(Ie*10**3),"mA"

Ic=80.00 mA
Ie=80.47 mA


## Ex 8.9 Pg 165¶

In [14]:
from __future__ import division
Ib=125*10**-6#
beta=200#
Ic=beta*Ib#
print "Ic=%0.2f"%(Ic*10**3),"mA"
Ie=Ic+Ib#
print "Ie=%0.2f"%(Ie*10**3),"mA"

Ic=25.00 mA
Ie=25.12 mA


## Ex 8.10 Pg 165¶

In [15]:
from __future__ import division
Ie=12*10**-3#
beta=140#
Ib=Ie/(1+beta)#
print "Ib=%0.2f"%(Ib*10**3),"mA"
Ic=Ie-Ib##as  Ie=Ib+Ic
print "Ic=%0.2f"%(Ic*10**3),"mA"

Ib=0.09 mA
Ic=11.91 mA


## Ex 8.11 Pg 165¶

In [17]:
from __future__ import division

IB=105*10**-6#
IC=2.05*10**-3#
BETA=IC/IB#
print "BETA=",BETA
ALPHA=BETA/(1+BETA)#
print "ALPHA=",ALPHA
IE=IC+IB#
print "IE=%0.2f"%(IE*10**3),"mA"
DELTA_IB=27*10**-6#
DELTA_IC=0.65*10**-3#
IBn=IB+DELTA_IB#
ICn=IC+DELTA_IC#
BETAn=ICn/IBn#
print "BETAn=",BETAn

BETA= 19.5238095238
ALPHA= 0.951276102088
IE=2.15 mA
BETAn= 20.4545454545


## Ex 8.12 Pg 166¶

In [18]:
from __future__ import division

#e.g 8.12
alpha=0.98#
Ico=5*10**-6#
Ib=100*10**-6#
Ic=((alpha*Ib)/(1-alpha))+(Ico/(1-alpha))#
print "Ic=%0.2f"%(Ic*10**3),"mA"
Ie=Ic+Ib#
print "Ie=%0.2f"%(Ie*10**3),"mA"

Ic=5.15 mA
Ie=5.25 mA


## Ex 8.13 Pg 166¶

In [19]:
from __future__ import division
Icbo=10*10**-6#
beta=50#
#Value of collector current when Ib=0.25*10**-3#
Ib=0.25*10**-3#
Ic=(beta*Ib)+(1+beta)*Icbo#
print "Ic=%0.2f"%(Ic*10**3),"mA"
#Value of new collector current if temperature rises to 50 degree
t1=27#
t2=50#
Icbo50=Icbo*2**((t2-t1)/10)#
print "Icbo50=%0.2f"%(Icbo50*10**6),"microA"
#collector current at 50 degree
Ic=beta*Ib+(1+beta)*Icbo50#
print "Ic=%0.2f"%(Ic*10**3),"mA"

Ic=13.01 mA
Icbo50=49.25 microA
Ic=15.01 mA