# Chapter - 7 : SPECIAL PURPOSE DIODES AND OPTO ELECTRONIC DEVICES¶

## Ex 7.1 Pg 136¶

In [3]:
from __future__ import division
pzm=500*10**-3#
vz=6.8#
Izm=pzm/vz#
print "Izm=%0.2f"%(Izm*10**3),'mA'

Izm=73.53 mA


## Ex 7.2 Pg 137¶

In [4]:
from __future__ import division
pzm=500*10**-3#
d=3.33*10**-3#
a=75#
b=50#
Td=d*(a-b)#
print "Td=%0.2f"%(Td*10**3),"mW"
pz=pzm-Td #
print "pz=%0.2f"%(pz*10**3),'mW'

Td=83.25 mW
pz=416.75 mW


## Ex 7.3 Pg 138¶

In [5]:
from __future__ import division

IZ=10*10**-3#
vz=0.05#
rz=vz/IZ#
print "rz=%0.2f"%rz,"ohm"

rz=5.00 ohm


## Ex 7.4 Pg 139¶

In [6]:
from __future__ import division
Vz=4.7#
rz=15#
Iz=20*10**-3#
VZ1= Vz+(rz*Iz)#
print "VZ1=%0.2f"%VZ1,"V"

VZ1=5.00 V


## Ex 7.5 Pg 139¶

In [8]:
from __future__ import division
from math import sqrt,pi
C1=5*10**-12##min
C2=5*10**-12##min
L=10*10**-3#
CT=(C1*C2)/(C1+C2)##CTmax
print "CT=%0.2e"%CT,"F"
fo=1/(2*pi*sqrt(L*CT))#
print "fo=%0.2f"%(fo*10**-6),"MHz"
C1=50*10**-12##max
C2=50*10**-12##max
CT=(C1*C2)/(C1+C2)##CTmin
print "CT=%0.2e"%CT,"F"
fo=1/(2*pi*sqrt(L*CT))#
print "fo=%0.2f"%(fo*10**-3),"kHz"

CT=2.50e-12 F
fo=1.01 MHz
CT=2.50e-11 F
fo=318.31 kHz


## Ex 7.6 Pg 139¶

In [9]:
from __future__ import division
T=0.04*10**-6#
f=1/T#
print "f=%0.2f"%(f*10**-6),"MHz"
print "f=%0.2f"%(f*5*10**-6),"MHz"##frequency of 5th harmonic

f=25.00 MHz
f=125.00 MHz


## Ex 7.7 Pg 140¶

In [10]:
from __future__ import division

Vs=8#
VDmin=1.8#
VDmax=2#
Ifmax=16*10**-3#
Rs=(Vs-VDmin)/Ifmax#
print "Rs=%0.2f"%Rs,"ohm"
Rsmax=(Vs-VDmax)/Ifmax#
print "Rsmax=%0.2f"%Rsmax,"ohm"

Rs=387.50 ohm
Rsmax=375.00 ohm


## Ex 7.8 Pg 140¶

In [11]:
from __future__ import division

VDmin=1.5#
VDmax=2.3#
Vs=10#
R1=470#
Imax=(Vs-VDmin)/R1#
print "Imax=%0.2f"%(Imax*10**3),"mA"
Imin=(Vs-VDmax)/R1#
print "Imin=%0.2f"%(Imin*10**3),"mA"

Imax=18.09 mA
Imin=16.38 mA


## Ex 7.9 Pg 140¶

In [12]:
from __future__ import division

VDmin=1.8#
VDmax=3#
Vs1=24#
Rs1=820#
Vs2=5#
Rs2=120#
Imin=(Vs2-VDmax)/Rs2#
print "Imin=%0.2f"%(Imin*10**3),"mA"
Imax=(Vs1-VDmin)/Rs1#
print "Imax=%0.2f"%(Imax*10**3),"mA"
Imin=(Vs2-VDmax)/Rs2#
print "Imin=%0.2f"%(Imin*10**3),"mA"
Imax=(Vs2-VDmin)/Rs2#
print "Imax=%0.2f"%(Imax*10**3),"mA"

Imin=16.67 mA
Imax=27.07 mA
Imin=16.67 mA
Imax=26.67 mA


## Ex 7.10 Pg 141¶

In [13]:
from __future__ import division
r=1*10**3#
I=10*10**-3#
V=30#
#I=30/(R+r)
R=(V/I)-r##when dark
print "R=%0.2f"%(R*10**-3),"kohm"
R=100*10**3##when illuminated
Id=(V/(r+R))#
print "Id=%0.2f"%(Id*10**3),"mA"

R=2.00 kohm
Id=0.30 mA