Chapter 14 : Operational Amlifiers

Pg: 632 Ex14.5

In [1]:
from __future__ import division
from math import log,log10
#initialisation of variables
ADOL= 10**5
ADOL1= 10
dc= 20
dc1= 10
f= 40 #kHz
#CALCULATIONS
ADOL2= dc*log(ADOL)
ADOL3= dc*log10(ADOL1)
f1= ADOL1*f
#RESULTS
print 'A0CL = %.f dB '%(ADOL3)
print '\n frequency = %.f kHz '%(f1)
A0CL = 20 dB 

 frequency = 400 kHz 

Pg: 633 Ex14.5

In [2]:
from __future__ import division
from math import pi
#initialisation of variables
SR= 0.5 #V/us
Vcon= 12 #V
#CALCULATIONS
f= SR*1000/(2*pi*Vcon)
#RESULTS
print 'full power = %.2f kHz '%f
full power = 6.63 kHz 

Pg: 634 Ex: 14.7

In [3]:
from __future__ import division
V_in=0#
I_B_max=100*10**-9#      #maximum bias current
I_os_max=40*10**-9#      #maximum offset current magnitude
V_os_max=2*10**-3#      #maximum offset voltage
R_1=10*10**3#
R_2=100*10**3#
#we approach in such a way to calculate output voltage due to each of dc sources and using superposition
#1)OFFSET-VOLTAGE
#As we place offset voltage at noninverting input
V_o_osV_max=-(1+(R_2/R_1))*(-V_os_max)#
V_o_osV_min=-(1+(R_2/R_1))*V_os_max#
#2)BIAS-CURRENT SOURCES
#assuming ideal opamp conditions
V_i=0#
I_1=0#
I_2=-I_B_max#
V_o_bias_max=-R_2*I_2-R_1*I_1#
V_o_bias_min=0#      #no minimum value of I_B is specified
#3)OFFSET-CURRENT SOURCE
#by analysis as in bias-current sources
V_o_osI_max=R_2*I_os_max/2#
V_o_osI_min=-R_2*I_os_max/2#

V_o_max=V_o_osV_max+V_o_bias_max+V_o_osI_max#      #maximum output volage
V_o_min=V_o_osV_min+V_o_bias_min+V_o_osI_min#      #minimum output voltage
print 'Maximum output voltage = %0.2f milli-volts'%(V_o_max*10**3)
print 'Minimum output voltage = %0.2f milli-volts'%(V_o_min*10**3)
Maximum output voltage = 34.00 milli-volts
Minimum output voltage = -24.00 milli-volts