{
"metadata": {
"name": ""
},
"nbformat": 3,
"nbformat_minor": 0,
"worksheets": [
{
"cells": [
{
"cell_type": "heading",
"level": 1,
"metadata": {},
"source": [
"Chapter 11: Active Filters"
]
},
{
"cell_type": "heading",
"level": 3,
"metadata": {},
"source": [
"Example 11.1 Page No 298"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#Given\n",
"R=10 #Kohm\n",
"C=0.001 #microF\n",
"\n",
"#Calculation\n",
"wc=1/(R*10**3*C*10**-6)\n",
"fc=wc/(6.28)\n",
"\n",
"#Result\n",
"print\"The cut off frequency is\",round(fc/1000,2),\"Khz\"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The cut off frequency is 15.92 Khz\n"
]
}
],
"prompt_number": 1
},
{
"cell_type": "heading",
"level": 3,
"metadata": {},
"source": [
"Example 11.2 Page No 298"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#Given\n",
"f=2 #Frequency, khz\n",
"C=0.005 #MicroF\n",
"\n",
"#Calculation\n",
"R=1/(6.28*2*10**3*C*10**-6)\n",
"\n",
"#Result\n",
"print\"The value of R is\",round(R/1000,1),\"Kohm\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The value of R is 15.9 Kohm\n"
]
}
],
"prompt_number": 3
},
{
"cell_type": "heading",
"level": 3,
"metadata": {},
"source": [
"Example 11.3 Page No 298"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#Given\n",
"f=30 #rad/s, frequency\n",
"C=0.01 #microF\n",
"R=1/(f*10**3*C*10**-6)\n",
"\n",
"#Result\n",
"print\"The value of R is\",round(R/1000,1),\"Kohm\"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The value of R is 3.3 Kohm\n"
]
}
],
"prompt_number": 4
},
{
"cell_type": "heading",
"level": 3,
"metadata": {},
"source": [
"Example 11.4 Page No 301"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#Given\n",
"f=1 #Khz, cut off frequency\n",
"C1=0.01 #MicroF\n",
"\n",
"#Calculation\n",
"C2=2*C1\n",
"R=0.707/(6.28*f*10**3*C1*10**-6)\n",
"Rf=2*R\n",
"\n",
"#Result\n",
"print\"The value of R is\",round(R,0),\"ohm\"\n",
"print\"The value of Rf is\",round(Rf,0),\"ohm\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The value of R is 11258.0 ohm\n",
"The value of Rf is 22516.0 ohm\n"
]
}
],
"prompt_number": 5
},
{
"cell_type": "heading",
"level": 3,
"metadata": {},
"source": [
"Example 11.5 Page No 304"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#given\n",
"C3=0.01 #microF, from fig 11.5 (a)\n",
"f=1.0 #Khz, cut off frequency\n",
"\n",
"#Calculation\n",
"C1=C3/2.0\n",
"C2=2*C3\n",
"R=1/(6.28*f*10**3*C3*10**-6)\n",
"\n",
"#Result\n",
"print\"The value of C1=\",C1,\"microF\"\n",
"print\"The value of C2=\",C2,\"microF\"\n",
"print\"The value of R=\",round(R),\"ohm\"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The value of C1= 0.005 microF\n",
"The value of C2= 0.02 microF\n",
"The value of R= 15924.0 ohm\n"
]
}
],
"prompt_number": 9
},
{
"cell_type": "heading",
"level": 3,
"metadata": {},
"source": [
"Example 11.6 Page No 307"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#Given\n",
"C=0.002 #microF, capacitance\n",
"fc=10 #Khz, frequency\n",
"\n",
"#Calculation\n",
"R=1/(6.28*f*10**3*C*10**-6)\n",
"\n",
"#Result\n",
"print\"The value of R=\",round(R/10000),\"kohm\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The value of R= 8.0 kohm\n"
]
}
],
"prompt_number": 14
},
{
"cell_type": "heading",
"level": 3,
"metadata": {},
"source": [
"Example 11.7 Page No 307"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#Given\n",
"R=22.0 #kohm\n",
"C=0.001 #microF\n",
"\n",
"#Calculation\n",
"import math\n",
"wc=1/(R*10**3*C*10**-6)\n",
"fc=wc/(2*math.pi)\n",
"\n",
"#Result\n",
"print\"The value of wc is\",round(wc/10000,2),\"krad/s\"\n",
"print\"The value of fc is\",round(fc/10,1),\"Hz\"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The value of wc is 4.55 krad/s\n",
"The value of fc is 723.4 Hz\n"
]
}
],
"prompt_number": 28
},
{
"cell_type": "heading",
"level": 3,
"metadata": {},
"source": [
"Example 11.8 Page No 309"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#Given\n",
"C1=0.01 #microF\n",
"C2=C1\n",
"f=1 #KHz, frequency\n",
"\n",
"#Calculation\n",
"#From eq 11.9\n",
"R1=1.414/(6.28*f*10**3*C1*10**-6)\n",
"R2=R1/2.0\n",
"\n",
"#result\n",
"print\"The value of R1 is\",round(R1/1000,1),\"kohm\"\n",
"print\"The value of R2 is\",round(R2/1000,1),\"kohm\"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The value of R1 is 22.5 kohm\n",
"The value of R2 is 11.3 kohm\n"
]
}
],
"prompt_number": 31
},
{
"cell_type": "heading",
"level": 3,
"metadata": {},
"source": [
"Example 11.9 Page No 309"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#Given\n",
"C1=125 #pF\n",
"C2=C1 #KHz,cut off frequency\n",
"f=80 #Krad/s cutoff frequency\n",
"\n",
"#Calculation\n",
"#From eq 11.9\n",
"R1=1.414/(f*10**3*C1*10**-12)\n",
"R2=R1/2.0\n",
"\n",
"#result\n",
"print\"The value of R1 is\",round(R1/1000,0),\"kohm\"\n",
"print\"The value of R2 is\",round(R2/1000,1),\"kohm\"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The value of R1 is 141.0 kohm\n",
"The value of R2 is 70.7 kohm\n"
]
}
],
"prompt_number": 34
},
{
"cell_type": "heading",
"level": 3,
"metadata": {},
"source": [
"Example 11.10 Page No 311"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#Given\n",
"f=159.0 #Hz, cut off frequency\n",
"C=0.1 #microF\n",
"C1=C\n",
"C2=C\n",
"C3=C\n",
"wc=1\n",
"\n",
"#calculation\n",
"R3=1/(wc*10**3*C*10**-6)\n",
"R1=2*R3\n",
"R2=R3/2.0\n",
"\n",
"#Result\n",
"print\"(a)The value of R3 is\",round(R3/1000),\"kohm\"\n",
"print\"(b)The value of R1 is\",round(R1/1000),\"kohm\"\n",
"print\"(c)The value of R2 is\",round(R2/1000,0),\"kohm\"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"(a)The value of R3 is 10.0 kohm\n",
"(b)The value of R1 is 20.0 kohm\n",
"(c)The value of R2 is 5.0 kohm\n"
]
}
],
"prompt_number": 42
},
{
"cell_type": "heading",
"level": 3,
"metadata": {},
"source": [
"Example 11.11 Page No 311"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#Given\n",
"f=60 #kHz, cut off frequency\n",
"C=220 #pF\n",
"C1=C\n",
"C2=C\n",
"C3=C\n",
"\n",
"#calculation\n",
"R3=1/(6.28*f*10**3*C*10**-12)\n",
"R1=2*R3\n",
"R2=R3/2.0\n",
"\n",
"#Result\n",
"print\"(a)The value of R3 is\",round(R3/1000,0),\"kohm\"\n",
"print\"(b)The value of R1 is\",round(R1/1000),\"kohm\"\n",
"print\"(c)The value of R2 is\",round(R2/1000),\"kohm\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"(a)The value of R3 is 12.0 kohm\n",
"(b)The value of R1 is 24.0 kohm\n",
"(c)The value of R2 is 6.0 kohm\n"
]
}
],
"prompt_number": 46
},
{
"cell_type": "heading",
"level": 3,
"metadata": {},
"source": [
"Example 11.12 Page No 313"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#Given\n",
"f1=300 # Hz, lower cutoff frequency\n",
"f2=3000 #Hz, upper cutoff frequency\n",
"\n",
"#Calculation\n",
"import math\n",
"B=f2-f1\n",
"f=math.sqrt(f1*f2)\n",
"\n",
"#Result\n",
"print\"The bandwidth is\",B,\"Hz\"\n",
"print\"The frequency is\",round(f,1),\"Hz\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The bandwidth is 2700 Hz\n",
"The frequency is 948.7 Hz\n"
]
}
],
"prompt_number": 1
},
{
"cell_type": "heading",
"level": 3,
"metadata": {},
"source": [
"Example 11.13 Page No 314"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#Given\n",
"fr=950 #Hz, resonant frequency\n",
"B=2700 #Hz\n",
"\n",
"#Calculation\n",
"import math\n",
"fl=math.sqrt(B**2/4.0+fr**2)-B/2.0\n",
"fh=fl+B\n",
"\n",
"#Result\n",
"print\"The lower cutoff frequency is\",round(fl,1),\"Hz\"\n",
"print\"The upper cutoff frequency is\",round(fh,1),\"Hz\"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The lower cutoff frequency is 300.8 Hz\n",
"The upper cutoff frequency is 3000.8 Hz\n"
]
}
],
"prompt_number": 50
},
{
"cell_type": "heading",
"level": 3,
"metadata": {},
"source": [
"Example 11.14 Page No 314"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#Given\n",
"B=2700.0 #Hz\n",
"fr=950 #Hz resonant frequency\n",
"\n",
"#calculation\n",
"Q=fr/B\n",
"\n",
"#Result\n",
"print\"The quality factor\",round(Q,2)\n",
"\n",
"if Q<0.5:\n",
" print\"This filter is classified\"\n",
"else:\n",
" print\"This filter is not classified\"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The quality factor 0.35\n",
"This filter is classified\n"
]
}
],
"prompt_number": 55
},
{
"cell_type": "heading",
"level": 3,
"metadata": {},
"source": [
"Example 11.15 Page No 318"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#Given\n",
"fr=1000 #Hz, resonant frequency\n",
"fl=80 #From eq 11.16\n",
"fh=1280 #upper frequency\n",
"C=0.015 #microF\n",
"Q=2.0 #Quality factor\n",
"\n",
"#Calculation\n",
"import math\n",
"B=fr/Q\n",
"fl=math.sqrt(B**2/4.0+fr**2)-B/2.0\n",
"fh=fl+B\n",
"\n",
"R=0.1591/(B*C*10**-6)\n",
"Rr=R/(2*Q**2-1)\n",
"\n",
"#Result\n",
"print\"The Rr is\",round(Rr/1000,2),\"kohm\"\n",
"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The Rr is 3.03 kohm\n"
]
}
],
"prompt_number": 57
},
{
"cell_type": "heading",
"level": 3,
"metadata": {},
"source": [
"Example 11.16 Page No 319"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#Given\n",
"R=21.21*10**3 #ohm, resiatance\n",
"Rr=3.03*10**3 \n",
"C=0.015*10**-6 #F, capacitance\n",
"\n",
"#Calculation\n",
"import math\n",
"#From eq 11.12\n",
"fr=0.1125*math.sqrt(1+R/Rr)/(R*C)\n",
"B=0.1591/(R*C)\n",
"\n",
"#Result\n",
"print\"The resonant frequency is\",round(fr,0),\"Hz\"\n",
"print\"Bandwidth is\",round(B,0),\"Hz\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The resonant frequency is 1000.0 Hz\n",
"Bandwidth is 500.0 Hz\n"
]
}
],
"prompt_number": 2
},
{
"cell_type": "heading",
"level": 3,
"metadata": {},
"source": [
"Example 11.17 Page No 321"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#Given\n",
"fr=120 #Hz resonant frequency\n",
"B=12 #Hz\n",
"Q=10 #Quality factor\n",
"\n",
"#Calculation\n",
"C=0.33 #MicroF\n",
"R=0.1591/(B*C*10**-6)\n",
"Rr=R/(2*Q**2-1)\n",
"\n",
"#Result\n",
"print\"The value of resistance is\",round(R/1000,1),\"kohm\"\n",
"print\"The value of Rr is\",round(Rr,1),\"kohm\"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The value of resistance is 40.2 kohm\n",
"The value of Rr is 201.9 kohm\n"
]
}
],
"prompt_number": 64
}
],
"metadata": {}
}
]
}