{ "metadata": { "name": "" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter 08 : The Transistor at Low Frequency" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 8.2, Page No 251" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "Rl=10.0 #in K\n", "Rs=1.0 #in K\n", "hie=1.1 #in K\n", "hre=2.5*(10**-4) \n", "hfe=50.0\n", "hoe=25*(10**-3) #in K^-1\n", "\n", "#Calculations\n", "Ai= -hfe/(1+(hoe*Rl)) #Current Gain or Current Amplification\n", "print(\"Ai= %.2f \" %Ai)\n", "\n", "Ri = hie + (hre*Rl*Ai)\n", "print(\"Ri= %.2f K\" %Ri)\n", "\n", "Av=(Ai*Rl)/Ri #Voltage Gain\n", "print(\"Av= %.2f \" %Av)\n", "\n", "Avs=(Av*Ri)/(Ri+Rs) #Overall Voltage Gain taking source resistance into account\n", "print(\"Avs= %.2f \" %Avs)\n", "\n", "Ais=(Ai*Rs)/(Ri+Rs) #Overall current gain taking source resistance into account\n", "print(\"Ais= %.2f \" %Ais)\n", "\n", "#Results\n", "Yo=hoe-((hfe*hre)/(hie+Rs)) #Admittance\n", "print(\"Yo= %.2f K^-1 \" %Yo)\n", "\n", "Zo = 1.0/Yo #Impedence\n", "print(\"Zo= %.2f K \" %Zo)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Ai= -40.00 \n", "Ri= 1.00 K\n", "Av= -400.00 \n", "Avs= -200.00 \n", "Ais= -20.00 \n", "Yo= 0.02 K^-1 \n", "Zo= 52.50 K \n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 8.3, Page No 251" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#initialisation of variables\n", "\n", "#Yo = I/Vo\n", "#When current in a short circuit placed across the output terminals and V is the open circuit voltage\n", "print('When current in a short circuit placed across the output terminals and V is the open circuit voltage')\n", "print('I = -hf*I1=-(hf*Vs)/(Rs+hi)')\n", "#Applying KVL\n", "print('Vs = I1*(Rs+hi)+hr*V = -ho*V*(Rs+hi)/hf+hr*V')\n", "print('or')\n", "print('V = -(hf*Vs/(Rs+hi))/(ho-hf*hr(Rs+hi))')\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "When current in a short circuit placed across the output terminals and V is the open circuit voltage\n", "I = -hf*I1=-(hf*Vs)/(Rs+hi)\n", "Vs = I1*(Rs+hi)+hr*V = -ho*V*(Rs+hi)/hf+hr*V\n", "or\n", "V = -(hf*Vs/(Rs+hi))/(ho-hf*hr(Rs+hi))\n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 8.4 Page No 252" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#initialisation of variables\n", "\n", "hie=1.1#in K\n", "hre=2.5*(10^-4)\n", "hfe=50\n", "hoe=25*(10^-3)#in K^-1\n", "r=200#in K\n", "Rs=10#in K\n", "Ri=1#in K\n", "Rl=10#in K\n", "\n", "#Calculations\n", "rl=(r*Rs)/(r+Rs)#in K\n", "\n", "Ai = -hfe/(1+(hoe*rl))#Current Gain\n", "print(\"Ai = %.2f \" %Ai)\n", "\n", "Ri = hie + (hre*Ai*rl)\n", "print(\"Ri = %.2f K\" %Ri)\n", "\n", "Av=(Ai*rl)/Ri#Voltage Gain\n", "print(\"Av = %.2f \" %Av)\n", "\n", "k = r/(1-Av)\n", "ri = (Ri*k)/(Ri+k)\n", "print(\"ri = %.2f K\" %ri)\n", "\n", "\n", "#Results\n", "Avs = Av*(ri/(ri+Rs))#Overall voltage Gain taking Source resistance into account\n", "print(\"Avs = %.2f \" %Avs)\n", "\n", "ai = Avs*((ri+Rs)/Rl)\n", "print(\"ai = -I2/I1 = %.2f \" %ai)\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Ai = 0.00 \n", "Ri = 1.10 K\n", "Av = 0.00 \n", "ri = 1.09 K\n", "Avs = 0.00 \n", "ai = -I2/I1 = 0.00 \n" ] } ], "prompt_number": 3 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 8.5, Page No 254" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "\n", "hie = 2#in K\n", "hfe = 50\n", "hre = 6*(10^-4)\n", "hoe = 25*(10^-3)#in K^-1\n", "hic=2#in K\n", "hfc=-51\n", "hrc=1\n", "hoc=25*(10^-3)#/in K^-1\n", "Re2=5#in K\n", "Rs=1#in K\n", "Rc1=5#in K\n", "\n", "#The Second Stage\n", "\n", "#Calculations\n", "Rl = Re2\n", "Ai2 = -hfc/(1+(hoc*Re2))#Current Gain in @nd Transistor\n", "print(\"Ai2 = %.2f \" %Ai2)\n", "\n", "Ri2 = hic + (hrc*Ai2*Re2)\n", "print(\"Ri2 = %.2f K\" %Ri2)\n", "\n", "Av2 = (Ai2*Re2)/Ri2#Voltage Gain in 2nd Transistor\n", "print(\"Av2 = %.2f \" %Av2)\n", "\n", "#The First Stage\n", "\n", "Rl1 = (Rc1*Ri2)/(Rc1+Ri2)\n", "print(\"Rl1 = %.2f K\" %Rl1)\n", "\n", "\n", "Ai1 = -hfe/(1+(hoe*Rl1))#Current Gain in 1st Transistor\n", "print(\"Ai1 = %.2f \" %Ai1)\n", "\n", "Ri1 = hie + (hre*Ai1*Rl1)\n", "print(\"Ri1 = %.2f K\" %Ri1)\n", "\n", "Av1 = (Ai1*Rl1)/Ri1#Voltage Gain in 1st Transistor\n", "print(\"Av1 = %.2f \" %Av1)\n", "\n", "print('The output Admittance of Transistor')\n", "Yo1 = hoe - ((hfe*hre)/(hie+Rs))\n", "print(\"Yo= %.2f K^-1 \" %Yo)\n", "\n", "Ro1 = 1/Yo1\n", "\n", "#Output Impedence of First Stage\n", "print('Output Impedence of First Stage')\n", "ro1 = (Ro1*Rc1)/(Ro1+Rc1)\n", "print(\"ro1= %.2f K \" %ro1)\n", "rs2 = ro1\n", "\n", "Yo2 = hoc - ((hfc*hrc)/(hic+rs2))\n", "print(\"Yo2= %.2f K^-1 \" %Yo2)\n", "\n", "A1 = (Ai2*Ai2*Rc1)/(Ri2+Rc1)#Overall Current gain\n", "print(\"A1 = %.2f \" %A1)\n", "\n", "Av = Av2*Av1#Overall Voltage Gain\n", "print(\"Voltage Gain Av = %.2f \" %Av)\n", "print(Av,' = Av=')\n", "\n", "\n", "#Results\n", "Avs = (Av*Ri1)/(Ri1+Rs)#Overall Voltage gain with Source Impedence\n", "print(\"Overall Voltage gain taking Source Impedence into account = Avs = %.2f \" %Avs)\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Ai2 = -1.00 \n", "Ri2 = -3.00 K\n", "Av2 = 1.00 \n", "Rl1 = -8.00 K\n", "Ai1 = -1.00 \n", "Ri1 = -478.00 K\n", "Av1 = -1.00 \n", "The output Admittance of Transistor\n", "Yo= 0.02 K^-1 \n", "Output Impedence of First Stage\n", "ro1= 0.00 K \n", "Yo2= -199.00 K^-1 \n", "A1 = 2.00 \n", "Voltage Gain Av = -1.00 \n", "(-1, ' = Av=')\n", "Overall Voltage gain taking Source Impedence into account = Avs = -2.00 \n" ] } ], "prompt_number": 4 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 8.6 Page No 257" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "hie = 2#in K\n", "hfe = 50\n", "hre = 6*(10^-4)\n", "hoe = 25*(10^-3)#in K^-1\n", "hic=2#in K\n", "hfc=-51\n", "hrc=1\n", "hoc=25*(10^-3)#/in K^-1\n", "Re2=5#in K\n", "Rs=5#in K\n", "Rc1=5#in K\n", "\n", "#Calculations\n", "#For the CC output Stage\n", "print('For the CC output Stage')\n", "Rl = Re2\n", "Ai2 = 1+ hfe#Current gain in 2nd Transistor\n", "print(\"Ai2= %.2f \" %Ai2)\n", "Ri2 = hie+((1+hfe)*Rl)\n", "print(\"Ri2= %.2f K\" %Ri2)\n", "Av2=1-(hie/Ri2)#voltage gain in 2nd transistor\n", "print(\"Av2= %.2f \" %Av2)\n", "\n", "#For the CE input Stage\n", "print('For the CE input Stage')\n", "\n", "Ai1=-hfe#Current gain in 1st transistor\n", "Ri1 = hie\n", "print(\"Ai1= %.2f \" %Ai1)\n", "Rl1=(Rc1*Ri2)/(Rc1+Ri2)\n", "print(\"Rl1= %.2f K\" %Rl1)\n", "Av1=(Ai1*Rl1)/Ri1#Voltage gain in 1st transistor\n", "print(\"Av1= %.2f \" %Av1)\n", "ro1=Rc1\n", "Ro2 = (hie+Rs)/(1+hfe)\n", "ro2=(Ro2*Rl)/(Ro2+Rl)\n", "print(\"Effective Source Impedence = %.2f k\" %ro2)\n", "\n", "Av = Av1*Av2#Overall voltage gain\n", "\n", "#Results\n", "print(\"Overall Voltage Gain= %.2f k\" %Av)\n", "Ai = Ai1*Ai2*(Rc1/(Rc1+Ri2))#Overall current Gain\n", "print(\"Overall Current Gain= %.2f k\" %Ai)\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "For the CC output Stage\n", "Ai2= 51.00 \n", "Ri2= 257.00 K\n", "Av2= 1.00 \n", "For the CE input Stage\n", "Ai1= -50.00 \n", "Rl1= 4.00 K\n", "Av1= -100.00 \n", "Effective Source Impedence = 0.00 k\n", "Overall Voltage Gain= -100.00 k\n", "Overall Current Gain= 0.00 k\n" ] } ], "prompt_number": 5 } ], "metadata": {} } ] }