{ "metadata": { "name": "", "signature": "sha256:3dc67beaeaebdd84d2ec4524cdbfb840dc3f84ff2b897336112b72f4746f9690" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "CHAPTER07:BJT FUNDAMENTALS" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example E01 : Pg 342" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Ex_7_1\n", "#clc;\n", "#clear;\n", "#close;\n", "# given data : \n", "#format('v',6);\n", "alfa=0.90;# current gain\n", "ICO=15.;# micro A(reverse saturation currenrt)\n", "IE=4.;# mA(Emitter currenrt)\n", "IC=ICO*10.**-3.+alfa*IE;# mA\n", "IB=IE-IC;# mA\n", "IB=IB*1000.;# micro A\n", "print\"Collector Current(mA)\",IC\n", "print\"Base Current(micro A)\",IB" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Collector Current(mA) 3.615\n", "Base Current(micro A) 385.0\n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example E02 : Pg 342" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Ex_7_2\n", "#clc;\n", "#clear;\n", "#close;\n", "# given data : \n", "#format('v',6);\n", "Beta=90.;# unitless\n", "IC=4.;# mA(Collector Current)\n", "alfa=Beta/(1.+Beta);# current gain\n", "IB=IC/Beta;# mA(Base Current)\n", "IE=IC+IB;# mA(Emitter currenrt)\n", "print\"Value of alfa\",alfa\n", "print\"Base Current(micro A)\",IB*1000.\n", "print\"Emmiter Current(mA)\",IE" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Value of alfa 0.989010989011\n", "Base Current(micro A) 44.4444444444\n", "Emmiter Current(mA) 4.04444444444\n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example E03 : Pg 344" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Ex_7_3\n", "# given data : \n", "alfa=0.90;# current gain\n", "ICO=15.;# micro A(reverse saturation currenrt)\n", "IB=0.5;# /mA(Base Current)\n", "Beta=alfa/(1.-alfa);# unitless\n", "IC=Beta*IB+(1.+Beta)*ICO/1000.;# mA(Collector Current)\n", "print\"Collector Current(mA)\",IC" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Collector Current(mA) 4.65\n" ] } ], "prompt_number": 3 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example E04 : Pg 345" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Ex_7_4\n", "# given data : \n", "IB=20.;# /micro A(Base Current)\n", "IC=5.;# mA(Collector Current)\n", "Beta=IC*1000./IB;# unitless\n", "print\"Beta=\",Beta" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Beta= 250.0\n" ] } ], "prompt_number": 4 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example E05 : Pg 346" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Ex_7_5\n", "# given data : \n", "IB=50.;# /micro A(Base Current)\n", "IC=5.;# mA(Collector Current)\n", "IE=IC+IB/1000.;# mA\n", "Beta=IC*1000./IB;# unitless\n", "alfa=IC/IE;# current gain\n", "print\"Emitter Current(mA)\",IE\n", "print\"\\nBeta=\",Beta\n", "print\"\\nalfa=\",alfa\n", "print\"\\nVerify that alfa=Beta/(Beta+1)\"\n", "print alfa==Beta/(Beta+1);\n", "print\"\\nVerify that Beta=alfa/(1-alfa)\"\n", "print Beta==round(alfa/(1-alfa));" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Emitter Current(mA) 5.05\n", "\n", "Beta= 100.0\n", "\n", "alfa= 0.990099009901\n", "\n", "Verify that alfa=Beta/(Beta+1)\n", "True\n", "\n", "Verify that Beta=alfa/(1-alfa)\n", "True\n" ] } ], "prompt_number": 5 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example E06 : Pg 348" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Ex_7_6\n", "# given data : \n", "IE=10.;# mA\n", "IB=5.;# /mA(Base Current)\n", "IC=IE-IB;# mA(Collector Current)\n", "BetaR=IC/IB;# unitless\n", "alfaR=IC/IE;# current gain\n", "print \"BetaR=\",BetaR\n", "print \"alfaR=\",alfaR\n", "# Answer is wrong in the book." ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "BetaR= 1.0\n", "alfaR= 0.5\n" ] } ], "prompt_number": 6 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example E07 : Pg 348" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Ex_7_7\n", "# given data : \n", "Beta=100.;# unitless\n", "VBE=0.7;# V\n", "VCC=10.;# V\n", "# (a) VE=-0.7;# V\n", "print\"For the circuit in fig(a)\"\n", "VE=-0.7;# V(Constant voltage)\n", "R1=10.;# kohm\n", "R2=10.;# kohm\n", "IE=(VCC+VE)/R2;# mA\n", "IB=IE/(Beta+1.);# mA\n", "VC=VCC-R1*1000.*(IE-IB)/1000.;# V\n", "print\"Constant voltage fo the given transistor, VE(V)\",VE\n", "print\"Emitter current(mA)\",IE\n", "#format('v',5);\n", "IB=IB*1000;# /micro A\n", "print\"Base current(micro A)\",IB\n", "#format('v',6);\n", "print\"VC(V)\",VC\n", "# (b) VE=-0.7;# V\n", "R1=5.;# kohm\n", "R2=5.;# kohm\n", "VEE=-15.;# V\n", "print\"For the circuit in fig(b)\"\n", "VE=-0.7;# V(Constant voltage)\n", "R1=5.;# kohm\n", "R2=5.;# kohm\n", "IE=(VCC+VE)/R2;# mA\n", "IC=IE*Beta/(Beta+1.);# mA\n", "VC=VEE+R2*IC;# V\n", "print\"Constant voltage fo the given transistor, VE(V)\",VE\n", "print\"Emitter current(mA)\",IE\n", "print\"Base current(mA)\",IC\n", "#format('v',5);\n", "print\"VC(V)\",VC" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "For the circuit in fig(a)\n", "Constant voltage fo the given transistor, VE(V) -0.7\n", "Emitter current(mA) 0.93\n", "Base current(micro A) 9.20792079208\n", "VC(V) 0.792079207921\n", "For the circuit in fig(b)\n", "Constant voltage fo the given transistor, VE(V) -0.7\n", "Emitter current(mA) 1.86\n", "Base current(mA) 1.84158415842\n", "VC(V) -5.79207920792\n" ] } ], "prompt_number": 7 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example E08 : Pg 350" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Ex_7_8\n", "# given data : \n", "import math \n", "Beta=1.+0j;#math.inf;# Current gain\n", "VBE=0.7;# # V\n", "VB=0;# V(For large Beta)\n", "VE=VB-VBE;# # V\n", "print\"(a) Value of VB(V) : \",VB\n", "print\"(a) Value of VE(V) : \",VE\n", "# Part (b)\n", "R1=5.;# /kohm\n", "R2=5.;# /kohm\n", "VCC=10.;# /V\n", "VEE=-15.;# /V\n", "VE=VBE;# # V\n", "VC=VEE+R1/R2*(VCC-VBE);# V\n", "print\"(b) Value of VE(V) : \",VE\n", "print\"(b) Value of VC(V) : \",VC" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "(a) Value of VB(V) : 0\n", "(a) Value of VE(V) : -0.7\n", "(b) Value of VE(V) : 0.7\n", "(b) Value of VC(V) : -5.7\n" ] } ], "prompt_number": 8 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example E09 : Pg 351" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Ex_7_9\n", "# given data :\n", "VEE=5.;# # V\n", "VCC=-5.;# # V\n", "VE=1.;# # V\n", "RB=20.;# kohm\n", "RE=5.;# kohm\n", "RC=5.;# kohm\n", "VBE=0.7;# # V\n", "VB=VE-VBE;# /V\n", "IB=VB/RB;# /mA\n", "IE=(VEE-VE)/RE;# mA\n", "IC=IE-IB;# mA\n", "VC=VCC+IC*RC;# V\n", "Beta=IC/IB;# Current gain\n", "Alfa=IC/IE;# Current gain\n", "print\"VB(V) : \",VB\n", "print\"IB(mA) : \",IB\n", "print\"IE(mA) : \",IE\n", "print\"IC(mA) : \",IC\n", "#format('v',5);\n", "print\"Beta : \",Beta\n", "print\"Alfa : \",Alfa" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "VB(V) : 0.3\n", "IB(mA) : 0.015\n", "IE(mA) : 0.8\n", "IC(mA) : 0.785\n", "Beta : 52.3333333333\n", "Alfa : 0.98125\n" ] } ], "prompt_number": 9 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example E10 : Pg 351" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Ex_7_10\n", "#clc;\n", "#clear;\n", "#close;\n", "#format('v',6);\n", "# given data :\n", "delVB=0.4;# V\n", "delVC=0;# V# No change\n", "delVE=delVB;# V# Same change\n", "print\"delVE(V) : \",delVE\n", "print\"delVC(V) : \",delVC" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "delVE(V) : 0.4\n", "delVC(V) : 0\n" ] } ], "prompt_number": 10 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example E11 : Pg 352" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Ex_7_11\n", "# given data :\n", "VBE=0.7;# # V\n", "Beta=100.;# /Current Gain\n", "# Part (a)\n", "VCC=6.;# # V\n", "VEE=0;# # V\n", "VB=2.;# # V\n", "RE=18.;# kohm\n", "RC=3.;# kohm\n", "VE=VB-VBE;# V\n", "print\"(a) Emitter Voltage(V) : \",VE\n", "IE=1.;# /mA\n", "IC=IE*Beta/(1+Beta);# /mA\n", "VC=VCC-IC*RC;# V\n", "if VC>VE:\n", " print\"Circuit is in active mode.\"\n", "# Part (b)\n", "VEE=6.;# # V\n", "VCC=0;# # V\n", "VB=1.;# # V\n", "RE=10.;# kohm\n", "RC=10.;# kohm\n", "VE=VB+VBE;# V\n", "print\"(b) Emitter Voltage(V) : \",VE\n", "IE=(VEE-VE)/RE;# /mA\n", "IC=IE;# /mA(Assumed nearly equal)\n", "VC=VCC+IC*RC;# V\n", "if VC>VB :\n", " print\"Circuit is in saturation mode.\"\n", "# Part (c)\n", "VEE=9.5;# # V\n", "VCC=-50.;# # V\n", "VB=-5.;# # V\n", "RE=200.;# kohm\n", "RC=20.;# kohm\n", "VE=VB+VBE;# V\n", "print\"(c) Emitter Voltage(V) : \",VE\n", "IE=(VEE-VE)/RE;# /mA;# /mA\n", "IC=IE*Beta/(1+Beta);# /mA\n", "VC=VCC-IC*RC;# V\n", "if VC>VE :\n", " print\"Circuit is in active mode.\"\n", "else :\n", " print\"Circuit is in reverse active mode.\"\n", "# Part (d)\n", "VEE=-30.;# # V\n", "VCC=-10.;# # V\n", "VB=-20.;# # V\n", "RE=6.;# kohm\n", "RC=2.;# kohm\n", "VE=VB-VBE;# V\n", "print\"(d) Emitter Voltage(V) : \",VE\n", "IE=(VEE-VE)/RE;# /mA;# /mA\n", "IC=IE*Beta/(1.+Beta);# /mA\n", "VC=VCC-IC*RC;# V\n", "if VC>VE :\n", " print\"Circuit is in active mode.\"\n", "# Note : Printing error in part (a) in the textbook. Answer is also not accurate in the textbook for part(c)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "(a) Emitter Voltage(V) : 1.3\n", "Circuit is in active mode.\n", "(b) Emitter Voltage(V) : 1.7\n", "Circuit is in saturation mode.\n", "(c) Emitter Voltage(V) : -4.3\n", "Circuit is in reverse active mode.\n", "(d) Emitter Voltage(V) : -20.7\n", "Circuit is in active mode.\n" ] } ], "prompt_number": 11 } ], "metadata": {} } ] }