{ "metadata": { "name": "Chapter_5" }, "nbformat": 2, "worksheets": [ { "cells": [ { "cell_type": "markdown", "source": [ "

Chapter 5: Transistor Bias Circuits

" ] }, { "cell_type": "markdown", "source": [ "

Example 5.1, Page Number: 146

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "%pylab inline" ], "language": "python", "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "", "Welcome to pylab, a matplotlib-based Python environment [backend: module://IPython.zmq.pylab.backend_inline].", "For more information, type 'help(pylab)'." ] } ], "prompt_number": 1 }, { "cell_type": "code", "collapsed": false, "input": [ "", "# variable declaration", "V_BB=10.0; #voltage in volt", "V_CC=20.0; #voltage in volt", "B_DC=200.0; #B_DC value", "R_B=47.0*10**3; #resistance in ohm", "R_C=330.0; #resistance in ohm", "V_BE=0.7; #voltage in volt", "", "#current", "I_B=(V_BB-V_BE)/R_B; #base current", "I_C=B_DC*I_B; #Q POINT", "V_CE=V_CC-I_C*R_C; #Q POINT", "I_C_sat=V_CC/R_C; #saturation current", "I_c_peak=I_C_sat-I_C; #peak current ", "I_b_peak=I_c_peak/B_DC; #peak current in ampere", "", "#result", "print \"Q point of I_C = %.3f amperes\" %I_C", "print \"Q point of V_CE = %.2f volts\" %V_CE", "print \"peak base current = %.4f amperes\" %I_b_peak" ], "language": "python", "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Q point of I_C = 0.040 amperes", "Q point of V_CE = 6.94 volts", "peak base current = 0.0001 amperes" ] } ], "prompt_number": 2 }, { "cell_type": "markdown", "source": [ "

Example 5.2, Page Number: 149

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "", "# variable declaration", "B_DC=125.0; #DC value", "R_E=10.0**3; #resistance in ohm", "", "#calculation", "R_IN_base=B_DC*R_E; #base resistance", "", "#Result", "print \"DC input resistance, looking at base of transistor = %d ohm\" %R_IN_base" ], "language": "python", "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "DC input resistance, looking at base of transistor = 125000 ohm" ] } ], "prompt_number": 3 }, { "cell_type": "markdown", "source": [ "

Example 5.3, Page Number: 151

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "", "# variable declaration", "B_DC=100; #DC value", "R1=10*10**3; #resistance in ohm", "R2=5.6*10**3; #resistance in ohm", "R_C=1*10**3; #resistance in ohm", "R_E=560; #resistance in ohm", "V_CC=10; #voltage in volt", "V_BE=0.7 #voltage in volt", "", "#calculation", "R_IN_base=B_DC*R_E; #calculate base resistance", "#We can neglect R_IN_base as it is equal to 10*R2", "print \"input resistance seen from base = %d ohm\" %R_IN_base", "print \"which can be neglected as it is 10 times R2\"", "", "V_B=(R2/(R1+R2))*V_CC; #base voltage", "V_E=V_B-V_BE; #emitter voltage", "I_E=V_E/R_E; #emitter current", "I_C=I_E; #currents are equal", "V_CE=V_CC-I_C*(R_C+R_E); #voltage in volt", "", "#result", "print \"V_CE = %.2f volts\" %V_CE", "print \"I_C = %.3f amperes\" %I_C", "print \"Since V_CE>0V, transistor is not in saturation\"" ], "language": "python", "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "input resistance seen from base = 56000 ohm", "which can be neglected as it is 10 times R2", "V_CE = 1.95 volts", "I_C = 0.005 amperes", "Since V_CE>0V, transistor is not in saturation" ] } ], "prompt_number": 4 }, { "cell_type": "markdown", "source": [ "

Example 5.4, Page Number: 154

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "", "# variable declaration", "V_EE=10.0; #voltage in volt", "V_BE=0.7; #voltage in volt", "B_DC=150.0; #DC value ", "R1=22.0*10**3; #resistance in ohm", "R2=10.0*10**3; #resistance in ohm", "R_C=2.2*10**3; #resistance in ohm", "R_E=1.0*10**3; #resistance in ohm", "", "#calculation", "R_IN_base=B_DC*R_E; #R_IN_base>10*R2,so it can be neglected", "print \"input resistance as seen from base = %d ohm\" %R_IN_base", "print \"it can be neglected as it is greater than 10 times R2\"", "V_B=(R1/(R1+R2))*V_EE; #base voltage", "V_E=V_B+V_BE; #emitter voltage", "I_E=(V_EE-V_E)/R_E; #emitter current", "I_C=I_E; #currents are equal", "V_C=I_C*R_C; #collector voltage", "V_EC=V_E-V_C; #emitter-collector voltage", "", "#result", "print \"I_C collector current = %.4f amperes\" %I_C", "print \"V_EC emitter-collector voltage = %.2f Volts\" %V_EC" ], "language": "python", "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "input resistance as seen from base = 150000 ohm", "it can be neglected as it is greater than 10 times R2", "I_C collector current = 0.0024 amperes", "V_EC emitter-collector voltage = 2.24 Volts" ] } ], "prompt_number": 5 }, { "cell_type": "markdown", "source": [ "

Example 5.5, PAge Number: 154

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "", "# variable declaration", "R1=68.0*10**3; #resistance in ohm", "R2=47.0*10**3; #resistance in ohm", "R_C=1.8*10**3; #resistance in ohm", "R_E=2.2*10**3; #resistance in ohm", "V_CC=-6.0; #voltage in volt", "V_BE=0.7; #voltage in volt", "B_DC=75.0; #DC value", "", "#calculation", "R_IN_base=B_DC*R_E;", "print \"input resistance as seen from base\"", "print \"is not greater than 10 times R2 so it should be taken into account\"", "#R_IN_base in parallel with R2", "V_B=((R2*R_IN_base)/(R2+R_IN_base)/(R1+(R2*R_IN_base)/(R2+R_IN_base)))*V_CC;", "V_E=V_B+V_BE; #emitter voltage", "I_E=V_E/R_E; #emitter current", "I_C=I_E; #currents are equal", "V_C=V_CC-I_C*R_C; #collector voltage", "V_CE=V_C-V_E; #collector-emitter voltage", "", "#result", "print \"collector current = %.4f amperes\" %I_C", "print \"collector emitter voltage = %.2f volts\" %V_CE" ], "language": "python", "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "input resistance as seen from base", "is not greater than 10 times R2 so it should be taken into account", "collector current = -0.0006 amperes", "collector emitter voltage = -3.46 volts" ] } ], "prompt_number": 6 }, { "cell_type": "markdown", "source": [ "

Example 5.6, Page Number: 156

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "", "# variable declaration", "V_CC=12.0; #voltage in volt", "R_B=100.0*10**3; #resistance in ohm", "R_C=560.0; #resistance in ohm", "#FOR B_DC=85 AND V_BE=0.7V", "B_DC=85.0; #DC value", "V_BE=0.7; #base-emitter voltage", "", "#calculation", "I_C_1=B_DC*(V_CC-V_BE)/R_B; #collector current", "V_CE_1=V_CC-I_C_1*R_C; #collector-emittor voltage", "#FOR B_DC=100 AND V_BE=0.6V", "B_DC=100.0; #DC value ", "V_BE=0.6; #base emitter voltage", "I_C_2=B_DC*(V_CC-V_BE)/R_B; #collector current", "V_CE_2=V_CC-I_C_2*R_C; #voltage in volt", "p_del_I_C=((I_C_2-I_C_1)/I_C_1)*100; #percent change in collector current ", "p_del_V_CE=((V_CE_2-V_CE_1)/V_CE_1)*100; #percent change in C-E voltage", "", "#result", "print \"percent change in collector current = %.2f\" %p_del_I_C", "print \"percent change in collector emitter voltage = %.2f\" %p_del_V_CE" ], "language": "python", "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "percent change in collector current = 18.69", "percent change in collector emitter voltage = -15.18" ] } ], "prompt_number": 7 }, { "cell_type": "markdown", "source": [ "

Example 5.7, Page Number: 159

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "", "# variable declaration", "V_CC=20.0; #voltage in volt", "R_C=4.7*10**3; #resistance in ohm", "R_E=10.0*10**3; #resistance in ohm", "V_EE=-20.0; #voltage in volt", "R_B=100*10**3; #resistance in ohm", "#FOR B_DC=85 AND V_BE=0.7V", "B_DC=85; #DC value", "V_BE=0.7; #base-emitter voltage", "I_C_1=(-V_EE-V_BE)/(R_E+(R_B/B_DC));", "V_C=V_CC-I_C_1*R_C; #colector voltage", "I_E=I_C_1; #emittor current", "V_E=V_EE+I_E*R_E; #emittor voltage", "V_CE_1=V_C-V_E; #CE voltage", "print \"I_C_1 = %.3f\" %I_C_1", "print \"V_CE_1 = %.2f\" %V_CE_1", "#FOR B_DC=100 AND V_BE=0.6V", "B_DC=100; #DC value ", "V_BE=0.6; #base-emitter voltage", "I_C_2=(-V_EE-V_BE)/(R_E+(R_B/B_DC));", "V_C=V_CC-I_C_2*R_C;#colector voltage", "I_E=I_C_2; #emittor current", "V_E=V_EE+I_E*R_E; #emittor voltage", "V_CE_2=V_C-V_E; #CE voltage", "print \"I_C_2 = %.3f\" %I_C_2", "print \"V_CE_2 = %.2f\" %V_CE_2", "", "p_del_I_C=((I_C_2-I_C_1)/I_C_1)*100;", "p_del_V_CE=((V_CE_2-V_CE_1)/V_CE_1)*100;", "print \"percent change in collector currrent = %.2f\" %p_del_I_C", "print \"percent change in collector emitter voltage = %.2f\" %p_del_V_CE", "print \"answers in book are approximated\"" ], "language": "python", "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "I_C_1 = 0.002", "V_CE_1 = 14.61", "I_C_2 = 0.002", "V_CE_2 = 14.07", "percent change in collector currrent = 2.13", "percent change in collector emitter voltage = -3.69", "answers in book are approximated" ] } ], "prompt_number": 8 }, { "cell_type": "markdown", "source": [ "

Example 5.8, Page Number: 161

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "", "# variable declaratio", "V_CC=10.0; #voltage in volt", "B_DC=100.0; #Dc value", "R_C=10.0*10**3; #resistance in ohm", "R_B=100.0*10**3; #resistance in ohm", "V_BE=0.7; #base-emittor voltage", "", "#calculation", "I_C=(V_CC-V_BE)/(R_C+(R_B/B_DC)); #collector current", "V_CE=V_CC-I_C*R_C; #CE voltage", "", "#result", "print \"Q point of collector current %.4f amperes\" %I_C", "print \"Q point of collector-emitter voltage %.3f volts\" %V_CE" ], "language": "python", "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Q point of collector current 0.0008 amperes", "Q point of collector-emitter voltage 1.545 volts" ] } ], "prompt_number": 9 } ] } ] }