{ "metadata": { "name": "", "signature": "sha256:58dac3f9469c1fa78c6aeab36d8b7e58e74064bbe6f173699cbfdd2fb606b914" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter09:Power Amplifiers" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example E1 - Pg 327" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Determine the turns ratio of the transformer\n", "#given\n", "import math\n", "Rl=8.;#ohm\n", "Rl_=5.*10.**3.;#ohm\n", "TR=math.sqrt(Rl_/Rl); #Turns ratio\n", "print '%s %.f %s' %(\"Turns Ratio =\",TR,\": 1\");\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Turns Ratio = 25 : 1\n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example E2 - Pg 328" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Determine the output impedance of the transistor\n", "#given\n", "TR=16./1.; #turn ratio\n", "Rl=4.;#ohm #loudspeaker impedance\n", "ro=(TR**2.)*Rl;\n", "print '%s %.f %s' %(\"The output impedance of the transistor =\",ro,\"ohm\");\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The output impedance of the transistor = 1024 ohm\n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example E3 - Pg 334" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "#Determine the efficiency of a single ended transformer\n", "#given\n", "Vceq=10.;#V #supply voltage\n", "\n", "#At Vp=10V\n", "Vp=10.;#V\n", "Vce_max1=Vceq+Vp;\n", "Vce_min1=Vceq-Vp;\n", "n1=50.*((Vce_max1-Vce_min1)/(Vce_max1+Vce_min1))**2.;\n", "print '%s %.f %s' %(\"Efficiency (At Vp = 10V)=\",n1,\"percent\\n\");\n", "\n", "#At Vp=5V\n", "Vp=5.;#V\n", "Vce_max2=Vceq+Vp;\n", "Vce_min2=Vceq-Vp;\n", "n2=50.*((Vce_max2-Vce_min2)/(Vce_max2+Vce_min2))**2.;\n", "print '%s %.1f %s' %(\"Efficiency (At Vp = 5V)=\",n2,\"percent\\n\");\n", "\n", "#At Vp=1V\n", "Vp=1.;#V\n", "Vce_max3=Vceq+Vp;\n", "Vce_min3=Vceq-Vp;\n", "n3=50.*((Vce_max3-Vce_min3)/(Vce_max3+Vce_min3))**2.;\n", "print '%s %.1f %s' %(\"Efficiency (At Vp = 1V)=\",n3,\"percent\\n\");\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Efficiency (At Vp = 10V)= 50 percent\n", "\n", "Efficiency (At Vp = 5V)= 12.5 percent\n", "\n", "Efficiency (At Vp = 1V)= 0.5 percent\n", "\n" ] } ], "prompt_number": 3 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example E4 - Pg 336" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Determine input and output power and efficiency\n", "#given\n", "import math\n", "Vcc=20.;#V#supply voltage\n", "Rl=4.;#ohm\n", "Vp=15.;#V\n", "Ip=Vp/Rl;\n", "Idc=Ip/math.pi;\n", "Pi=Vcc*Idc;\n", "Po=((Vp/2.)**2.)/Rl;\n", "n=100.*Po/Pi;\n", "print '%s %.1f %s' %(\"Input power =\",Pi,\"W\\n\");\n", "print '%s %.2f %s' %(\"Output power =\",Po,\"W\\n\");\n", "print '%s %.2f %s' %(\"Efficiency =\",n,\"percent\\n\");\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Input power = 23.9 W\n", "\n", "Output power = 14.06 W\n", "\n", "Efficiency = 58.90 percent\n", "\n" ] } ], "prompt_number": 4 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example E5 - Pg 337" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Calculate the percentage increase in output power\n", "#given\n", "D=0.2;#harmonic distortion\n", "P=(1.+D**2.);#Total power increase\n", "\n", "#percent increase= (Pi*(1+D**2)-Pi)*100/Pi;\n", "#taking out and cancelling Pi\n", "PI=(P-1.)*100.;\n", "print '%s %.f %s' %(\"The percentage increase in output power=\",PI,\"percent\");\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The percentage increase in output power= 4 percent\n" ] } ], "prompt_number": 5 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example E6 - Pg 338" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Calculate harmonic distortion and percentage increase in output voltage due to this\n", "#given\n", "import math\n", "I1=60.;#A\n", "I2=6.;#A\n", "I3=1.2;#A\n", "I4=0.6;#A\n", "D2=I2/I1;\n", "D3=I3/I1;\n", "D4=I4/I1;\n", "print '%s %.f %s %s %.f %s %s %.f %s' %(\"The Harmonic distortion of each component \\nD2=\",D2*100,\"percent\\n\",\"\\nD3=\",D3*100,\"percent\\n\",\"\\nD4=\",D4*100,\"percent\\n\");\n", "D=math.sqrt((D2)**2.+(D3)**2.+(D4)**2.);\n", "print '%s %.f %s' %(\"The Total Harmonic distortion =\",D*100,\"percent\\n\");\n", "P=(1.+D**2.);#Total power increase\n", "#percent increase= (Pi*(1+D**2)-Pi)*100/Pi;\n", "#taking out and cancelling Pi\n", "PI=(P-1.)*100.;\n", "print '%s %.f %s' %(\"The percentage increase in output power =\",PI,\"percent\");\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The Harmonic distortion of each component \n", "D2= 10 percent\n", " \n", "D3= 2 percent\n", " \n", "D4= 1 percent\n", "\n", "The Total Harmonic distortion = 10 percent\n", "\n", "The percentage increase in output power = 1 percent\n" ] } ], "prompt_number": 6 } ], "metadata": {} } ] }