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 "worksheets": [

  {

   "cells": [

    {

     "cell_type": "heading",

     "level": 1,

     "metadata": {},

     "source": [

      "Chapter8:AVALANCHE TRANSIT-TIME DEVICES"

     ]

    },

    {

     "cell_type": "heading",

     "level": 2,

     "metadata": {},

     "source": [

      "Eg8.2.1:pg-331"

     ]

    },

    {

     "cell_type": "code",

     "collapsed": false,

     "input": [

      "#(a)Calculate the maximum CW power\n",

      "n=0.15             #efficiency\n",

      "Vomax=100          #maximum operating voltage in volt\n",

      "Iomax=200*(10**-3) #maximum operating current in ampere\n",

      "Pdc=Vomax*Iomax \n",

      "P=n*Pdc \n",

      "print\"The maximum CW power(in Watts)is =\",int(P),\"W\"\n",

      "\n",

      "#(b) Calculate the resonant frequency\n",

      "L=6*(10**-6)      #drift-region Length in meter\n",

      "vd=2*(10**5)      #carrier drift velocity in m/s\n",

      "f=vd/(2*L) \n",

      "f=f/(10**9)  #in GHz\n",

      "print\"The resonant frequency(in GHz)is =\",round(f,2),\"GHz\""

     ],

     "language": "python",

     "metadata": {},

     "outputs": [

      {

       "output_type": "stream",

       "stream": "stdout",

       "text": [

        "The maximum CW power(in Watts)is = 3 W\n",

        "The resonant frequency(in GHz)is = 16.67 GHz\n"

       ]

      }

     ],

     "prompt_number": 1

    },

    {

     "cell_type": "heading",

     "level": 2,

     "metadata": {},

     "source": [

      "Eg8.3.1:pg-334"

     ]

    },

    {

     "cell_type": "code",

     "collapsed": false,

     "input": [

      "#calculate the avalanche-zone velocity\n",

      "J=20*(10**3)     #current density in A/cm**2\n",

      "q=1.6*(10**-19)  #charge of electron in C\n",

      "NA=2*(10**15)    #Doping Concentration in /cm**3\n",

      "vs=J/(q*NA) \n",

      "print\"Avalanche-zone velocity(in cm/s)is =\",\"{:.2e}\".format(vs),\"cm/s\"\n",

      "\n",

      "print('This means that the avalanch-zone velocity is much larger than the scattering-limited velocity') "

     ],

     "language": "python",

     "metadata": {},

     "outputs": [

      {

       "output_type": "stream",

       "stream": "stdout",

       "text": [

        "Avalanche-zone velocity(in cm/s)is = 6.25e+07 cm/s\n",

        "This means that the avalanch-zone velocity is much larger than the scattering-limited velocity\n"

       ]

      }

     ],

     "prompt_number": 2

    },

    {

     "cell_type": "heading",

     "level": 2,

     "metadata": {},

     "source": [

      "Eg8.4.1:pg-338"

     ]

    },

    {

     "cell_type": "code",

     "collapsed": false,

     "input": [

      "#(a) Calculate the break down voltage\n",

      "q=1.6*(10**-19)   #charge of electron\n",

      "N=2.8*(10**21)    #Donor Concentration /m**3\n",

      "L=6*(10**-6)      #silicon length in meter\n",

      "er=11.8           #Relative dielectric constant of silicon\n",

      "es=8.854*(10**-12)*er #permittivity of silicon in F/m\n",

      "Vbd=(q*N*(L**2))/es \n",

      "print\"The break down voltage(in Volts) is =\",round(Vbd,2),\"V\" \n",

      "\n",

      "#(b)Calculate the break down electric field\n",

      "Ebd=Vbd/L \n",

      "print\"the break down electric field is =\",\"{:.3e}\".format(Ebd),\"V/m =\",\"{:.3e}\".format(Ebd/100),\"V/cm\" "

     ],

     "language": "python",

     "metadata": {},

     "outputs": [

      {

       "output_type": "stream",

       "stream": "stdout",

       "text": [

        "The break down voltage(in Volts) is = 154.37 V\n",

        "the break down electric field is = 2.573e+07 V/m = 2.573e+05 V/cm\n"

       ]

      }

     ],

     "prompt_number": 3

    },

    {

     "cell_type": "heading",

     "level": 2,

     "metadata": {},

     "source": [

      "Eg8.5.1:pg-346"

     ]

    },

    {

     "cell_type": "code",

     "collapsed": false,

     "input": [

      "import math\n",

      "#(a)Calculate the power gain in decibels\n",

      "R=25             #R=f0/fs ,ratio of output frequency over signal frequency\n",

      "yQ=10            #figure of merit\n",

      "x=((yQ)**2)/R \n",

      "PG=(R*x)/((1+sqrt(1+x))**2) \n",

      "PG=10*math.log10(PG)  #calculating in dB\n",

      "print\"The power gain (in dB)is =\",round(PG,3),\"dB\" \n",

      "\n",

      "#(b)Calculate the noise figure in decibels\n",

      "\n",

      "Td=350          #Diode temperature in degree Kelvin\n",

      "To=300          #ambient Temperature in degree Kelvin\n",

      "F=1+(((2*Td)/To)*((1.0/yQ)+(1.0/yQ**2)))\n",

      "F=10*log10(F)   #calculating in dB\n",

      "print\"The noise figure (in dB)is =\",int(round(F)),\"dB\"\n",

      "\n",

      "#(c)Calculate the band width\n",

      "y=0.4            #factor of merit figure\n",

      "BW=2*y*sqrt(R)   #R=fo/fs\n",

      "print\"The band width is =\",int(BW)"

     ],

     "language": "python",

     "metadata": {},

     "outputs": [

      {

       "output_type": "stream",

       "stream": "stdout",

       "text": [

        "The power gain (in dB)is = 9.8 dB\n",

        "The noise figure (in dB)is = 1 dB\n",

        "The band width is = 4\n"

       ]

      }

     ],

     "prompt_number": 5

    }

   ],

   "metadata": {}

  }

 ]

}