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   "cells": [
    {
     "cell_type": "heading",
     "level": 1,
     "metadata": {},
     "source": [
      "Chapter 4 - Differential amplifiers"
     ]
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Exa 4.1 - page 317"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# Given data\n",
      "V_CC= 10 # in volt\n",
      "V_EE= -10 # in volt\n",
      "I= 1 # in mA\n",
      "I=I*10**-3 # in A\n",
      "R_C= 10 # in kohm\n",
      "R_C=R_C*10**3 # in kohm\n",
      "V_BE=0.7 # in volt\n",
      "\n",
      "i_C1= I/2 # in A\n",
      "i_C2= i_C1 # in A\n",
      "print \"Value of i_C1 = %0.2f mA\" %(i_C1*10**3)\n",
      "\n",
      "V_C1= V_CC-i_C1*R_C # in V\n",
      "# For V_cm=0 volt\n",
      "V_E= -0.7 # in volt\n",
      "V_CE1= V_C1-V_E # in volt\n",
      "print \"For V_cm =0, The value of V_CE1 = %0.2f Volt\" %(V_CE1)\n",
      "\n",
      "# For V_cm= -5 volt\n",
      "V_cm= -5 # in V\n",
      "V_B= V_cm # in V\n",
      "# From V_BE= V_B-V_E\n",
      "V_E= V_B-V_BE # in volt\n",
      "V_CE1= V_C1-V_E # in volt\n",
      "print \"For V_cm =-5V, The value of V_CE1 = %0.2f Volt\" %V_CE1\n",
      "\n",
      "# For V_cm= 5 volt\n",
      "V_cm= 5 # in V\n",
      "V_B= V_cm # in V\n",
      "V_E= V_B-V_BE # in volt\n",
      "V_CE1= V_C1-V_E # in volt\n",
      "print \"For V_cm =5V, The value of V_CE1 = %0.2f Volt\" %V_CE1"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Value of i_C1 = 0.50 mA\n",
        "For V_cm =0, The value of V_CE1 = 5.70 Volt\n",
        "For V_cm =-5V, The value of V_CE1 = 10.70 Volt\n",
        "For V_cm =5V, The value of V_CE1 = 0.70 Volt\n"
       ]
      }
     ],
     "prompt_number": 2
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Exa 4.2 - page 338"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from numpy import sqrt\n",
      "# Given data\n",
      "V_DD= 1.5 # in V\n",
      "V_SS= V_DD # in V\n",
      "KnWL= 4 # in mA/V**2\n",
      "KnWL=KnWL*10**-3 # in A/V**2\n",
      "Vt= 0.5 # in V\n",
      "I=0.4 # in mA\n",
      "I=I*10**-3 #in A\n",
      "R_D= 2.5 # in k\u03a9\n",
      "R_D= R_D*10**3 # in \u03a9\n",
      "\n",
      "# Part (a)\n",
      "print \"Part (a)\"\n",
      "V_OV= sqrt(I/KnWL) # in V\n",
      "V_GS= V_OV+Vt # in V\n",
      "print \"Value of V_OV = %0.2f Volt\" %V_OV\n",
      "print \"Value of V_GS = %0.2f Volt\" %V_GS\n",
      "\n",
      "# Part (b)\n",
      "print \"Part (b)\"\n",
      "V_CM= 0 # in volt\n",
      "V_S= -V_GS # in volt\n",
      "print \"Value of V_S = %0.2f Volt\" %V_S\n",
      "I=0.4 # in mw\n",
      "i_D1= I/2 # in mA\n",
      "print \"Value of i_D1 = %0.2f mA\" %i_D1\n",
      "i_D1=i_D1*10**-3 # in A\n",
      "V_D1= V_DD-i_D1*R_D # in V\n",
      "V_D2=V_D1 # in V\n",
      "print \"Value of V_D1 = %0.2f Volt\" %V_D1\n",
      "print \"Value of V_D2 = %0.2f Volt\" %V_D2\n",
      "\n",
      "\n",
      "# Part (c)\n",
      "print \"Part (c)\"\n",
      "V_CM=1 # in V\n",
      "V_GS= 0.82 # in V\n",
      "V_G= 1 # in V\n",
      "V_S= V_G-V_GS # in V\n",
      "print \"Value of V_S = %0.2f Volt\" %V_S\n",
      "i_D1= I/2 # in mA\n",
      "print \"Value of i_D1 = %0.2f mA\" %i_D1\n",
      "i_D1=i_D1*10**-3 # in A\n",
      "V_D1= V_DD-i_D1*R_D # in V\n",
      "V_D2=V_D1 # in V\n",
      "print \"Value of V_D1 = %0.2f Volt\" %V_D1\n",
      "print \"Value of V_D2 = %0.2f Volt\" %V_D2\n",
      "\n",
      "# Part (d)\n",
      "print \"Part (d)\"\n",
      "V_CM_max= Vt+V_DD-i_D1*R_D\n",
      "print \"Highest value of V_CM = %0.2f Volt\" %V_CM_max\n",
      "\n",
      "# Part (e)\n",
      "V_S= 0.4 # in V\n",
      "print \"Part (e)\"\n",
      "V_CM_min= -V_SS+V_S+Vt+V_OV # in V\n",
      "print \"Lowest value of V_CM = %0.2f Volt \" %V_CM_min\n",
      "V_Smin= V_CM_min-V_GS # in volt\n",
      "print \"Lowest value of V_S = %0.2f Volt\" %V_Smin"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Part (a)\n",
        "Value of V_OV = 0.32 Volt\n",
        "Value of V_GS = 0.82 Volt\n",
        "Part (b)\n",
        "Value of V_S = -0.82 Volt\n",
        "Value of i_D1 = 0.20 mA\n",
        "Value of V_D1 = 1.00 Volt\n",
        "Value of V_D2 = 1.00 Volt\n",
        "Part (c)\n",
        "Value of V_S = 0.18 Volt\n",
        "Value of i_D1 = 0.20 mA\n",
        "Value of V_D1 = 1.00 Volt\n",
        "Value of V_D2 = 1.00 Volt\n",
        "Part (d)\n",
        "Highest value of V_CM = 1.50 Volt\n",
        "Part (e)\n",
        "Lowest value of V_CM = -0.28 Volt \n",
        "Lowest value of V_S = -1.10 Volt\n"
       ]
      }
     ],
     "prompt_number": 3
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Exa 4.3 - page 341"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# Given data\n",
      "I= 0.4 # in mA\n",
      "unCox= 0.2 # in mA/V**2\n",
      "i_D= I/2 # in mA\n",
      "V_OV1= 0.2 # in V\n",
      "V_OV2= 0.3 # in V\n",
      "V_OV3= 0.4 # in V\n",
      "WbyL1= 2*i_D/(unCox*V_OV1**2) \n",
      "gm1= I/V_OV1 # in mA/V\n",
      "WbyL2= 2*i_D/(unCox*V_OV2**2) \n",
      "gm2= I/V_OV2 # in mA/V\n",
      "WbyL3= 2*i_D/(unCox*V_OV3**2) \n",
      "gm3= I/V_OV3 # in mA/V\n",
      "print \"Vov (in V)         \",V_OV1,\"             \",V_OV2,\"         \",V_OV3\n",
      "print \"W/L                \",WbyL1,\"            \",round(WbyL2,1),\"        \",WbyL3\n",
      "print \"gm(in mA/V)        \",gm1,\"             \",round(gm2,2),\"        \",gm3"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Vov (in V)          0.2               0.3           0.4\n",
        "W/L                 50.0              22.2          12.5\n",
        "gm(in mA/V)         2.0               1.33          1.0\n"
       ]
      }
     ],
     "prompt_number": 4
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Exa 4.4 - page 341"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# Given data\n",
      "V_A= 20 # in V\n",
      "R_D= 5 # in k\u03a9\n",
      "R_D= R_D*10**3 # in \u03a9\n",
      "I= 0.8 # in mA\n",
      "I=I*10**-3 # in A\n",
      "i_D= I/2 # in A\n",
      "unCox= 0.2 # mA/V**2\n",
      "unCox= unCox*10**-3 # in A/V**2\n",
      "WbyL= 100 \n",
      "# Formula i_D= 1/2*unCox*WbyL*V_OV**2\n",
      "V_OV= sqrt(2*i_D/(unCox*WbyL)) # in V\n",
      "print \"The value of V_OV = %0.2f Volts\" %V_OV\n",
      "gm= I/V_OV # in A/V \n",
      "print \"The value of gm = %0.f mA/V\" %(gm*10**3)\n",
      "r_o= V_A/i_D # in \u03a9\n",
      "print \"The value of r_o = %0.f k\u03a9\" %(r_o*10**-3)\n",
      "# Ad= v_o/v_id = gm*(R_D || r_o)\n",
      "Ad= gm*(R_D*r_o/(R_D+r_o))  # in V/V\n",
      "print \"Differential gain = %0.1f V/V  \" %Ad"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "The value of V_OV = 0.20 Volts\n",
        "The value of gm = 4 mA/V\n",
        "The value of r_o = 50 k\u03a9\n",
        "Differential gain = 18.2 V/V  \n"
       ]
      }
     ],
     "prompt_number": 5
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Exa 4.5 - page 342"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from __future__ import division\n",
      "from numpy import log10\n",
      "# Given data\n",
      "R_D= 5 # in k\u03a9\n",
      "R_D= R_D*10**3 # in \u03a9\n",
      "R_SS= 25 # in k\u03a9\n",
      "R_SS= R_SS*10**3 # in \u03a9\n",
      "I= 0.8 # in mA\n",
      "I=I*10**-3 # in A\n",
      "i_D= I/2 # in A\n",
      "unCox= 0.2 # mA/V**2\n",
      "unCox= unCox*10**-3 # in A/V**2\n",
      "WbyL= 100 \n",
      "# Formula i_D= 1/2*unCox*WbyL*V_OV**2\n",
      "V_OV= sqrt(2*i_D/(unCox*WbyL)) # in V\n",
      "gm= i_D/V_OV # in A/V \n",
      "\n",
      "# Part (a)\n",
      "Ad= 1/2*gm*R_D # in V/V\n",
      "print \"Differential gain = %0.f V/V\" %(Ad)\n",
      "Acm= -R_D/(2*R_SS) # in V/V\n",
      "print \"Common mode gain = %0.1f V/V\" %Acm\n",
      "CMRR= abs(Ad)/abs(Acm) \n",
      "CMRRindB= round(20*log10(CMRR)) # in dB\n",
      "print \"Common mode rejection ratio = %0.f dB\" %CMRRindB\n",
      "\n",
      "\n",
      "# Part (b)\n",
      "print \"Part (b) when output is taken differentially\"\n",
      "Ad= gm*R_D # in V/V\n",
      "print \"Differential gain = %0.f V/V\" %Ad\n",
      "Acm= 0 \n",
      "print \"Common mode gain = %0.1f V/V \"%Acm\n",
      "CMRRindB= 20*log10(Ad/Acm) # in dB\n",
      "print \"Common mode rejection ratio = %0.f dB\" %CMRRindB\n",
      "\n",
      "\n",
      "# Part (c)\n",
      "print \"Part (c) when output is taken differentially but the drain resistance have a 1% mismatch.\"\n",
      "Ad= gm*R_D # in V/V\n",
      "print \"Differential gain = %0.f V/V\" %Ad\n",
      "# delta_R_D= 1% of R_D\n",
      "delta_R_D= R_D*1.0/100 # in \u03a9 \n",
      "Acm= R_D/(2*R_SS)*delta_R_D/R_D # in V/V\n",
      "print \"Common mode gain = %0.3f V/V\" %Acm\n",
      "CMRRindB= 20*log10(abs(Ad)/abs(Acm)) # in dB\n",
      "print \"Common mode rejection ratio = %0.1f dB\" %CMRRindB\n",
      "\n",
      "# Note: In the book, there is putting wrong value of Ad (20 at place of 10)\n",
      "#to evaluate the value of CMRR in dB in part(c) , So the answer of CMRR in dB of Part (c) is wrong"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Differential gain = 5 V/V\n",
        "Common mode gain = -0.1 V/V\n",
        "Common mode rejection ratio = 34 dB\n",
        "Part (b) when output is taken differentially\n",
        "Differential gain = 10 V/V\n",
        "Common mode gain = 0.0 V/V \n",
        "Common mode rejection ratio = inf dB\n",
        "Part (c) when output is taken differentially but the drain resistance have a 1% mismatch.\n",
        "Differential gain = 10 V/V\n",
        "Common mode gain = 0.001 V/V\n",
        "Common mode rejection ratio = 80.0 dB\n"
       ]
      }
     ],
     "prompt_number": 10
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Exa 4.6 - page 343"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# Given data (From Exa 4.4)\n",
      "R_D= 5 # in k\u03a9\n",
      "R_D= R_D*10**3 # in \u03a9\n",
      "R_SS= 25 # in k\u03a9\n",
      "R_SS= R_SS*10**3 # in \u03a9\n",
      "I= 0.8 # in mA\n",
      "I=I*10**-3 # in A\n",
      "i_D= I/2 # in A\n",
      "unCox= 0.2 # mA/V**2\n",
      "unCox= unCox*10**-3 # in A/V**2\n",
      "WbyL= 100 \n",
      "# Formula i_D= 1/2*unCox*WbyL*V_OV**2\n",
      "V_OV= sqrt(2*i_D/(unCox*WbyL)) # in V\n",
      "gm= i_D/V_OV # in A/V \n",
      "# gm mismatch have a negligible effect on Ad\n",
      "Ad= gm*R_D # in V/V(approx) \n",
      "# delta_gm= 1% of gm\n",
      "delta_gm = gm*1/100 # in A/V\n",
      "Acm= R_D/(2*R_SS)*delta_gm/gm \n",
      "CMRRindB= 20*log10(Ad/Acm) \n",
      "print \"CMRR is %0.f dB\"%CMRRindB"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "CMRR is 80 dB\n"
       ]
      }
     ],
     "prompt_number": 7
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Exa 4.7 - page 344"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# Given data \n",
      "V_CM= 0 \n",
      "V_BE= -0.7 # in volt\n",
      "v_E= V_CM-V_BE # in volt\n",
      "print \"Value of v_E = %0.1f Volts\" %v_E\n",
      "\n",
      "I_E= (5-0.7)/10**3 # in A\n",
      "v_B1= 0.5 # in V\n",
      "v_B2= 0 # in V\n",
      "# Due to Q1 is off  therefore\n",
      "v_C1= -5 # in V\n",
      "v_C2= I_E*10**3-5 # in V\n",
      "print \"Value of v_C1 = %0.1f Volts\" %v_C1\n",
      "print \"Value of v_C2 = %0.1f Volts\" %v_C2"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Value of v_E = 0.7 Volts\n",
        "Value of v_C1 = -5.0 Volts\n",
        "Value of v_C2 = -0.7 Volts\n"
       ]
      }
     ],
     "prompt_number": 8
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Exa 4.8 - page 345"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from numpy import log\n",
      "# Given data \n",
      "iE1_by_I= 0.99   # as it is given that iE1= 0.99 *I\n",
      "VT= 0.025 # in volt\n",
      "# Formula iE1= I/(1+%e**(-vid/VT))\n",
      "# %e**(-vid/VT)= 1/iE1_by_I-1\n",
      "vid= log( 1/iE1_by_I-1)*(-VT) # in volt\n",
      "print \"Input differential signal = %0.1f mV\" %round(vid*10**3)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Input differential signal = 115.0 mV\n"
       ]
      }
     ],
     "prompt_number": 11
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Exa 4.9 - page 345"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# Given data \n",
      "Beta= 100 \n",
      "\n",
      "# Part (a)\n",
      "RE= 150 # in \u03a9\n",
      "VT= 25 # in mV\n",
      "VT= VT*10**-3 # in V\n",
      "IE= 0.5 # in mA\n",
      "IE=IE*10**-3 # in A\n",
      "re1= VT/IE #in \u03a9\n",
      "R_id= 2*(Beta+1)*(re1+RE) # in \u03a9\n",
      "R_id= round(R_id*10**-3) # in k\u03a9\n",
      "print \"(a) The input differential resistance = %0.1f k\u03a9\" %R_id\n",
      "\n",
      "# Part (b)\n",
      "RC=10 #in k\u03a9\n",
      "RC=RC*10**3 #in \u03a9\n",
      "Rsig= 5+5 # in k\u03a9\n",
      "VoltageGain1= R_id/(Rsig+R_id) #voltage gain from the signal source to the base of Q1 and Q2 in V/V\n",
      "VoltageGain2= 2*RC/(2*(re1+RE)) # voltage gain from the bases to the output in V/V\n",
      "Ad= VoltageGain1*VoltageGain2 #in V/V\n",
      "print \"(b) The overall differential voltage gain = %0.1f V/V\" %Ad\n",
      "\n",
      "# Part (c)\n",
      "delta_RC= 0.02*RC \n",
      "R_EE= 200 #in k\u03a9\n",
      "R_EE=R_EE*10**3 #in \u03a9\n",
      "Acm= RC/(2*R_EE)*delta_RC/RC #in V/V\n",
      "print \"(c) Common mode gain = %0.e V/V\" %Acm\n",
      "\n",
      "# Part (d)\n",
      "CMRRindB= 20*log10(Ad/Acm) # in dB\n",
      "print \"(d) CMRR = %.f dB\" %CMRRindB\n",
      "\n",
      "# Part (e)\n",
      "V_A= 100 # in V\n",
      "r_o= V_A/(IE) # in \u03a9\n",
      "# Ricm= (Beta+1)*(R_EE || r_o/2)\n",
      "Ricm= (Beta+1)*(R_EE*(r_o/2)/(R_EE+(r_o/2))) \n",
      "print \"(e) Input common mode resistance = %0.1f M\u03a9\" %(Ricm*10**-6)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "(a) The input differential resistance = 40.0 k\u03a9\n",
        "(b) The overall differential voltage gain = 40.0 V/V\n",
        "(c) Common mode gain = 5e-04 V/V\n",
        "(d) CMRR = 98 dB\n",
        "(e) Input common mode resistance = 6.7 M\u03a9\n"
       ]
      }
     ],
     "prompt_number": 12
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Exa 4.10 - page 347"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# Given data  \n",
      "delta_RDbyRD= 2/100 \n",
      "delta_WLbyWL= 2/100 \n",
      "delta_Vt= 2 #in mV\n",
      "delta_Vt= delta_Vt*10**-3 # in V\n",
      "#(From Exa 4.4)\n",
      "V_A= 20 # in V\n",
      "R_D= 5 # in k\u03a9\n",
      "R_D= R_D*10**3 # in \u03a9\n",
      "I= 0.8 # in mA\n",
      "I=I*10**-3 # in A\n",
      "i_D= I/2 # in A\n",
      "unCox= 0.2 # mA/V**2\n",
      "unCox= unCox*10**-3 # in A/V**2\n",
      "WbyL= 100 \n",
      "# Formula i_D= 1/2*unCox*WbyL*V_OV**2\n",
      "V_OV= sqrt(2*i_D/(unCox*WbyL)) # in V\n",
      "V_OS1= V_OV/2*delta_RDbyRD # in V\n",
      "\n",
      "# V_OS due to W/L ratio\n",
      "V_OS2= V_OV/2*delta_WLbyWL # in V\n",
      "\n",
      "# V_OS due to threshold voltage\n",
      "V_OS3= delta_Vt # in V\n",
      "# Total offset voltage\n",
      "V_OS= sqrt(V_OS1**2+V_OS2**2+V_OS3**2) # in V\n",
      "V_OS= V_OS*10**3 # in mV\n",
      "print \"Total offset voltage = %0.1f mV\" %V_OS"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Total offset voltage = 3.5 mV\n"
       ]
      }
     ],
     "prompt_number": 13
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Exa 4.11 - page 348"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# Given data \n",
      "WLn= 100 \n",
      "WLp= 200 \n",
      "unCox= 0.2 # mA/V**2\n",
      "unCox=unCox*10**-3 #in A/V**2\n",
      "RSS= 25 # in k\u03a9\n",
      "RSS= RSS*10**3 # in \u03a9\n",
      "I=0.8 # in mA\n",
      "I=I*10**-3 #in A\n",
      "V_A= 20 # in V\n",
      "i_D= I/2 # in A\n",
      "# Formula i_D= 1/2*unCox*WLn*V_OV**2\n",
      "V_OV= sqrt(2*i_D/(unCox*WLn)) # in V\n",
      "gm= I/V_OV # in A/V\n",
      "print \"Value of Gm = %0.1f mA/V\" %(gm*10**3)\n",
      "ro2= V_A/(I/2) # in ohm\n",
      "ro4= ro2 # in ohm\n",
      "Ro= ro2*ro4/(ro2+ro4) # in ohm\n",
      "print \"Value of Ro = %0.1f k\u03a9\" %(Ro*10**-3)\n",
      "Ad= gm*Ro # in V/V\n",
      "print \"Value  of Ad = %0.1f V/V\" %Ad\n",
      "# Finding the value of gm3\n",
      "upCox= 0.1 # mA/V**2\n",
      "upCox=upCox*10**-3 #in A/V**2\n",
      "# Formula i_D= 1/2*upCox*WLp*V_OV**2\n",
      "V_OV= sqrt(2*i_D/(upCox*WLp)) # in V\n",
      "gm3= I/V_OV # in A/V\n",
      "Acm= 1/(2*gm3*RSS) #in V/V\n",
      "print \"Value of |Acm| = %0.3f V/V\" %(abs(Acm))\n",
      "CMRRindB= 20*log10(abs(Ad)/abs(Acm)) #in dB\n",
      "print \"CMRR = %0.f dB\" %(round(CMRRindB))"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Value of Gm = 4.0 mA/V\n",
        "Value of Ro = 25.0 k\u03a9\n",
        "Value  of Ad = 100.0 V/V\n",
        "Value of |Acm| = 0.005 V/V\n",
        "CMRR = 86 dB\n"
       ]
      }
     ],
     "prompt_number": 14
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Exa 4.12 - page 349"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# Given data \n",
      "I=0.8 # in mA\n",
      "I=I*10**-3 #in A\n",
      "V_A= 100 # in V\n",
      "Beta=160 \n",
      "VT=25 # in mV\n",
      "VT= VT*10**-3 #in V\n",
      "gm= (I/2)/VT # in A/V\n",
      "Gm= gm # Short circuit trnsconductance in mA/V\n",
      "print \"The value of Gm = %0.1f mA/V\" %(Gm*10**3)\n",
      "ro2= V_A/(I/2) # in ohm\n",
      "ro4= ro2 # in ohm\n",
      "Ro= ro2*ro4/(ro2+ro4) # in ohm\n",
      "print \"The value of Ro = %0.1f k\u03a9\" %(Ro*10**-3)\n",
      "Ad= Gm*Ro # in V/V\n",
      "print \"Value  of Ad = %0.1f V/V\" %Ad\n",
      "r_pi= Beta/gm #in \u03a9\n",
      "Rid= 2*r_pi # in \u03a9\n",
      "print \"The value of Rid = %0.1f k\u03a9\" %(Rid*10**-3)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "The value of Gm = 16.0 mA/V\n",
        "The value of Ro = 125.0 k\u03a9\n",
        "Value  of Ad = 2000.0 V/V\n",
        "The value of Rid = 20.0 k\u03a9\n"
       ]
      }
     ],
     "prompt_number": 15
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Exa 4.13 - page 349"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# Given data \n",
      "Vtp= -0.8 # in V\n",
      "KpWL= 3.5 # in mA/V**2\n",
      "I=0.7 # in mA\n",
      "I=I*10**-3 # in A\n",
      "R_D= 2 # in k\u03a9\n",
      "R_D=R_D*10**3 # in \u03a9\n",
      "KpWL=KpWL*10**-3 #in A/V**2\n",
      "v_G1= 0 # in V\n",
      "v_G2=v_G1 # in V\n",
      "VSS= 2.5 # in V\n",
      "VDD=VSS # in V\n",
      "VCS= 0.5 # in V\n",
      "print \"Part (a)\"\n",
      "V_OV= -sqrt(I/KpWL) # in V\n",
      "print \"The value of V_OV = %0.2f Volts\" %V_OV\n",
      "V_GS= V_OV+Vtp # in V\n",
      "print \"The value of V_GS = %0.2f Volts\" %V_GS\n",
      "V_G= 0 # as gate is connected ground\n",
      "v_S1= V_G-V_GS # in V\n",
      "v_S2= v_S1 # in V\n",
      "print \"The value of v_S1 = %0.2f Volts\" %v_S1\n",
      "v_D1= I/2*R_D-VDD # in V\n",
      "v_D2=v_D1 # in V\n",
      "print \"The value of v_D1 = %0.1f Volts\" %v_D1\n",
      "print \"The value of v_D2 = %0.1f Volts\" %v_D2\n",
      "\n",
      "print \"Part (b)\"\n",
      "V_CMmin= I*R_D/2-VDD+Vtp # in V\n",
      "V_CMmax= VSS-VCS+Vtp+V_OV # in V\n",
      "print \"The value of V_CMmin = %0.1f Volts\" %V_CMmin\n",
      "print \"The value of V_CMmax = %0.2f Volts\" %V_CMmax"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Part (a)\n",
        "The value of V_OV = -0.45 Volts\n",
        "The value of V_GS = -1.25 Volts\n",
        "The value of v_S1 = 1.25 Volts\n",
        "The value of v_D1 = -1.8 Volts\n",
        "The value of v_D2 = -1.8 Volts\n",
        "Part (b)\n",
        "The value of V_CMmin = -2.6 Volts\n",
        "The value of V_CMmax = 0.75 Volts\n"
       ]
      }
     ],
     "prompt_number": 16
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Exa 4.14 - page 351"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# Given data \n",
      "V_OV= 0.2 # in V\n",
      "gm=1 # in mA/V\n",
      "gm=gm*10**-3 # in A/V\n",
      "Vt=0.8 # in V\n",
      "unCox= 90 # in \u00b5A/V**2\n",
      "unCox=unCox*10**-6 # in A/V**2\n",
      "# gm= I/V_OV\n",
      "I= gm*V_OV # in A\n",
      "print \"Bias current = %0.1f mA\" %(I*10**3)\n",
      "I_D= I/2 # in A\n",
      "# Formula I_D= 1/2*unCox*WLn*V_OV**2\n",
      "WbyL= 2*I_D/(unCox*V_OV**2) \n",
      "print \"W/L ratio is %0.1f \"%WbyL"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Bias current = 0.2 mA\n",
        "W/L ratio is 55.6 \n"
       ]
      }
     ],
     "prompt_number": 17
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Exa 4.15 - page 351"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# Given data \n",
      "I=0.5 # in mA\n",
      "I=I*10**-3 # in A\n",
      "WbyL= 50 \n",
      "unCox= 250 # in \u00b5A/V**2\n",
      "unCox=unCox*10**-6 # in A/V**2\n",
      "V_A= 10 # in V\n",
      "R_D= 4 #in k\u03a9\n",
      "R_D= R_D*10**3 #in \u03a9\n",
      "V_OV= sqrt(I/(WbyL*unCox)) #in V\n",
      "print \"The value of V_OV = %0.2f V \" %V_OV\n",
      "gm= I/V_OV # in A/V\n",
      "print \"The value of gm = %0.2f mA/V\" %(gm*10**3)\n",
      "I_D=I/2 # in A\n",
      "ro= V_A/I_D # in \u03a9\n",
      "print \"The value of ro = %0.2f k\u03a9\" %(ro*10**-3)\n",
      "Ad= gm*(R_D*ro/(R_D+ro)) # in V/V\n",
      "print \"The value of Ad = %0.2f V/V \" %Ad"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "The value of V_OV = 0.20 V \n",
        "The value of gm = 2.50 mA/V\n",
        "The value of ro = 40.00 k\u03a9\n",
        "The value of Ad = 9.09 V/V \n"
       ]
      }
     ],
     "prompt_number": 18
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Exa 4.16 - page 352"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# Given data \n",
      "I=1 # in mA\n",
      "I=I*10**-3 # in A\n",
      "i_C=1 # in mA\n",
      "i_C=i_C*10**-3 # in A\n",
      "V_CC= 5 # in V\n",
      "V_CM= -2 # in V\n",
      "V_BE= 0.7 # in V\n",
      "R_C= 3 # in k\u03a9\n",
      "R_C= R_C*10**3 # in \u03a9\n",
      "Alpha=1 \n",
      "Beta=100 \n",
      "V_B= 1 # in V\n",
      "i_C1= Alpha*I # in A\n",
      "i_C2=0   # A\n",
      "v_E= V_B-V_BE # in V\n",
      "print \"Emitters voltage = %0.2f Volt\" %v_E,\n",
      "v_C1= V_CC-i_C1*R_C # in V\n",
      "v_C2= V_CC-i_C2*R_C # in V\n",
      "print \"Output voltage is\",v_C1,\"V &\",v_C2,\"V\""
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Emitters voltage = 0.30 Volt Output voltage is 2.0 V & 5 V\n"
       ]
      }
     ],
     "prompt_number": 19
    }
   ],
   "metadata": {}
  }
 ]
}