{ "metadata": { "name": "", "signature": "sha256:4d99941a24dd4b52b28be86bfd9badb4433db857a4af90f4e45a050680719b41" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter : 4 - Junction (Contd.)" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 4.12.1 - Page No : 4-46" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from __future__ import division\n", "from numpy import pi\n", "# Given data\n", "q = 1.6 * 10**-19 # in C\n", "N_D = 10**15 # in electrons/cm**3\n", "N_D = N_D * 10**6 # in electrons/m**3\n", "epsilon_r = 12 \n", "epsilon_o = (36 * pi * 10**9)**-1 \n", "epsilon = epsilon_o * epsilon_r \n", "a = 3 * 10**-4 # in cm\n", "a = a * 10**-2 # in m\n", "V_P = (q * N_D * a**2)/( 2 * epsilon) # in V\n", "print \"The Pinch off voltage = %0.1f V \" %V_P\n", "# V_GS = V_P * (1-(b/a))**2\n", "b = (1-0.707) *a # in m\n", "print \"The value of b = %0.3f \u00b5m \" %(b*10**6)\n", "print \"Hence the channel width has been reduced to about one third of its value for V_GS = 0\"\n", "# Note : The unit of b in the book is wrong since the value of b is calculated in \u00b5m." ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The Pinch off voltage = 6.8 V \n", "The value of b = 0.879 \u00b5m \n", "Hence the channel width has been reduced to about one third of its value for V_GS = 0\n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example : 4.12.2 - Page No : 4-47" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import sqrt\n", "# Given data\n", "I_DSS = 8 # in mA\n", "V_P = -4 # in V\n", "I_D = 3 # in mA\n", "V_GS = V_P * (1 - sqrt(I_D/I_DSS)) # in V\n", "print \"The value of V_GS = %0.2f V \" %V_GS\n", "V_DS = V_GS - V_P # in V\n", "print \"The value of V_DS = %0.2f V \" %V_DS" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The value of V_GS = -1.55 V \n", "The value of V_DS = 2.45 V \n" ] } ], "prompt_number": 4 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example : 4.12.3 - Page No : 4-47" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Given data\n", "V_P = -4 # in V\n", "I_DSS = 9 # in mA\n", "I_DSS = I_DSS * 10**-3 # in A\n", "V_GS = -2 # in V\n", "I_D = I_DSS * ((1 - (V_GS/V_P))**2) # in A\n", "print \"The drain current = %0.2f mA \" %(I_D*10**3)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The drain current = 2.25 mA \n" ] } ], "prompt_number": 5 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example : 4.12.4 - Page No : 4-47" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Given data\n", "I_DSS = 12 # in mA\n", "I_DSS = I_DSS * 10**-3 # in A\n", "V_P = -(6) # in V\n", "V_GS = -(1) # in V\n", "g_mo = (-2 * I_DSS)/V_P # in A/V\n", "g_m = g_mo * (1 - (V_GS/V_P)) # in S\n", "print \"The value of transconductance = %0.2f mS \" %(g_m*10**3)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The value of transconductance = 3.33 mS \n" ] } ], "prompt_number": 6 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 4.12.5 - Page No : 4-48" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Given data\n", "I_DSS = 10 # in mA \n", "I_DSS = I_DSS * 10**-3 # in A\n", "V_P = -(5) # in V\n", "V_GS = -(2.5) # in V\n", "g_m = ((-2 * I_DSS)/V_P) * (1 -(V_GS/V_P)) # in S\n", "g_m = g_m * 10**3 # in mS\n", "print \"The Transconductance = %0.f mS \" %g_m\n", "I_D = I_DSS * ((1 - (V_GS/V_P))**2) # in A\n", "print \"The drain current = %0.1f mA \" %(I_D*10**3)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The Transconductance = 2 mS \n", "The drain current = 2.5 mA \n" ] } ], "prompt_number": 8 } ], "metadata": {} } ] }