{
"cells": [
 {
		   "cell_type": "markdown",
	   "metadata": {},
	   "source": [
       "# Chapter 5: Transistor Bias Circuits"
	   ]
	},
{
		   "cell_type": "markdown",
		   "metadata": {},
		   "source": [
			"## Example 5.1: DC_bias.sce"
		   ]
		  },
  {
"cell_type": "code",
	   "execution_count": null,
	   "metadata": {
	    "collapsed": true
	   },
	   "outputs": [],
"source": [
"//ex5.1\n",
"V_BB=10;\n",
"V_CC=20;\n",
"B_DC=200;\n",
"R_B=47*10^3;\n",
"R_C=330;\n",
"V_BE=0.7;\n",
"I_B=(V_BB-V_BE)/R_B;\n",
"I_C=B_DC*I_B;    //Q POINT\n",
"V_CE=V_CC-I_C*R_C;    //Q POINT\n",
"I_C_sat=V_CC/R_C;\n",
"I_c_peak=I_C_sat-I_C;\n",
"I_b_peak=I_c_peak/B_DC;\n",
"disp(I_C,'q point of I_C in amperes')\n",
"disp(V_CE,'Q point of V_CE in volts')\n",
"disp(I_b_peak,'peak base current in amperes')"
   ]
   }
,
{
		   "cell_type": "markdown",
		   "metadata": {},
		   "source": [
			"## Example 5.2: Input_resistance.sce"
		   ]
		  },
  {
"cell_type": "code",
	   "execution_count": null,
	   "metadata": {
	    "collapsed": true
	   },
	   "outputs": [],
"source": [
"//ex5.2\n",
"B_DC=125;\n",
"R_E=10^3;\n",
"R_IN_base=B_DC*R_E;\n",
"disp(R_IN_base,'DC input resistance in ohms, looking in at the base of transistor')"
   ]
   }
,
{
		   "cell_type": "markdown",
		   "metadata": {},
		   "source": [
			"## Example 5.3: Voltage_divider_bias.sce"
		   ]
		  },
  {
"cell_type": "code",
	   "execution_count": null,
	   "metadata": {
	    "collapsed": true
	   },
	   "outputs": [],
"source": [
"//ex5.3\n",
"B_DC=100;\n",
"R1=10*10^3;\n",
"R2=5.6*10^3;\n",
"R_C=1*10^3;\n",
"R_E=560;\n",
"V_CC=10;\n",
"V_BE=0.7\n",
"R_IN_base=B_DC*R_E;\n",
"//We can neglect R_IN_base as it is equal to 10*R2\n",
"disp(R_IN_base,'input resistance seen from base, which can be neglected as it is 10 times R2')\n",
"V_B=(R2/(R1+R2))*V_CC;\n",
"V_E=V_B-V_BE;\n",
"I_E=V_E/R_E;\n",
"I_C=I_E;\n",
"V_CE=V_CC-I_C*(R_C+R_E);\n",
"disp(V_CE,'V_CE in volts')\n",
"disp(I_C,'I_C in amperes')\n",
"disp('Since V_CE>0V, transistor is not in saturation')"
   ]
   }
,
{
		   "cell_type": "markdown",
		   "metadata": {},
		   "source": [
			"## Example 5.4: Voltage_bias_PNP.sce"
		   ]
		  },
  {
"cell_type": "code",
	   "execution_count": null,
	   "metadata": {
	    "collapsed": true
	   },
	   "outputs": [],
"source": [
"//ex5.4\n",
"V_EE=10;\n",
"V_BE=0.7;\n",
"B_DC=150;\n",
"R1=22*10^3;\n",
"R2=10*10^3;\n",
"R_C=2.2*10^3;\n",
"R_E=1*10^3;\n",
"R_IN_base=B_DC*R_E;    //R_IN_base>10*R2,so it can be neglected\n",
"disp(R_IN_base,'input resistance in ohms as seen from base. it can be neglected as it is greater than 10 times R2')\n",
"V_B=(R1/(R1+R2))*V_EE;\n",
"V_E=V_B+V_BE;\n",
"I_E=(V_EE-V_E)/R_E;\n",
"I_C=I_E;\n",
"V_C=I_C*R_C;\n",
"V_EC=V_E-V_C;\n",
"disp(I_C,'I_C collector current in amperes')\n",
"disp(V_EC,'V_EC emitter-collector voltage in Volts')"
   ]
   }
,
{
		   "cell_type": "markdown",
		   "metadata": {},
		   "source": [
			"## Example 5.5: PNP_Transistor.sce"
		   ]
		  },
  {
"cell_type": "code",
	   "execution_count": null,
	   "metadata": {
	    "collapsed": true
	   },
	   "outputs": [],
"source": [
"//ex5.5\n",
"R1=68*10^3;\n",
"R2=47*10^3;\n",
"R_C=1.8*10^3;\n",
"R_E=2.2*10^3;\n",
"V_CC=-6;\n",
"V_BE=0.7;\n",
"B_DC=75;\n",
"R_IN_base=B_DC*R_E;\n",
"disp('input resistance as seen from base is not greater than 10 times R2 so it should be taken into account')\n",
"//R_IN_base  in parallel with R2\n",
"V_B=((R2*R_IN_base)/(R2+R_IN_base)/(R1+(R2*R_IN_base)/(R2+R_IN_base)))*V_CC;\n",
"V_E=V_B+V_BE;\n",
"I_E=V_E/R_E;\n",
"I_C=I_E;\n",
"V_C=V_CC-I_C*R_C;\n",
"V_CE=V_C-V_E;\n",
"disp(I_C,'collector current in amperes')\n",
"disp(V_CE,'collector emitter voltage in volts')"
   ]
   }
,
{
		   "cell_type": "markdown",
		   "metadata": {},
		   "source": [
			"## Example 5.6: Qpoint_base_bias.sce"
		   ]
		  },
  {
"cell_type": "code",
	   "execution_count": null,
	   "metadata": {
	    "collapsed": true
	   },
	   "outputs": [],
"source": [
"//ex5.6\n",
"V_CC=12;\n",
"R_B=100*10^3;\n",
"R_C=560;\n",
"//FOR B_DC=85 AND V_BE=0.7V\n",
"B_DC=85;\n",
"V_BE=0.7;\n",
"I_C_1=B_DC*(V_CC-V_BE)/R_B;\n",
"V_CE_1=V_CC-I_C_1*R_C;\n",
"//FOR B_DC=100 AND V_BE=0.6V\n",
"B_DC=100;\n",
"V_BE=0.6;\n",
"I_C_2=B_DC*(V_CC-V_BE)/R_B;\n",
"V_CE_2=V_CC-I_C_2*R_C;\n",
"%_del_I_C=((I_C_2-I_C_1)/I_C_1)*100;\n",
"%_del_V_CE=((V_CE_2-V_CE_1)/V_CE_1)*100;\n",
"disp(%_del_I_C,'percent change in collector current')\n",
"disp(%_del_V_CE,'percent change in collector emitter voltage')"
   ]
   }
,
{
		   "cell_type": "markdown",
		   "metadata": {},
		   "source": [
			"## Example 5.7: Emitter_bias.sce"
		   ]
		  },
  {
"cell_type": "code",
	   "execution_count": null,
	   "metadata": {
	    "collapsed": true
	   },
	   "outputs": [],
"source": [
"//ex5.7\n",
"V_CC=20;\n",
"R_C=4.7*10^3;\n",
"R_E=10*10^3;\n",
"V_EE=-20;\n",
"R_B=100*10^3;\n",
"//FOR B_DC=85 AND V_BE=0.7V\n",
"B_DC=85;\n",
"V_BE=0.7;\n",
"I_C_1=(-V_EE-V_BE)/(R_E+(R_B/B_DC));\n",
"V_C=V_CC-I_C_1*R_C;\n",
"I_E=I_C_1;\n",
"V_E=V_EE+I_E*R_E;\n",
"V_CE_1=V_C-V_E;\n",
"disp(I_C_1)\n",
"disp(V_CE_1)\n",
"//FOR B_DC=100 AND V_BE=0.6V\n",
"B_DC=100;\n",
"V_BE=0.6;\n",
"I_C_2=(-V_EE-V_BE)/(R_E+(R_B/B_DC));\n",
"V_C=V_CC-I_C_2*R_C;\n",
"I_E=I_C_2;\n",
"V_E=V_EE+I_E*R_E;\n",
"V_CE_2=V_C-V_E;\n",
"disp(I_C_2)\n",
"disp(V_CE_2)\n",
"%_del_I_C=((I_C_2-I_C_1)/I_C_1)*100;\n",
"%_del_V_CE=((V_CE_2-V_CE_1)/V_CE_1)*100;\n",
"disp(%_del_I_C,'percent change in collector currrent')\n",
"disp(%_del_V_CE,'percent change in collector emitter voltage')\n",
"//plz note that the answers differ because of the number of places after the decimal that scilab generates"
   ]
   }
,
{
		   "cell_type": "markdown",
		   "metadata": {},
		   "source": [
			"## Example 5.8: Q_point.sce"
		   ]
		  },
  {
"cell_type": "code",
	   "execution_count": null,
	   "metadata": {
	    "collapsed": true
	   },
	   "outputs": [],
"source": [
"//ex5.8\n",
"V_CC=10;\n",
"B_DC=100;\n",
"R_C=10*10^3;\n",
"R_B=100*10^3;\n",
"V_BE=0.7;\n",
"I_C=(V_CC-V_BE)/(R_C+(R_B/B_DC));\n",
"V_CE=V_CC-I_C*R_C;\n",
"disp(I_C,'Q point of collector current in amperes')\n",
"disp(V_CE,'Q point of collector-emitter voltage in volts' )"
   ]
   }
],
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		   "display_name": "Scilab",
		   "language": "scilab",
		   "name": "scilab"
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		   "file_extension": ".sce",
		   "help_links": [
			{
			 "text": "MetaKernel Magics",
			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
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