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|
{
"metadata": {
"name": ""
},
"nbformat": 3,
"nbformat_minor": 0,
"worksheets": [
{
"cells": [
{
"cell_type": "heading",
"level": 1,
"metadata": {},
"source": [
"Chapter 14: Solid State Electronics"
]
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 14.1, Page 718"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#Variable declaration\n",
"e = 1.6e-019; # Charge on an electron, C\n",
"mu_h = 0.048; # Mobility of holes, metre square/volt-s\n",
"mu_e = 0.135; # Mobility of electrons, metre square/volt-s \n",
"\n",
"#Calculations\n",
"# For P-type semiconductor\n",
"rho_p = 1e-01; # Resistivity of P type silicon, omh-m\n",
"# As rho_p = 1/(e*N_a*mu_h), solving for N_a\n",
"N_a = 1/(e*rho_p*mu_h); # Density of acceptor atoms, per metre cube\n",
"# For N-type semiconductor\n",
"rho_n = 1e-01; # Resistivity of N type silicon, omh-m\n",
"# As rho_n = 1/(e*N_d*mu_h), solving for N_d\n",
"N_d = 1/(e*rho_n*mu_e); # Density of donor atoms, per metre cube\n",
"\n",
"#Results\n",
"print \"Density of acceptor atoms = %4.2e per metre cube\"%N_a\n",
"print \"Density of donor atoms = %4.2e per metre cube\"%N_d #incorrect answer in textbook\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Density of acceptor atoms = 1.30e+21 per metre cube\n",
"Density of donor atoms = 4.63e+20 per metre cube\n"
]
}
],
"prompt_number": 1
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 14.2, Page 718"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#Variable declaration\n",
"e = 1.6e-019; # Charge on an electron, C\n",
"mu_e = 0.36; # Mobility of an electron, metre square/V-s\n",
"mu_h = 0.17; # Mobility of a hole, metre square/V-s\n",
"n_i = 2.5e+018; # Intrinsic concentration of Ge sample, per metre cube\n",
"\n",
"#Calculations\n",
"sigma = e*n_i*(mu_h+mu_e); # Electrical conductivity of Ge sample, mho per metre\n",
"rho = 1/sigma; # Electrical resistivity of Ge, ohm-m\n",
"\n",
"#Results\n",
"print \"The electrical conductivity of intrinsic germanium sample = %5.3f mho/m\"%sigma\n",
"print \"The electrical resistivity of intrinsic germanium sample = %3.1f ohm-m\"%rho\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The electrical conductivity of intrinsic germanium sample = 0.212 mho/m\n",
"The electrical resistivity of intrinsic germanium sample = 4.7 ohm-m\n"
]
}
],
"prompt_number": 2
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 14.3, Page 719"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#Variable declaration\n",
"e = 1.6e-019; # Charge on an electron, C\n",
"mu_e = 0.13; # Mobility of an electron, metre square/V-s\n",
"mu_h = 0.05; # Mobility of a hole, metre square/V-s\n",
"n_i = 1.5e+016; # Intrinsic concentration of Si, per metre cube\n",
"\n",
"#Calculations\n",
"# Pure Si\n",
"sigma = e*n_i*(mu_h+mu_e); # Electrical conductivity of Si, mho per metre\n",
"# Pure Si doped with donor impurity\n",
"n_e = 5e+028/1e+09; # Concentration of electrons, per metre cube\n",
"sigma_n = e*n_e*mu_e; # Electrical conductivity of Si doped with donor impurity, mho per metre\n",
"# Pure Si doped with acceptor impurity\n",
"n_h = 5e+028/1e+09; # Concentration of holes, per metre cube\n",
"sigma_p = e*n_h*mu_h; # Electrical conductivity of Si doped with acceptor impurity, mho per metre\n",
"\n",
"#Results\n",
"print \"The electrical conductivity of pure Si = %4.2e mho/m\"%sigma\n",
"print \"The electrical conductivity of Si doped with donor impurity = %4.2f mho/m\"%sigma_n\n",
"print \"The electrical conductivity of Si doped with acceptor impurity= %4.2f mho/m\"%sigma_p\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The electrical conductivity of pure Si = 4.32e-04 mho/m\n",
"The electrical conductivity of Si doped with donor impurity = 1.04 mho/m\n",
"The electrical conductivity of Si doped with acceptor impurity= 0.40 mho/m\n"
]
}
],
"prompt_number": 3
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 14.4, Page 720"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"from math import *\n",
"\n",
"#Variable declaration\n",
"Nd = 1; # For simplicity assume donor concentration to be unity, per metre cube\n",
"Nd_prime = 3*Nd; # Thrice the donor concentration, per metre cube\n",
"dE_CF1 = 0.5; # Energy difference between normal Fermi level and conduction level, eV\n",
"k_BT = 0.03; # Thermal energy at room temperature, eV\n",
"\n",
"#Calculations\n",
"# As Nd_prime/Nd = exp((dE_CF1 - dE_CF2))/k_BT, solving for dE_CF2\n",
"dE_CF2 = dE_CF1-k_BT*log(Nd_prime/Nd); # Energy difference between new postion of Fermi level and conduction level, eV\n",
"\n",
"#Result\n",
"print \"The new postion of Fermi level when donor concentration is trebled = %5.3f eV\"%dE_CF2\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The new postion of Fermi level when donor concentration is trebled = 0.467 eV\n"
]
}
],
"prompt_number": 5
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 14.5, Page 721"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"from math import *\n",
"\n",
"#Variable declaration\n",
"e = 1.6e-019; # Charge on an electron, C\n",
"T = 300; # Room temperature, K\n",
"J0 = 300e-03; # Saturation current density of the pn junction diode, A/metre square\n",
"J = 1e+05; # Forward current density of pn junction diode, A/metre square\n",
"k_B = 1.38e-023; # Boltzmann constant, J/K\n",
"eta = 1; # Ideality factor for Ge diode\n",
"\n",
"#Calculations\n",
"# As J = J0*exp(e*V/(eta*k_B*T)), solving for V\n",
"V = eta*k_B*T/e*log(J/J0); # Voltage required to cause a forward current density in pn junction diode, volt\n",
"\n",
"#Results\n",
"print \"The voltage required to cause a forward current density in pn junction diode = %5.3f V\"%V\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The voltage required to cause a forward current density in pn junction diode = 0.329 V\n"
]
}
],
"prompt_number": 6
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 14.6, Page 721"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"from math import *\n",
"\n",
"#Variable declaration\n",
"e = 1.6e-019; # Charge on an electron, C\n",
"T = 300; # Room temperature, K\n",
"J0 = 200e-03; # Saturation current density of the pn junction diode, A/metre square\n",
"J = 5e+04; # Forward current density of pn junction diode, A/metre square\n",
"k_B = 1.38e-023; # Boltzmann constant, J/K\n",
"eta = 1; # Ideality factor for Ge diode\n",
"\n",
"#Calculations\n",
"# As J = J0*exp(e*V/(eta*k_B*T)), solving for V\n",
"V = eta*k_B*T/e*log(J/J0); # Voltage required to cause a forward current density in pn junction diode, volt\n",
"\n",
"#Result\n",
"print \"The voltage required to cause a forward current density in pn junction diode = %5.3f V\"%V\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The voltage required to cause a forward current density in pn junction diode = 0.322 V\n"
]
}
],
"prompt_number": 7
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 14.7, Page 722"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"from math import *\n",
"\n",
"#Variable declaration\n",
"e = 1.6e-019; # Charge on an electron, C\n",
"T = 300; # Room temperature, K\n",
"J0 = 300e-03; # Saturation current density of the pn junction diode, A/metre square\n",
"J = 1e+05; # Forward current density of pn junction diode, A/metre square\n",
"k_B = 1.38e-023; # Boltzmann constant, J/K\n",
"eta = 2; # Ideality factor for Ge diode\n",
"\n",
"#Calculations\n",
"# As J = J0*exp(e*V/(eta*k_B*T)), solving for V\n",
"V = eta*k_B*T/e*log(J/J0); # Voltage required to cause a forward current density in pn junction diode, volt\n",
"\n",
"#Result\n",
"print \"The voltage required to cause a forward current density in Si iode = %5.3f V\"%V\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The voltage required to cause a forward current density in Si iode = 0.658 V\n"
]
}
],
"prompt_number": 8
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 14.8, Page 723"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#Variable declaration\n",
"I = 55e-03; # Forward current through Si diode, A\n",
"V = 3; # Forward bias across Si diode, V\n",
"eta = 2; # Ideality factor for Si diode\n",
"\n",
"#Calculations\n",
"R_dc = V/I; # Static diode resistance, ohm\n",
"R_ac = 0.026*eta/I; # Dynamic diode resistance, ohm\n",
"\n",
"#Results\n",
"print \"The static diode resistance = %4.1f ohm\"%R_dc\n",
"print \"The dynamic diode resistance = %5.3f ohm\"%R_ac\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The static diode resistance = 54.5 ohm\n",
"The dynamic diode resistance = 0.945 ohm\n"
]
}
],
"prompt_number": 9
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 14.9, Page 723"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"from math import *\n",
"\n",
"#Variable declaration\n",
"R_L = 1000; # Load resistance across HWR, ohm\n",
"V_rms = 200; # Rms value of voltage supply, V\n",
"\n",
"#Calculations\n",
"V0 = sqrt(2)*V_rms; # Peak value of voltage, V\n",
"I0 = V0/(R_L*1e-03); # Peak value of current, mA\n",
"I_dc = I0/pi; # Average value of current, mA\n",
"I_rms = I0/2; # Rms value of current, mA\n",
"V_dc = I_dc*R_L/1e+03; # Dc output voltage, V\n",
"PIV = V0; # Peak inverse voltage, V\n",
"\n",
"#Results\n",
"print \"The average value of current = %2d mA\"%I_dc\n",
"print \"The rms value of current = %5.1f mA\"%I_rms\n",
"print \"The dc output voltage = %2d V\"%(V_dc/1)\n",
"print \"PIV = %5.1f V\"%PIV\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The average value of current = 90 mA\n",
"The rms value of current = 141.4 mA\n",
"The dc output voltage = 90 V\n",
"PIV = 282.8 V\n"
]
}
],
"prompt_number": 10
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 14.10, Page 724"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"from math import *\n",
"\n",
"#Variable declaration\n",
"R_L = 980; # Load resistance across FWR, ohm\n",
"R_F = 20.; # Internal resistance of two crystal diodes in FWR, ohm\n",
"V_rms = 50; # Rms value of voltage supply, V\n",
"\n",
"#Calculations\n",
"V0 = sqrt(2)*V_rms; # Peak value of voltage, V\n",
"I0 = V0/((R_L+R_F)*1e-03); # Peak value of current, mA\n",
"I_dc = 2*I0/pi; # Average value of current, mA\n",
"I_rms = I0/sqrt(2); # Rms value of current, mA\n",
"V_dc = I_dc*R_L/1e+03; # Dc output voltage, V\n",
"eta = 81.2/(1+R_F/R_L); # Rectification efficiency\n",
"PIV = 2*V0; # Peak inverse voltage, V\n",
"\n",
"#Results\n",
"print \"The average value of current = %2d mA\"%I_dc\n",
"print \"The rms value of current = %2d mA\"%I_rms\n",
"print \"The dc output voltage = %4.1f V\"%(V_dc/1)\n",
"print \"The rectification efficiency = %4.1f percent\"%eta\n",
"print \"PIV = %5.1f V\"%PIV\n",
"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The average value of current = 45 mA\n",
"The rms value of current = 50 mA\n",
"The dc output voltage = 44.1 V\n",
"The rectification efficiency = 79.6 percent\n",
"PIV = 141.4 V\n"
]
}
],
"prompt_number": 17
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 14.11, Page 725"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#Variable declaration\n",
"delta_IC = 1e-03; # Change in collector current, A\n",
"delta_IB = 50e-06; # Change in base current, A\n",
"\n",
"#Calculations\n",
"bta = delta_IC/delta_IB; # Base current amplification factor\n",
"alpha = bta/(1+bta); # Emitter current amplification factor\n",
"\n",
"#Results\n",
"print \"Alpha of BJT = %4.2f\"%alpha\n",
"print \"Beta of BJT = %2d\"%bta\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Alpha of BJT = 0.95\n",
"Beta of BJT = 20\n"
]
}
],
"prompt_number": 12
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 14.12, Page 725"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#Variable declaration\n",
"I_E = 2; # Emitter current, mA\n",
"alpha = 0.88; # Emitter current amplification factor\n",
"\n",
"#Calculations\n",
"I_C = alpha*I_E; # Collector current, mA\n",
"I_B = I_E - I_C; # Base current of BJT in CB mode, mA\n",
"\n",
"#Result\n",
"print \"The base current of BJT in CB mode = %4.2f mA\"%I_B\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The base current of BJT in CB mode = 0.24 mA\n"
]
}
],
"prompt_number": 13
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 14.13, Page 725"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#Variable declaration\n",
"I_CBO = 12.5e-03; # Reverse saturation current, mA\n",
"I_E = 2; # Emitter current, mA\n",
"I_C = 1.97; # Collector current, mA\n",
"\n",
"#Calculations\n",
"# As I_C = alpha*I_E+I_CBO, solving for alpha\n",
"alpha = (I_C - I_CBO)/I_E; # Emitter current gain\n",
"I_B = I_E - I_C; # Base current, mA\n",
"\n",
"#Results\n",
"print \"The emitter current gain = %5.3f\"%alpha\n",
"print \"The base current = %4.2f mA\"%I_B\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The emitter current gain = 0.979\n",
"The base current = 0.03 mA\n"
]
}
],
"prompt_number": 14
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 14.14, Page 726"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#Variable declaration\n",
"alpha = 0.98; # Emitter current amplification factor\n",
"I_CBO = 5e-06; # Reverse saturation current, A\n",
"\n",
"#Calculations\n",
"bta = alpha/(1-alpha); # Emitter current amplification factor\n",
"I_CEO = 1/(1-alpha)*I_CBO; # Leakage current of BJT in CE mode, mA\n",
"\n",
"#Results\n",
"print \"The base current gain = %2g\"%bta\n",
"print \"The leakage current of BJT in CE mode = %4.2f mA\"%(I_CEO/1e-03)\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The base current gain = 49\n",
"The leakage current of BJT in CE mode = 0.25 mA\n"
]
}
],
"prompt_number": 15
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 14.15, Page 726"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#Variable declaration\n",
"R_i = 50; # Dynamic input resistance of PNP transistor, ohm\n",
"R_L = 5e+03; # Load resistance in collector circuit, ohm\n",
"alpha = 0.96; # Emitter current amplification factor\n",
"\n",
"#Calculations\n",
"A_v = alpha*R_L/R_i; # Voltage gain\n",
"A_p = alpha*A_v; # Power gain\n",
"\n",
"#Results\n",
"print \"The voltage gain = %2g\"%A_v\n",
"print \"The power gain = %2d\"%A_p\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The voltage gain = 96\n",
"The power gain = 92\n"
]
}
],
"prompt_number": 16
}
],
"metadata": {}
}
]
}
|