Download - Clase2 Modelos Del Diodo
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Modelos del Diodo
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nodoCtodo(a) Smbolo del circuitoRegin de ruptura inversaRegin de polarizacin inversaRegin de polarizacin directa(b) Curva caracterstica tensin-corrienteMODELO REAL DEL DIODO
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MODELO REAL DEL DIODOVT, es el potencial trmico del diodo y es funcin de la constante de Boltzmann (K), la carga del electrn (q) y la temperatura absoluta del diodo T(K).
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Curva caracterstica de tensin-corriente para un diodo tpico de silicio de pequea seal a una temperatura de 3000 K. Tenga en cuenta los cambios de escala.
Codo0,6 V
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Anlisis de la lnea de carga
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Anlisis de la lnea de carga Punto BCurva caracterstica del diodoPunto de trabajoLnea de cargaPunto AEl intercepto x del load line es el voltaje de circuito abierto y el intercepto y es la corriente de corto circuito.
El quiescent point or Q-point (punto de operacin DC) es la interseccin de la caracterstica I-V del diodo con el load line.
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Aproximaciones o modelos del diodoEn el modelo del diodo ideal se equipara ste a un cortocircuito o a un circuito abierto, segn cmo est conectado.1 aproximacin: diodo ideal
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Anlisis usando el modelo ideal
Hacer una suposicin razonable del estado de cada diodo
Redibujar el circuito sustituyendo los diodos en conduccin por cortocircuitos y los diodos en corte por un circuito abierto.
Mediante el anlisis de circuitos determinar la corriente en cada diodo en conduccin y el voltaje en cada diodo abierto.
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Anlisis usando el modelo ideal (2) Comprobar las suposiciones hechas para cada diodo. Si hay contradiccin una corriente negativa en un diodo en conduccin, un voltaje positivo en un diodo en corte en cualquier lugar del circuito, entonces regresar al primer paso con una suposicin mejorada.
Cuando no hay contradicciones, las corrientes yvalores en el circuito se aproximan bastante a lasverdaderas.
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Ejemplo mtodo de estados asumidos
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Aproximacin lineal (2)Se considera que el diodo conduce sin resistencia por encima de la tensin umbral, y no conduce por debajo de la misma. Esto equivale a considerar un diodo como un interruptor o un diodo ideal en serie con una fuente de voltaje DC.VU= 0.3 V para el diodo de Ge VU= 0.7 V para el de Si.VI
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Aproximacin lineal (3)La 3 aproximacin es un diodo ideal con una resistencia en serie y una fuente de tensin.0,40,60,80,2VuV = Vu + IRdDVDIRd = V/I
DIODO
Curva caracterstica del diodo de unin
Ge
T300.0310.0320.0Vi-100
Vt (mV)25.85983966926.721834324627.58382898030
Io (mA)3.00E-048.76E-042.40E-03inc5.1719679338
e/k11.601
Ego (meV)780
V (mV)I (mA)
-105.1719679338
-100-1-0.0008550442-0.0023345127
-94.8280320662-1-0.0008506116-0.0023213356
-89.6560641324-0.95-0.0008452324-0.0023054409
-84.4840961986-0.9-0.0008387045-0.0022862682
-79.3121282648-0.8-0.0008307826-0.0022631415
-74.140160331-0.24-0.000821169-0.0022352455
-68.9681923972-0.154-0.0008095024-0.0022015964
-63.7962244634-0.084-0.0007953444-0.0021610078
-58.6242565296-0.036-0.000778163-0.0021120487
-53.4522885958-0.012-0.0007573126-0.0020529927
-48.280320662-0.000253624-0.0007320096-0.0019817576
-43.1083527282-0.0002433562-0.0007013031-0.0018958316
-37.9363847944-0.0002308151-0.0006640394-0.0017921851
-32.7644168606-0.0002154974-0.0006188181-0.0016671636
-27.5924489268-0.0001967883-0.0005639399-0.0015163588
-22.420480993-0.0001739369-0.0004973425-0.0013344535
-17.2485130592-0.0001460262-0.0004165234-0.0011150339
-12.0765451254-0.000111936-0.0003184455-0.0008503633
-6.9045771916-0.0000702981-0.0001994232-0.0005311096
-1.7326092578-0.0000194414-0.000054984-0.0001460162
3.4393586760.0000426750.00012029990.0003184952
8.61132660980.00011854420.00033301540.0008788028
13.78329454360.0002112110.00059115590.0015546629
18.95526247740.00032439460.00090442180.0023699057
24.12723041120.00046263720.0012845850.0033532763
29.2991983450.00063148720.00174593140.0045394476
34.47116627880.00083772110.00230579740.0059702433
39.64313421260.00108961560.00298522180.0076961124
44.81510214640.00139728040.00380973590.0097779079
49.98707008020.00177306290.00481032340.0122890326
55.1590380140.00223204480.00602458460.0153180272
60.33100594780.00279264650.00749814890.018971692
65.50297388160.0034773670.009286390.0233788531
70.67494181540.00431368640.01145650670.0286949042
75.84690974920.00533516930.01409004770.0351072857
81.0188776830.00658281140.01728597630.0428420943
86.19084561680.00810668480.02116438950.0521720545
91.36281355060.0099679480.02587103040.0634261346
96.53478148440.01224130.03158276560.0770011465
101.70674941820.01501797840.0385142310.0933757364
106.8787173520.0184094210.04692589780.1131272621
112.05068528580.02255173850.057133860.1369521499
117.22265321960.02761117640.06952171320.1656904503
122.39462115330.03379078780.0845549690.2003554575
127.56658908710.04133858230.10279854810.2421694378
132.73855702090.05055747920.12493800890.2926067257
137.91052495470.06181746540.15180530960.353445708
143.08249288850.07557044360.18441007150.4268315288
148.25446082230.0923683690.22397751850.5153517258
153.42642875610.11288540150.27199451890.6221274651
158.59839668990.13794496160.33026545870.7509235917
163.77036462370.16855277740.40098004730.9062813756
168.94233255750.20593724810.48679560231.0936786341
174.11430049130.25159874360.59093690651.3197228759
179.28626842510.30736982020.71731738881.5923842781
184.45823635890.3754887670.87068618371.9212767093
189.63020429270.45868943651.05680659412.3179967085
194.80217222650.56031096371.28267266552.7965323722
199.97414016030.68443177741.55677200853.3737565652
205.14610809410.83603328151.88940474684.0700218474
210.31807602791.02119977672.29307057614.9098780924
215.49004396171.24736264472.78293847845.9229381004
220.66201189551.52359859553.37741674317.1449217265
225.83397982931.86099394784.09884471478.6189153405
231.00594776312.27308956154.974332262710.3968910253
236.17791569692.77642428086.036778517712.5415390789
241.34988363073.39119869527.326108157415.1284784356
246.52185156454.14208586078.890771698518.248922941
251.69381949835.059221515610.789566174222.0128974952
256.86578743216.179413534113.093844612326.5531174604
262.03775536597.547619155215.890197344732.0296681215
267.20972329979.218749274519.283705904638.6356491913
272.381691233511.259872211523.401891787546.6039833849
277.553659167313.752905396528.399508462556.2156291267
282.725627101116.797903004934.464356708967.8094869672
287.897595034920.517071482341.824341806781.7943490019
293.069562968725.059674118650.756037776598.6633126221
298.241530902530.608021507961.5950804968119.0111668171
303.413498836337.384788312474.7487802522143.555364058
308.585466770145.661949978990.7114276668173.1613172177
313.757434703955.771698068110.0828681908208.8729134819
318.929402637768.1197722684133.5910431336251.9493211509
324.101370571583.2017441547162.1193442922303.9093871176
329.2733385053101.6229062151196.7398101078366.5851904486
334.4453064391124.1225643642238.7534107995442.1866403331
339.6172743729151.6037088851289.7389363116533.379396084
344.7892423067185.1692546004351.6123241894643.3788565987
349.9612102405226.1663047163426.6986568109776.0635332916
355.1331781743276.2402148042517.8195334901936.1118039531
360.3051461081337.4006266974628.39910072841129.1668693926
365.4771140419412.102122474762.59272502431362.0357291297
370.6490819757503.3427354542925.44314351861642.9291918927
375.8210499095614.78427180451123.06996031341981.7513835421
&A
Pgina &P
Caracterstica
-1
-1
-0.95
-0.9
-0.8
-0.24
-0.154
-0.084
-0.036
-0.012
-0.000253624
-0.0002433562
-0.0002308151
-0.0002154974
-0.0001967883
-0.0001739369
-0.0001460262
-0.000111936
-0.0000702981
-0.0000194414
0.000042675
0.0001185442
0.000211211
0.0003243946
0.0004626372
0.0006314872
0.0008377211
0.0010896156
0.0013972804
0.0017730629
0.0022320448
0.0027926465
0.003477367
0.0043136864
0.0053351693
0.0065828114
0.0081066848
0.009967948
0.0122413
0.0150179784
0.018409421
0.0225517385
0.0276111764
0.0337907878
0.0413385823
0.0505574792
0.0618174654
0.0755704436
0.092368369
0.1128854015
0.1379449616
0.1685527774
0.2059372481
0.2515987436
0.3073698202
0.375488767
0.4586894365
0.5603109637
0.6844317774
0.8360332815
1.0211997767
1.2473626447
1.5235985955
1.8609939478
2.2730895615
2.7764242808
3.3911986952
4.1420858607
5.0592215156
6.1794135341
7.5476191552
9.2187492745
11.2598722115
13.7529053965
16.7979030049
20.5170714823
25.0596741186
30.6080215079
37.3847883124
45.6619499789
55.771698068
68.1197722684
83.2017441547
101.6229062151
124.1225643642
151.6037088851
185.1692546004
226.1663047163
276.2402148042
337.4006266974
412.102122474
503.3427354542
614.7842718045
&A
Pgina &P
Io
V (V)
I (mA)
Caracterstica (2)
0.0150179784
0.018409421
0.0225517385
0.0276111764
0.0337907878
0.0413385823
0.0505574792
0.0618174654
0.0755704436
0.092368369
0.1128854015
0.1379449616
0.1685527774
0.2059372481
0.2515987436
0.3073698202
0.375488767
0.4586894365
0.5603109637
0.6844317774
0.8360332815
1.0211997767
1.2473626447
1.5235985955
1.8609939478
2.2730895615
2.7764242808
3.3911986952
4.1420858607
5.0592215156
6.1794135341
7.5476191552
9.2187492745
11.2598722115
13.7529053965
16.7979030049
20.5170714823
25.0596741186
30.6080215079
37.3847883124
45.6619499789
55.771698068
68.1197722684
83.2017441547
101.6229062151
124.1225643642
151.6037088851
185.1692546004
226.1663047163
276.2402148042
337.4006266974
412.102122474
503.3427354542
614.7842718045
&A
Pgina &P
Vcodo
V = Vcodo + IRd
V = e0+ IRd
V (mV)
I (mA)
Io=f(t)
-1-0.0008550442-0.0023345127
-1-0.0008506116-0.0023213356
-0.95-0.0008452324-0.0023054409
-0.9-0.0008387045-0.0022862682
-0.8-0.0008307826-0.0022631415
-0.24-0.000821169-0.0022352455
-0.154-0.0008095024-0.0022015964
-0.084-0.0007953444-0.0021610078
-0.036-0.000778163-0.0021120487
-0.012-0.0007573126-0.0020529927
-0.000253624-0.0007320096-0.0019817576
-0.0002433562-0.0007013031-0.0018958316
-0.0002308151-0.0006640394-0.0017921851
-0.0002154974-0.0006188181-0.0016671636
-0.0001967883-0.0005639399-0.0015163588
-0.0001739369-0.0004973425-0.0013344535
-0.0001460262-0.0004165234-0.0011150339
-0.000111936-0.0003184455-0.0008503633
-0.0000702981-0.0001994232-0.0005311096
-0.0000194414-0.000054984-0.0001460162
0.0000426750.00012029990.0003184952
0.00011854420.00033301540.0008788028
0.0002112110.00059115590.0015546629
0.00032439460.00090442180.0023699057
0.00046263720.0012845850.0033532763
0.00063148720.00174593140.0045394476
0.00083772110.00230579740.0059702433
0.00108961560.00298522180.0076961124
0.00139728040.00380973590.0097779079
0.00177306290.00481032340.0122890326
0.00223204480.00602458460.0153180272
0.00279264650.00749814890.018971692
0.0034773670.009286390.0233788531
0.00431368640.01145650670.0286949042
0.00533516930.01409004770.0351072857
0.00658281140.01728597630.0428420943
0.00810668480.02116438950.0521720545
0.0099679480.02587103040.0634261346
0.01224130.03158276560.0770011465
0.01501797840.0385142310.0933757364
0.0184094210.04692589780.1131272621
0.02255173850.057133860.1369521499
0.02761117640.06952171320.1656904503
0.03379078780.0845549690.2003554575
0.04133858230.10279854810.2421694378
0.05055747920.12493800890.2926067257
0.06181746540.15180530960.353445708
0.07557044360.18441007150.4268315288
0.0923683690.22397751850.5153517258
0.11288540150.27199451890.6221274651
0.13794496160.33026545870.7509235917
0.16855277740.40098004730.9062813756
0.20593724810.48679560231.0936786341
0.25159874360.59093690651.3197228759
0.30736982020.71731738881.5923842781
0.3754887670.87068618371.9212767093
0.45868943651.05680659412.3179967085
0.56031096371.28267266552.7965323722
0.68443177741.55677200853.3737565652
0.83603328151.88940474684.0700218474
1.02119977672.29307057614.9098780924
1.24736264472.78293847845.9229381004
1.52359859553.37741674317.1449217265
1.86099394784.09884471478.6189153405
2.27308956154.974332262710.3968910253
2.77642428086.036778517712.5415390789
3.39119869527.326108157415.1284784356
4.14208586078.890771698518.248922941
5.059221515610.789566174222.0128974952
6.179413534113.093844612326.5531174604
7.547619155215.890197344732.0296681215
9.218749274519.283705904638.6356491913
11.259872211523.401891787546.6039833849
13.752905396528.399508462556.2156291267
16.797903004934.464356708967.8094869672
20.517071482341.824341806781.7943490019
25.059674118650.756037776598.6633126221
30.608021507961.5950804968119.0111668171
37.384788312474.7487802522143.555364058
45.661949978990.7114276668173.1613172177
55.771698068110.0828681908208.8729134819
68.1197722684133.5910431336251.9493211509
83.2017441547162.1193442922303.9093871176
101.6229062151196.7398101078366.5851904486
124.1225643642238.7534107995442.1866403331
151.6037088851289.7389363116533.379396084
185.1692546004351.6123241894643.3788565987
226.1663047163426.6986568109776.0635332916
276.2402148042517.8195334901936.1118039531
337.4006266974628.39910072841129.1668693926
412.102122474762.59272502431362.0357291297
503.3427354542925.44314351861642.9291918927
614.78427180451123.06996031341981.7513835421
&A
Pgina &P
300 K
310 K
320 K
V (mV)
I (mA)
Zener
-1
-1
-0.95
-0.9
-0.8
-0.24
-0.154
-0.084
-0.036
-0.012
-0.000253624
-0.0002433562
-0.0002308151
-0.0002154974
-0.0001967883
-0.0001739369
-0.0001460262
-0.000111936
-0.0000702981
-0.0000194414
0.000042675
0.0001185442
0.000211211
0.0003243946
0.0004626372
0.0006314872
0.0008377211
0.0010896156
0.0013972804
0.0017730629
0.0022320448
0.0027926465
0.003477367
0.0043136864
0.0053351693
0.0065828114
0.0081066848
0.009967948
0.0122413
0.0150179784
0.018409421
0.0225517385
0.0276111764
0.0337907878
0.0413385823
0.0505574792
0.0618174654
0.0755704436
0.092368369
0.1128854015
0.1379449616
0.1685527774
0.2059372481
0.2515987436
0.3073698202
0.375488767
0.4586894365
0.5603109637
0.6844317774
0.8360332815
1.0211997767
1.2473626447
1.5235985955
1.8609939478
2.2730895615
2.7764242808
3.3911986952
4.1420858607
5.0592215156
6.1794135341
7.5476191552
9.2187492745
11.2598722115
13.7529053965
16.7979030049
20.5170714823
25.0596741186
30.6080215079
37.3847883124
45.6619499789
55.771698068
68.1197722684
83.2017441547
101.6229062151
124.1225643642
151.6037088851
185.1692546004
226.1663047163
276.2402148042
337.4006266974
412.102122474
503.3427354542
614.7842718045
&A
Pgina &P
Vz
V (mV)
I (mA)
Curva caracterstica de un diodo Zener
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Modelo del diodo para pequea seal (con fuente de dc y ac)Dos modelos: De gran seal (CD) De pequea seal (AC) Modelo de gran seal: En un punto de operacinespecfico punto de operacin Q Modelo de pequea seal Pequea variacin alrededorde un punto de operacin Considera slo el efecto defuentes de CA Aplicaciones de modelo depequea seal Anlisis de CA, respuesta defrecuencia
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Tres modelos de diodo
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Figura 3.11. Rectificador de media onda con carga resistiva.(a) Diagrama del circuito (b) Tensin de la fuente en funcin del tiempo (c) Tensin de la carga en funcin del tiempo Diodo ideal 0,7 VDiodorealVmsen ( t)
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Figura 3.23. Puertas lgicas con diodos.(a) Puerta OR(b) Puerta AND
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Figura 3.31. Curva caracterstica del diodo, mostrando el punto Q.Punto Q
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Figura 3.32. Corrientes de los diodos.
*****Se elimina el smbolo delta, y designa a los cambios de corriente y tensin, a partir de los valores del punto Q, como vd y id. Por tanto, para esas pequeas seales de alterna, se escribe la ecuacion 4
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