-1- Cu hi & bi tp (1) (phn tr li & bi gii ca sinh vin) H & tn sinh vin: . . . . . . . . . . . . . . . . . . . Nhm hp: . . . . . . Lp: . . . . . . . . -2- Lu : Misinhvinhyttrlicuhivlmbitptrctipvotiliuny (bn giy kh A4). Khng sao chp bi gii ca ngi khc. iviphncuhitrcnghim,SV lmbicnsuynghthtktrckhi chnbngcchkhoanhtrnhocnhduvongaytrcmtphngn ngnht,vgiithchngngnvophntrngbncnhhocphadimi cuhi.iviccbitp,hyghiligiivophntrngtngngmi bi tp. Ti liu tham kho: - Bi ging Cu kin in t. (2001) [D Quang Bnh]. - Electronic Devices. (2005) [Thomas L. Floyd]. - Fundamentals of Linear Electronics Integrated and Dicrete. (1998).[James Cox ]. - Lin h khi cn: Thy Bnh,0905894666,hoc: email: binhduquang@.gmail.com Thi hn hon thnh v np bi tp:( vo bui thi gia k ) tibm:int,Khoaint-Vinthng,TrngihcBchKhoa Nng54NguynLngBng,QunLinChiu,TpNng.(khngchp nhn s chm tr). -3- Cu hi v cht bn dn 1. Mi nguyn t bit u c (a) kiu cc nguyn t ng nht; (b) s lng cc nguyn t nh nhau;(c) kiu nguyn t duy nht;(d) nhiu kiu nguyn t khc nhau. 2.Mt nguyn t bao gm (a) mt nhn v ch mt in t; (b) mt nhn v mt hoc nhiu in t; (c) cc proton, cc in t, v cc neutron;(d) c (b) v (c). 3.Nhn ca mt nguyn t c to thnh bi (a) cc proton v cc neutron; (b) cc in t; (c) cc in t v cc proton; (d) cc in t v cc neutron. 4.S nguyn t lng ca Silicon l (a) 8; (b) 2; (c) 4; (d) 14. 5.S nguyn t lng ca Germanium l (a) 8; (b) 2; (c) 4; (d) 32. 6. Lp ha tr trong mt nguyn t silicon c s th t l (a) 0; (b) 1; (c) 2;(d) 3. 7.in t ha tr c (a) qu o gn nhn nht; (b) qu o xa nhn nht;(c) cc qu o khc nhau xung quanh nhn; (d) khng lin quan vi mt nguyn t c th. 8.Ion dng c hnh thnh khi (a) mt in t ha tr thot ra xa khi nguyn t; (b) c nhiu l trng hn so vi in t qu o ngoi cng; (c) hai nguyn t lin kt vi nhau; (d) khi mt nguyn t nhn thm mt in t ha tr . 9.Nguyn t c s dng ph bin lm vt liu bn dn trong cc cu kin in t l (a) germanium; (b) carbon;(c) ng;(d) silicon. -4- 10.Di nng lng m trong cc in t t do tn ti l (a) di th nht;(b) di th hai; (c) di dn;(d) di ha tr. 11.Cc cp in t - l trng c to thnh bi (a) s ti hp;(b) nng lng nhit; (c) s ion ha; (d) s pha tp. 12.C s ti hp khi (a) mt in t ri vo mt l trng;(b) mt ion dng v mt ion m lin kt vi nhau; (c) in t di ha tr tr thnh in t di dn; (d) mt tinh th c hnh thnh. 13.Trong tinh th bn dn, cc nguyn t c lin kt vi nhau do (a) s tng tc ca cc in t ha tr;(b) cc lc hp dn; (c) cc lin kt ng ha tr; (d) c (a), (b), v (c). 14.Mi nguyn t trong tinh th silicon c (a) bn in t ha tr; (b) bn in t trong di dn; (c) tm in t ha tr, 4 in t ca chnh nguyn t v 4 in t c gp chung; (d) khng c cc in t ha tr do tt c in t c gp chung vi cc nguyn t khc. 15.Nguyn t c s dng ph bin lm vt liu bn dn trong cc cu kin in t l (a) germanium; (b) carbon;(c) ng;(d) silicon. 16.Trong cht bn dn thun (c bn) (a) khng c cc in t t do;(b) cc in t t do c to ra do nhit;(c) ch c cc l trng;(d) c bao nhiu in t s c by nhiu l trng; (e) gm c (b) v (d). 17.S khc nhau gia cht cch in v cht bn dn l (a) khe nng lng rng hn gia di ha tr v di dn; (b) v s lng cc in t t do; (c) v cu trc nguyn t; (d) gm c (a), (b), v (c). -5- 18.Qu trnh b sung tp cht vo cht bn dn thun gi l (a) s pha tp; (b) s ti hp;(c) s bin i nguyn t;(d) s ion ha. 19.Tp cht ha tr 3 c b sung vo silicon to thnh (a) germanium; (b) cht bn dn tp dng-n; (c) cht bn dn tp dng-n; (d) vng ngho. 20.Chc nng ca tp cht ha tr 5 l (a) lm gim dn in ca silicon; (b) tng s lng l trng; (c) lm tng s lng cc in t t do;(d) to ra cc ht ti in thiu s. 21.Cc ht ti in a s trong bn dn tp dng-n l (a) cc l trng; (b) cc in t ha tr; (c) cc in t trong di dn; (d) cc proton. 22.Cc l trng trong bn dn tp dng-n l (a) cc ht ti in thiu s c to ra do nhit; (b) cc ht ti in thiu s c to ra do pha tp; (c) cc ht ti in a s c to ra do nhit; (d) cc ht ti in a s c to ra do pha tp. 23.Tip gip pn c to thnh do (a) s ti hp ca cc in t v l trng; (b) s i-on ha; (c) bin gii ca vt liu dng-p v dng-n; (d) s va chm ca mt proton v mt neutron. 24.Vng ngho c to ra do (a) s i-on ha; (b) s khuych tn;(c) s ti hp;(d) gm c (a), (b), v (c). 25.Vng ngho gm (a) vng khng c ci g ngoi cc ht ti in thiu s;(b) cc i-on dng v m; (c) khng c cc ht ti in a s; (d) c (b) v (c). 26.Thut ng phn cc [bias] c ngha l (a) t s ca ht ti in a s i vi ht ti in thiu s; (b) mc dng in chy qua diode; (c) mc in p dc t vo iu khin s hot ng ca mt cu kin; (d) ngoi cc phng n trn. -6- 27. phn cc thun mt diode (a) in p ngoi t vo l dng ti anode v m ti cathode; (b) in p ngoi t vo l m ti anode v dng ti cathode; (c) in p ngoi t vo l dng ti vng p v m ti vng n; (d) c (a) v (c). 28.Khi mt diode c phn cc thun, (a) dng in duy nht l dng l trng; (b) dng in duy nht l dng in t; (c) dng in duy nht l c to ra do cc ht ti in a s; (d) dng in c to ra do c cc l trng v cc in t. 29.Mc d dng in b ngng khi phn cc ngc, (a) nhng c mt mc dng in no do cc ht ti in a s; (b) nhng c mt mc dng in rt nh do cc ht ti in thiu s; (c) nhng c dng do nh thng thc. 30.i vi mt diode silicon, tr s ca in p phn cc thun in hnh (a) cn phi ln hn 0,3V; (b) cn phi ln hn 0,7V; (c) ty thuc vo rng ca vng ngho; (d) ph thuc vo nng ca ht ti in a s. 31.Khi c phn cc thun, diode (a) ngng dn; (b) dn dng; (c) c in tr cao; (d) s gim mc in p ln. 32.Khitvoltmeterngangquadiodecphnccthun,thvoltmeterschthmcinp xp x bng vi (a) mc in p ca ngun pin phn cc; (b) 0V;(c) th ro ca diode;(d) in p ca ton b mch. 33.Mt diode siliconmcni tip vi in tr 1,0kO vmt ngun pin 5V. Nu anode cmc vi cc dng ca ngun pin, in p cathode so vi u m ca ngun pin l (a) 0,7V;(b) 0,3V;(c) 5,7V;(d) 4,3V. 34. uqueodngcanghointr [ohmmeter]cktnivianodecadiodecn u que m l kt ni vi cathode. Diode l (a) c phn cc ngc; (b) h mch;(c); c phn cc thun (d) b hng; (e) gm c (b) v (d). -7- BI TP. CC BI TP C BN Mc 1-1 CU TRC CA NGUYN T 1.Nu s nguyn t ca mt nguyn t trung ha l 6, th c bao nhiu in t c trong nguyn t? proton l bao nhiu?. 2.S lng in t ln nht l bao nhiu c th c lp th 3 ca mt nguyn t? Mc 1-2 CHT BN DN, CHT DN IN, V CHT CCH IN 3.Vi mi gin nng lng hnh 1.40, hy xc nh loi vt liu cn c vo cc so snh tng i. 4.Mt nguyn t c 4 in t ha tr. Kiu nguyn t thuc loi vt liu no? Mc 1-3 LIN KT NG HA TR 5.Trong tinh th silicon, mu nguyn t n thc hin bao nhiu lin kt ng ha tr? -8- Mc 1-4 S DN IN TRONG CC CHT BN DN 6.iu g xy ra khi gia tng nhit vo cht bn dn? 7.Tn gi hai vng nng lng m trong dng in s c to ra trong cht bn dn? Mc 1-5 CC CHT BN DN TP DNG-N V DNG-P 8.Hy m t qu trnh pha tp v gii thch qu trnh pha tp bin i cu trc nguyn t ca silicon nh th no? 9.Nguynt antimonycbaonhiuintha tr,c thsdnglmgtrongchtochtbn dn? Nguyn tboron c bao nhiu in t ha tr, c th s dng lm g trong ch to cht bn dn? Mc 1-6 DIODE 10.in trng tip gip pn c to ranh th no? 11.Do c th chn [barrier potential], diode c th c dng lm ngun in p c khng? Gii thch. Mc 1-7 PHN CC DIODE 12.diodecphncc thun,cnphimcudngcanguninpnvngbndn no ca tip gip? 13.Hy gii thch ti sao cn phi c in tr mc ni tip khi diode c phn cc thun. Mc 1-8 C TUYN V-A CA DIODE 14.Gii thch cch to ra phn c tuyn phn cc thun ca diode nh th no? -9- 15.Bng cch no c th lm cho ro th gim t 0,7V xung 0,6V? Mc 1-9 CC M HNH CA DIODE 16.Hy xc nh mi diode mch hnh 1.41, l c phn cc thun hay phn cc ngc. 17.Hy xc nh in p trn mi diode mch hnh 1.41, bng m hnh thc t ca diode. -10- CC BI TP V SAI HNG Mc 1-10 O THDIODE 18.Xemccschthtrnnghotrongmimchhnh1.42,vxcnhdiodenong chc nng, hay diode no h mch hoc b ngn mch. Gi s m hnh l tng. 19.Hy xc nh in p so vi t ti tng im o trong mch hnh 1.43. Gi s m hnh diode thc t. -11- Cu hi v mch Diode 1. Tr s trung bnh ca in p ra mch chnh lu bn k c gi tr nh 200V l (a) 63,7V; (b) 127,3V;(c) 141V;(d) 0V. 2. in p sin 60Hz t vo u vo ca mch chnh lu bn k, tn s ca tn hiu ra l (a) 120Hz; (b) 30Hz; (c) 60Hz;(d) 0Hz. 3.Tr s trung bnh ca in p ra mch chnh lu bn k c gi tr nh 200V l (a) 10V; (b) 3,18V;(c) 10,7V;(d) 9,3V. 4.Tr s nh ca in p u vo ca b chnh lu bn k l 10V. Tr s nh ca in p ra xp x bng (a) 10V; (b) 5V;(c) 20V;(d) 3,18V. 5.Tr trung bnh ca in p ra mch chnh lu ton k c gi tr nh 75V l (a) 53V;(b) 47,8V; (c) 37,5V;(d) 23,9V. 6.in p sin 60Hz t vo u vo ca mch chnh lu ton k, tn s ca tn hiu ra l (a) 120Hz; (b) 60Hz; (c) 240Hz;(d) 0Hz. 7.in p ton b cun th cp ca mch chnhlu ton k im gial 125Vrms. B qua st p trn diode, in p ra hiu dng l (a) 125V; (b) 177V; (c) 100V;(d) 62,5V. 8.Khi in p ra nhl100V, PIV ca mi diode mch chnhlu ton k im gial (b qua st p trn diode) (a) 100V; (b) 200V; (c) 141V; (d) 50V. 9.Khi in p ra hiu dng ca mt mch chnh lu ton k kiu cu l 20V, th in p nh ngc c trn cc diode l (b qua st p ca diode) (a) 20V; (b) 40V; (c) 28,3V; (d) 56,6V. -12- 10.in p ra dc l tng ca mt mch lc bng t l (a) gi tr nh ca in p c nn; (b) gi tr trung bnh ca in p c nn (c) gi tr hiu dng ca in p c nn 11.Mch lc ca b ngun cung cp cung cp to ra in p c gn l 100mV nh-nh v gi tr dc l 20V. H s gn l (a) 0,05;(b) 0,005;(c) 0,00005; (d) 0,02. 12.Tr s in p chnh lu ton k l 60V nh c a n u vo ca b lc bng t. Nu f = 120Hz; RL = 10kO; v C = 10F, mc in p gn bng(a) 0,6V;(b) 6mV;(c) 5,0V;(d) 2,88V. 13.Nu in tr ti ca b chnh lu ton k c lc bng t c gim xung, th in p gn (a) s tng;(b) s gim xung; (c) khng b nh hng; (d) c tn s khc. 14. n nh ngun [line regulation] c xc nh bng (a) dng ti;(b) dng zener v dng ti; (c) thay i in tr ti v in p ra;(d) thay i in p ra v in p vo. 15. n nh ti [load regulation] c xc nh bng (a) thay i dng ti v in p vo;(b) thay i dng ti v in p ra; (c) thay i in tr ti v in p vo; (d) thay i dng zener v dng ti. 16.in p sin nh-nhl 10V t ngang qua mt diode silicon v in tr ni tip. in p ln nht ngang qua diode l,(a) 9,3V;(b) 5V; (c) 0,7V; (d) 4,3V. 17.Nu in p vo a n b nhn ba in p c tr s hiu dng l 12V, th mc in p ra l vokhong (a) 36V; (b) 50,9V; (c) 33,9V; (d) 32,4V. 18.Nu mt diode trong mch chnh lu ton k kiu cu h mch, th mc in p ra bng (a) 0V; (b) mt phn t bin ca in p vo; (c) mc in p chnh lu bn k;(d) mc in p c tn s 120Hz. 19.Nu khi kim tra mtmch chnh lu cu ton k kiu 60Hz, v thy rng in p ra c gn 60Hz, th (a) mch ang lm vic ph hp;(b) c mt diode h mch; (c) cun th cp ca bin p b ngn mch;(d) t lc b r. -13- BI TP. CC BI TP C BN Mc 2-1 MCH CHNH LU BN K 1.V dng sng v ghi tr s ca in p ra cho mi mch hnh 2.68. 2.Mc dng thun nh chy qua mi diode mch hnh 2.68, l bao nhiu? 3.Bin p ngun cung cp c t s vng dyl 5:1. Mc in p cun dy th cplbao nhiu nu in p cun dy s cp c mc vo ngun 115V rms? 4.Xc nh mc cng sut nh v trung bnh c phn b n RL mch hnh 2.69. -14- Mc 2-2 MCH CHNH LU TON K 5. Tnh tr trung bnh cho mi in p ghi hnh 2.70. 6. Xt mch hnh 2.71. (a) Kiu mch ny l mch g? (b) in p nh th cp ton b l bao nhiu? (c) Tnh in p nh trn mi na cun dy th cp. (d) V dng sng in p trn RL. (e) Mc dng nh chy qua mi diode l bao nhiu? (f) PIV ca mi diode trong mch l bao nhiu? -15- 7.Tnhinpnhtrnminacabinpimgiacundycdngtrongbchnhluton k c mc in p ra trung bnh l 110V. 8.Hy th hin cch mc cc diode b chnh lu im gia nh th no to ra in p ton k theo chiu m trn in tr ti. 9.Thng s PIV cn phi c l bao nhiu cc diode trong mch chnh lu cu to ra mc in p ra trung bnh l 50V? 10. in p ra ca mch chnh lu cu l 20V. Mc in p ngc nh trn cc diode l bao nhiu? 11.Vdngsnginpracamchchnhlucuhnh2.72.Lultonbdiodec o ngc so vi cc mch trc y. Mc 2-3 MCH LC NGUN CUNG CP V MCH N NH IN P 12.Mchlccabchnhlucungcpinpradcl75Vviinpgnnh-nhl0,5V. Tnh h s gn. -16- 13.Mch chnh lu ton k c mc in p ra nh l 30V. B lc bng t u vo s c mc vi b chnh lu. Tnh mc gn nh-nh v mc in p ra dc trn in tr ti 600O. 14.Mc gn ca mch lc chnh lu bi tp 13 l bao nhiu phn trm? 15.Tr s ca t lc cn phi c l bao nhiu cho h s gn 1% ca b chnh lu ton k c in tr ti l 1,5kO? Cho bit b chnh lu cung cp mc in p ra nh l 18V. 16.Mch chnh lu ton k c mc in p chnh lu nh l 80V t ngun ac 50Hz. S dng t lc 10F, xc nh h s gn vi in tr ti l 10kO. 17.Tnh mc gn nh-nh v mc in p ra dc mch hnh 2.73. Bin p c thng s in p th cp l 36V, v in p ngun in c tn s 60Hz. 18.Xemmch hnh 2.73, v v dng sng in p theo quan h vi in p vo: VAB, VAD, v VCD. -17- 19.Nu in p ra khng ti ca b n nh in p l 15,5V v in p ra y ti l 14,9V, th n nh ti theo phn trm l bao nhiu?. 20. Gi sb n nh in p c n nh ti theo phn trml 0,5%. Mc in p ra y til bao nhiu nu mc in p ra khng ti l 12,0V?. Mc 2-4 CC MCH HN CH V MCH GHIM BNG DIODE 21.Hy xc nh dng sng ra cho mch hnh 2.74. 22.Hy xc nh in p ra cho mch hnh 2.75(a) tng ng vi mi in p vo hnh 2.75(b), (c), v (d). -18- 23.Hy xc nh dng sng ca in p ra cho mch hnh 2.76. 24.Hy xc nh dng sng ca in p trn ti RL cho mi mch hnh 2.77. -19- 25.Hy v dng sng ca in p ra cho mi mch hnh 2.78. 26.Hy xc nh dng sng ca in p ra cho mi mch hnh 2.79. -20- 27.Hy xc nh dng sng ca in p ra cho mi mch hnh 2.80. Cho bit hng s thi gian RC l ln hn nhiu so vi chu k ca tn hiu vo. 28.Lp li bi tp 27 vi cc diode c mc xoay ngc chiu. -21- Mc 2-5 MCH NHN IN P 29.Mtmchbipc20Vrmstiuvocamch.Mcinpuralbaonhiu?Hyv mch, ch r cc u ra v thng s PIV ca diode. 30.Lp li bi tp 29 cho b nhn 3 in p v b nhn 4 in p. Mc 2-6 TRANG S LIU CA DIODE 31.T trang s liu hnh 2.55, hy xc nh in p ngc nh l bao nhiu m diode 1N183A c th chu ng c. 32.Lp li nh bi tp 31 cho diode 1N188A. 33.Nu in p ra nh ca mch chnh lu cu ton k l 50V, xc nh tr s nh nht ca in tr hn ch xung gn cn thit khi s dng diode 1N183A. -22-

-23- CC BI TP V SAI HNG Mc 2-7 SAI HNG 34.Nu 1 trong s cc diode b chnh lu cu b h mch, th in p ra s nh th no? 35. T cc s ch th trn ng h o mch hnh 2.81, hyxc nhxemb chnhlu anghot ng bnh thng khng? Nu khng bnh thng, xc nh h hng c th d xy ra nht. 36.Hnh 2.82, l th hin dng sng in p ra ca cc mch chnh lu khc nhau hin th trn my hinsng.Theomitrnghp,hyxcnhmchchnhluchotngngchcnng khng v nu khng ng chc nng th hy xc nh h hng c th d xy ra nht. -24- 37. Cn c vo cc gi tr ca cu kin cho (ghi trong mch),mch hnh 2.83 c th h hng khng? Nu nh vy th ti sao? CC BI TP NG DNG H THNG 38. Hyxc nhsaihng c th d xy ranht trong bngmch hnh 2.84 theo mihin trng diy.Trngthihotnglinquancnphilytheotngtrnghp.Binpcmc in p ra nh mc l 36V. (a) Khng o c in p t im o 1 i vi im o 2. (b) Khng c in p t im 3 i vi im o 4, 110V rms t im o 1 i vi im o 2. (c) 50V t im o 3 i vi im o 4. in p vo ng mc 110V rms. (d) 25V t im o 3 i vi im o 4. in p vo ng mc 110V rms. (e) in p chnh lu ton k c mc nh khong 50V ti im o 7 so vi t. (f) in p gn 120Hz cao ti im o 7. (g) in p gn c tn s 60Hz ti im o 7. (h) Khng c in p ti im o 7. -25- 39.Trong khi o th bngmch ngun cung cp hnh 2.84 c mc in tr ti 10kO, o in p ti u dng ca tlc c in p gn 60Hz. Thay ton b diode, cm phch inngun vo bng mch, v o li im o kim chng hot ng c ng khng v thy rng in p o vn c in p gn 60Hz. Sai hng lc ny l gi? 40.Nudiodephatrncngbngmchhnh2.84,lpsaibongc,thinpctho c ti im o 8 l bao nhiu? CC BI TP NNG CAO 41.Mt mch chnh lu ton k c t lc cung cp in p ra dc l 35V cho ti 3,3kO. Hy xc nh tr s nh nht ca t lc nu mc in p gn nh-nh yu cu l 0,5V. 42.Mt mch chnh lu ton k cha lc vi mc in p vo l 220V; 50Hz cung cp in p ra c mc nhl 15V. Khimcmchlc u vo bng t v til 1kO, in p ra dc l 14V. Mc in p gn nh-nh l bao nhiu?. 43.Vi mt b chnh lu ton k, dng xung o c b lc bng t l 50A. Bin p c thng s in p th cp l 24V vi in p vo l 110V; 60Hz. Hy tnh tr s ca in tr xung gn cn trong mch ny. 44.Thit k b chnh lu ton k s dng bin p im gia 18V. gn u ra khng vt qu 5% bin in p ra, vi in tr ti l 680O. Ch r cc thng s nh mc Io v PIV ca cc diode v chn diode thch hp t hnh 2.55. -26- 45.Thit k b ngun cung cp c lc c th cho cc mc in p ra l + 9V 10% v - 9V 10% vi mc dng ti ln nht l 100mA. Hai mc in p phi c chn bng chuyn mch thit lp hai u ra. in p gn cn phi khng vt qu 0,25V rms. 46.Thit k mch xn in p sin 20V rms thnh in p xung c bin dng ln nht l 18V v bin m ln nht l 10V s dng ngun in p dc n 24V. 47.Hy xc nh mc in p trn mi t trong mch hnh 2.85. -27- Cu hi v phn Diode c bit 1. Cathode ca diode zener mc trong b n nh in p thng l (a) dng hn so vi anode;(b) m hn so vi cathode; (c) c mc in p + 0,7V; (d) c ni t. 2.Nu mt diode zener c in p zener l 3,6V th diode zener s lm vic (a) vng nh thng c n inh; (b) vng nh thng zener; (c) vng dn thun;(d) vng nh thng thc. 3.Mtdiodezener12V, thayidngzener10mAsto ra thayiinpzenerl 0,1V. Tr khng ca zener tng ng vi khong dng trn l (a) dng hn so vi anode;(b) m hn so vi cathode; (c) c mc in p + 0,7V; (d) c ni t. 4.S liu ca mt diode zener cho l VZ = 10V o ti mc dng IZT = 500mA. ZZ tng ng l (a) 50O; (b) 20O; (c) 10O;(d) cha bit. 5. Trng thi khng ti c ngha l (a) ti c in tr v cng; (b) ti c in tr bng khng; (c) cc u ra l h mch; (d) gm c (a) v (c). 6. Diode bin dung biu hin (a) in dung c th thay i ty thuc vo in p ngc; (b) in tr c th thay i ty thuc vo in p ngc; (c) in dung c th thay i ty thuc vo in p thun; (d) in dung khng i trn khong in p ngc. 7. Diode pht quang - LED (a) s pht sng khi c phn cc ngc;(b) s nhy cm vi nh sng khi phn cc ngc; (c) s pht sng khi c phn cc thun;(d) hot ng nh mt bin tr. 8. LED hng ngoi so vi LED thy c l (a) to ra nh sng c bc sng ngn hn;(b) to ra nh sng tt c cc bc sng; (c) to ra ch mt mu ca nh sng;(d) to ra nh sng c bc sng di hn. 9. in tr ni ca quang diode - photodiode (a) s tng ln theo cng nh sng khi c phn cc ngc; (b) s gim xung theo cng nh sng khi c phn cc ngc; (c) s tng ln theo cng nh sng khi c phn cc thun;; (d) s gim xung theo cng nh sng khi c phn cc thun.. -28- 10.Diode c c tuyn in tr m l (a) diode Schottky; (b) diode tunnel; (c) diode laser; (d) diode ht ti nng [hot-carrier diode]. 11. LED hng ngoi c ghp quang vi photodiode. KhiLED chuyn sang ngng dn, s ch th trn ammeter mc ni tip vi photodiode c phn cc ngc s (a) khng thay i;(b) gim;(c) tng;(d) thay i bt thng. 12. chomt h thng hot ng ng chc nng, th ccloimch khcnhau to nnh thng cn phi (a) c phn cc ng; (b) c kt ni ng; (c) c giao tip ng; (d) tt c cc phng n trn; (e) gm c (a) v (b). BI TP. CC BI TP C BN Mc 3-1 DIODE ZENER 1.Mt diode zener c VZ = 7,5V v ZZ = 5O ti mc dng o. V mch tng ng ca zener. 2.T c tuyn hnh 3.58, dng zener nh nht (IZK) v in p zener ti mc IZKgn ng l bao nhiu ? -29- 3.Khi dng ngc trong mt diode zener tng ln t 20mA n 30mA, th in p zener s thay i t 5,6V n 5,65V. Tr khng ca zener l bao nhiu? 4.Mt diode zener c tr khng l 15O. in p u cc ca zener l bao nhiu ti mc dng 50mA nu VZT = 4,7V ti mc dng IZT = 25mA? 5. Mt diode zener c cc thng s sau: VZ = 6,8V ti 25C vh s nhit TC = + 0,04% /C. Hy xc nh in p zener ti 70C. Mc 3-2 CC NG DNG CA DIODE ZENER 6.Xcnhmcinpvo thpnhtcnthitcs nnhchomchcthitlpnh hnh 3.59. Gi thit diode zener l tng c IZK = 1,5mA v VZ = 14V. 7.Lp li nh bi tp 6 vi ZZ = 20O v VZT = 14V ti mc dng 30mA. 8.Cn phi iu chnh R trong mch hnh 3.60, n gi tr no to ra IZ = 40mA? Gi thit VZ = 12V ti mc dng 30mA v ZZ = 30O. 9.t in p sin 20V nh vo mch hnh 3.60, thay cho ngun dc. V dng sng ra. S dng gi tr ca cc thng s cho bi tp 8. -30- 10.B n nh bng zener c ti nh hnh 3.61. VZ = 5,1V ti IZT = 49mA; IZK = 1mA; ZZ = 7O, v IZM = 70mA. Xc nh cc mc dng ti cho php ln nht v nh nht. 11.Tnh n nh ti theo phn trm cho bi tp 10. [NL FLFLLoad regulation = 100%V VV| | |\ .] 12. Phn tch mch hnh 3.61, c n nh ngun tnh theo phn trm khi s dng in p vo t 6V n 12V khng ti. [OUTINLine regulation 100%VV| | A=|A\ .] 13.Mch n nh bng zener c in p ra khng til 8,23V, v in p ra y til 7,98V. Tnh n nh ti tnh theo phn trm. [NL FLFLLoad regulation = 100%V VV| | |\ .] 14. b n nh bng zener, khong thay i ca in p ra l 0,2V khi in p vo t 5V n 10V. n nh ngun theo phn trm l bao nhiu? [OUTINLine regulation 100%VV| | A=|A\ .] 15. in p ra ca b n nh bng zener l 3,6V khi khng ti v 3,4V khi y ti. Tnh n nh ti theo phn trm. [NL FLFLLoad regulation = 100%V VV| | |\ .] -31- Mc 3-3 DIODE BIN DUNG -VARACTOR 16. Hnh 3.62, l c tuyn in p ngc theo in dung ca mt varactor. Hy xc nh thay i theo in dung nu VR thay i t 5V n 20V. 17.Hy xt c tuyn hnh 3.62, v xc nh gi tr ca VR c in dung 25pF. 18.Gi tr in dung cn thit cho mi varactor mch hnh 3.63,l bao nhiu to ra tn s cng hng l 1MHz?

19.Ti gi tr no cn phi c in p VR cho bi tp 18 nu varactor c c tuyn nh hnh 3.62? Mc 3-4 DIODE PHT QUANG 20. LED hnh 3.64(a) c c tuynphtquangnh hnh3.64(b).Bquast p thun ca LED, hy xc nhmccngsutpht x(nhsng)ctora theo mW. -32- 21.Hyxcnh cchmcb hin thbyon hnh3.65, hinths5. Dngthunlin tclnnhtcho miLEDl 30mA v s dng nguncungcp l + 5V. 22.Vimtphotodiodetimcchiusngcho,intrngcl200kOvinpngcl 10V. Dng chy qua photodiode l bao nhiu ? 23.in tr ca mi photodiode hnh 3.66, l bao nhiu? 24.Khingchuynmchhnh3.67, microammeterchthtnghaygim? Gi s D1 v D2 c ghp quang. -33- Mc 3-5 CC LOI DIODE KHC 25.c tuyn V-I ca mt diode tunnel cho thyl dng in thay i t 0,25mA n 0,15mA khi in p thay i t 125mV n 200mV. in tr l bao nhiu? 26.Kiu mch no thng hay s dng diode tunnel? 27.Mcchlmlchbmtnoctrongsdngdiodelaser?Tisaochlmlchringmt pha? CC BI TP V SAI HNG Mc 3-6 C LP SAI HNG 28. i viminhm ccmc in p o c ti cc im (1, 2, v 3) c ch th hnh 3.68, xc nhmch c hot ng ng chcnnghay khng, nhn dng cchhng c th xy ra nht. Zener c thng s 12V. (a) V1 = 110V rms; V2 = 30V dc; V3 = 12V dc. (b) V1 = 100V rms; V2 = 30V dc; V3 = 30V dc. (c) V1 = 0V; V2 = 0V; V3 = 0V dc. (d) V1 = 110V rms; V2 = 30V nh ton k 120Hz; V3 = 12V dc in p xung 120Hz.. (e) V1 = 110V rms; V2 = 9V; V3 = 0V.

-34- 29.in p u ra ca mch hnh 3.68, l bao nhiu xt theo mi trng hp hng sau y?. (a) D5 h mch.(b) R h mch. (c) C b r. (d) C h mch. (e) D3 h mch.(f) D2 h mch (g) T h mch.(h) F h mch. CC BI TP NG DNG H THNG 30.H thng tnh v iu khin c lp t ti nh ca khch hng. H thng ang c biu hin hot ng chp chn nn bn quyt nh kim tra trc tin bng mch ngun cung cp v thu / pht hng ngoi. Cn c vo hnh 3.69, hy xc nh vn . 31.Mt vn khc c h thng tnh v iu khin. Lc ny, h thng ngng hot ng hon ton vbnliquytnhkimtratrctinbngnguncungcp.Cncvothngtinhnh 3.70, hy xc nh vn . -35- 32.LitkccnguynnhncthclmchoLEDhnh3.55khngphttiahngngoikhi ngun cung cp c ni vi ngun in li. 33.Litkccnguynnhncthclmchophotodiodehnh3.55khngpngvitia hngngoi pht ra t LED. Nu cc bc theo trnh t c th c lp vn . -36- BI TP V TRANG S LIU 34.Tham kho trang s liu ca diode zener hnh 3.7. (a) tiu tn cng sut dc ln nht ca diode 1N4738 ti 25C l bao nhiu?. (b) Xc nh tiu tn cng sut ln nht ca diode 1N4751 ti 70C v 100C?. (c) Mc dng nh nht ca 1N4738 cn cho s n nh l bao nhiu?. (d) Mc dng ln nht ca 1N4750 ti 25C l bao nhiu?. (e)Dngchyqua1N4750 thayit25mAn0,25mA.Trkhngzenercnphithayi nh th no?

-37- (f) in p zener ln nht ca 1N4736 ti 50C l bao nhiu?

(g) in p zener nh nht ca 1N4747 ti 75C l bao nhiu?. 35.Tham kho trang s liu ca diode bin dung hnh 3.22. (a) in p ngc ln nht ca diode 1N5139 l bao nhiu?. -38- (b) Xc nh tiu tn cng sut ln nht ca diode 1N5141 ti nhit mi trng l 60C?. (c) Xc nh tiu tn cng sut ln nht ca diode 1N5148 ti nhit v l 80C?. (d) Ti mc in p ngc 20V in dung ca 1N5148 l bao nhiu?.

(e) Nu ch tiu chun h s phm cht, th cn phi chn diode bin dung no?

(f) in dung in hnh ca 1N5142 l bao nhiu ti VR = 60V?

36.Tham kho trang s liu ca diode pht quang - LED hnh 3.31. (a) C th t 9V theo chiu phn cc ngc ngang qua mt MLED81 c khng?. (b) Xc nh tr s nh nht ca in tr ni tip vi MLED81 khi s dng in p 5,1V phn cc thun cho diode?. (c)Gismcdngthunl50mAvstpthunl1,5Vlmvicnhitxungquang45C. C vt qu thng s cng sut ln nht khng?. (d) Xc nh cng bc x theo mc dng thun l 30mA

(e) Cng bc x ti gc 20 tnh t trc l bao nhiu nu dng thun l 100mA?

37.Tham kho trang s liu ca photodiode hnh 3.36. (a)MtMRD82cmcnitipvimt intr10kOvnguninpphnccngc. Khng chiu sng vo diode. St p trn in trl bao nhiu?. (b) Ti bc sng no s c mc dng ngc ln nht theo chiu sng cho?. (c) Mc dng ti l bao nhiu ti nhit mi trng l 60C?. (d) Ti bc sng no nhy ca MRD821 mc ln nht?.

(e) Nu nhy ln nht l 50A / mW / cm2 , th nhy ti 900nm l bao nhiu?

(f) Tia hng ngoi vi bc sng l 900nm chiu vo MRD821 vi mc chiu sng l3mW /cm2v gc chiu l 40 t trc ln nht. Xc nh mc dng ngc. -39-

-40- -41- BI TP NNG CAO 38.Kho st s ca bng mch hnh 3.71, v xc nh kiu mch l mch g?. 39. Nu in pvo 110V rms; 60Hz cnin cc u vo ac, hyxc nh ccmc in p u ra trn bng mch hnh 3.71. 40.Nu mi u ra ca bng mch hnh 3.71, c mc ti c 1,0kO, thng s nh mc cn phi c s dng l bao nhiu?. -42- 41.Hy thit k b n nh in p bng zener m bo cc thng s sau: in p u vo l 24V dc, dng ti l 35mA, v in p trn ti l 8,2V. 42.Mchlcthngdicnghngbng varicap nh hnh 3.24 cn phi c thit k li to ra rng bng tn t 350kHz n850kHzgiihnsais10%.Sdng mch c bn hnh 3.72, xc nh tr s cc ttccccukinthamnthngs. S dng cc tr s tiu chun gn nht. 43.Thit k mch hin th bng LED by on hin th ch s bt k trong s 9 ch s s dng cc chuyn mch. Mi on LED c mc dng l 20mA 10% ly t ngun 12V v mch cn phi c thit k vi s lng cc chuyn mch t nht. 44.Nu s dng b hin th by on anode chung bi tp 43, hy thit k limch cho hin th cathode chung. -43- BI TP B SUNG PHN DIODE D1.1 Mt diode silicon dn nhit 25oC, vi mc st p trn hai cc diode l 0,7V. a) Xc nh mc st p V trn diode nu diode lm vic nhit +100oC v 100oC. (s: a) V = 0,55V; b) V = 0,95V). D1.2Mchhnh1.31S,dngchnhlusngsinc100Vrms vtns60Hz.Mcinpra nh nht khng th gim di 70V v t s binp l 1:2. in tr til 2kO. Tnh in dung cn thit ca t lc mc song song vi RL. (s: 8,25F). D1.3inpracabchnhlubnkvokhong50V,tns60Hz.Gistrthunca diode bng 0, ti thp nht c th mc vo mch khi s dng t khong 50F duy tr mc in p gn nh nht trn 40V l bao nhiu ? (s:1,67kO). D1.4Mch chnh lu ton k nh mch hnh 1.31S, c bin p vi t s vng dy l 5:1. a) Tnh tr s in dungca t cn duy trmc in pnh nht khong 10V trn ti 100O. (s:233F) b) Nuinptnhiuvophna)thayitrongkhongt110Vn120Vrms,tns 60Hz, th tr s in dung cn thit l bao nhiu ?(s: 233F). -44- D1.5Mt mch n nh bng diode Zener (hnh 1.37S) c in p u vo thay i trong khong t 10V n 15V v mc dng ti thay i trong khong t 100mA n 500mA. a)Tnh tr s ca Ri v IZmax, bit rng mch s dng diode zener 6V.(s: 6,33O; 1,32A).b)Hy tnh cng sut nh mc cho diode zener v in tr vo (Ri).(s: 7,92W; 12,8W). c) Hy tnh tr s ca t cn thit nu mc ngun l u ra ca mch nn bn k vi tn hiu vo l 60Hz.(s: 4731F). -45- D1.6a) Nu khng s dng in tr x RF trong mch hnh 1.37S, v bin p l bin p im gia 4:1vitnhiuvol120Vrms,60Hz.TnhtrscaRi cnthitduytr10Vtrnticmc dng thay it50mAn200mA.Bitinp thp nhtchophp tiuvo ca mch n nh l 14V. (s:14,8O) b)Tnh tr s in dung cn thit trong mch n nh (cho phn a) duy tr mc in p thp nht l 14V.(s: 875F). D1.7 Da theomchcabitpD1.6,chobitinpvo thay it110Vrms n120Vrms, 60Hz.Hytnhchntrsindungcatthchhpchocbinthindngtit50mAn 200mA v thay i in p vo cho trn. (s: C = 1160F). -46- 1.1XcnhdngsngracamchhnhP1.1,khitnhiuvovSldngsngvungi xng bin nh nh l 100V, c chu k l 2s. Gi thit rng diode l l tng. 1.2 Xc nh dng sng ra ca mch hnh P1.2, (diode l l tng) khi vS l: (a) Sng vung i xng 100V nh nh, c chu k l 2s. (b) Sng sin 100V nh nh, vi chu k l 2s. (c) Sng tam gic i xng 40V nh nh, vi chu k l 2s. 1.3Xc nh dng sng ra ca mch hnh P1.3, khi vS l sng sin 100V nh nh, c chu k l 2s. Gi s diode l l tng, v C = 0. -47- 1.4 V c tuyn ID theo VD cho mt diode silicon nu dng bo ha ngc IS = 0,1A, s dng n = 1,5 i vi silicon. Xc nh mc in p chuyn sang dn ca diode. 1.5VctuynID theoVD chomtdiodegermaniumnudngbohangcIS =0,01mA. Xc nh mc in p chuyn sang dn cho diode (c tuyn c th v trn cng trc th nh c tuyn ca bi tp 1.4). 1.6Mt diode thc t c dng bo ha ngc l 0,2A, n = 1,6, v VT = 26mV. Hy xc nh dng chyquadiodekhistptrndiodel0,4V.Tnhintr thuncadiodetiimlm vic ny. 1.7 Chomchhnh1.4,hyxcnhmcdngchyquadiodekhistpdctrndiodel 0,6V i vi khong dng ny v nVT = 40mV. 1.8 Cho mch hnh P1.5, tnh mc dng I3 (a) Khi cc diode c xem l l tng. (b)Khicc diodecxeml diodethc t, c Rf= 10O,v V =0,7V.Bqua dngbo ha ngc. -48- 1.9Nu ti u ra ca mt mch nn bn k l 10kO, th tr s ca t cn phi c l bao nhiu cmcinprakhngthayiqu5%?inpvol100Vrms,60Hz.Davohnh P1.1. Suy ra dng sng ra. 1.10Thitkmtbnguncungcptheokiumchnnbnknhntnhiuvol 120Vrms,60Hzvyucumcinpralnnhtl17Vvthpnhtl12V.Nguncung cp s cung cp in p ngun cho mch in t yu cu mc dng khng il 1A. Hy xc nh cu hnh mch, t s vng dy ca bin p, tr s ca t. Gi s cc diode v bin p l l tng. 1.11Nutiuracamchnntonkl10kO,trscatlbaonhiucnthitduytr mcinprakhngthayithpnhiusovi10%?Tnhiuvol110Vrms,60Hz.Da vo hnh 1.3. Suy ra dng sng ra. 1.12Lp li bi tp 1.10, vi kiu ngun cung cp l mch chnh lu ton k. -49- 1.13Hy xc nh thng s ca t trong mch hnh 1.31S,khia=6vRL =50O.Mcinp nhnhtntiyucukhngsuygimqu 20%. 1.14NumtdiodezenercmctrongmchnhhnhP1.6, trsintrRi lbaonhiu duy tr in p trn ti mc 10V (VZ) khi dng ti thay i t 50mA n 500mA v in p vo thay i t 15V n 20V ? Hy xc nh mc cng sut nh mc cn thit cho in tr v diode zener -50- 1.15MchnnhbngzenernhhnhP1.6,sdngdiodezener20Vduytrinp khng i 20V trn in tr ti RL. Nu in p vo thay i t 32V n 43V v dng ti bin thin t 200mA n 400mA, hy tnh chn tr s ca Ri gi in p khng i trn ti. Xc nh cng sut nh mc cn thit cho in tr v diode zener. 1.16 Mch n nh zener nh hnh P1.7, s dng diode zener 9V gi mc in p hng 9V trn ti, vi in p vo thay i t 18V n 25V v dng ra thay i t 400mA n 800mA. Gi s RZ = 0. (a) Chn tr s cn thit cho Ri v xc nh mc cng sut yu cu nh nht ca in tr vo. (b)Xc nh mc cng sut nh mc ca diode zener. (c) Tnh bin thin ca in p ra nh nh nu RZ = 1O. -51- 1.17 Gi skhng c tnhao trong cc diode nncamchnnton k (hnhP.18) vin= 2, tr scaRicnthitlbaonhiuduytrVLmc16Vvidngtil500mA,sdng zener16V?VS thayitrongkhongt110Vrmsn120Vrms,60Hz.GisRZ =0.Mc in p mch n nh cn phi khng c gim nhiu hn 8V trn mc VZ. 1.18Gi s khng c st p cc diode chnh lu trong mch hnh P1.8, v n = 2, tr s ca Ri cn thitlbaonhiuduytrVL =16Vvimcdngtikhong500mA?inpvoca binpl110Vrmsn120Vrms,60Hz.inpracamchnnclckhngth thayinhiuhn5V.Hyxcnhcngsutnhmccnthitchointrvdiode zener. -52- 1.19 Thit k b ngun n p ton k s dng bin p im gia 4:1 v diode zener 8V, 1W cung cp 8V khng i cho ti thay i t 200 On 500 O. in p vo ca bin p l 120Vrms, 60Hz. B qua tn hao trong bin p v cc diode. Xc nh: (a) IZmax v Izmin . (b) Ri v VSmin.(c) tr s t cn thit.(d) n nh theo % khi RZ = 2 O. 1.20Thit k b ngun n p ton k s dng bin p im gia 5:1 v diode zener 8V, 2W cung cp 8V khng i cho ti thay i t 100 O n 500 O. in p vo ca bin p l 120Vrms, 60Hz. B qua tn hao trong bin p v cc diode. Xc nh: (a) IZmax v IZmin.(b) Ri v VSmin.(c) tr s t cn thit.(d) n nh theo % khi RZ = 2 O.(e) Cng sut nh mc ca Ri. -53- 1.21S dng ccgi tr ca in pvo ivi Ri ca bi tp 1.18, nhng dng zener 12V, tr s ca Ri cn phi c l bao nhiu duy tr 12V u ra nu ti thay i t 20mA n 600mA ? Thng s ca t cn phi c l bao nhiu ? 1.22S dng mch hnh P1.8, v gi s khng c tn hao cc diode nn, tr s ca Ri l bao nhiuduytr12Vtrntibngcchsdngdiodezener12V,khiVS t105Vrms n 120Vrms, 60Hz ? inpra ca mchnn gim20% do thng s ca tC1,v ti thay it 50mA n 500mA. Thng s ca t l bao nhiu ? cho n = 2. -54- 1.23Visng vol 10sinet,dng sng ralnh th noiviccmchxnhnh P1.9 ? Gi s rng tt c cc diode l l tng vi V = 0 v Rf = 0. 1.24Trong cc mch xn bng diode hnh P1.10, vi = 20sinet, R = 2kO, v VR = 10V. in p chun ly t mch chia p 10kO c ni n ngun 100V. B qua tt c cc in dung. in tr thun ca diode l 100O, Rr ; v V = 0. V cc dng sng ra / vo. 1.25(a) in p vo vi ca mch xn hnh P1.11a, thay i tuyn tnh t 0 n 150V. V dng in p ra trn cng mt th theo thi gian vi in p vo. Gi s cc diode l tng. (b) Lp li nh phn (a) cho mch hnh P1.11b. -55- 1.26 (a) V dng sng ra ca mch hnh P1.12a, khi vi = 9sin1000t V. Th hin cc gi tr ln nht vnhnhttrndngsngvphngtrnhcangcongticcthiimkhcnhau. Gi s cc diode l l tng. (b) Lp li phn a) cho mch hnh P1.12b. 1.27Thit k mt mchxn nhn c dngsng ra nh hnh P1.13, t dng sngvung i xng u vo l 10V. Gi s V= 0,7V. -56- 1.28 Kiumchxnnhthnocnphic nhncccdngsngchohnhP1.14 ? Gi s tn hiu vo l 10sin t V. V mch v ghi tn cho mch. 1.29Thit k mch ghim c mc ghim + 2V i vi dng sng vung u vo ca mch nh hnh P1.15. Bin nh nh ca sng vo vung i xng l 4V, chu k l 100 s. -57- 1.30Mtnguninpsin10kHzl tngcccmcnh10Vsovi tcptnmchghimbng diodehnhP1.16.GisR, RS = 0, C = 1F, diode c Rr , Rf = 0, v V= 0. V dng sng ra. 1.31Tn hiu th hin hnh P1.16, c tn s l 1kHz c t vo mch, vi cc gi tr RS = 0, R = 10 kO, C = 0,01F; Rf = 0,Rr = , v V = 0. (a) V dng sng ra vo. (b) Lp li phn a) nu R = 1 kO, v C = 0,001 F. -58- 1.32Thit k mt mch ghim cho dng sng ra nh hnh P1.17. Gi s t cho sn l 0,1 F v tn hiu vo vi = 5sin25000tV. Cho V = 0,7V. 1.33Chn in tr hn dng LED c chiu sng thch hp bng LED khi t 8V vo LED. p s mt s bi tp b sung c gch di dng. -59-

-60- Cu hi v transistor hiu ng trng 1. JFET l . . . (a) Cu kin n ht ti;(b) Cu kin iu khin bng in p; (c) Cu kin iu khin bng dng in; (d) Gm c (a) v (c). (e) Gm c (a) v (b). 2. Knh dn ca JFET l gia . . . (a) Cng v mng;(b) Mng v ngun; (c) Cng v ngun; (d) u vo v u ra 3. JFET lun lm vic vi (a) phn cc ngc tip gip pn cng ngun; (b) phn cc thun tip gip pn cng ngun;(c) in cc mng c ni t;(d) in cc cng c ni vi cc ngun. 4. Vi VGS = 0V, dng mng s tr nn khngi khi VDS vt qu (a) in p ngng dn; (b) VDD;(c) VDSP;(d) 0V 5. Vng dng-hng [constant-current] ca FET thuc trong khong gia (a) vng ngng dn v bo ha;(b) vng ngt v in p tht knh; (c) 0 v IDSS; (d) in p tht knh v in p nh thng. 6. IDSS l (a) dng mng vi cc ngun b ngn mch;(b) dng mng ti vng ngt; (c) dng mng c th c ln nht;(d) dng mng ti im gia. 7. Dng mng vng dng-hng s tng ln khi (a) in p phn cc cng-ngun gim;(b) in p phn cc cng-ngun tng;(c) in p phn cc mng-ngun tng;(d) in p phn cc mng-ngun gim. 8.TrongmtmchFETcVGS=0V;VDD=15V;IDSS=15mA,vRD=470O.NuRDgim xung bng 330O, th IDSS bng (a) 19,5mA; (b) 10,5mA; (c) 15mA; (d) 1mA. 9. Ti vng ngt, knh dn ca JFET l (a) mc rng nht ca knh;(b) b nghn hon ton bi vng ngho;(c) rt hp; (d) c phn cc ngc. -61- 10. Trang s liu ca JFET cho VGSOFF = - 4V. in p tht knh [pinch-off], VDSP, (a) khng th xc nh c;(b) = - 4V; (c) ph thuc vo VGS;(d) = + 4V. 11. JFET cu hi 10 (a) l JFET knh n; (b) l JFET knh p; (c) c th l c hai loi. 12. Cho mt JFET c IGSS = 10nA o ti mc VGS = 10V. in tr vo l (a) 100MO; (b) 1MO; (c) 1000MO; (d) 1000mO. 13. Mt JFET knh p, VGSOFF = 8V. Tr s ca VGS c phn cc im gia xp x bng(a) 4V; (b) = 0V; (c) 1,25V; (d) = 2,34V. 14. MOSFET khc bit chnh vi JFET l do (a) thng s cng sut;(b) MOSFET c hai cng;(c) JFET c mt tip gip pn; (d) cc MOSFET khng c knh vt l. 15. Mt D-MOSFET (MOSFET ngho) c phn cc mc VGS = 0V. Cc thng s trang s liu ca cu kin l IDSS = 20mA v VGS(off) = - 5V. Gi tr ca dng mng (a) = 0A; (b) khng th xc nh c; (c) = IDSS; 16. Mt D-MOSFET knh-n vi VGS dng l ang lm vic (a) ch ngho;(b) ch tng cng;(c) ngt [cutoff];(d) bo ha. 17.MtE-MOSFET(MOSFETkiutngcng)knh-pcVGS(th)=-2V.NuVGS=0V,th dng mng l (a) 0A; (b) ID(on); (c) ln nht; (d) IDSS.

18. TMOSFET kiu c bit ca (a) D-MOSFET;(b) JFET; (c) E-MOSFET; (d) gm c (a) v (c).-62- BI TP. CC BI TP C BN Mc 7-1 JFET 1. VGS ca mt JFET knh-p c tng ln t 1V n 3V. (a) Vng ngho s hp hn hay rng hn? (b) in tr knh tng hay gim? 2. Ti sao in p cng-ngun ca JFET knh-n cn phi lun lun hoc l bng 0 hoc l m? 3. V k hiu mch ca JFET knh-p v knh-n. Ghi tn cc in cc. 4.Hyvcchmcinpphnccgiacccngvcc ngun ca hai JFET mch hnh 7.56. Mc 7-2 H c tuyn v cc thng s ca JFET -63-