Điện Tử - Cơ Sở Thiết Kế Mạch - Design Trên Máy Tính (Phân 2) part 16 pps

IrCIl c1ulmg lin hi~ll g XU... Them vdo do m¢t diem yeu ella m6 hlnh loi hang so lit m6 hinh 16i nay kh6ng phan unh mlt each day du.. Bili tmin phat hi~n l... Trang djnh nghii.l I1llY eh

Su 11(\ lll'.lcl1lfcn m{)t dlf(l'Ilg lin hl\'U c6 rc nh<inh co lile ~inh ra nJlI~lI 161

llang ,() lr~ll de nh<inh Illanll phiin (\'i d~l nilLr Ircn hll1h X,I h), t\'Cli ell! gi6i h;,lll nglucil eCru lll(l hinh 16i klng s(} ehm le ebling, I'l pli,'u XI.!Ill xcI JllO! J()J

h,-lllg ,Il d(in k Ircn e;ie nll<inll rC' eLLa dw\ng 1In hi\'u laeh bi~1 \,t'J'i ](ll uen llh,inh ehinh

Kili 1:\ Ilwe Ill~ll mil hillil l](l,i lll',lch lil-:o ILl'llg hU(l'c ph:'lll c,Yp mell Ih;mil

ph;'ul mach ,,0 dlH/C hicu tiil.'ll Ihc() c[le lllt1 Jdnh c;fu Inle ])':n Iron,:! ella ehLlng Tuy Ilhj~ll nc'u C<Ie Ihi'lllh r,\],\ll m;.lCh dUl.1C kicm Ira d{lC l<:lP Inn'rc kill clll'lJlg dU\K bp r;ip klli ell) eheing la chi dn IhlC'1 ].;iemlra c<'le Ihi ,'l11il ilUCillg

IIl'1 de dlr(\ng ],;0'1 nt)! gala de pll,ln ILf d() : JIll! \,(Iy chung la '>c ]';hllllS XCIl1

\l'l etc loi xU,ll hl~ll b':n IlOng c,\c Ih;lnh ph,'l1l ll1;,lch m;1 chi gJ()'i h:,ln \'lCC kh:lO "'[11 de ll\i gt!!J \,{ri de eh:1Il \';IO!ra eLl,[ Ih;mh ph{in lil,i Ihicl n:' gil)'j han etc j()i 1;.li Ch:1l1 \";'IO/ra g(.ll 1:\ /11(1 lIillll !tIl I~/; (Jlilll nio/w Sal! c1:1Y elll'l1lg 1.1 XClll XcI 1l1l)1 6 \'1 dl,l \'C :lIlh hu('jug ella dc d • lng 16i n()i Iren dC:Jl ehLre

J],-lIlg ]()gle ella de lll',leh

Trollg c<ie lll:.lCh j()gic kli h;\ng S() 1;.161 hay g'~lp Kill IrCil m()1 dlJ'(\ng tin

~ -c (.r I· \ )+1I'+(.\"-; y) =x 1.\ '-II'

Inuh KZ Vi du '-0 dll m,ldl 1().~1L"

l1i\'Ll (/ XU:!I hi¢1l It'll h<'lllg S(l yil I.-Ull ello gi,i Iri I III hicu e(i d!I1h h;'lJl),! k 1111 It'>i J1;l~ '>0 dL(,l"C glH 1:'1 I(\i h:"IJlg sli gi,i II"! k \';\ dU\K' hi'::u dlCIl Irl'll ~()' d6 In'.ldl LI

(ill T.l h~ly X~I \"i eh.! m;.leh Ir~n hlllll S.l

\'':'-u lrong m'.lch c61(\i htlng s6 d/l Ih] d~iu ra ~ sC' b! Ihay d6i Y;'l It;'ull ra

Cll.! 1ll;'Ieh ,>0 h;\ng:

- - / (\\' r 1'1 - .r + \'

- - II , _ -Tmng IfUlf!lg hqp c() Ibl h~lllg s6,' :/0 Ih] h;Ull ra s0 h;\ng:

~ ==.(jll' cy) ==.1 + -" + II'

Ilillh KZ Vi du lil.lch lllgK

t\·.:'u c.ie 16i h[l1lg '>(1 XU,t'l hien Irell c1ucmg lin bicu (()

rc nh:ulh la dn clui 5' xcI

;lllh hu/mg lall nhau ella ute loi Iren Gic rh~11l nh:lllh eLLa dUlfIlg lin hi¢u, Nhu I["ong \,( dy In:n IrCIl c1ulmg lin hi~ll g XU<t"1 hicn il)! g/f), \':m d~ d:,ll ]';11:1 Ibl

\li\\' c6 ,'tnh hu'('mg l6'i dui\ng lin hi¢u k kh()ng, Trong mt)1 "0 Inrcmg hq'p nCLl

chi :\~II()'i C"IC lien k0"1 giG'a dlc c1u'ong lin hi¢u IhI111()t deh IV nhiC'n, [(li Sj()

"e,; g.\y ra [(}i k((): nhung ne'u xci Ircn quan c1iem \'[11 Iy Ihl di':u d6 Kh(lll~ eh~\c

chtlil N(li chung de (tim bao Iinh 16ng qUilL chung la dn ph:li gl<l t[u0"1 rtmg

[(\1,' ;/0 vii k/IJ lil nillrng It)i Kh.IC nhau, Nhu v,)y, Irong Inri:ing IH,1]1 IrOll!; mach 'd.l:I't hlcn 161 k/I), h~\ln ra '>(: cho gi,i Iq :: biing:

::=/;",(\\',.I",y)= \\' .rr*(1i Trong lnri:l'llg hor nil)" h:l111 ra Kh<.lc \"(')'i trlfimg h<.1'p I(\i gj()

Tr{lng Irl((\ng hop lrollg 1ll',ICh xUllt hlcn \(')i ej() m(ll ccich [ll" nhiC'IL dLli1g ta ct'i [hC: c~li Itli nilY l2t I[q) h(JP clla hai It'll g/() vii k/() l\11ll' \',:IY chLlllg

ta thClY c() sv ph,11l nh<.lnh \':1 Ian Iruy(!n [/)i Ih.:o c,ie dl((\ng lin hi¢u lien KC"L Tr'1m L.li t-.hi c(l ,,~j' phfl11 nhilnh du'('mg lin hl~lI eilling la c:ln ehu )' [l)'i nhu-ng khi\ n:lllg phal sinh 16i [ren C"IC nh[lI1h "il l hei n,-Illg xCI c;ie c1u'(\ng lin hieu phil]} nh;jnh: Ule clu'bng tin hi~'u n~lln sall diem rc nh<.lnh c6 the dlfl,ie coi Iii llhCl"Ilg dlflYilg IIIl hi~u kluic nh<lu, hO~lc tAl cii nhtlng (h[,\ng tin hlCU hcn J d nii llhau e6 Ihe duU"c coi !iI ellllg !l1t)t dui:mg:

f3i"IY gl{) ChLlIlg 1<1 xCt UIC j()i c11;)p mach t\hlf Iren dJ dc qp ({"Ii 11'011:;

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,~~~£p-'-I

llillh N,.' Ul[ Il.lL' l';lll \:'-l1)1 l'-d I ;"lI~\l

Ill":[lllll[):; 1Il:ldllll'nliillh::-; 2

nhiC:u tru'('jng hop Ceil' h\i eh')[1

m<'lch I'.H) llC'1l nht:rng h\i bflc dill V~I dUnc d~lc Inrllg h('jl

\'i¢c thue hlen dlc 11:1111 [(\glc A0JD h()~le OR Khl IrOIl);

m'.lch dl sl.l" ch,\p hal dU(\Il)l

tin hl¢U <I \':1 II \'il '-;lIlh ra CiIl'

h\1 hell' C~lU lLrU"llg Cfll,:'- \'(\'j

de h~\lll \('lgic m;1 ChLlIlg Ihe hlcn [;\ AND !JO;IC OR dlc h\i n;IY s0 dune k~' 111cu \Uung ling 1,\ Al\D(a-h) OR(iI-b) Ta h:IY X~I \"I du mach IrCIl hillh X,2 nClI dlf(\ng lin hi0u (" va II b! eh:'!) "il sinh ra [(Ii dl,:IP Ill'.ICh htIC du AND( c-d ) hi\ll1 ra ,,;: ell lL.ll1g nhu S;IU:

f"\"iJ/,.,,/II" r,yJ ~.I" + .\y + II" Y + .1" \\'

r-,.·1(ll Irong nhCrng hili to{Ul co" b,'lll g:~n licn \'(')'i m() 111nll It,i [(lgie [il 11','\ [(\i

C,'ILI h()i: m{l hinh [{li [(lgie c(l Ih~ ph"\ll {Inh cae [()j \'{II I)' xu.11 hi~'n lrong cie

mach \'6i d() trullg tlure 1l~IO -Dc U) Il lC nhi~n tlwJc Slf Ilfong uHg m(ll deh

kh.ich quan \'l)'i dc l(\i \"(11 I~', ch(ing (,hI ph.ii Ilghi011 etill m(ll sCi !u\mg kill e,le mo hinh it'll [()gil' Nhung Ull d(") m(ll kh(") kh,-m g~lp ph,li 1;1 dlCLI n;\y 1:1111 elm de Ihll.lt lo.ill t<'IO ciic bt'l giii In Ihlf nghiC'1ll dLIllf! de ph;11 111cn [ill Irii

2 1-9

ncn phuc tap han nhi~u Doi v6i m(lt so m6 hlnh It'll logic nhu mo hinh 16i

h:lIlg so, vi¢c tao d.c h¢ gii tr, thu nghi~m de phat hi~n 16i wong d6i dan gian Them vdo do m¢t diem yeu ella m6 hlnh loi hang so lit m6 hinh 16i nay kh6ng phan unh m(lt each day du cac dij.c t[nh clla cac loi \,\It \)'

§8.2 Bili tmin phat hi~n l<"Ii

Trang ml.lc nay chung ta dLIa ra mQt so khai ni¢m ve hili Imin ma hlnh hO<.i l6i va phal hi¢n 16i trang dc nwch logic Vi chung ta chi a cac mi teh logic lam hai nhom: de m;;teh 16 hqp va d.e m<.lch tuan ttl d~ra theo hanh vi hm.tt d(lllg clla m'.lCh Ci.c 1m.1i m,~ch nay co diem khiic bi¢t d Sl! ton li.ll eua

bQ nho va vong phan h6i Do d6 cae phuong phap li.to de bQ gia Iri tht'r nghi¢m d6i v6i hai Im~i mi.~ch noi tl'en cung c6 nhiIng ditm khi.tc bi¢t Chung

ta sc xet ricng tung 10<;1i m~ch; mqt so phuong phap su dy.ng eho cae lmwh tel hqp ding co the phal tricn sang tru'ong hqp de mi.tell tuAn t~l' veli nhung slJ'a doi Ihich hqp

1 Pilat hi~n loi trung cae m~ch to hlJp

a Bai toan ph at hi~n U)i

Cho Z(x) Ii! ham logic clla mi.lch 16 hqp N v6i x la v-:cw gia tr! dfill \,~IO

hAl ky vA Z(x) bieu Jien anh Xi.llhy.'c hi¢n h6i m~\eh N V6i m(ll vce\(1 gi[l tl'! dfiu VilO ql the t = ( x t ,x 2, ,x l1 ), ta se c6 Z(t) la dip ling dta m,:!eh N doi \'oi vceta t Doi \'6i nhiIng mi.lch co nhieu d[iu ra, Z(t) cling lit vec10

Neu trang mi.leh xuat hi¢n 10iI, mi.lch N se chuycn th~mh I1li,1ch Nt Ta gia Ihiet r:mg m;.lch N j c(jng lit lm~eh t6 hqp "oi ham ehuc n~\I1g Z/x) Mach dU'<;1e

kie'm nghi¢m btlllg each d(lt day T eu.a cac veetlJ gia tl'j thu nghi('m t 1 ,t 2 , ,t,,,

len c:.i.e d~iu V~tO eua m,;lCh va so sunil nhli'ng gia Il'i thu duq'c tl'en Hu ra theo

Iy thuyet eua nweh N tuang ling v6i nhling vceW dfiu "ao do: Z(lj)' Z(t2)'"'' Z(t",) v6i nhO'ng giil tf! thu dUQ'e lren thl!e Ie

Chung la dua ra dinh nghia nhu sau: vceta gia tf! kiem nghi~m t duqc gqi lit phat hi¢n 16i f neu: Zj(t) 1:-Z(t) Khi ap d~mg dinh nghia trcn, chung la phai chu y nhi1ng diem dutii day:

Ciie veeta gia tfj ki6m nghi¢m trung day Teo th6 dUtJ'e su: dl;!ng kh6ng plW lhut)e 'laO trlnh tl! ap dL.mg, doi voi IlWeh 16 hqp N, day T dU(;iC gQi la I~p hqp cae vccto' gia tr! h~'m nghi¢m

Djnh nghla 11;'Y kh6ng ap dyng duqc neu m,!-eh ehua 16i N, trl11htHlh mach tufln t~r

Trang djnh nghii.l I1llY ehung ta gi,\ thiet n'ing vi¢e ki6m tm loi b,\ng each d~lt cae gi<.1 Iq Ihu nghi¢m va thu nh~Hl cae kc"! qmt th(mg qua de

eh~1Il clla ph tn tu Va so siinh hoilll toan eua de ket l}lt<i nh~n du·qe Chung la xac djnh h~lill:

F,(t} == F/x"x! x,) = Z(x/.x 2 •.•• x,,,) EB Zrr/,X:"",xl/) t\'lm v('y, neu Z(t) -:;t; 2

1 (t) ta sc eo F/(t) nh(U1 gi[L tr! 'I '; con neu %(t) = 21(t) b511g nhau, lue IiI F/f} nh~n gia Ir! '0', la noi rUng veeW giil trj thtl." llghi~m t

kh6ng ph~t hi¢l~ duqe loi f Ham F/t) eon duqe gQi la ham khoJ.ng each 10i Veeta gia Ir! dau vao 1 = (X I'X2 • • x,,) lam eho F/t) =1 de phat hi¢n duqe loil

va gQi Ia vceta gia Irj kiem nghi¢m plutt hi~n lc\if

Ncu trang 111<.,\ch co p 16i viI ncu 1',//), FAt) , , FI'(t) la de ham khmlng deh WOJlg lrng \'6i tung loi, khi do de \'ecW gi,i Irj hem nghi¢m de pllL!t hl¢n nhil"ng Ill! do duqc 1,.10 thanh t(lp hqp:

,-,

T(lp hqp BtlY g9i Iii h~p cac gi[l Irj kiem nghi¢m de phat hi¢n 16i

Ta hay xct ll1<)t \'i dl;!, trC:n m~.lch hinh 8.4 xuilt hi¢n Il)ij"El 10i bAe c:iu OR

Z

0<

"

Z,

101 biic cau )(jgic OR

gilra hai du6ng tin hi~u '\"/V~I x 2 , Loi hAc C,ill n;IY

dua de ham ra ri.ti ZI va 1:2 tny thanh:

L2/= (XI +x 2 }x( (thay choZ1 =X2.\"3) Veeta gia tr~ di.l.u va~ t = "011" ello· phep phat hi¢n loi nay VI vceta gia trj d:iu fa kili mach khCmg 16i bitng

1:(011 )=01 trang kill do khi XU;}t hi¢11 16i l

Z,(OII)= II, Nhu V(IY, la co Z( I) -:t:-Z/ t) viI F, (t) = 1

251

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L-f l

',~ -l

G3~ ~_~ G5 Z

G4

-Ilinh 1t5 Vi till \'~ ](li hillll" ,(l 1',/1)

Ta :\0t tl10m vi dL,1 \'C CC\c [tSl him,S ~l-i dlii \'(ii lll<,ICIl

tr0n hl11h ~ 5, M'.ICh n:\v

tln,re hi~n h:lI11 16gll":

Z=(.I.+,r,J.I, + ·1'11':

(Ii;\ t[Het rClng trung mach :,\Uil't hi0lJ I,\i lI/lIlg

~(i r !;!I<ltri '0' .\"u-() tn~n dU'(\11g <10.\ ( \(ll _ljO ) V(i'i "V .'\ll~lt hi0n ella [(li "Ij(), t.1 IU(')ll d) 1", \~ = I \'~\ h:ll11 fa 1 • 11 ltLl(~IIg : Ira' Ih;1Ilh: ZJ = ( r: + Xi ).1 1_ DICU ) 1~ll ph,it lli0n Itll

Nllu "[IY mOl \'ceW gi.i In dCILl v;\o c6 x' \'J x ~ " Iho.\ 111;111 (ti\5u kll':'n In':'1) - ILK

Ll .1'1 = () v;\ r.i = 1, 1:1 \'ceIO" gi;i tq kicll1 nghi~m ph;!1 11101\ I()i .I,m Suy ra

"Celo' ,gitl II! kicmnghi01ll ph(tt hi~ll [OJ x)O ctllhc b m()1 trung 11hCrng \'l'ClO'

sau:! OIiIlUIOI UIIIII, 01 I I),

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o

1

Gl

-r'~

G2

0/1

G5

0/1

,

\':1 quail "at 11;\1111 vi clla m.Kh 1J'llllg tnr(l'llg hop

)"'hll!l,l! c(i Ill! \'::1 U'l Ill[ C() lImh \ u-l [ren d:iu

ra ella ph:lll III (;, 1'1'011 I1lllh I'e dll'a ]''1 gi;i Ir! lin

hll:U Irl:ll eic dUll'llg lin

hi~'Ll Imllt:'- h,li IrlnJ-llg

hop kh(Jllg I(li \'~\ c6 Ii)i dU(ii dang l'i1'I' IIOllg dl') \' 1::1 nhi:illt:'- gi-i II'l ItHing (l'Il~

\'(ii Inl'(\ng hop kh(mg Ihi \':1 I', - ((1 I/)j iJli dll\ic ph;il 111\'11 Ill:n d,'ltl ra gi,i 11'\

\'=() -I \', = 1

Vi dlt In'n Ill1n11 h()~l hal kh;ii 11~1ll C(i ~l'i lroll~ kll \O;ln ph;il 1l1l'n kll ella

ell' Ill,.ICh \()gll':

Vccto gl~i Ir! kiem nghicll1 f dLlllg de ph;ll Iw:n l()i r dJ J icllllO'_11 ](ll I

Irllng 'IU~1 Irlnll m() pllong ( c{)]} e6 Illc n6i Et J I[('ji 1'.10 I(\i hO;lC Ll(l

Ili.:u l'lll,!! l\li ) b;\ng c.ieb lao ra nllll'llg gl;l In J h;lC llhau \', "I Ir':ll de dU(J'ng (In Incu tinh Ill' \'1 Irl kll

VCC\(i gl.i II'! kicll1 nghiclll t Iniy~n 1()lflCii drlU rall' \'~t Lun eho Ll'l CI nht:fng c1u(mg IIll hicll Iren il nll:ll 1l1()\ du(\ng lL\n glLl"a \'1 Irf b1 lUI \-:1

d:iu fa 11 ph,u c6 nhCfng gi.i Iq \' d \',' J IHic nllall Trong \'1 Lit! IrCll hlllh

8.6 kll dW,ie Inly~n Ihl'o dLfiing qua de ph,-tn II'r ( (;~, (;-1' (;~),

DLrlHlg IrllY~ll h1 \'ccLo' gi.i Ir! J IClll nghi~l1l t Ihay (kil gi,i Iq klli \u:II hien Illi f lrong Ill.,lell gm EI m.ln C,\Il1 \'()-i kH.I qua \'LClll' J IClll Ilghl~l1l t Dtri)ll,!!

ci.\n c1uqe 1,10 h('ii nlllIng dLr(\ng m,lll dll11 ,~ dune goi 1:1 du'img lUll m.\n elm, )lh,-ill IU [(lgic c6 d:lll ra m[1l1 dlln \'6i I(\i.l ,;: e6 il nh:il m(ll d.-Ill \':IU CC11lg

du'(ye blll eho m:lll C,-I1l\ \{ii ]i)i /' eic gi.i Ir! d,m I', \';1 gi.i Ir! d[~Ll J hicll \', nu pll:in Ill' \()gJC t\I\D, OR, ~A~[), :-';01{ C(') [hl: dWfl' Ihe hl~'ll nlltf ""\ll:

(il,i In d:lll \ilo du\1"l' g~)i b gi,i 11"i dll:U killen \' ne'll gi,] Iii d6 "IC

dPlh ltiU m ella p!J:lll ILr kh{lllg ]111l.1 l!Jll(JC \':10 e.ic d:lU \';\0 kll,ic (;i{l tr, (11.10 )',: C~Il' phclll til' 16gic And Or, l\and ~or nlu:lIl (:.1(: gi~i tr, d~io 1', vil gici tri dieu khicn I', nhu trong InIB:": sau:

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tkjj y(,'j de ph:in 11'[ (()gil' CO' han 1£1 And, Or, ,'\and, Nor, gl:l tri

d:'lt ra dul,l'C tinh theo e.l<: gi:l tri d,IO \'; g;i:i tri di(;u khil"n ,a

h;'lllg ", 8j ""

1\1lll' \'(ly, 111(,)[ ph~ill ll'l' l(lglC \'('ii :; d:lu do "'0 c6 Ciic J h(ii CO' 'i('i nlHr ~all:

\ 8j \' , ,

\' CD \' , ,

.\ X \' \' 8) \' , ,

\' \' \' CD \' , ,

V('ii deh bicll dlen Ih(lllg qua Cite gl,\ Ir! \, \'~t \'" lll~llh de \,(; Illlh 1lI:111 cam \,()'i ]()i ella e.ie pll:'inlLr logic c(ilhe dliq'e ph;ll hlCll nllu sau:

iVlcnh dc YC tinh man cam Illi

Cho G la ph,in tLr logic w'1i gia Irj nghjch d,IO \', vii gia Ir! clieu kluen I c6 d<.tll ra nlwy cUm \'('1i 101 I (lUang ung vai vecla gia tri, kic'm nglli~m t phal

hi~n loi), la c6:

Tdl d cdc driu vao ella G man dm voi loi.f sc nh(tn cung m9t g!a Irj (VI du iii a)

Ttlt eil nhO'ng d lu dlO eLla G kh6ng m;.'tn dm v6i 16i f (n2'u it nhiit m()t

diu vao ll~iO do) se nh~n gia td v"

Dilu ra ella G se nh[m "ia tri (/ c EB \' ,

Cluing minh m~nll de vc tinlt man cam Ibi

,

-Chung ta cllling minh m¢nh de

phuang phap phan ehCrng nlllr sau:

lllnh R.7 Plulnllr NAND

Gdl thie! rung e6 hai (![iu V~IO nil;\)' cim voi 16i trang ph~in lit G Iii J,:, , Cie cHill \':lO

nay nh(lIl de gi{l Iri kh,ic nhau vii gi,-'t SLr drill

vao J,: nh~n gia tri c1icu kllien ella phfill lu: \'" Khi Iren ph[in Ill' XUiYt hi¢n 16il; hai dUll'ng tin hi~u k va I Ihay d{}l g);l Iri vii dU'ong I nh,)n gi,i tr! dicu khi(;n Nhung dicu nay e6 IlghT<l 1:1 pilun ILr G v;'in nh,)n gia Iri eil, dQe 1(lp vai ~I! xu[!! hicn ella 161 r Biell nuy muu Ihuttn voi giil thiet dau ra ella G phAi m;'in dill \'6i 10] - ICre

I~I ph:li Ihay d()i giti Irj khi lrang mi leh xutil hi~n 10] f Nhu' \,~Iy I,'l! C'I

nhu'Jlg d:iu \,~IO mtll1 d!n ella G dn ph;ii nh(trl cung 1119t gi,i tfj ( vi d~l

B:iu ra ella (i kh(mg Ihe thay d()j khi xu,Yt hi~n loilncu mQt trang cae d~iu \,;10 kh6ng nh'-.Iy cam \'o-i loi f nh,)n gi;j II"! \',; do do lat e<"1 de cUu V~IO eLw G khong nlWY dm \'6i Jili f ( neu -.:0 ) dn ph,'l1 nh[m gi,i trj \','

Nc'u u = \'" d,-Iu ra eLla pldn tu: 16gie nh~1ll gia Ir) btmg I', EB I', :"i~'u

(/ = \', ' I[it d cae d[iu V;'IO eua G :-.0 nh,)n gia Iri I', va do d6 driu ra

eua.pllau Ilf siS nh~Hl gia Iri bang I', EB I', Nhu V(ly, trong d hai trLr('J'ng hQ'p d:iu ra ella ph,-IIl tu 16gie G dell llh,)n gia tr~ bAng a EB 1'/