2장

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1 . Operatnal Amplfers (, p amp) analg,, ( transstr, ), 960 C p amp (µa 709), C p amp C p amp : ().(p amp ) () (deal) >C p amp p amp buldng blck,. (C p amp: transstr,, capactr.) Op amp 9

2 . deal( ) p amp.. p amp * :, * C p amp :. Op amp grund. *, ffset.

3 .. deal p amp p amp : ( - ), (gana) ( ) A( - ). deal p amp 0.,, 0, deal p amp mpedance. ( ) deal ltage surce., lad A( - ). deal p amp mpedance 0. (deal) p amp :

4 nertng (, ) 80 nnnertng (, ) p amp dfference sgnal ( - ), (cmmn-mde sgnal) : cmmnmde rejectn. deal p amp cmmn-mde gan 0.. Op amp dfferental-nput, sngle-ended-utput.(, dfferental ) Gan A dfferental gan. pen-lp gan. Op amp clsed-lp, gan clsed-lp gan. p amp drect-cupled (dc). (dc),. (dc )

5 5 deal p amp bandwdth( )., gan deal p amp gan A ( ) Gan? p amp pen-lp, p amp feedback clsed-lp

6 6.. dfferental cmmn-mde dfferental, d :., d cmmn-mde, cm :. cm /( ) cm - d /. cm d /.

7 7. nertng p amp:, feedback. : p amp nertng nnnertng nertng :.5 : negate feedback. p amp clsed-lp. : grund. > : surce,. : ( mpedance deal 0 ). grund lad.

8 8.. Clsed-lp gan Clsed-lp gan G : G O.5 p amp deal G. Vrtual shrt crcut rtual grund A.,, p amp 0, O O _ > _ A 0, rtual shrt crcut.(, shrt crcut ). grund( 0) ( 0) 0. rtual grund.

9 9 0 p amp ( deal p amp mpedance, 0),. O O 0 G

10 0 clsed-lp gan G,. (-) 80.(, (nersn) ). clsed-lp gan nertng. clsed-lp gan (, ), clsed-lp gan. G p amp gan. negate feedback clsed-lp pen-lp gan gan A., gan.

11 .. pen-lp gan : p amp pen-lp gan A. A A > 0, A G A A A A A / > 0 > > > > > > A A G A Clsed-lp gan G pen-lp gan A ( / )<< A.

12 .. : A deal p amp..5 clsed-lp nertng..,., ( / )., nertng nput resstance. (. ) Clsed-lp nertng 0.

13 . :.8 nertng amp gan00, nput resstancemω.(p amp deal. MΩ )..5 nertng. > > 0, 0 0 x x x

14 MΩ, MΩ.(, ), MΩ.( MΩ ), gan -, 00 MΩ. 0. Ω. k, nertng.5, MΩ MΩ, gan-00 00MΩ.(.)

15 5.. (weghted summer) nertng. summer weghted n n n f f f f f n n n n,...,, _ _ ,,,..., _, > (, n ).

16 6 >.

17 7. Nnnertng :. clsed-lp. gnd... Clsed-lp gan: : p amp deal (A ) > rtual shrt. D A 0 >nertng / > (p amp 0) >

18 8 : > negate feedback : > d > >,, nertng feedback > d > d 0... nnnertng Nnnertng gan > nnnertng mpedance : mpedance0 :.. pen-lp gan : p amp deal(, A ) G A >> ( ) ( ) ( ) > G ( ) A

19 9.. Vltage fllwer: nnnertng buffer amplfer : mpedance surce mpedance lad. (ltage gan. ) nnnertng 0, unty-gan : ltage fllwer: (fllw).

20 0. dfference amplfer dfference amplfer :,. : dfferental mde cmmn-mde..5, A A, d d cm cm A d dfferental gan, A cm cmmn-mde gan( 0) CM(cmmn-mde rejectn rat): Dfferental amp ; CM 0lg A A d cm dfference amp :., (mv ) transducer. Transducer gnd (V ). dfference amp.

21 .. sngle p amp dfference amp..6,. Superpstn prncple( ) :( netwrk lnear, ). ), 0 > :.7 (a),. (Op amp nnnertng 0 > nnnertng 0)

22 ), 0 > :.7(b) Op amp nnnertng 0, /( ). ( ) ) _( _.. _ A gan al dfferent amp dfference e f d d > > / / >,.

23 Cmmn-mde :.8 0 A cm cm cm cm cm cm cm cm Q

24 Dfference amp :.9 dfferental d : d (,, ) d d 0 d d, d..

25 5.. nstrumentatn Amplfer( ) :.6 dfference amp. ltage fllwer. ltage fllwer stage gan. stage dfference functn A d gan : > gan

26 6.6 p amp large-sgnal utput sgnal p amp..6. Output saturatn :., p amp. Op amp - V saturatn., 5V, V, V saturatn., p amp rated utput ltage( ) V. peak (clp ff),..6. p amp.(feedback lad < ) ( ) 7 p amp 0mA

27 7 >, saturatn. (.5).5 nnnertng : gan / 0 V p sne wae. lad L. Op amp saturatn V, 0mA (a) V p V, L kω,? 0V sne wae. <V > k! 0V? Lad ( L ) 0V/K0mA feedback ( F )0V/(9kk)mA > ( O )0mA mama <0mA >k!

28 8 (b) V p.5 V, L kω,? : 5V >V> V saturatn (.5(b)) : L V/KmA, F V/(9kk).mA, O ma.ma.ma <0mA >k! (c ) L kω, sne wae V p? V p V/0.V..mA <0mA ((b) ) (d) V p V, sne wae L? 0V. O 0mA 0V/ Lmn 0V/(9k k) > Lmn 56Ω

29 9.6. Slew ate -, slew-rate lmtng. p amp slewrate (S), ( : V/µs): S d dt max p amp, S, p amp, S. :.6 unty-gan ltage fllwer.6(b) step, p amp V,.6(c), S lnear ramp. slewng, slew-rate lmted.

30 0.6. full-pwer bandwdth p amp, S..6 unty-gan ltage fllwer, V snωt. d dt ω V cs ω t

31 , ωv, (csωt). ωv p amp slew rate,.7..7, p amp slew. Full-pwer bandwdth, f M : p amp rated slew-rate lmtng., V max rated. ω M V max S > f M S πv max

32 .7 DC p amp dc gan drect-cupled deces DC..7. Offset Vltage: p amp gnd ( 0). ( Op amp stage dfferental amp msmatch.), 0. ffset V OS. ffset p amp : Clsed-lp p amp nput ffset ltage V OS.

34 p amp V OS 5 mv,, V OS. Op amp V OS : nertng, nnnertng surce shrt p amp.8.9 ( )., V OS dc. V O V OS, clsed-lp gan 000 nnnertng 5mV V OS p amp, dc 5V 5V., 5V dc., allwable

35 5 sgnal swng, dc V OS. Dc ffset : ) ffset (ffset p amp ): V OS dc ( V OS.)

36 6 ) capacte cuplng ( dc ):.(a) capactely-cupled nertng. Cuplng capactr dc pen, dc V OS ( V OS ( / )). V OS.(a) untygan ltage fllwer.>.(b)

37 7.7. Bas dc. bas : p amp dc.. surce B, B.( p amp ). bas, B : B, B., B B B B, B nput ffset current OS., OS B B BJT p amp B 00nA, OS 0nA. MOSFET (pa ).

38 8 nput bas clsed-lp amp dc : sgnal surce grund nertng, nnnertng., dc. V O B B.

39 9 nput bas dc :. p amp,.( )., V O. V O B B B (.5) B B B, V O. V O B, V O 0.

40 0, _, _, _ >, OS : B B OS /, B B OS /, (.5) V O OS. V O ( B ). nput bas p amp dc. (.5 ac-cupled, )

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½½¶óÀÌµå Á¦¸ñ ¾øÀ½ 0.2 완전차동 (fully dfferental) OP amp Dfferental nput, Dfferental output Easy to cascade OP amps nsenstve to supply nose Hgh gan Fully dff OP amp requres CMFB Hgh Speed CMOS IAB, POSTECH 0.2. NMOS 입력완전차동