. 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
. deal( ) p amp.. p amp * :, * C p amp :. Op amp grund. *, ffset.
.. 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 :
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 deal p amp bandwdth( )., gan deal p amp gan A ( ) Gan? p amp pen-lp, p amp feedback clsed-lp
6.. dfferental cmmn-mde dfferental, d :., d cmmn-mde, cm :. cm /( ) cm - d /. cm d /.
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.. 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 0 p amp ( deal p amp mpedance, 0),. O O 0 G
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.
.. 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.
.. : A deal p amp..5 clsed-lp nertng..,., ( / )., nertng nput resstance. (. ) Clsed-lp nertng 0.
. :.8 nertng amp gan00, nput resstancemω.(p amp deal. MΩ )..5 nertng. > > 0, 0 0 x x x
MΩ, MΩ.(, ), MΩ.( MΩ ), gan -, 00 MΩ. 0. Ω. k, nertng.5, MΩ MΩ, gan-00 00MΩ.(.)
5.. (weghted summer) nertng. summer weghted n n n f f f f f n n n n,...,, _ _... 0...,,,..., _, > (, n ).
6 >.
7. Nnnertng :. clsed-lp. gnd... Clsed-lp gan: : p amp deal (A ) > rtual shrt. D A 0 >nertng / > (p amp 0) >
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
9.. Vltage fllwer: nnnertng buffer amplfer : mpedance surce mpedance lad. (ltage gan. ) nnnertng 0, unty-gan : ltage fllwer: (fllw).
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.
.. sngle p amp dfference amp..6,. Superpstn prncple( ) :( netwrk lnear, ). ), 0 > :.7 (a),. (Op amp nnnertng 0 > nnnertng 0)
), 0 > :.7(b) Op amp nnnertng 0, /( ). ( ) ) _( _.. _ A gan al dfferent amp dfference e f d d > > / / >,.
Cmmn-mde :.8 0 A cm cm cm cm cm cm cm cm Q
Dfference amp :.9 dfferental d : d (,, ) d d 0 d d, d..
5.. nstrumentatn Amplfer( ) :.6 dfference amp. ltage fllwer. ltage fllwer stage gan. stage dfference functn A d gan : > gan
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
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!
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
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.
0.6. full-pwer bandwdth p amp, S..6 unty-gan ltage fllwer, V snωt. d dt ω V cs ω t
, 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
.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.
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
5 sgnal swng, dc V OS. Dc ffset : ) ffset (ffset p amp ): V OS dc 0..0. ( V OS.)
6 ) capacte cuplng ( dc ):.(a) capactely-cupled nertng. Cuplng capactr dc pen, dc V OS ( V OS ( / )). V OS.(a) untygan ltage fllwer.>.(b)
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 ).
8 nput bas clsed-lp amp dc : sgnal surce grund nertng, nnnertng., dc. V O B B.
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.
0, _, _, _ >, OS : B B OS /, B B OS /, (.5) V O OS. V O ( B ). nput bas p amp dc. (.5 ac-cupled, )