Non-sinusoidal Signal Geneaos ecangle, iangle, saw ooh, pulse, ec. Muliibao cicuis: asable no sable saes (wo quasi-sable saes; i emains in each sae fo pedeemined imes) monosable one sable sae, one unsable sae bisable wo sable saes Fom he sable sae he cicui swiches in he ohe sae unde he acion of a conol signal (inpu signal). Fom he unsable sae he cicui swiches auomaically in he ohe sae.
Asable muliibaos (elaxaion oscillaos) Opeaing pinciple he ime aiaion of he olage acoss he capacio is exponenial ype if he olage acoss he capacio is fed o a PF compaao, a ecangula wae is obained
) ( (0) ) ( e e hh OL OL hl Asable muliibao ecangula signal geneao O D ) (
( ), hh hl e c c e ; c ln OL ( ), 3 hl hh e d d e ; OL d ln OL OL Geneally OL c d ln ln c d If = ln 3.
a) hl hh OL 0 0 0 Poblem ± PS = ±, =0kΩ, =0kΩ, =7.5kΩ and =0nF. he op amp is a ail-o-ail ype. a) Wha ae he minimum and maximum alues fo he olage acoss he capacio? b) Wha is he fequency of he ecangula signal? c) Modify he cicui fo an adjusable fequency beween f min =0.8kHz and f max =8kHz? 4 0 4 0 0
3 0 0 0 b) 04μs 3 3 ln 0nF 7.5k ln 9.6kHz 04 f
c) ' ln ln.386 ' min.386 f.386 f max max.3868khz0nf 9kΩ Selec =8.87 kω (%). max f ' min.386 P P 90k; hecking fo numeical alues ' P 90 8.87 8.3k Selec P =00 kω
How can he asable muliibao cicui be enhanced o geneae a pue iangula signal? In he asable cicui he capacio is chaged/dischaged in a seies cicui unde a consan olage => aiable cuen If one d c can i c se d; c ( ) i c d ( ) i c I cs. c c I esuls a linea aiaion in ime of he olage acoss he capacio o obain a iangula signal, he capacio should be chaged / dischage unde a consan cuen I
Asable muliibao wih an inegao and a compaao ecangula and iangula signal geneao hl o hh OL
d c In geneal If hh OL hl 4 dischage d i i 0 c hh hl hh 4 f 4 hl OL hh d hl ;
Poblem A sauaion he oupu olage of AO is wihin of he supply a) Wha is he ampliude of he iangula olage? b) Wha is he oscillaion fequency? c) Wha is he maximum alue of he cuen o he oupu of each op amp?
Fequency adjusmen i i ange adjusmen: swiching oninuous adjusmen: adjusing he cuen ough O i ( O OL o O adjusable ( +P) Adjus he olage applied acoss )
Fequency adjusmen - adjus he olage applied acoss f max 4 ; f min 4 4 4 P f
he independence of he supply olage Z 0,7; 0,7 OL Z Wha is he ole of 3? he eese-biased base o emie juncion behaes as a Zene diode, egulaing he olage a a olage dependen on he ansiso ype and on he emie cuen (5 8 ).
Offse adjusmen of he iangula olage Based on he anslaion of hyseesis fo he PF compaao. hl a hh a OL amax 5 P a P a 6 6 PS 5 P 5 a 6 3.75 PS
Offse adjusmen of he iangula olage amin 5 P 6 a 6 PS 5 P P a 5 6 3,75 PS he offse can be adjused beween o max 3,75 5; omin ( 3,75) 5 33 33
Specialized inegaed cicuis fo signals geneaion 8038 - Pecision Waefom Geneao/olage onolled Oscillao (iangula, squae,sine, sawooh, pulse) OBSOLEE PODU NE566 - Funcion geneao O, squae, iangula - MHz AD9833 - Low powe, pogammable waefom geneao: sine, iangula, and squae wae. No exenal componens. Fequency and phase ae sofwae pogammable. 3-wie seial ineface. Powe-down funcion (SLEEP). 0 MHz o.5 MHz oupu fequency ange. 555 - highly sable deice fo geneaing accuae ime delays o oscillaion (asable and monosable) - ime
lock geneaos Quaz-cysal f 0 =,, 4, 5,, 0MHz oscillao f 0 =4,388MHz - ideo adape in pesonal compues f 0 =3,768Hz - digial wach, diide by 5 o ge Hz NO gaes oscillao ing oscillao f d n d - delay ime of one ineo