Active Filter vs Passive Filter
Cov lim dej yog chav kawm ntawm cov hluav taws xob hluav taws xob siv hauv kev ua cov teeb liab, tso cai lossis thaiv cov teeb liab uas xav tau lossis teeb liab. Cov lim tuaj yeem faib ua ntau theem raws li cov khoom, xws li nquag - passive, analog - digital, linear - non-linear, discrete time - nruam sij hawm, lub sij hawm invariant - lub sij hawm variant, thiab infinite impulse teb - finite impulse teb.
Cov lim dej nquag thiab tsis muaj zog yog qhov sib txawv los ntawm kev ua haujlwm ntawm cov khoom siv hauv cov lim lim. Yog hais tias ib qho khoom siv siv hluav taws xob los yog tsis muaj peev xwm nce lub zog, nws yog lub npe hu ua passive tivthaiv. Cheebtsam uas tsis passive yog hu ua active Cheebtsam.
Ntau txog Passive Filters
Resistors, capacitors, thiab inductors txhua tus siv lub zog thaum lub sijhawm tam sim no dhau los ntawm lawv, thiab tsis muaj peev xwm nce lub zog; Yog li ntawd, txhua lub lim RLC yog lub lim dej tsis zoo, tshwj xeeb tshaj yog nrog cov inductors suav nrog. Lwm tus yam ntxwv tseem ceeb ntawm cov lim dej passive yog tias cov lim tsis xav tau lub zog sab nraud rau kev ua haujlwm. Lub input impedance yog tsawg thiab cov zis impedance siab, tso cai rau tus kheej tswj ntawm voltages tsav lub loads.
Feem ntau, nyob rau hauv cov lim dej tsis zoo, cov khoom siv thauj khoom tsis raug cais tawm ntawm lwm lub network; Yog li ntawd, kev hloov pauv ntawm cov khoom thauj tuaj yeem cuam tshuam rau cov yam ntxwv ntawm lub Circuit Court thiab cov txheej txheem lim. Txawm li cas los xij, tsis muaj kev txwv bandwidth rau cov lim dej passive, tso cai rau kev ua haujlwm txaus siab ntawm ntau zaus. Nyob rau hauv qis zaus lim, cov inductor siv nyob rau hauv Circuit Court nyhav loj, ua rau lub Circuit Court bulkier. Yog tias qhov zoo dua thiab qhov me me yuav tsum tau ua, tus nqi yuav nce ntxiv. Cov ntxaij lim dej Passive kuj tsim cov suab nrov me ntsis, vim yog lub suab nrov thermal hauv cov khoom. Txawm li cas los xij, nrog kev tsim kom zoo no lub suab nrov tuaj yeem txo qis.
Vim tias tsis muaj teeb liab nce, lub teeb liab amplification yuav tsum tau ua nyob rau theem tom ntej. Qee lub sij hawm tsis xav tau amplifiers los them qhov sib txawv ntawm qhov tso zis hluav taws xob..
Ntau txog Active Filters
Lim nrog cov khoom xws li kev ua haujlwm amplifiers, transistors, lossis lwm yam khoom muaj npe hu ua active filters. Lawv siv capacitors thiab resistors, tab sis inductors tsis siv. Cov ntxaij lim dej nquag xav tau lub zog hluav taws xob sab nraud los ua haujlwm vim tias lub zog siv cov ntsiab lus tseem ceeb hauv kev tsim.
Vim tias tsis muaj inductors siv, lub voj voog yog qhov sib zog thiab hnyav dua. Nws cov input impedance siab thiab cov zis impedance yog tsawg, tso cai rau tsav tsis tshua muaj impedance loads ntawm cov zis. Feem ntau, lub load yog cais los ntawm lub internal circuit; li no variation ntawm lub load tsis cuam tshuam cov yam ntxwv ntawm lub lim.
Lub teeb liab tso zis muaj lub zog nce, thiab qhov tsis xws li nce hla band thiab txiav tawm zaus tuaj yeem hloov kho. Ob peb drawbacks yog nyob rau hauv lub active filters. Cov kev hloov pauv ntawm cov khoom siv hluav taws xob tuaj yeem ua rau muaj kev hloov pauv ntawm qhov tso zis hluav taws xob ntau qhov ntau thiab qhov ntau zaus raug txwv los ntawm cov khoom siv hluav taws xob. Tsis tas li ntawd, cov lus tawm tswv yim siv los tswj cov khoom nquag tuaj yeem ua rau oscillation thiab suab nrov.
Qhov txawv ntawm Active thiab Passive Lim yog dab tsi?
• Cov lim dej tsis zoo siv lub zog ntawm lub teeb liab, tab sis tsis muaj hluav taws xob nce; thaum cov ntxaij lim dej nquag muaj lub zog nce.
• Cov lim dej nquag yuav tsum muaj lub zog siv hluav taws xob sab nraud, thaum cov lim dej tsis muaj zog tsuas yog ua haujlwm ntawm cov teeb liab tawm tswv yim xwb.
• Tsuas yog cov lim dej tsis txaus siv inductors.
• Tsuas yog cov lim dej nquag siv cov ntsiab lus kike op-amps thiab transistors, uas yog cov khoom nquag.
• Theoretically, passive filters tsis muaj kev txwv zaus thaum, cov lim dej muaj kev txwv vim muaj cov ntsiab lus nquag.
• Cov lim dej tsis muaj zog muaj qhov ruaj khov zoo dua thiab tuaj yeem tiv taus cov dej ntws loj.
• Cov lim dej tsis zoo kuj pheej yig dua li cov lim dej nquag.
