Tam sim no, Lub Hwj Chim thiab Kub Kub nce
Cov inductors feem ntau tsis suav nrog lub zog, txawm li cas los xij, kev kwv yees ntawm lub zog tuav lub peev xwm ntawm lub tshuab cua lossis ceramic core chip inductor tuaj yeem kwv yees siv cov ntaub ntawv qhia tshwj xeeb rau tam sim no thiab tsis kam.Piv txwv: 1 μH, nti inductor hasan Irms rating ntawm 48 {{ 13}} mA thiab qhov siab tshaj plaws DCR ntsuas ntawm 1.2 Ohms. Qhov ntsuas Irms sib haum mus rau 15 degree tempera-ture nce siab tshaj ambient. Qhov siab tshaj plaws tau tso cai ambienttemperature yog 125 degree, yog li 15 degree qhov kub thiab txias tso cai rau qhov siab tshaj plaws qhov kub ntawm ~ (125 + 15) {{10}} degree .To kwv yees lub peev xwm, xam Irms2 × DCR . Yog tias peb xav tias qhov nominal DCR yog 80% ntawm qhov siab tshaj plaws DCR tau teev tseg, kev suav yog: (0.48 A) 2 × (0.8 × 1.2 Ohms)=0.221 W=221 mW.Yog li ntawd, kwv yees li 221 mW ntawm lub hwj chim ua rau qhov kub ntawm qhov inductor no nce ~ 15 degree .Thaum RF frequencies, ESR ntau dua li DCR.Yog li ntawd, tus nqi ntawm cov tam sim no uas ua rau qhov kub thiab txias nce yog txo qis. Piv txwv li, yog tias lub teeb liab RF yog 100 MHz, ESR ntawm inductor yog 8.14 Ohms (yuav luag xya zaus ntawm DC tsis kam) sothe Irms AC tam sim no uas sib haum rau tib lub zog (thiab yog li kub nce) tsuas yog ~ 161 mA raws li opposedto 480 mA qhov ntsuas ntawm DC. Qhov kev kwv yees no tuaj yeem ua yuam kev yog tias muaj qhov poob tam sim no nyob rau hauv inductor lossis lwm yam kev poob ntawm cov zaus ntau dua uas tsis yog ib feem ntawm qhov ntsuas ESR qis tam sim no.
Lub zog dissipated los ntawm inductor
Lub hom phiaj ntawm lub inductor nyob rau hauv ib tug bias tee, raws li qhia nyob rau hauv daim duab hauv qab no, yog muab ib tug DC bias rau lub amplifier thaum thaiv cov high zaus RF teeb liab los ntawm kev nkag mus rau lub DC qhov chaw. Qhov zoo tshaj plaws, txhua lub teeb liab RF siv rau qhov kev tsis ncaj ncees lineis lim tawm los ntawm series inductor. Rau qhov kev sib tham no, weassume ib tug lossless (xws li cua core los yog ceramic core) induc-tor uas tsuas yog (AC thiab DC) tooj liab losses - nocore poob.
Tag nrho DC fais fab dissipated los ntawm inductor yog: Pdc=Idc2 × DCRThe tag nrho AC zog dissipated los ntawm inductor yog: Pac=Irms2 × ESRwhere: Idc yog DC tam sim no los ntawm inductor.Irms yog qhov Qhov loj ntawm AC (RF teeb liab) tam sim no dhau los ntawm inductor (yuav qis yog tias lub inductor yuav luag zoo tagnrho).DCR yog DC tsis kam ntawm inductor.ESR yog qhov ua haujlwm zoo ntawm cov inductor ntawm zaus ntawm RF teeb liab (xws li tsuas yog ib qho kev ua haujlwm zoo). ib leeg RFfrequency).Cov tag nrho (DC thiab AC) lub zog dissipated los ntawm inductor yog: Ptotal=Pdc + PacorPtotal=Idc2 × DCR + Irms2 × ESRAs qhia, nyob rau hauv cov ntaub ntawv yooj yim tshaj ntawm ib zaus AC teeb liab Nyob rau ntawm RF kab, txhawm rau txiav txim siab AC fais fab dissipated los ntawm inductor, ESR ntawm theinductor ntawm RF zaus, thiab Irms tus nqi ntawm RF tam sim no los ntawm inductor, yuav tsum paub. Rau ntau qhov teeb meem ntau zaus suab nrov yuav raug lim, tag nrho AC lub zog dissipated los ntawm inductor yog sumof tag nrho Irms2 × ESR pab, qhov twg ESR sib txawv foreach pab los ntawm zaus.
Wideband RF chokes
Qhov kev ua tau zoo ntawm kev siv dav dav ntawm RF chokes yog qhov tshwm sim ntawm kev siv cov khoom tseem ceeb permeability xws li hmoov hlau lossis ferrite. Nrog RF signals taug kev los ntawm inductor, zaus-dependent thiab tam sim no-dependentcore poob ua rau cov cua sov ntxiv rau tag nrho cov khoom tsim los ntawm inductor. Ib qho yooj yim ESR ntsuas (feem ntau ua nyob rau tam sim no tsawg heev) yuav tsis ntes tau cov kev poob.Yog li ntawd txoj kev kwv yees saum toj no tsis muaj feem xyuam thiab tsis raug kwv yees qhov kub siab tshaj qhov yuav tshwm sim. Lub inductor yuav kub dua li qhov xav tau.Qhov zoo ib yam yog qhov tseeb rau txhua tus inductor uas muaj lub siab perme-muaj peev xwm (ferrite, hmoov hlau, sib xyaw) core. Nyob rau hauv cov ntaub ntawv ntawm high-perm core cov khoom, peb xav kom ua kub nce ntsuas ntawm lub inductor nyob rau hauv tag nrho cov mob ntawm zaus thiab tam sim no uas yuav ua rau koj daim ntawv thov los txiav txim qhov phem tshaj kub nce.