Cov ntawv luam tawm Circuit Board (PCB) thaiv kab ua lub luag haujlwm tseem ceeb hauv kev kub ceev Circuit Court, tab sis feem ntau nws yog ib qho ntawm cov kauj ruam kawg hauv cov txheej txheem tsim hluav taws xob. Muaj ntau yam teeb meem nrog kev kub ceev PCB thaiv, thiab ntau cov ntaub ntawv tau sau rau ntawm lub ncauj lus no. Kab lus no feem ntau tham txog kev xaim hluav taws xob ntawm kev kub ceev los ntawm kev pom zoo. Lub hom phiaj tseem ceeb yog los pab cov neeg siv tshiab them rau ntau yam teeb meem sib txawv uas yuav tsum tau xav txog thaum tsim kev kub ceev Circuit Court PCB layouts. Lwm lub hom phiaj yog muab cov ntaub ntawv tshuaj xyuas rau cov neeg siv khoom uas tsis tau kov PCB thaiv ib ntus. Vim qhov kev txwv tsis pub dhau, tsab xov xwm no tsis tuaj yeem tham txog txhua qhov teeb meem hauv kev nthuav dav, tab sis peb yuav tham txog cov ntsiab lus tseem ceeb uas muaj txiaj ntsig zoo tshaj plaws rau kev txhim kho kev ua haujlwm hauv Circuit Court, txo lub sijhawm tsim, thiab txuag lub sijhawm hloov kho.

Txawm hais tias lub ntsiab lus tseem ceeb ntawm no yog nyob rau hauv circuits ntsig txog kev ua haujlwm siab ceev amplifiers, cov teeb meem thiab cov kev sib tham ntawm no feem ntau siv tau rau kev xaim siv nyob rau hauv feem ntau lwm cov high-speed analog circuits. Thaum lub lag luam amplifier ua hauj lwm nyob rau hauv ib tug heev high zaus xov tooj cua zaus (RF) zaus band, qhov kev ua tau zoo ntawm lub Circuit Court feem ntau nyob ntawm lub PCB layout. Kev tsim hluav taws xob zoo tshaj plaws uas zoo li "daim duab" tuaj yeem tau txais kev ua haujlwm zoo tib yam yog tias lawv raug cuam tshuam los ntawm kev tsis saib xyuas thaum xaim. Kev txiav txim siab ua ntej thiab ua tib zoo saib xyuas cov ntsiab lus tseem ceeb thoob plaws hauv cov txheej txheem xaim yuav pab ua kom ntseeg tau tias qhov kev xav tau ntawm Circuit Court.

Schematic daim duab

Txawm hais tias ib qho zoo schematic tsis tuaj yeem lav qhov xaim zoo, kev xaim zoo pib nrog qhov zoo schematic. Ua tib zoo xav thaum kos duab schematic, thiab koj yuav tsum xav txog lub teeb liab ntws ntawm tag nrho cov circuit. Yog tias muaj cov teeb liab zoo li qub thiab ruaj khov ntws los ntawm sab laug mus rau sab xis hauv schematic, ces yuav tsum muaj tib lub teeb liab zoo ntws ntawm PCB. Muab cov ntaub ntawv muaj txiaj ntsig ntau li ntau tau ntawm schematic. Vim tias qee zaum cov kws tsim hluav taws xob tsim hluav taws xob tsis nyob ntawd, cov neeg siv khoom yuav thov kom peb pab daws qhov teeb meem hauv Circuit Court, cov neeg tsim khoom, cov kws tshaj lij thiab cov kws tshaj lij uas koom nrog txoj haujlwm no yuav ua tsaug ntau, nrog rau peb.

Ntxiv nrog rau cov ntaub ntawv qhia txog kev siv hluav taws xob, kev siv hluav taws xob, thiab kev ua yuam kev, cov ntaub ntawv dab tsi yuav tsum tau muab rau hauv schematic? Nov yog qee cov lus qhia kom tig schematics zoo tib yam rau hauv thawj chav kawm schematics. Ntxiv waveforms, txhua yam ntaub ntawv hais txog lub plhaub, ntev ntawm cov kab luam tawm, qhov chaw dawb paug; qhia tias cov khoom twg yuav tsum tau muab tso rau ntawm PCB; muab cov ntaub ntawv hloov kho, cov nqi ntawm cov khoom sib txuas, cov ntaub ntawv kub dissipation, tswj impedance cov kab luam tawm, cov lus pom, thiab cov lus piav qhia luv luv Action… (thiab lwm yam).
Txhob ntseeg leej twg

Yog tias koj tsis tsim cov kab hluav taws xob rau koj tus kheej, nco ntsoov tso sijhawm txaus los ua tib zoo xyuas tus neeg xaim tus tsim. Kev tiv thaiv me me yog tsim nyog ib puas npaug ntawm qhov kev kho ntawm lub sijhawm no. Tsis txhob cia siab tias tus neeg xa xov yuav nkag siab koj lub tswv yim. Koj lub tswv yim thiab kev taw qhia yog qhov tseem ceeb tshaj plaws nyob rau theem pib ntawm kev tsim cov txheej txheem. Cov ntaub ntawv ntau dua koj tuaj yeem muab tau, thiab qhov ntau koj cuam tshuam rau tag nrho cov txheej txheem xaim, qhov ua tau zoo ntawm PCB yuav zoo dua. Teem lub ntsiab lus ua tiav rau kev tsim hluav taws xob tsim hluav taws xob-xyuas ceev raws li daim ntawv tshaj tawm xov xwm koj xav tau. Txoj kev "kaw kaw" no tiv thaiv kev xaim los ntawm kev ua yuam kev, yog li txo qhov muaj peev xwm rov ua haujlwm dua.

Cov lus qhia uas yuav tsum tau muab rau tus kws tsim hluav taws xob muaj xws li: cov lus piav qhia luv luv ntawm kev ua haujlwm hauv Circuit Court, daim duab kos duab ntawm PCB qhia txog cov tswv yim thiab cov khoom tso tawm, cov ntaub ntawv PCB stacking (piv txwv li, lub rooj tsav tsheb tuab npaum li cas, muaj pes tsawg txheej. muaj, thiab cov ncauj lus kom ntxaws txog txhua lub teeb liab txheej thiab hauv av dav hlau-ua haujlwm Lub zog noj, hauv av hlau, analog teeb liab, digital teeb liab thiab RF teeb liab); uas cov cim qhia yuav tsum tau rau txhua txheej; xav tau kev tso kawm ntawm cov khoom tseem ceeb; qhov tseeb qhov chaw ntawm bypass Cheebtsam; cov kab ntawv twg yog qhov tseem ceeb; cov kab twg yuav tsum tau tswj cov kab impedance luam tawm; Cov kab twg yuav tsum tau ua kom haum qhov ntev; qhov loj ntawm cov khoom; uas cov kab luam tawm yuav tsum nyob deb (los yog ze rau) ib leeg; cov kab twg yuav tsum nyob deb (los yog ze rau) ib leeg; uas cov khoom yuav tsum nyob deb (los yog ze) rau ib leeg; cov khoom twg yuav tsum tau muab tso rau saum lub PCB, cov khoom twg tau muab tso rau hauv qab no. Tsis txhob yws tias muaj cov ntaub ntawv ntau dhau rau lwm tus - tsawg dhau? Puas yog ntau dhau lawm? Tsis txhob.

Ib qho kev kawm paub: Txog 10 xyoo dhau los, kuv tau tsim cov txheej txheem ntau txheej ntawm lub rooj tsavxwm-muaj cov khoom ntawm ob sab ntawm lub rooj tsavxwm. Siv ntau cov ntsia hlau los txhim kho lub rooj tsavxwm hauv lub plhaub kub-plated aluminium (vim tias muaj cov ntsuas ntsuas kev vibration nruj heev). Cov pins uas muab kev tsis ncaj ncees feedthrough dhau los ntawm lub rooj tsavxwm. Tus pin no txuas nrog PCB los ntawm cov xov hlau. Qhov no yog ib qho khoom siv nyuaj heev. Qee cov khoom ntawm lub rooj tsavxwm yog siv rau qhov kev xeem (SAT). Tab sis kuv tau hais meej meej qhov chaw ntawm cov khoom no. Koj puas tuaj yeem kwv yees qhov twg cov khoom no raug teeb tsa? Los ntawm txoj kev, nyob rau hauv lub board. Thaum cov khoom engineers thiab cov kws kho mob yuav tsum tau disassemble tag nrho cov cuab yeej thiab reassemble lawv tom qab ua tiav cov kev teeb tsa, lawv zoo li tsis zoo siab heev. Kuv tsis tau ua qhov yuam kev no dua txij thaum ntawd los.

Txoj hauj lwm

Ib yam li hauv PCB, qhov chaw yog txhua yam. Qhov twg yuav muab ib lub voj voog rau ntawm PCB, qhov twg rau nruab nws cov khoom siv hluav taws xob tshwj xeeb, thiab lwm cov kab hluav taws xob uas nyob ib sab yog dab tsi, txhua qhov tseem ceeb heev.

Feem ntau, txoj haujlwm ntawm kev tawm tswv yim, tso tawm, thiab lub zog hluav taws xob tau txiav txim siab ua ntej, tab sis lub voj voog ntawm lawv yuav tsum "ua si lawv tus kheej muaj tswv yim." Qhov no yog vim li cas kev xyuam xim rau cov ntaub ntawv xov tooj yuav ua rau muaj txiaj ntsig zoo. Pib nrog qhov chaw ntawm cov khoom tseem ceeb thiab xav txog qhov tshwj xeeb Circuit Court thiab tag nrho PCB. Kev qhia qhov chaw ntawm cov khoom tseem ceeb thiab cov teeb liab txoj hauv kev los ntawm qhov pib pab kom paub tseeb tias tus qauv tsim ua tau raws li cov hom phiaj ua haujlwm. Tau txais kev tsim qauv zoo thawj zaug tuaj yeem txo cov nqi thiab siab-thiab ua kom lub voj voog loj hlob sai.

Bypass lub zog

Bypassing lub hwj chim mov ntawm lub hwj chim ntawm lub amplifier thiaj li yuav txo tau suab nrov yog ib qho tseem ceeb nam nyob rau hauv lub PCB tsim txheej txheem-xws li high-ceev ua hauj lwm amplifiers los yog lwm yam high-ceev circuits. Muaj ob txoj hauv kev teeb tsa rau kev hla kev ua haujlwm siab ceev amplifiers.

Grounding lub hwj huam mov davhlau ya nyob twg: Txoj kev no yog qhov zoo tshaj plaws nyob rau hauv feem ntau, siv ntau yam parallel capacitors ncaj qha rau hauv pem teb lub hwj chim mov pin ntawm lub lag luam amplifier. Feem ntau hais lus, ob qho tib si capacitor yog qhov txaus-tab sis ntxiv cov kab hluav taws xob sib txuas yuav tau txais txiaj ntsig rau qee lub voj voog.

Kev sib txuas ntawm cov capacitors nrog qhov sib txawv ntawm qhov muaj peev xwm pab tau kom ntseeg tau tias tsuas yog qhov tsis tshua muaj hluav taws xob hloov pauv tam sim no (AC) impedance tuaj yeem pom ntawm lub hwj huam mov pin hla lub dav zaus band. Qhov no yog ib qho tseem ceeb tshwj xeeb tshaj yog nyob rau hauv attenuation zaus ntawm kev ua hauj lwm amplifier fais fab mov rejection ratio (PSR). Qhov no capacitor pab them nyiaj rau qhov txo qis PSR ntawm lub amplifier. Kev tuav txoj hauv kev qis impedance hauv ntau qhov ntau ntawm kaum-octave yuav pab xyuas kom meej tias cov suab nrov tsis zoo tuaj yeem nkag mus rau op amp. Daim duab 1 qhia qhov zoo ntawm kev siv ntau lub capacitors nyob rau hauv parallel. Ntawm qhov tsawg zaus, cov capacitors loj muab ib txoj hauv av uas tsis muaj impedance. Tab sis thaum lub zaus nce mus txog lawv tus kheej resonant zaus, lub capacitance ntawm lub capacitor yuav tsis muaj zog thiab maj mam tshwm inductive. Qhov no yog vim li cas nws yog ib qho tseem ceeb uas yuav tsum tau siv ntau lub capacitor: thaum cov lus teb zaus ntawm ib lub capacitor pib poob, cov lus teb zaus ntawm lwm lub capacitor pib ua haujlwm, yog li nws tuaj yeem tswj tau AC impedance tsawg heev nyob rau hauv ntau yam kaum-octave.

Pib ncaj qha nrog lub hwj huam mov pins ntawm op amp; lub capacitor nrog qhov tsawg tshaj plaws capacitance thiab lub cev me tshaj plaws yuav tsum tau muab tso rau ntawm tib sab ntawm PCB raws li op amp - thiab ze li sai tau rau lub amplifier. Lub davhlau ya nyob twg hauv av ntawm lub capacitor yuav tsum tau txuas ncaj qha rau hauv av dav hlau nrog tus pin luv tshaj plaws lossis cov ntawv luam tawm. Kev sib txuas hauv av saum toj no yuav tsum nyob ze li sai tau rau qhov chaw thau khoom ntawm lub tshuab hluav taws xob txhawm rau txhawm rau txo qhov cuam tshuam ntawm lub hwj chim davhlau ya nyob twg thiab hauv av davhlau ya nyob twg.

Cov txheej txheem no yuav tsum tau rov ua dua rau cov capacitors nrog tus nqi loj tshaj plaws tom ntej. Nws yog qhov zoo tshaj plaws los pib nrog qhov tsawg kawg nkaus capacitance tus nqi ntawm 0.01 µF thiab tso 2.2 µF (los yog loj dua) electrolytic capacitor nrog qis sib npaug series tsis kam (ESR) ze rau nws. Lub 0.01 µF capacitor nrog 0508 rooj plaub muaj tsawg heev series inductance thiab kev ua haujlwm zoo heev.

Fais fab mov rau lub hwj chim mov: Lwm txoj kev teeb tsa siv ib lossis ntau dua bypass capacitors txuas nrog thoob plaws lub zog zoo thiab tsis zoo ntawm lub tshuab hluav taws xob ua haujlwm. Txoj kev no feem ntau yog siv thaum nws nyuaj rau kev teeb tsa plaub lub capacitors hauv Circuit Court. Nws qhov tsis zoo yog tias cov ntaub ntawv loj ntawm lub capacitor tuaj yeem nce ntxiv vim tias qhov hluav taws xob hla lub capacitor yog ob npaug ntawm tus nqi hluav taws xob hauv ib txoj kev bypass. Kev nce qhov voltage yuav tsum tau nce qhov ntsuas hluav taws xob tawg ntawm lub cuab yeej, uas yog, ua kom lub tsev loj. Txawm li cas los xij, txoj kev no tuaj yeem txhim kho PSR thiab kev ua haujlwm tsis zoo.

Vim hais tias txhua lub voj voog thiab cov xaim sib txawv, qhov kev teeb tsa, tus lej thiab tus nqi capacitance ntawm cov capacitors yuav tsum tau txiav txim siab raws li qhov yuav tsum tau ua ntawm qhov tseeb Circuit Court.