PCB tsim high-speed analog input teeb liab routing txoj kev

Qhov dav ntawm txoj kab dav, qhov muaj zog tiv thaiv kev cuam tshuam thiab qhov zoo ntawm cov teeb liab zoo (kev cuam tshuam ntawm daim tawv nqaij). Tab sis tib lub sijhawm, qhov yuav tsum tau muaj ntawm 50Ω yam ntxwv impedance yuav tsum tau lav. Ib txwm FR4 pawg thawj coj saib, kab dav dav 6MIL impedance yog 50Ω. Qhov no pom tseeb tsis tuaj yeem ua tau raws li cov teeb liab zoo uas yuav tsum tau muaj ntawm high-speed analog input, yog li peb feem ntau siv hollowing GND02 thiab cia nws xa mus rau ART03 txheej. Nyob rau hauv txoj kev no, lub teeb liab sib txawv tuaj yeem suav tias yog 12/10, thiab ib kab tuaj yeem suav tau li 18MIL. (Nco ntsoov tias txoj kab dav dav tshaj 18MIL thiab tom qab ntawd nthuav dav tsis muaj qab hau)

PCB tsim high-speed analog input teeb liab routing txoj kev thiab cov cai

CLINE tseem ceeb hauv ntsuab hauv daim duab yog hais txog ib kab thiab qhov sib txawv high-speed analog input ntawm ART03 txheej. Thaum ua li ntawd, qee cov ntsiab lus yuav tsum tau hais txog:

(1) Lub simulation ib feem ntawm TOP txheej yuav tsum tau ntim, raws li qhia hauv daim duab saum toj no. Nws yuav tsum tau muab sau tseg tias qhov kev ncua deb ntawm av tooj liab mus rau analog input CLINE yuav tsum yog 3W, uas yog, AIRGAP los ntawm ntug ntawm cov tooj liab mus rau CLINE yog ob zaug ntawm kab dav. Raws li ib co electromagnetic theoretical xam thiab simulations, lub magnetic teb thiab hluav taws xob teb ntawm lub teeb liab kab ntawm lub PCB yog mas faib nyob rau hauv ntau yam ntawm 3W. (Lub suab cuam tshuam los ntawm ib puag ncig cov cim qhia tsawg dua lossis sib npaug li 1%).

(2) GND tooj liab ntawm cov txheej zoo ntawm thaj chaw analog kuj yuav tsum tau muab cais tawm ntawm thaj chaw digital, uas yog, txhua txheej yog cais.

(3) Rau qhov hollowing ntawm GND02, peb feem ntau hollow tawm tag nrho cov cheeb tsam no, yog li kev khiav hauj lwm kuj yooj yim thiab tsis muaj teeb meem. Tab sis xav txog cov ntsiab lus lossis txhawm rau ua kom zoo dua, peb tuaj yeem tsuas yog hollow tawm qhov sib txuas ntawm cov khoom siv sib txuas, tau kawg, tib yam li TOP txheej, 3W cheeb tsam. Qhov no tuaj yeem lav qhov teeb meem zoo thiab qhov flatness ntawm lub rooj tsavxwm. Qhov kev tshwm sim yog raws li nram no:

PCB tsim high-speed analog input teeb liab routing txoj kev thiab cov cai

Nyob rau hauv txoj kev no, txoj kev rov qab los ntawm high-speed analog input teeb liab tuaj yeem rov qab sai sai ntawm GND02 txheej. Ntawd yog, txoj kev simulated hauv av rov qab ua luv dua.

(4) Tsis tu ncua xuas nrig ntaus ntau tus GND vias nyob ib ncig ntawm lub high-speed analog teeb liab kom cov analog teeb liab ntws rov qab sai. Nws kuj tuaj yeem nqus suab nrov.

PCB tsim high-speed analog input teeb liab routing txoj cai

Txoj Cai 1: High-speed PCB teeb liab routing shielding txoj cai Nyob rau hauv high-ceev PCB tsim, routing ntawm tseem ceeb high-ceev teeb liab kab xws li moos yuav tsum tau shielded. Yog tias tsis muaj ntaub thaiv npog lossis tsuas yog ib feem ntawm nws, nws yuav ua rau EMI to. Nws raug pom zoo tias cov hlau thaiv npog yuav tsum tau cog nrog ib lub qhov rau 1000 mil.

PCB tsim high-speed analog input teeb liab routing txoj kev thiab cov cai

Txoj Cai 2: High-speed signal routing kaw-voj txoj cai

Vim qhov nce ceev ntawm PCB cov laug cam, ntau tus PCB LAYOUT engineers muaj qhov ua yuam kev hauv cov txheej txheem ntawm kev sib txuas, uas yog, cov teeb liab ceev ceev xws li moos teeb liab, uas tsim cov voj voog kaw thaum routing multi-layer PCBs. Raws li qhov tshwm sim ntawm lub voj kaw, lub voj kav hlau txais xov yuav raug tsim, uas yuav ua rau kom muaj zog ntawm EMI.

PCB tsim high-speed analog input teeb liab routing txoj kev thiab cov cai

Txoj Cai 3: High-speed signal routing qhib voj kev cai

Txoj Cai 2 hais tias lub voj kaw ntawm cov teeb liab ceev yuav ua rau EMI hluav taws xob, tab sis lub voj qhib yuav ua rau EMI hluav taws xob.

High-speed signal networks xws li moos teeb liab, ib zaug ib qho kev qhib-voj tshwm sim thaum lub multilayer PCB raug xa mus, ib lub kav hlau txais xov kab yuav raug tsim, uas ua rau EMI hluav taws xob ntau dua.

PCB tsim high-speed analog input teeb liab routing txoj kev thiab cov cai

Txoj Cai 4: Cov yam ntxwv impedance txuas ntxiv txoj cai ntawm kev kub ceev teeb liab

Rau cov teeb liab ceev ceev, tus yam ntxwv impedance yuav tsum txuas ntxiv thaum hloov ntawm cov khaubncaws sab nraud povtseg, txwv tsis pub nws yuav nce EMI hluav taws xob. Hauv lwm lo lus, qhov dav ntawm cov xaim ntawm tib txheej yuav tsum tau txuas mus ntxiv, thiab qhov impedance ntawm cov xaim ntawm cov txheej txheem sib txawv yuav tsum tau txuas mus ntxiv.

PCB tsim high-speed analog input teeb liab routing txoj kev thiab cov cai

Txoj Cai 5: Cov kev taw qhia kev xaim hluav taws xob rau kev tsim PCB siab ceev

Kev xaim ntawm ob txheej uas nyob ib sab yuav tsum ua raws li txoj cai ntawm txoj kab ntsug, txwv tsis pub nws yuav ua rau crosstalk ntawm cov kab thiab nce EMI hluav taws xob.

Nyob rau hauv luv luv, cov kab hlau txuas uas nyob ib sab ua raws li kab rov tav thiab ntsug thaiv cov lus qhia, thiab cov kab ntsug tuaj yeem cuam tshuam cov crosstalk ntawm cov kab.

PCB tsim high-speed analog input teeb liab routing txoj kev thiab cov cai

Txoj Cai 6: Topological qauv cai hauv kev tsim PCB high-speed

Nyob rau hauv high-speed PCB tsim, kev tswj cov yam ntxwv impedance ntawm lub Circuit Court board thiab tsim ntawm lub topological qauv nyob rau hauv multi-load tej yam kev mob ncaj qha txiav txim qhov ua tau zoo los yog tsis ua hauj lwm ntawm cov khoom.

Daim duab qhia txog daisy saw topology, uas feem ntau tau txais txiaj ntsig thaum siv ob peb Mhz. Nws raug nquahu kom siv lub hnub qub zoo li tus qauv symmetrical nyob rau tom qab kawg hauv kev kub ceev PCB tsim.

PCB tsim high-speed analog input teeb liab routing txoj kev thiab cov cai

Txoj Cai 7: Resonance txoj cai ntawm kab ntev

Xyuas seb qhov ntev ntawm cov teeb liab kab thiab qhov zaus ntawm lub teeb liab ua rau resonance, uas yog, thaum qhov ntev ntawm cov xaim yog qhov sib npaug ntawm cov teeb liab wavelength 1/4, cov xov hlau yuav resonate, thiab cov resonance yuav radiate electromagnetic tsis. thiab ua rau muaj kev cuam tshuam.