Jumper capacitors kana decoupling capacitors inogona kugadzirisa mamwe matambudziko, asi iyo impedance yese ye capacitors, vias, pads, uye wiring inofanirwa kutariswa.

Ichi chinyorwa chichasuma EMC's PCB dhizaini tekinoroji kubva pazvinhu zvitatu: PCB yekuisa zano, hunyanzvi hwekugadzirisa uye mitemo yewaya.

PCB layering strategy

Ukobvu, kuburikidza nemaitiro uye huwandu hwezvikamu mudhizaini yedhizaini haisi kiyi yekugadzirisa dambudziko.Yakanaka yakaturikidzana yakaturikidzana ndeyekuona iyo bypass uye decoupling yebhazi remagetsi uye kuderedza mhepo inotenderera pane yemagetsi layer kana pasi pasi.Kiyi yekudzivirira iyo electromagnetic munda wechiratidzo uye magetsi ekupa.

Kubva pakuona kwechiratidzo chechiratidzo, nzira yakanaka yekuisa inofanira kunge iri yekuisa zviratidzo zvese zvechiratidzo pane imwe kana kuti akati wandei, uye aya akaturikidzana ari padivi pesimba resimba kana pasi pasi.Nokuda kwekupa magetsi, nzira yakanaka yekuisa inofanira kunge iri iyo tambo yemagetsi iri pedyo nechepasi pasi, uye chinhambwe pakati pesimba remagetsi uye pasi pasi idiki sezvinobvira.Izvi ndizvo zvatiri kutaura nezve "layer" strategy.Pazasi isu tichanyatso taura nezve yakanaka PCB yekuisa zano.

1. Iyo ndege yekufungidzira yetambo ye wiring inofanira kunge iri munharaunda ye reflow plane layer.Kana iyo wiring layer isiri munzvimbo yekufungidzira yereflow plane layer, pachava nemitsara yechiratidzo kunze kwenzvimbo yekufungidzira panguva ye wiring, izvo zvinokonzeresa "edge radiation" matambudziko, uye zvakare ichawedzera nzvimbo yechiratidzo loop, zvichikonzera yakawedzera differential mode radiation .

2. Edza kudzivisa kumisikidza tambo dze wiring dziri pedyo.Nekuti masaini anoteedzana anoteedzera pane ari padhuze wiring akaturikidzana anogona kukonzera chiratidzo crosstalk, kana ari padhuze wiring akaturikidzana asingagoni kudziviswa, nzvimbo yepakati pakati pematanho maviri ewaya inofanira kuwedzerwa zvakafanira, uye nzvimbo yepakati pakati peiyo wiring layer uye chiratidzo chechiratidzo chayo inofanira kuderedzwa.

3. Matunhu endege ari pedyo anofanirwa kudzivirira kupindirana kwendege dzadzo.Nekuti kana mafungidziro apindirana, iyo coupling capacitance pakati pematanho inokonzeresa ruzha pakati pezvikamu kuti zvibatane.

Multilayer board design

Kana wachi frequency ichipfuura 5MHz, kana chiratidzo chekusimuka nguva isingasviki 5ns, kuitira kuti udzore nzvimbo yechiratidzo loop zvakanaka, dhizaini yebhodhi-yakawanda inowanzodiwa.Aya misimboti anotevera anofanirwa kutariswa kana uchigadzira multilayer mapuranga:

1. Iyo kiyi wiring layer (iyo layer iyo wachi mutsara, bhazi, interface chiratidzo mutsara, redhiyo frequency mutsara, reset chiratidzo mutsara, chip sarudza chiratidzo mutsara uye akasiyana mitsara yechiratidzo chekudzora iripo) inofanira kunge iri padhuze nendege yepasi, zvichida. pakati pendege mbiri dzepasi, Sezvinoratidzwa mumufananidzo 1.

Mitsetse yezviratidzo zvemakiyi kazhinji ine mwaranzi yakasimba kana kuti mitsetse yechiratidzo yakanyanyisa.Wiring padyo nendege yepasi inogona kudzikisa chiratidzo loop nzvimbo, kuderedza kusimba kwayo kwemwaranzi kana kuvandudza anti-kupindira kugona.

2. Ndege yemagetsi inofanira kudzoserwa maererano nendege yayo yepasi (inokurudzirwa kukosha 5H～20H).Kudzokororwa kwendege yemagetsi zvine chekuita nendege yayo yekudzokera pasi kunogona kunyatso kudzvanya dambudziko re "edge radiation", sezvakaratidzwa mumufananidzo 2.

Mukuwedzera, iyo huru yekushanda simba ndege yebhodhi (iyo inonyanya kushandiswa simba ndege) inofanira kunge iri pedyo nendege yayo yepasi kuti ibudirire kuderedza loop nzvimbo yemagetsi ikozvino, sezvinoratidzwa mumufananidzo 3.

3. Kana pasina mutsara wechiratidzo ≥50MHz paTOP uye BOTTOM layer yebhodhi.Kana zvakadaro, zviri nani kufamba chiratidzo chepamusoro-soro pakati pezvikamu zviviri zvendege kudzvanyirira mwaranzi wayo kunzvimbo.

Single-layer board uye kaviri-layer board dhizaini

Nokuda kwekugadzirwa kwemabhodhi e-single-layer board uye maviri-layer board, kugadzirwa kwemitsara yezviratidzo zvakakosha uye mitsara yemagetsi inofanira kubhadharwa.Panofanira kuva newaya yepasi padivi uye inofambirana netambo yemagetsi kudzikisa nzvimbo yemagetsi ikozvino loop.

"Guide Ground Line" inofanira kuiswa kumativi ose emutsara wechiratidzo chekiyi yebhodhi imwe chete, sezvinoratidzwa muMufananidzo 4. Mutsara wechiratidzo chepamusoro webhodhi-layer board inofanira kuva nenzvimbo yakakura yepasi pane ndege yekufungidzira. , kana nzira imwechete sebhodhi-layer board, dhizaini "Guide Ground Line", sezvakaratidzwa muMufananidzo 5. I "guard ground wire" kumativi ose emutsara wechiratidzo chekiyi inogona kuderedza nzvimbo yechiratidzo chechiratidzo kune rumwe rutivi, uye zvakare kudzivirira crosstalk pakati pechiratidzo mutsara uye mamwe masaini mitsara.

Unyanzvi hwekugadzira PCB

Paunenge uchigadzira hurongwa hwePCB, unofanirwa kunyatsocherechedza nheyo yekugadzira yekuisa mumutsara wakarurama pamwe chete nechiratidzo chekuyerera kwechiratidzo, uye edza kudzivisa kutenderera mberi nekudzoka, sezvinoratidzwa mumufananidzo 6. Izvi zvinogona kudzivisa kubatanidza zviratidzo zvakananga uye kukanganisa unhu hwechiratidzo. .

Mukuwedzera, kuitira kudzivirira kupindirana uye kubatanidza pakati pemaseketi uye zvikamu zvemagetsi, kuiswa kwemaseketi uye kurongeka kwezvikamu kunofanirwa kutevedzera zvinotevera:

1. Kana "ivhu rakachena" rakagadzirwa pabhodhi, iyo yekusefa uye yekuzviparadzanisa zvikamu inofanira kuiswa pane yekuzviparadzanisa pakati pe "ivhu rakachena" uye ivhu rekushanda.Izvi zvinogona kudzivirira kusefa kana kuzviparadzanisa zvishandiso kubva pakubatana kune mumwe nemumwe kuburikidza neiyo planar layer, iyo inonetesa mhedzisiro.Mukuwedzera, pa "ivhu rakachena", kunze kwekusefa nekudzivirira zvishandiso, hapana mimwe michina inogona kuiswa.

2. Kana masekete akawanda emodule akaiswa paPCB imwechete, maseketi edhijitari uye analogi maseketi, epamusoro-speed uye yakaderera-speed maseketi anofanirwa kuiswa akaparadzana kuti arege kupindirana pakati pemaseketi edhijitari, maseketi eanalogi, maseketi akakwira-speed, uye akaderera. -speed circuits.Mukuwedzera, kana matunhu akakwirira, epakati, uye akadzika-speed aripo pabhodhi redunhu panguva imwe chete, kuitira kuti udzivise ruzha rwepamusoro-frequency redunhu kubva pakubuda kunze kuburikidza nekubatana, nheyo yegadziriro muMufananidzo 7 inofanira kuva.

3. Iyo sefa yedunhu remagetsi ekupinza chiteshi chebhodhi redunhu rinofanirwa kuiswa padyo neiyo interface kuti irege kubatanidzwazve kweiyo sefa yedunhu.

4. Iyo yekusefa, kudzivirira uye yekuzviparadzanisa zvikamu zveiyo interface yedunhu inoiswa padyo neiyo interface, sezvakaratidzwa muMufananidzo 9, iyo inogona kubudirira kubudirira mhedzisiro yekudzivirira, kusefa uye kuparadzaniswa.Kana paine zvese sefa uye seti yekudzivirira pane iyo interface, musimboti wekutanga kudzivirira uyezve kusefa kunofanirwa kuve .Nekuti dunhu redziviriro rinoshandiswa kune ekunze overvoltage uye overcurrent kudzvinyirira, kana dunhu redziviriro rakaiswa mushure mesefa redunhu, iyo sefa yedunhu ichakuvadzwa nekupfuura uye overcurrent.

Uye zvakare, sezvo iyo yekupinza uye yekubuda mitsara yedunhu inonetesa kusefa, kuzviparadzanisa kana kudzivirira maitiro kana akabatanidzwa pamwe chete, ive nechokwadi chekuti mitsara yekupinza uye yekubuda yemusefa wedunhu (sefa), yekuzviparadzanisa uye yekudzivirira yedunhu haiite. vakaroorana pamwe chete panguva yekugadzirisa.

5. Sensitive circuits kana zvikamu (zvakadai sereset circuits, nezvimwewo) zvinofanira kunge zviri zvishoma 1000 mils kubva kumucheto wega webhodhi, kunyanya kumucheto kwebhodhi interface.


6. Simba rekuchengetedza uye high-frequency filter capacitors inofanira kuiswa pedyo ne unit circuits kana zvishandiso zvine shanduko huru yemazuva ano (yakadai sekuisa uye kubuda kwemagetsi emagetsi emagetsi, mafeni uye relays) kuderedza loop nzvimbo yemazuva ano makuru. zvishwe.

7. Zvikamu zvesefa zvinofanira kuiswa padivi nedivi kuti zvidzivise dunhu rakacheneswa kuti rirege kukanganiswa zvakare.

8. Chengetedza midziyo yakasimba yemwaranzi yakadai sekristaro, crystal oscillators, relays, kushandura magetsi emagetsi, nezvimwewo kure nebhodhi interface yekubatanidza zvishoma ne1000 mils.Nenzira iyi, kupindira kunogona kuvhenekerwa zvakananga kunze kana ikozvino inogona kubatanidzwa kune inobuda tambo kuti ivheneke kune kunze.

REALTER: Yakadhindwa Circuit Board, PCB Dhizaini, PCB Gungano