Nzira yekuwana sei partition dhizaini yemusanganiswa-chiratidzo chePCB?

Abstract: Dhizaini yemusanganiswa-chiratidzo chedunhu PCB yakaoma zvikuru. Iyo dhizaini uye wiring yezvikamu uye kugadzirisa kwemagetsi uye waya yepasi zvinokanganisa zvakananga kuita kwedunhu uye electromagnetic kuenderana kuita. Iyo yekuparadzanisa dhizaini yepasi uye simba yakaunzwa muchinyorwa chino inogona kukwidziridza kuita kweakasanganiswa-signal maseketi.

ipcb

Maitiro ekudzikisa kupindirana pakati pedhijitari chiratidzo uye analog chiratidzo? Tisati tagadzira, isu tinofanirwa kunzwisisa maviri emisimboti emagetsi kuenderana (EMC): Yekutanga musimboti kudzikisa nharaunda yeiko loop; chechipiri musimboti nderekuti sisitimu inoshandisa nzvimbo imwe chete yereferensi. Zvakapesana, kana sisitimu yacho iine mareferenzi maviri ndege, zvinokwanisika kuumba dipole antenna (Cherechedza: saizi yemwaranzi yediki dipole antenna inoenzanirana nehurefu hwemutsara, huwandu hwekuyerera ikozvino uye frequency); uye kana chiratidzo chisingakwanisi kupfuura zvakanyanya sezvinobvira Kudzoka kwechishwe chidiki kunogona kuumba antenna hombe (Cherechedza: saizi yemwaranzi yediki loop antenna inoenzanirana nenzvimbo yechiuno, ikozvino inoyerera nemuchiuno, uye sikweya. of the frequency). Dzivisa mamiriro maviri aya zvakanyanya sezvinobvira mukugadzira.

Zvinokurudzirwa kupatsanura digitaalinen pasi uye analoginen ivhu pamusoro yakavhenganiswa-chiratidzo redunhu bhodhi, kuitira kuti kuzviparadzanisa pakati digitaalinen pasi uye analoginen pasi inogona kuwanikwa. Kunyangwe iyi nzira ichigoneka, kune akawanda angangove matambudziko, kunyanya muakaoma mahombe masisitimu. Dambudziko rinonyanya kukosha nderekuti harigone kufambiswa pane gap rekuparadzanisa. Kana gaka rekuparadzanisa rafambiswa, electromagnetic radiation uye chiratidzo crosstalk inowedzera zvakanyanya. Dambudziko rinonyanya kuitika muPCB dhizaini nderekuti mutsara wechiratidzo unoyambuka ivhu rakakamurwa kana magetsi uye unoburitsa matambudziko eEMI.

Maitiro ekuzadzisa dhizaini yekuparadzanisa yeyakasanganiswa-chiratidzo chePCB

Sezvinoratidzwa muMufananidzo 1, tinoshandisa nzira yekuparadzanisa yataurwa pamusoro apa, uye mutsara wechiratidzo unodarika mukaha pakati pezvikonzero zviviri. Ndeipi nzira yekudzoka yechiratidzo chazvino? Tichifunga kuti zvikonzero zviviri zvakakamurwa zvakabatanidzwa pamwe chete pane imwe nzvimbo (kazhinji kacho kubatanidzwa kwepoinzi pane imwe nzvimbo), munyaya iyi, ikozvino pasi ichaita loop yakakura. Iyo yakakwirira-frequency ikozvino inoyerera kuburikidza nehombe loop inoburitsa mwaranzi uye yakakwirira pasi inductance. Kana iyo yakaderera-yepamusoro analog ikozvino inoyerera kuburikidza nehombe loop, ikozvino inokanganiswa nyore nyore nekunze zviratidzo. Chinhu chakaipisisa ndechokuti kana zvikonzero zvakakamurwa zvabatanidzwa pamwe chete pamagetsi, guru guru remazuva ano richaumbwa. Pamusoro pezvo, iyo analogi pasi uye dhijitari pasi zvakabatanidzwa newaya refu kuita dipole antenna.

Kunzwisisa nzira uye nzira yezvino kudzoka pasi ndiyo kiyi yekugadzirisa yakasanganiswa-chiratidzo chedunhu bhodhi dhizaini. Mazhinji mainjiniya ekugadzira anongofunga chete kuti chiratidzo chazvino chinoyerera, uye kufuratira nzira chaiyo yezvino. Kana iyo yepasi pasi ichifanira kukamurwa, uye wiring inofanirwa kufambiswa kuburikidza nemukaha pakati pezvikamu, imwe-poindi yekubatanidza inogona kuitwa pakati pezvikonzero zvakakamurwa kuita bhiriji rekubatanidza pakati pezvikonzero zviviri, uyezve wiring kuburikidza nebhiriji rekubatanidza. . Nenzira iyi, nzira yakananga yekudzoka ikozvino inogona kugoverwa pasi pemutsara wega wega wechiratidzo, kuitira kuti iyo loop nzvimbo yakaumbwa idiki.

Iko kushandiswa kwemagetsi ekuzviparadzanisa nevamwe kana ma transformer anogona zvakare kuwana chiratidzo pane iyo segmentation gap. Kune yekutanga, ndiyo chiratidzo chemaziso chinoyambuka gap rekuparadzanisa; munyaya ye transformer, ndiyo magnetic field inoyambuka gap rekuparadzanisa. Imwe nzira inogoneka ndeye kushandisa masaini masaini: chiratidzo chinoyerera kubva kune mumwe mutsara uye chinodzoka kubva kune imwe chiratidzo mutsara. Muchiitiko ichi, ivhu haridiwi senzira yekudzoka.

Kuti tiongorore zvakadzama kupindira kwemasaini edhijitari kune masaini eanalog, isu tinofanira kutanga tanzwisisa maitiro epamusoro-frequency currents. Kune yakakwirira-frequency currents, gara uchisarudza nzira ine zvishoma impedance (yakaderera inductance) uye yakananga pazasi pechiratidzo, saka iyo yekudzoka ikozvino inoyerera kuburikidza neiri padyo redunhu layer, zvisinei nekuti iyo iri padhuze ndiyo dhizaini yesimba kana pasi pasi. .

Mubasa chairo, rinowanzoda kushandisa ivhu rakabatana, uye kupatsanura PCB kuita chikamu cheanalogi uye chikamu chedhijitari. Chiratidzo cheanalog chinofambiswa munzvimbo yeanalog yezvikamu zvese zvebhodhi redunhu, uye chiratidzo chedhijitari chinofambiswa munzvimbo yedhijitari yedunhu. Muchiitiko ichi, chiratidzo chedhijitari chekudzoka ikozvino hachizoyerere muiyo analog chiratidzo pasi.

Chete kana chiratidzo chedhijitari chaiswa waya pane chikamu cheanalog chebhodhi redunhu kana chiratidzo cheanarogi chine waya pane chikamu chedhijitari chebhodhi redunhu, kupindira kwechiratidzo chedhijitari kuchiratidzo cheanalogi kuchaonekwa. Rudzi urwu rwedambudziko haruitike nekuti hapana ivhu rakakamurwa, chikonzero chaicho ndeye isina kunaka wiring yedhijitari chiratidzo.

PCB dhizaini inotora ivhu rakabatana, kuburikidza nedhijitari redhijitari uye analogi dunhu kupatsanurwa uye yakakodzera chiratidzo wiring, kazhinji inogona kugadzirisa mamwe magadzirirwo akaomarara uye matambudziko ewaya, uye panguva imwe chete, hazvizokonzeresa mamwe matambudziko anokonzerwa nekupatsanurwa kwevhu. Muchiitiko ichi, marongerwo uye kupatsanurwa kwezvikamu zvinova kiyi yekuona zvakanakira uye zvakaipira zvekugadzira. Kana iyo marongerwo inonzwisisika, iyo yedhijitari yepasi ikozvino ichave yakaganhurirwa kune yedhijitari chikamu chedunhu bhodhi uye haizokanganisa chiratidzo cheanalogi. Wiring dzakadaro dzinofanirwa kunyatsoongororwa uye kuongororwa kuti ive nechokwadi chekuti mitemo yewaya inoteererwa ne100%. Zvikasadaro, kufambiswa kwakashata kwemutsara wechiratidzo kuchaparadza zvachose imwe bhodhi yakanaka kwazvo.

Kana uchibatanidza ivhu reanalogi uye mapini epasi edhijitari yeA/D inoshandura pamwechete, vazhinji vagadziri veA/D vanoshandura vangakurudzira: Batanidza mapini eAGND neDGND kune imwechete yakaderera impedance pasi kuburikidza neapfupi lead. (Cherechedza: Nemhaka yokuti machipisi akawanda eA/D anoshandura haasanganisi pasi analogi uye pasi yedhijitari pamwe chete, iyo analogi uye pasi yedhijitari inofanira kubatanidzwa kuburikidza nekunze kwepini.) Chero ipi zvayo yekunze impedance yakabatana neDGND ichapfuura parasitic capacitance. Ruzha rwakawanda rwedhijitari rwakabatanidzwa kune analog maseketi mukati meIC. Zvinoenderana nekurudziro iyi, iwe unofanirwa kubatanidza iyo AGND uye DGND mapini eiyo A / D inoshandura kune iyo analog pasi, asi nzira iyi ichakonzera matambudziko akadai sekuti iyo yepasi terminal yedhijitari chiratidzo decoupling capacitor inofanira kubatanidzwa kune analog pasi. kana nzvimbo yedhijitari.

Maitiro ekuzadzisa dhizaini yekuparadzanisa yeyakasanganiswa-chiratidzo chePCB

Kana iyo system ine imwe chete A / D inoshandura, matambudziko ari pamusoro anogona kugadziriswa nyore. Sezvinoratidzwa muMufananidzo 3, patsanura pasi, uye batanidza pasi reanalogi uye pasi redhijitari pamwe chete pasi peA/D converter. Paunenge uchitora nzira iyi, zvinodikanwa kuve nechokwadi kuti hupamhi hwebhiriji rekubatanidza pakati pezvikonzero zviviri zvakaenzana nehupamhi hweIC, uye chero mutsara wechiratidzo haugone kuyambuka gap rekuparadzanisa.

Kana paine akawanda A/D anoshandura muhurongwa, semuenzaniso, nzira yekubatanidza 10 A/D converters? Kana iyo analog pasi uye ivhu redhijitari zvakabatana pamwe chete pasi pega yega A / D inoshandura, multi-point yekubatanidza inogadzirwa, uye kuparadzaniswa pakati peiyo analogi pasi uye yedhijitari ivhu hakuna zvazvinoreva. Kana iwe usingabatanidzi nenzira iyi, inopesana nezvinodiwa nemugadziri.