PCB dhizaini yemusanganiswa chiratidzo chedunhu yakaoma kwazvo. Iyo dhizaini uye wiring yezvikamu uye kugadzirisa kwesimba rekupa uye pasi waya zvinokanganisa zvakananga kuita kwedunhu uye electromagnetic kuenderana kuita. Dhizaini yekuparadzanisa yepasi uye magetsi anounzwa mubepa rino anogona kukwidziridza kushanda kweakasanganiswa-signal maseketi.

Nzira yekudzikisa sei kupindira pakati pedhijitari uye analog masaini? Misimboti miviri yakakosha yekuenderana kwe electromagnetic (EMC) inofanirwa kunzwisiswa isati yagadzirwa: yekutanga musimboti kudzikisa nharaunda yeyazvino loop; Chechipiri musimboti nderekuti sisitimu inoshandisa ndege imwe chete yereferensi. Zvakapesana, kana sisitimu yacho iine ndege mbiri dzereferenzi, zvinokwanisika kugadzira dipole antenna (chinyorwa: radiation yediki dipole antenna inoenderana nehurefu hwemutsara, huwandu hwekuyerera ikozvino, uye frequency). Kana iyo chiratidzo ikasadzoka kuburikidza nediki diki chiuno, hombe denderedzwa antenna inogona kuumbwa. Dzivisa zvose mukugadzira kwako zvakanyanya sezvinobvira.

Izvo zvave zvataurwa kuti zviparadzanise ivhu redhijitari uye ivhu reanalogi pane yakasanganiswa-chiratidzo chedunhu bhodhi kuti uwane kuzviparadzanisa pakati pedhijitari pasi uye analogi pasi. Kunyangwe nzira iyi ichigoneka, ine matambudziko akawanda anogona kuitika, kunyanya mumahombe uye akaomarara masisitimu. Dambudziko rakanyanya kuoma ndere kuyambuka kupatsanurwa gap wiring, kana ukangoyambuka iyo partition gap wiring, electromagnetic radiation uye signal crosstalk inowedzera zvakanyanya. Dambudziko rinonyanya kuitika muPCB dhizaini idambudziko reEMI rinokonzerwa nemutsara wechiratidzo kuyambuka pasi kana magetsi.

Sezvinoratidzwa muMufananidzo 1, tinoshandisa nzira yekuparadzanisa iri pamusoro, uye mutsara wechiratidzo unotenderera pakati pevhu mbiri, ndeipi nzira yekudzoka yechiratidzo chemazuva ano? Ngatitii nyika mbiri dzakapatsanurwa dzakabatana pane imwe nguva (kazhinji inzvimbo imwe pane imwe nguva), panguva iyo nyika iripo inoumba chishwe chikuru. Iyo yakakwirira frequency ikozvino inoyerera kuburikidza nehombe loop inoburitsa radiation uye yakakwirira pasi inductance. Kana iyo yakaderera nhanho analog ikozvino inoyerera kuburikidza nehombe loop iri nyore kukanganiswa nekunze masaini. Chinhu chakaipisisa ndechokuti kana zvikamu zvabatanidzwa pamwe chete panzvimbo yemagetsi, guru guru remazuva ano rinoumbwa. Pamusoro pezvo, analogi uye ivhu redhijitari rakabatana netambo refu inoumba dipole antenna.

Kunzwisisa nzira uye maitiro ekudzokera kumashure kusvika pasi ndiyo kiyi yekugonesa yakasanganiswa-chiratidzo chedunhu dhizaini dhizaini. Mazhinji mainjiniya edhizaini anongofunga chete uko chiratidzo chazvino chinoyerera, tichiregeredza nzira chaiyo yezvino. Kana iyo yepasi pasi ichifanira kukamurwa uye ichifanira kufambiswa nepamukaha pakati pezvikamu, imwe poindi yekubatanidza inogona kuitwa pakati pevhu rakakamurwa kuita bhiriji rekubatanidza pakati pematanho maviri epasi uye wozofambiswa nepakati pebhiriji rekubatanidza. Nenzira iyi, yakananga ikozvino backflow nzira inogona kupihwa pazasi yega yega chiratidzo mutsara, zvichikonzera diki loop nzvimbo.

Optical yekuzviparadzanisa nevamwe kana ma transformer anogona zvakare kushandiswa kuona chiratidzo chinoyambuka chikamu chechikamu. Kune yekutanga, ndiyo chiratidzo chemaziso chinotenderera chikamu chechikamu. Panyaya ye transformer, isimba remagineti rinotenderedza gap rekuparadzanisa. Zviratidzo zvakasiyana zvinogonekawo: zviratidzo zvinoyerera kubva kune imwe mutsara uye kudzoka kubva kune imwe, iyo iyo inoshandiswa senzira dzekudzokera shure pasina chikonzero.

Kuti tiongorore kukanganiswa kwechiratidzo chedhijitari kune analog chiratidzo, isu tinofanira kutanga tanzwisisa maitiro eiyo yakakwira frequency ikozvino. High-frequency current inogara ichisarudza nzira ine yakaderera impedance (inductance) yakananga pazasi pechiratidzo, saka iyo yekudzoka ikozvino ichayerera kuburikidza neiri pedyo redunhu layer, zvisinei nekuti iyo iri padhuze ndiyo yemagetsi dhizaini kana pasi pasi.

Mukuita, zvinowanzosarurwa kushandisa yunifomu PCB kupatsanura kuita analog uye dijitari zvikamu. Analogi masaini anofambiswa munharaunda yeanalog yeese masheji ebhodhi, nepo masaini edhijitari achifambiswa munharaunda yedhijitari yedunhu. Muchiitiko ichi, chiratidzo chedhijitari chekudzoka ikozvino hachiyerere muvhu rechiratidzo cheanalog.

Kukanganisa kubva kumasaini edhijitari kuenda kumasaini eanalogi kunoitika chete kana masaini edhijitari achifambiswa pamusoro kana masaini eanalogi anofambiswa pamusoro pezvikamu zvedhijitari zvebhodhi redunhu. Dambudziko iri harisi nekuda kwekushaikwa kwezvikamu, chikonzero chaicho ndeye wiring isina kunaka yedhijitari masaini.

PCB dhizaini inoshandisa yakabatana, kuburikidza nedhijitari yedunhu uye analogi yedunhu kupatsanurwa uye yakakodzera chiratidzo wiring, kazhinji inogona kugadzirisa mamwe eakaomesesa dhizaini uye newaya matambudziko, asi zvakare haina rimwe dambudziko rinogona kukonzerwa nekukamurwa kwepasi. Muchiitiko ichi, kurongeka uye kupatsanurwa kwezvikamu zvinova zvakakosha pakusarudza kunaka kwekugadzirwa. Kana yakanyatsoiswa, iyo yedhijitari yepasi ikozvino ichaganhurwa kune yedhijitari chikamu chebhodhi uye haizokanganise chiratidzo cheanalog. Wiring yakadaro inofanira kunyatsotariswa uye kuongororwa kuti ive nechokwadi che 100% kutevedza mitemo ye wiring. Zvikasadaro, mutsara wechiratidzo usina kufanira uchaparadza zvachose bhodhi redunhu rakanaka.

Kana uchibatanidza analog nedhijitari pasi mapini eA/D anoshandura pamwechete, vazhinji vanoshandura A/D vagadziri vanokurudzira kubatanidza AGND neDGND pini kune imwechete yakaderera-impedance pasi uchishandisa mapfupi anotungamira (Cherekedza: Nekuti mazhinji maA/D anoshandura machipisi haabatanidze analog nedhijitari ivhu pamwe chete mukati, iyo analog nedhijitari ivhu rinofanirwa kubatanidzwa kuburikidza nekunze mapini), chero yekunze impedance yakabatana neDGND ichabatanidza ruzha rwedhijitari kudunhu reanalog mukati meIC kuburikidza neparasitic. capacitance. Kutevera kurudziro iyi, ese A/D converter AGND uye DGND pini dzinoda kubatanidzwa kune analog pasi, asi nzira iyi inomutsa mibvunzo yakadai sekuti kuguma kwepasi kwedhijitari chiratidzo decoupling capacitor kunofanirwa kubatanidzwa kune analog kana dhijitari pasi.

Kana iyo system iine imwe chete A/D converter, dambudziko riri pamusoro rinogona kugadziriswa nyore. Sezvinoratidzwa muMufananidzo 3, ivhu rakakamurwa uye zvikamu zveanalogi nedhijitari zvakabatanidzwa pasi peA/D converter. Kana iyi nzira ikagamuchirwa, zvinodikanwa kuve nechokwadi kuti hupamhi hwebhiriji pakati penzvimbo mbiri dzakaenzana nehupamhi hweIC, uye kuti hapana mutsara wechiratidzo unogona kuyambuka gap rekuparadzanisa.

Kana iyo system ine akawanda A/D anoshandura, semuenzaniso, gumi A/D anoshandura nzira yekubatanidza? Kana analogi uye ivhu redhijitari zvakabatana pasi pega yega A/D converter, A multipoint connection ichaguma, uye kuparadzaniswa pakati peanalog nedigital ground kuchave kusina zvazvinoreva. Kana ukasadaro, unotyora zvinodiwa nemugadziri.

Nzira yakanakisisa ndeyokutanga neyunifomu. Sezvinoratidzwa muMufananidzo 4, pasi rakakamurwa zvakafanana kuita analogi uye zvikamu zvedhijitari. Iyi dhizaini haizadzise chete zvinodiwa neIC vagadziri vemidziyo yepasi impedance yekubatanidza analog uye yedhijitari pasi pini, asi zvakare inodzivirira EMC matambudziko anokonzerwa ne loop antenna kana dipole antenna.

Kana iwe uine kusahadzika nezve yakabatana nzira yekusanganiswa-chiratidzo chePCB dhizaini, unogona kushandisa nzira yepasi layer yekuparadzanisa kuisa kunze uye nzira yese yedunhu bhodhi. Mukugadzira, kutarisisa kunofanirwa kubhadharwa kuita kuti bhodhi redunhu rive nyore kubatanidzwa pamwe chete nevanosvetuka kana 0 ohm resistors akapatsanurwa isingasviki 1/2 inch kure mukuedza kwakazotevera. Chenjerera kune zoning uye wiring kuti uone kuti hapana mitsara yedhijitari yedhijitari iri pamusoro pechikamu cheanalog pane ese akaturikidzana uye kuti hapana mitsara yeanalogi yechiratidzo iri pamusoro pechikamu chedhijitari. Uyezve, hapana mutsara wechiratidzo unofanirwa kuyambuka gap repasi kana kupatsanura mukaha pakati pezvitubu zvemagetsi. Kuti uedze mashandiro ebhodhi uye mashandiro eEMC, ongororazve mashandiro ebhodhi uye mashandiro eEMC nekubatanidza iwo maviri pasi pamwechete kuburikidza ne0 ohm resistor kana jumper. Tichienzanisa mhedzisiro yebvunzo, zvakaonekwa kuti mune dzinenge dzese nyaya, iyo yakabatana mhinduro yaive yepamusoro maererano nekushanda uye EMC kuita kana ichienzaniswa neyakapatsanurwa mhinduro.

Nzira yekugovanisa ivhu ichiri kushanda here?

Iyi nzira inogona kushandiswa mumamiriro matatu ezvinhu: mamwe maturusi ezvokurapa anoda yakaderera kwazvo kuvuza ikozvino pakati pemaseketi uye masisitimu akabatana nemurwere; Kubuda kweimwe maindasitiri process control michina inogona kunge yakabatana kune ruzha uye yakakwirira-simba electromechanical michina; Imwe nyaya ndeye apo iyo LAYOUT yePCB iri pasi pezvirambidzo zvakati.

Kune anowanzo kuparadzaniswa edhijitari uye analog magetsi emagetsi pane yakasanganiswa-chiratidzo PCB bhodhi iyo inogona uye inofanirwa kuve neyakapatsanurwa magetsi emagetsi kumeso. Zvisinei, mitsetse yezviratidzo iri padyo netambo yemagetsi haigoni kuyambuka mukaha pakati pemagetsi emagetsi, uye mitsetse yose yechiratidzo inoyambuka gap inofanira kunge iri panzvimbo yedunhu yakatarisana nenzvimbo huru. Mune zvimwe zviitiko, iyo analog magetsi emagetsi anogona kugadzirwa nePCB yekubatanidza kwete chiso chimwe chete kudzivirira simba kumeso kupatsanuka.

Chikamu dhizaini yeakasanganiswa chiratidzo PCB

Yakasanganiswa-chiratidzo PCB dhizaini inzira yakaoma, maitiro ekugadzira anofanirwa kutarisisa kune anotevera mapoinzi:

1. Kamura PCB muzvikamu zvakasiyana zveanalogi nedhijitari.

2. Yakakodzera chikamu marongerwo.

3. A/D converter inoiswa pamativi ese.

4. Usatsemura ivhu. Chikamu cheanalogi uye chikamu chedhijitari chebhodhi redunhu zvakaiswa zvakafanana.

5. Muzvikamu zvose zvebhodhi, chiratidzo chedhijitari chinogona kungofambiswa muchikamu chedhijitari chebhodhi.

6. Muzvikamu zvose zvebhodhi, zviratidzo zveanalogi zvinogona kungofambiswa muchikamu cheanalogi chebhodhi.

7. Analog uye dijitari simba kupatsanurwa.

8. Wiring haifanire kupfuudza mukaha pakati penzvimbo dzekutsemura magetsi.

9. Mitsetse yechiratidzo iyo inofanirwa kutambanudza mukaha pakati pemagetsi akapatsanurwa anofanira kunge ari pane iyo wiring layer yakatarisana nenzvimbo yakakura.

10. Ongorora nzira chaiyo uye nzira yekuyerera kwepasi ikozvino.

11. Shandisa mitemo yakarurama ye wiring.