Hunhu hushanu hwakakosha uye PCB dhizaini nyaya dzekufunga muEMC ongororo

Zvinonzi kune marudzi maviri chete emainjiniya emagetsi munyika: avo vakawana kukanganiswa kwemagetsi uye avo vasina.Nekuwedzera kwePCB chiratidzo frequency, EMC dhizaini idambudziko ratinofanira kufunga

1. Zvinhu zvishanu zvakakosha zvekufunga nezvazvo panguva yekuongorora EMC

Kutarisana nedhizaini, pane zvishanu zvakakosha hunhu hwekufunga kana uchiitisa EMC ongororo yechigadzirwa uye dhizaini:

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1).Saizi yekiyi mudziyo:

Hunhu hwemuviri hwechigadzirwa chinoburitsa chinoburitsa mwaranzi.Iyo redhiyo frequency (RF) ikozvino ichagadzira iyo electromagnetic munda, iyo inodonha kuburikidza neimba uye kunze kweimba.Iyo tambo kureba paPCB sezvo nzira yekufambisa ine yakananga kukanganisa paRF ikozvino.

2).Impedance kuenzanisa

Source uye inogamuchira impedances, uye kutapurirana impedances pakati pavo.

3).Temporal maitiro ezviratidzo zvekupindira

Dambudziko nderokuenderera mberi (periodic sign) chiitiko, kana kuti ingori chaiyo mashandiro kutenderera (semuenzaniso chiitiko chimwe chete chinogona kunge chiri keystroke kana simba-pakukanganisa, periodic disk drive oparesheni, kana network kuputika)

4).Simba rechiratidzo chekupindira

Isimba rakadii mwero wesimba rekwakabva, uye kuti ingani inokwanisa kuburitsa kukanganisa kunokuvadza

5).Frequency maitiro ezviratidzo zvekuvhiringidza

Uchishandisa spectrum analyzer kuona waveform, tarisa panoitika dambudziko mu spectrum, zviri nyore kuwana dambudziko.

Uye zvakare, mamwe akaderera frequency edunhu dhizaini maitiro anoda kutariswa.Semuyenzaniso, iyo yakajairwa single-point grounding yakanyatsokodzera kune yakaderera-frequency application, asi haina kukodzera masaini eRF uko kune mamwe matambudziko eEMI.

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Zvinotendwa kuti mamwe mainjiniya anozoshandisa imwe poindi yekudzika kune ese magadzirirwo echigadzirwa pasina kuziva kuti kushandiswa kweiyi nzira yekumisa kunogona kugadzira mamwe kana mamwe akaomarara EMC matambudziko.

Tinofanirawo kuterera kune ikozvino kuyerera muzvikamu zvedunhu.Kubva paruzivo rwedunhu, tinoziva kuti ikozvino inoyerera kubva kune yakakwira voltage kusvika kune yakaderera voltage, uye ikozvino nguva dzose inoyerera kuburikidza neimwe kana kupfuura nzira muvhavha-loop circuit, saka kune mutemo unokosha zvikuru: gadzira zvishoma zvishoma.

Kune iwo madhairekitori panoyerwa kupindira ikozvino, iyo PCB wiring inogadziridzwa kuitira kuti isakanganise mutoro kana dunhu rinonzwa.Zvishandiso zvinoda yakakwira impedance nzira kubva kune magetsi kuenda kumutoro zvinofanirwa kufunga nezvese nzira dzinogoneka iyo yekudzoka ikozvino inogona kuyerera.

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Isu tinofanirawo kuterera PCB wiring.Iyo impedance yewaya kana nzira ine kuramba R uye inductive reactance.Pama frequency akakwira, pane impedance asi hapana capacitive reactance.Kana iyo frequency yewaya iri pamusoro pe100kHz, waya kana waya inova inductor.Waya kana waya dzinoshanda pamusoro pekuteerera dzinogona kuita RF antennas.

Mukutsanangurwa kweEMC, waya kana waya hazvibvumidzwe kushanda pazasi λ/20 yeimwe frequency (iyo antenna yakagadzirirwa kuve λ/4 kana λ/2 yeimwe frequency).Kana isina kugadzirwa nenzira iyoyo, wiring inova antenna inoshanda zvakanyanya, ichiita kuti gare gare debugging itonyanya kuoma.

 

2.PCB chimiro

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Kutanga: Funga nezvehukuru hwePCB.Kana ukuru hwePCB hukuru, simba rinopesana nekupindira kwegadziriro inoderera uye mari inowedzera nekuwedzera kwetambo, nepo ukuru huri huduku, izvo zvinokonzera nyore nyore dambudziko rekupisa kupisa uye kupindirana.

Chechipiri: sarudza nzvimbo yezvikamu zvakakosha (zvakadai sezvinhu zvewachi) (wachi wiring yakanakisisa isina kuiswa pasi pasi uye usafamba-famba mitsetse yakakosha yechiratidzo, kudzivisa kupindira).

Chechitatu: zvinoenderana nebasa redunhu, iyo yakazara marongero ePCB.Muchigadziro chechikamu, zvikamu zvakabatana zvinofanira kunge zviri pedyo sezvinobvira, kuitira kuti uwane zviri nani zvinopesana nekupindira.