Amathuluzi wendabuko wokulungisa amaphutha we PCB kufaka phakathi: i-oscilloscope yesizinda sesikhathi, i-TDR (i-time domain reflectometry) i-oscilloscope, i-logic analyzer, kanye ne-frequency domain spectrum analyzer neminye imishini, kepha lezi zindlela azikwazi ukunikeza ukubonakaliswa kwemininingwane ephelele yedatha yebhodi le-PCB. Leli phepha lethula indlela yokuthola imininingwane ephelele ye-electromagnetic ye-PCB enohlelo lwe-EMSCAN, iphinde ichaze ukuthi lolu lwazi lusetshenziswa kanjani ukusiza ukuklama nokulungisa iphutha.

I-EMSCAN inikeza imisebenzi yokuskena ye-spectrum neyesikhala. Imiphumela yokuskena kwe-spectrum ingasinikeza umbono ojwayelekile wobubanzi obukhiqizwe yi-EUT: zingaki izingxenye zemvamisa ezikhona, futhi yini ubukhulu obulinganiselwe bengxenye ngayinye yemvamisa. Umphumela wokuskena kwendawo ibalazwe lesimo sendawo esinombala omele ukuphakama kwephoyinti lokuvama. Siyabona ukusatshalaliswa kwenkambu enamandla kagesi wephoyinti elithile elenziwe yi-PCB ngesikhathi sangempela.

“Umthombo wokuphazamiseka” ungatholakala futhi ngokusebenzisa i-spectrum analyzer kanye ne-probe eyodwa eseduze kwenkundla. Lapha sebenzisa indlela “yomlilo” ukwenza isingathekiso, ungaqhathanisa ukuhlolwa kwensimu ekude (ukuhlolwa okujwayelekile kwe-EMC) “ukuthola umlilo”, uma kunendawo yokuvama engaphezu komkhawulo, kuthathwa ngokuthi “kutholakale umlilo ”. Uhlelo lwendabuko lwe- “Spectrum analyzer + single probe” luvamise ukusetshenziswa ngonjiniyela be-EMI ukuthola ukuthi iyiphi ingxenye yeshashisi ilangabi eleqa kuyo. Lapho kutholwa ilangabi, ukucindezelwa kwe-EMI ngokuvamile kwenziwa ngokuvikela nokuhlunga ukumboza ilangabi ngaphakathi komkhiqizo. I-EMSCAN isivumela ukuthi sithole umthombo wokuphazamiseka, “ukuvutha,” kanye “nomlilo,” okuyindlela yokusabalalisa yokuphazamiseka. Lapho i-EMSCAN isetshenziselwa ukuhlola inkinga ye-EMI yohlelo lonke, inqubo yokulandela ngomkhondo kusuka elangabini kuya elangabini ivame ukwamukelwa. Isibonelo, qala ngokuskena i-chassis noma ikhebuli ukubheka ukuthi ukuphazamiseka kuvela kuphi, bese ulandelela ingaphakathi lomkhiqizo, okuyi-PCB edala ukuphazamiseka, bese ulandelela ucingo noma i-wiring.

Indlela ejwayelekile imi kanjena:

(1) Thola ngokushesha imithombo yokuphazanyiswa kwamandla kagesi. Bheka ukusatshalaliswa kwendawo kwegagasi eliyisisekelo bese uthola indawo ebonakalayo nge-amplitude enkulu ekusabalalisweni kwendawo kwegagasi eliyisisekelo. Ngokuphazamiseka kwe-broadband, chaza imvamisa phakathi kokuphazamiseka kwe-broadband (njengokuphazamiseka kwe-broadband ye-60MhZ-80mhz, singacacisa i-70MHz), uhlole ukusatshalaliswa kwendawo yaleli phuzu lemvamisa, thola indawo ebonakalayo nge-amplitude enkulu.

(2) Cacisa isikhundla bese ubona imephu ye-spectrum yesikhundla. Bheka ukuthi ukuphakama kwephoyinti ngalinye le-harmonic kuleyo ndawo kuhlangana kanjani nobubanzi obuphelele. Uma igqagqene, kusho ukuthi indawo ecacisiwe iyindawo enamandla kakhulu yokukhiqiza lokhu kuphazamiseka. Ukuphazanyiswa kwe-broadband, hlola ukuthi ngabe lesi sikhundla siyisikhundla esiphezulu sakho konke ukuphazamiseka kwe-broadband.

(3) Ezimweni eziningi, akuwona wonke ama-harmoniki akhiqizwa endaweni efanayo, kwesinye isikhathi ngisho nama-harmoniki nama-harmoniki angajwayelekile akhiqizwa ezindaweni ezahlukahlukene, noma ingxenye ngayinye ye-harmonic ingenziwa ezindaweni ezihlukile. Kulokhu, ungathola imisebe enamandla kakhulu ngokubheka ukwabiwa kwendawo kwamaphoyinti wemvamisa obakhathalelayo.

(4) Akungabazeki ukuthi iphumelela kakhulu ukuxazulula izinkinga ze-EMI / EMC ngokuthatha izinyathelo endaweni enemisebe enamandla kakhulu.

Le ndlela yokuthola i-EMI, engalandelela ngempela “umthombo” nomzila wokusabalalisa, yenza onjiniyela bakwazi ukuxazulula izinkinga ze-EMI ngezindleko eziphansi kakhulu futhi ezisheshayo. Endabeni yethuluzi lokuxhumana, lapho imisebe ikhishwa khona ngekhebuli yocingo, kube sobala ukuthi ukufaka ukuvikela noma ukuhlunga ikhebula bekungeke kwenzeke, kushiye onjiniyela bengenakuzisiza. Ngemuva kokuthi i-EMSCAN isetshenziselwe ukulandela umkhondo ongenhla nokuskena, kwasetshenziswa ama-yuan ambalwa ebhodini lokuprosesa kwafakwa ama-capacitor wokuhlunga amaningi, axazulula inkinga ye-EMI onjiniyela abebengenakuyixazulula ngaphambilini. Ukuthola indawo esheshayo yephutha lesifunda Umfanekiso 5: Umdwebo we-Spectrum webhodi ejwayelekile nebhodi lephutha.

Njengoba ubunzima be-PCB bukhula, ubunzima nomthwalo wokulungisa amaphutha nawo uyanda. Nge-oscilloscope noma i-logic analyzer, munye kuphela noma inombolo ekhawulelwe yolayini besiginali engabonwa ngasikhathi, kanti kulezi zinsuku kungaba nezinkulungwane zolayini bezimpawu ku-PCB, futhi onjiniyela kufanele bathembele kulwazi noma ngenhlanhla ukuthola inkinga. Uma “sinemininingwane ephelele ye-electromagnetic” yebhodi elijwayelekile nebhodi elingalungile, singathola i-spectrum engajwayelekile ngokuqhathanisa imininingwane emibili, bese sisebenzisa “umthombo wokuphazamisa ukuthola ubuchwepheshe” ukuthola indawo yemvamisa engajwayelekile i-spectrum, bese singathola ngokushesha indawo nembangela yephutha. Ngemuva kwalokho, ukutholakala kwe “spectrum engajwayelekile” kwatholakala ebalazweni lokwabiwa kwendawo kwepuleti elinamaphutha, njengoba kukhonjisiwe ku-FIG.6. Ngale ndlela, indawo enephutha yayitholwe igridi (7.6mm × 7.6mm), futhi inkinga ingatholakala ngokushesha. Umdwebo 6: Thola indawo ye- “spectrum engajwayelekile” ebalazweni lokwabiwa kwendawo kwepuleti elinamaphutha.

Lesi sifinyezo sendatshana

I-PCB imininingwane ephelele kagesi, ingasivumela ukuba sibe nokuqonda okunembile kwe-PCB yonke, hhayi nje kuphela ukusiza onjiniyela ukuxazulula izinkinga ze-EMI / EMC, kodwa futhi kusiza onjiniyela ukulungisa iphutha le-PCB, futhi bathuthukise njalo ikhwalithi ye-PCB. I-EMSCAN nayo inezicelo eziningi, njengokusiza onjiniyela ukuxazulula izinkinga zokuzwela ngogesi.