PCB bolodi Impedans imatanthawuza magawo a kukana ndi kuchitapo kanthu, zomwe zimalepheretsa kusinthasintha kwapano. Popanga matabwa ozungulira PCB, kukonza kwa impedance ndikofunikira. N’chifukwa chiyani matabwa ozungulira PCB amafunikira impedance?

1. Dongosolo la PCB (pansi pa bolodi) liyenera kuganizira za plugging ndi kukhazikitsa zida zamagetsi, ndipo ma conductivity ndi kutumizira ma siginecha ziyeneranso kuganiziridwa pambuyo poti chigamba cha SMT chatsekedwa. Choncho, kutsika kwa impedance, kumakhala bwino, makamaka chizindikiro cha microwave. Pazida, kufunikira kwa resistivity ndi: zosakwana 1&TImes;10-6 pa lalikulu centimita.

2. Popanga ma board ozungulira a pcb, amayenera kudutsa njira monga kumizidwa mkuwa, plating ya malata (kapena plating yamankhwala, kapena malata opopera amafuta), cholumikizira cholumikizira, etc., ndi zida zomwe zimagwiritsidwa ntchito pazolumikizanazi ziyenera kuwonetsetsa. kuti resistivity ndi otsika, pofuna kuonetsetsa The Impedans wonse wa bolodi dera ndi otsika kukwaniritsa zofunika mankhwala khalidwe ndipo akhoza kugwira ntchito bwinobwino.

Chachitatu, malata plating wa matabwa pcb dera ndi ambiri sachedwa mavuto kupanga gulu lonse dera, ndipo ndi kugwirizana kiyi zimene zimakhudza impedance. Kuwonongeka kwakukulu kwa malata opanda ma elekitirodi ndikosavuta kusinthika (kosavuta kukhala oxidized kapena deliquescent) komanso kusakhazikika bwino, zomwe zingayambitse kusokonekera kwa board board, kutsekeka kwakukulu, kusayenda bwino kwa magetsi, kapena kusakhazikika kwa bolodi lonse.

4. Pali transmissions zosiyanasiyana chizindikiro mu kondakitala wa bolodi pcb dera. Pamene mafupipafupi akuyenera kuwonjezeredwa kuti awonjezere kufalikira kwake, ngati dera lokha ndilosiyana chifukwa cha zinthu monga etching, makulidwe a stack, waya m’lifupi, ndi zina zotero, mtengo wa impedance udzasintha. , Kotero kuti chizindikiro chake chisokonezedwe ndipo ntchito ya bolodi yozungulira ikuwonongeka, choncho m’pofunika kulamulira mtengo wa impedance mkati mwamtundu wina.