Pcb bhodhi impedance inoreva maparamendi ekupikisa uye kuita, izvo zvinotadzisa kuchinjanisa ikozvino. Mukugadzirwa kwePCB redunhu mabhodhi, impedance kugadzirisa kwakakosha. Sei PCB wedunhu mabhodhi achida impedance?

1. Mutambo wePCB (pasi pebhodhi) unofanirwa kufunga nezvekuvhara nekuisa zvikamu zvemagetsi, uye conductivity uye kushanda kwekutumira zviratidzo kunofanirawo kutariswa mushure mokunge chigamba che SMT chikavharwa. Naizvozvo, iyo yakaderera iyo impedance, zviri nani, kunyanya iyo microwave chiratidzo. Pamidziyo, chinodiwa cheresitorendi ndechekuti: isingasviki 1&TImes;10-6 pa square centimita.

2. Mukugadzirwa kwepcb redunhu mabhodhi, vanofanirwa kuenda nenzira dzakadai sekunyudzwa kwemhangura, tin plating (kana kemikari plating, kana thermal spray tin), connector soldering, nezvimwewo, uye zvinhu zvinoshandiswa mune izvi zvinongedzo zvinofanirwa kuve nechokwadi. kuti resistivity yakaderera, kuitira kuti ive nechokwadi Iyo yose impedance yedare redunhu yakaderera kuti isangane nechigadzirwa chemhando yezvinodiwa uye inogona kushanda zvakajairika.

Chechitatu, tin plating pamusoro pcb redunhu mapuranga ndiyo inonyanya kutarisana nezvinetso mukugadzirwa kwebhodhi rose redunhu, uye chinhu chinokosha chinobatanidza impedance. Kukanganisa kukuru kweelectroless tin coating is easy discoloration (nyore kuve oxidized kana deliquescent) uye kushomeka solderability, izvo zvinozotungamira kune yakaoma soldering yedhipatimendi redunhu, yakakwira impedance, kusagadzikana kwemagetsi emagetsi, kana kusagadzikana kwekuita kwebhodhi rose.

4. Pane siyana chiratidzo transmissions ari conductors pamusoro pcb redunhu bhodhi. Kana iyo frequency inofanirwa kuwedzerwa kuitira kuti iwedzere kutapurirana kwayo, kana dunhu pacharo rakasiyana nekuda kwezvinhu zvakaita se etching, stack thick, wire wide, etc., iyo impedance value ichachinja. , Saka kuti chiratidzo chayo chive chakakanganiswa uye kushanda kwebhodhi redunhu kuderedzwa, saka zvakakosha kudzora kukosha kwe impedance mukati mehumwe huwandu.