He aha te whakahaere aukati me pēhea te whakahaere i te aukati i runga i ngā PCB

I roto i te hoahoa o ngā taputapu hiko hou, he mea nui te mahi a ngā PCB. Ka pā tika te mahi a ngā PCB ki te pumau, te pono me te pai o te tuku o te pūnaha hiko katoa. I roto i ēnei, ko te whakahaere aukati he wāhanga nui o te hoahoa PCB. Nā te mea he poto ake ngā wā tuku tohu me ngā tere karaka teitei ake o ngā ara iahiko matihiko hou, kāore ngā tohu PCB e rite ana ki ngā hononga ngāwari, engari he raina tuku. Ko te whakahaere aukati PCB e pā ana ki te whakahaere i te tere tuku me te taurite aukati o ngā tohu i runga i te PCB hei whakarite i te kounga me te pumau o te tuku tohu.

I ngā āhuatanga mahi, me whakahaere te aukati ara ina teitei ake te tere tawhā mamati i te 1ns, ina neke atu rānei te auau anaro i te 300MHz. Ko tētahi o ngā tawhā matua o te aukati PCB ko tōna aukati āhuatanga (arā, te ōwehenga o te ngaohiko ki te iahiko ina tukuna te ngaru i te rārangi tuku tohu). Ko te aukati āhuatanga o ngā waea i runga i ngā PCB he tohu nui mō te hoahoa PCB. Ina koa i roto i te hoahoa PCB auau teitei, me whakaaro mēnā he rite, he ōrite rānei te aukati āhuatanga o te waea ki te aukati āhuatanga e hiahiatia ana o te taputapu, o te tohu rānei. E rua ngā ariā e uru ana ki tēnei: ​​te whakahaere aukati me te taurite aukati. Ka arotahi tēnei tuhinga ki ngā take o te whakahaere aukati me te hoahoa puranga.

He maha ngā tohu e tukuna ana i roto i ngā kaiārahi o te PCB. Hei whakapai ake i tōna tere tuku, me whakanui ake tōna auau. Ka rerekē te uara ārai o te ara iahiko nā ngā āhuatanga pēnei i te whakairo, te matotoru o te paparanga me te whānui o te waea, ā, ka puta te whakapōturi o te tohu. Nō reira, me whakahaere te uara ārai o ngā kaiārahi i runga i ngā PCB tere-rahi i roto i tētahi awhe, e kiia nei ko te "mana ārai".

Ko te aukati o ngā tohu PCB ka whakatauhia e ō rātou aukume whakaawe me te kaha, te ātete me te tauwehenga kawe hiko. Ko ngā mea e pā ana ki te aukati o te waea PCB ko te whānui me te matotoru o te waea parahi, te pūmau dielectric me te matotoru o te reo, te matotoru o te papa honohono, te ara o te waea whenua, me te waea huri noa i te waea, me ētahi atu. Ko te whānuitanga o te aukati PCB he 25 ki te 120 ohms.

I roto i te mahi, ko ngā raina tuku PCB he mea hanga ki te tohu waea, ki tētahi, ki ētahi atu rānei paparanga tohutoro, me ngā rauemi whakamahana. Ko te tohu me te paparanga te mea e hanga ana i te aukati whakahaere. He maha ngā hanganga paparanga-maha o ngā PCB, ā, ka taea hoki te hanga i te whakahaere aukati i roto i ngā huarahi rerekē. Heoi, ahakoa te tikanga e whakamahia ana, ka whakatauhia te uara aukati e tōna hanganga ā-tinana me ngā āhuatanga hiko o te rauemi whakamahana:

Ko te microstrip he aho waea e pā ana ki tētahi raina tuku hiko me te taha kotahi anake he papa tohutoro. Ka kitea te tihi me ngā taha ki te hau (ka pania rānei) ā, kei runga i te mata o tētahi PCB Er pūmau whakamahana, me te paparanga hiko, te paparanga whenua rānei hei tohutoro. E whakaaturia ana i te pikitia e whai ake nei:

Kia mōhio: I roto i te hanga PCB tūturu, ka pania e te wheketere PCB he paparanga waituhi matomato ki runga i te mata o te PCB. Nō reira, i roto i ngā tataunga aukati tūturu, ko te tauira e whakaaturia ana i te pikitia e whai ake nei ka whakamahia mō ngā raina mata moroiti.

He aho waea te raina rīpene e whakatakotoria ana i waenganui i ngā papa tohutoro e rua, e whakaaturia ana i te pikitia e whai ake nei. Ka rerekē pea ngā pūmau ārai-hiko o te ārai-hiko e tohuhia ana e H1 me H2.

Ko ngā tauira e rua i runga ake nei he whakaaturanga noa iho o ngā raina iti me ngā raina riipene, e whakamahia ana mō te ako i ngā taputapu atamai IoT kua whakauruhia me ētahi atu pūnaha. He maha ngā momo raina iti me ngā raina riipene motuhake, pērā i te raina riipene pania, e pā ana ki te hanganga whakarārangi motuhake o ngā PCB.

Ko te whārite e whakamahia ana hei tatau i te aukati āhuatanga me whai tātaitanga pāngarau uaua, e whakamahi ana i ngā tikanga whakaoti mara, tae atu ki te tātari huānga rohe. Nō reira, mā te whakamahi i te pūmanawa tātai aukati motuhake SI9000, ko tā tātou anake he whakahaere i ngā tawhā o te aukati āhuatanga:

Ko te pūmau dielectric Er o te paparanga whakamahana, te whānui o te waea W1 me te W2 (trapezoidal), te matotoru o te waea T, me te matotoru o te paparanga whakamahana H.

W – te whānui o te rārangi kua hoahoatia

A – te ngaronga o te whakairo (tirohia te ripanga i runga ake nei)

Ko te take o te whānui koretake i waenga i te tihi me te raro o te raina, he mea ka puta te waikura mai i runga ki raro i te wā e hangaia ana ngā PCB, ka hua ake he āhua trapezoidal o te raina kua waikura.

He whanaungatanga rite kei waenganui i te matotoru o te rārangi T me te matotoru parahi o tēnei paparanga, penei:

* Nā te iti o te awe o te matotoru o te kopare whakarewa ki te aukati, e kiia ana he uara pumau o te 0.5mil.

Ka taea e tātou te whakatutuki i te whakahaere ārai mate mā te whakahaere i ēnei tawhā. Hei tauira, mā te whakamahi i te PCB o raro o Anwei, ka whakamāramahia e mātou ngā mahi o te whakahaere ārai mate me te whakamahinga o te SI9000:

Ko te paparanga tuarua ko te papa whenua, ko te paparanga tuarima ko te paparanga mana, ā, ko ngā paparanga e toe ana ko ngā paparanga tohu.

Whakamārama: Ko te parenga hiko i waenganui i ngā paparanga waenga ko FR-4, me te pūmau parenga hiko o te 4.2; Ko ngā paparanga o runga me raro he paparanga tahanga e pā tika ana ki te hau, ā, ko te pūmau parenga hiko o te hau ko 1.

Ka taea e ngā kaihoahoa PCB te whakamahi katoa i te hanganga hierarki o ngā PCB hei whakatutuki i te whakahaere ārai. Mā te whakanoho i ngā paparanga tohu rerekē ki ngā tūranga paparanga rerekē, ka taea te whakahaere pai i te kaha me te ine i waenga i ngā paparanga. I te nuinga o te wā, ka whakamahia e te paparanga o roto ngā rauemi ārai teitei, ā, ka whakamahia e te paparanga o waho ngā rauemi ārai iti hei whakaiti i te pānga o te whakaata me te whakawhitiwhiti kōrero.

Ka taea e ngā raina tuku tohu rerekē te whakarato i te kaha ārai-whakararuraru pai ake me te whakaiti i te mōrearea whakawhitiwhiti kōrero. Ko ngā raina tuku tohu rerekē he takirua waea whakarara me ngā ngaohiko rerekē engari he rite te rahi, ka taea te whakarato i te pono o te tohu me te kaha ārai-whakararuraru pai ake. Ko te aukati o ngā raina tuku tohu rerekē ka whakahaerehia i te nuinga o te wā e te kōwhiringa o te mokowā raina, te whānui me te papa whenua.

Ka taea hoki te whakamahi i ngā tawhā āhuahanga pēnei i te whānui o te rārangi PCB, te mokowā me te tahora hei whakahaere i te aukati. Mō ngā rārangi microstrip noa, ka taea e te whānui o te rārangi matotoru me te mokowā nui ake te whakaiti i te aukati. Mō ngā rārangi coaxial, ka taea e ngā diameter rārangi o roto iti me ngā radius rārangi o waho nui ake te whakanui ake i te aukati. Ko te kōwhiringa o te āhuahanga waea me arotau i runga i ngā whakaritenga aukati motuhake me te auau tohu.

Ka pā anō hoki te pūmau dielectric o ngā rauemi PCB ki te aukati. Ko te whiriwhiri i ngā rauemi me ngā āhuatanga dielectric pumau he wāhanga o te whakahaere aukati. I roto i ngā tono auau teitei me te tere teitei, ko ngā rauemi e whakamahia whānuitia ana ko te FR-4 (papa whakakaha muka karāhe), te PTFE (polytetrafluoroethylene), me ngā papa RF (auau reo irirangi).

I mua i te hoahoa PCB, mā te whakamahi i ngā taputapu whakatauira me te hoahoa ka taea e ngā kaihoahoa te manatoko me te arotau tere me te tika i te aukati. Ka taea e ēnei taputapu te whakatauira i te whanonga ara iahiko, ngā ngaronga tuku tohu me ngā taunekeneke hikohiko hei whakatau i ngā tawhā hoahoa PCB tino pai. Ko ētahi o ngā taputapu whakatauira noa ko CST Studio Suite, HyperLynx me ADS.

He mea nui te whakahaere ārai mate PCB i roto i ngā ara iahiko matihiko me te ara iahiko anarau tere-teitei. Mā te hoahoa hierarki whaitake, te whakamahi i ngā raina tuku tohu rerekē, te whakahaere i te āhua waea, te whiriwhiri i ngā rauemi PCB e tika ana, me te whakamahi i ngā taputapu whakatauira me te hoahoa, ka taea te whakatutuki i te whakahaere ārai mate tika, ā, mā reira ka whakapai ake i te mahi ara iahiko me te pono o te tohu.