Ngokuphuculwa kweemveliso zabathengi, ngokuthe ngcembe ikhula kwicala lobukrelekrele, ngoko ke iimfuno zebhodi ye-PCB yokuphazamiseka ziya ziba ngqongqo ngakumbi, nto leyo ekhuthaza ukukhula okuqhubekayo koyilo lwetekhnoloji ye-impedance.
Yintoni impedance yophawu?
1. Ukuxhatshazwa okwenziwa ngokutshintshana ngoku kumacandelo kuhambelana ne-capacitance kunye ne-inductance. Xa kukho i-electronic signal waveform transmission kwi-conductor, ukuchasana okufumanayo kubizwa ngokuba yi-impedance.
2. Ukuchasana kukuxhathisa okwenziwa ngoku ngokuthe ngqo kumacandelo, ahambelana ne-voltage, resistivity and current.
Ukusetyenziswa kwe-Characteristic Impedance
1. Iimpawu zombane ezinikezelwa yibhodi eprintiweyo esetyenziswe kwi-high-speed signal transmission and high-frequency circuits kufuneka ibe yinto yokuba kungabikho kubonakaliswa okwenzekayo ngexesha lenkqubo yokuhambisa umqondiso, umqondiso uhlala ulungile, ilahleko yokudluliselwa iyancitshiswa, kunye nefuthe elihambelanayo. inokufezekiswa. Isiginali yothumelo egqibeleleyo, ethembekileyo, echanekileyo, engenaxhala, engenangxolo.
2. Ubungakanani be-impedance abunakuqondwa ngokulula. Inkulu ingcono okanye encinci ingcono, isitshixo siyahambelana.
Lawula iiparamitha zokuthintela uphawu
I-dielectric constant yeshiti, ubukhulu bomaleko we-dielectric, ububanzi bomgca, ukutyeba kobhedu, kunye nobukhulu bemaski ye-solder.
Impembelelo kunye nokulawula imaski ye-solder
1. Ubunzima bemaski ye-solder bunempembelelo encinci kwi-impedance. Xa ubukhulu bemaski ye-solder bunyuka nge-10um, ixabiso le-impedance litshintsha kuphela nge-1-2 ohms.
2. Kuyilo, umahluko phakathi kwemaski solder cover kunye non-cover solder imaski mkhulu, single-ephele 2-3 ohms, kunye umahluko 8-10 ohms.
3. Kwimveliso yebhodi ye-impedance, ubukhulu bemaski ye-solder buhlala bulawulwa ngokweemfuno zokuvelisa.
Uvavanyo lwe-impedance
Indlela esisiseko yindlela ye-TDR (i-time domain reflectometry). Umgaqo osisiseko kukuba isixhobo sikhupha isignali ye-pulse, esongwa emva kwiqhekeza lovavanyo lwebhodi yesekethe ukulinganisa utshintsho kwixabiso le-impedance yeempawu zokukhutshwa kunye ne-foldback. Emva kohlalutyo lwekhompyuter, i-impedance yeempawu ziphuma.
Impedance ukusombulula ingxaki
1. Kwimilinganiselo yokulawula i-impedance, iimfuno zokulawula ziyakwazi ukufezekiswa ngokulungelelanisa ngokubambisana kwimveliso.
2. Emva kwe-lamination kwimveliso, ibhodi iyasikwa kwaye ihlalutywe. Ukuba ubukhulu bendawo buncitshisiwe, ububanzi bomgca bunokuncitshiswa ukuhlangabezana neemfuno; ukuba ingqindilili kakhulu, ubhedu lunokunyuswa ukunciphisa ixabiso le-impedance.
3. Kuvavanyo, ukuba kukho umahluko omkhulu phakathi kwethiyori kunye neyona nto, eyona nto inokwenzeka kukuba kukho ingxaki kuyilo lobunjineli kunye noyilo lomgca wovavanyo.
Ixesha lokuposa: Mar-15-2022