Ubhedu ngumaleko wesinyithi osebenzayo oqhelekileyo kumphezulu webhodi yesekethe (PCB).Ngaphambi kokuba uqikelele ukuxhathisa kobhedu kwi-PCB, nceda uqaphele ukuba ukuxhathisa ubhedu kuyahluka ngobushushu.Ukuqikelela ukuxhathisa kobhedu kumphezulu we-PCB, le fomula ilandelayo ingasetyenziswa.
Xa ubala ixabiso lokumelana nomqhubi jikelele R, le fomula ilandelayo ingasetyenziswa.
ʅ : ubude bomqhubi [mm]
W: Ububanzi bomqhubi [mm]
t: ubukhulu bomqhubi [μm]
ρ : ukuqhuba kweconductivity [μ ω cm]
Ukumelana nobhedu kuku-25°C, ρ (@ 25°C) = ~1.72μ ω cm
Ukongeza, ukuba uyazi ukuchasana nobhedu kwindawo nganye yeyunithi, i-Rp, kumaqondo okushisa ahlukeneyo (njengoko kubonisiwe kumfanekiso ongezantsi), ungasebenzisa le fomyula ilandelayo ukuqikelela ukuchasana kobhedu lonke, R. Qaphela ukuba imilinganiselo yemilinganiselo ubhedu oluboniswe ngezantsi bubukhulu (t) 35μm, ububanzi (w) 1mm, ubude (ʅ) 1mm.
Rp: ukuxhathisa kwiyunithi yendawo nganye
ʅ: ubude bobhedu [mm]
W: ububanzi bobhedu [mm]
t: ubukhulu bobhedu [μm]
Ukuba imilinganiselo yobhedu yi-3mm ububanzi, i-35μm ngobukhulu kunye ne-50mm ubude, ixabiso lokumelana ne-R yobhedu kwi-25 ° C.
Ngaloo ndlela, xa i-3A yangoku ihamba ngobhedu kwi-PCB ebusweni kwi-25 ° C, i-voltage yehla malunga ne-24.5mV.Nangona kunjalo, xa ubushushu buphakama ukuya kwi-100 ℃, ixabiso lokumelana landa ngama-29% kwaye ukuhla kwamandla ombane kuba yi-31.6mV.
Ixesha lokuposa: Nov-12-2021