He aha ke ʻano o ka bias DC?

I ke kūkulu ʻana i nā capacitors ceramic multilayer (MLCCs), koho pinepine nā ʻenekini uila i ʻelua ʻano dielectric e pili ana i ka noi - Papa 1, non-ferroelectric material dielectrics e like me C0G/NP0, a me Class 2, ferroelectric material dielectrics e like me X5R a me X7R.ʻO ka ʻokoʻa koʻikoʻi ma waena o lākou inā ʻo ka capacitor, me ka piʻi ʻana o ka volta a me ka mahana, mau nō ka paʻa.No ka papa 1 dielectrics, paʻa ka capacitance i ka wā e hoʻohana ʻia ai ka volta DC a piʻi ka mahana hana;ʻO ka papa 2 dielectrics he mau dielectric kiʻekiʻe (K), akā ʻoi aku ka paʻa o ka capacitance ma lalo o nā loli i ka mahana, ka uila, ka pinepine a me ka manawa.

ʻOiai hiki ke hoʻonui ʻia ka capacitance e nā hoʻololi hoʻolālā like ʻole, e like me ka hoʻololi ʻana i ka ʻili o nā papa electrode, ka helu o nā papa, ka waiwai K a i ʻole ka mamao ma waena o nā papa electrode ʻelua, e hāʻule loa ka capacitance o Class 2 dielectrics i ka wā ua hoʻohana ʻia kahi uila DC.Ma muli o ka loaʻa ʻana o kahi mea i kapa ʻia ʻo DC bias, ka mea e ʻike ai ka papa 2 ferroelectric formulations i kahi hāʻule o ka dielectric mau ke hoʻohana ʻia kahi uila DC.

No nā koina K kiʻekiʻe o nā mea dielectric, hiki ke ʻoi aku ka koʻikoʻi o ka hopena o DC bias, me nā capacitors hiki ke nalowale a hiki i ka 90% a ʻoi aku paha o ko lākou kaha, e like me ka hōʻike ʻana ma ke kiʻikuhi.

ʻO ka ikaika dielectric o kahi mea, ʻo ia hoʻi ka volta i hiki ke kū i ka mānoanoa o ka mea i hāʻawi ʻia, hiki ke hoʻololi i ka hopena o ka bias DC ma kahi capacitor.Ma USA, ana pinepine ia ka ikaika dielectric ma volts/mil (1 mil like 0.001 iniha), ma kahi e ana ia ma volts/micron, a ua hooholo ia e ka manoanoa o ka papa dielectric.ʻO ka hopena, hiki ke hana ʻokoʻa nā capacitors like ʻole me ka capacitance like a me ka helu voltage ma muli o ko lākou mau ʻano o loko.

He mea pono e hoʻomaopopo i ka wā i ʻoi aku ka nui o ka volta i hoʻohana ʻia ma mua o ka ikaika dielectric o ka mea, e hele nā ​​hunaahi i loko o ka mea, e alakaʻi ana i kahi hiki ke hoʻā a i ʻole ka pahū liʻiliʻi.

Nā hiʻohiʻona maʻamau o ka hana ʻana o ka bias DC

Inā mākou e noʻonoʻo i ka hoʻololi ʻana o ka capacitance ma muli o ka volta hana i hui pū me ka hoʻololi ʻana i ka mahana, a laila ʻike mākou e ʻoi aku ka nui o ka capacitance o ka capacitor i ka wela noi kikoʻī a me ka uila DC.E lawe i ka laʻana he MLCC i hana ʻia me X7R me ka capacitance o 0.1µF, kahi volta helu o 200VDC, kahi helu o loko o 35 a me ka mānoanoa o 1.8 mils (0.0018 inches a i ʻole 45.72 microns), ʻo ia ke ʻano o ka hana ʻana ma 200VDC ka dielectric. ʻIke wale ka papa i ka 111 volts/mil a i ʻole 4.4 volts/micron.Ma ke ʻano he helu koʻikoʻi, ʻo ka VC he -15%.Inā ʻo ±15%ΔC ka helu wela o ka dielectric a ʻo ka VC -15%ΔC, a laila ʻo +15% - 30%ΔC ka nui o ka TVC.

Aia ke kumu o kēia ʻano hoʻololi i ka ʻano aniani o ka papa 2 i hoʻohana ʻia - ma kēia hihia barium titanate (BaTiO3).Loaʻa kēia mea i kahi ʻano aniani cubic ke hiki i ka mahana Curie a i luna paha.Eia nō naʻe, ke hoʻi ka mahana i ka wela ambient, hiki mai ka polarization i ka hoʻohaʻahaʻa ʻana o ka mahana i mea e hoʻololi ai i kona ʻano.Hana ʻia ka polarization me ka ʻole o ke kahua uila a i ʻole ke kaomi ʻana a ʻike ʻia kēia he polarization spontaneous a i ʻole ferroelectricity.Ke hoʻohana ʻia kahi volta DC i ka mea ma ka wela ambient, pili ka polarization spontaneous i ke kuhikuhi o ke kahua uila o ka volta DC a hoʻohuli ʻia ka polarization spontaneous, e hopena i ka hoʻemi ʻana i ka capacitance.

I kēia mau lā, ʻoiai me nā mea hoʻolālā like ʻole i loaʻa e hoʻonui i ka capacitance, e emi mau ana ka capacitance o ka Class 2 dielectrics i ka wā e hoʻopili ʻia ai kahi uila DC ma muli o ke ʻano o ka hanana DC bias.No laila, i mea e hōʻoiaʻiʻo ai i ka hilinaʻi lōʻihi o kāu noi, pono ʻoe e noʻonoʻo i ka hopena o ka bias DC ma ka ʻāpana me ka capacitance nominal o ka MLCC i ke koho ʻana i kahi MLCC.

ʻO Zhejiang NeoDen Technology Co., LTD., i hoʻokumu ʻia i ka makahiki 2010, he mea hana loea i ka mīkini koho SMT a me kahi mīkini, reflow umu, mīkini paʻi stencil, laina hana SMT a me nā huahana SMT ʻē aʻe.Loaʻa iā mākou kā mākou hui R&D ponoʻī a me ka hale hana ponoʻī, e hoʻohana ana i kā mākou R&D ʻike waiwai ponoʻī, hoʻomaʻamaʻa maikaʻi ʻia, lanakila maikaʻi ʻia mai nā mea kūʻai aku o ka honua.

Ke manaʻoʻiʻo nei mākou he poʻe maikaʻi a me nā hoa hana ʻo NeoDen i ʻoihana maikaʻi a ʻo kā mākou kūpaʻa i ka Innovation, Diversity and Sustainability e hōʻoia i ka loaʻa ʻana o ka automation SMT i kēlā me kēia mea hobbyist ma nā wahi āpau.