Intambwe yambere nugukora ihitamo ryaMOSFETS, biza muburyo bubiri: N-umuyoboro na P-umuyoboro. Muri sisitemu yingufu, MOSFETs irashobora gutekerezwa nkumuriro wamashanyarazi. Iyo voltage nziza yongeyeho hagati y irembo nisoko ya N-umuyoboro MOSFET, switch yayo ikora. Mugihe cyo gutwarwa, imiyoboro irashobora gutembera muri switch kuva kumugezi kugera kumasoko. Habaho kurwanya imbere hagati yamazi nisoko yitwa on-resistance RDS (ON). Hagomba kumvikana neza ko irembo rya MOSFET ari itambuka ryinshi, bityo voltage yongerwa kumuryango. Ubu ni ukurwanya hasi irembo rihujwe nigishushanyo cyumuzingi cyatanzwe nyuma. Niba irembo risigaye rimanitse, igikoresho ntigikora nkuko cyateganijwe kandi gishobora gufungura cyangwa kuzimya mugihe kidakwiye, bikaviramo gutakaza ingufu muri sisitemu. Iyo voltage iri hagati yinkomoko n irembo ari zeru, switch irazimya kandi ihagarara ryanyuze mubikoresho. Nubwo igikoresho cyazimye aho bigeze, haracyari akantu gato gahari, bita akuma kameneka, cyangwa IDSS.
Intambwe ya 1: Hitamo N-umuyoboro cyangwa P-umuyoboro
Intambwe yambere muguhitamo igikoresho gikwiye kubishushanyo ni uguhitamo gukoresha N-umuyoboro cyangwa P-umuyoboro MOSFET. mubisanzwe imbaraga zikoreshwa, mugihe MOSFET ihagaze kandi umutwaro uhujwe na trunk voltage, iyo MOSFET igizwe na voltage ntoya kuruhande. Muri voltage ntoya kuruhande, N-umuyoboroBYINSHIbigomba gukoreshwa bitewe no gusuzuma voltage isabwa kuzimya cyangwa kuzimya igikoresho. Iyo MOSFET ihujwe na bisi hanyuma umutwaro ugahagarara, impinduka nini ya voltage kuruhande igomba gukoreshwa. Imiyoboro ya P-MOSFET isanzwe ikoreshwa muri iyi topologiya, na none kubitekerezo bya voltage.
Intambwe ya 2: Menya igipimo kiriho
Intambwe ya kabiri ni uguhitamo igipimo cyubu cya MOSFET. Ukurikije imiterere yumuzunguruko, uru rutonde rugomba kuba urwego ntarengwa umutwaro ushobora kwihanganira mubihe byose. Bisa nikibazo cya voltage, uwashizeho agomba kwemeza ko MOSFET yatoranijwe ishobora kwihanganira iki gipimo cyubu, nubwo sisitemu itanga imigezi ya spike. Imanza ebyiri zubu zasuzumwe nuburyo bukomeza nuburyo bwa pulse. Iyi parameter ishingiye kuri tube ya FDN304P DATASHEET nkibisobanuro kandi ibipimo byerekanwe mubishusho:
Muburyo bukomeza bwo gutwara, MOSFET ihagaze neza, mugihe ikigenda gitemba binyuze mubikoresho. Imitsi ya pulse ni mugihe hari umubare munini wo kwiyongera (cyangwa umuyoboro wa spike) unyura mubikoresho. Iyo imiyoboro ntarengwa iri muri ibi bihe imaze kugenwa, ni ikibazo cyo guhitamo igikoresho gishobora kwihanganira iyi miyoboro ntarengwa.
Nyuma yo guhitamo ibipimo byagenwe, ugomba no kubara igihombo cya conduction. Mu myitozo ,.BYINSHIntabwo igikoresho cyiza, kuko mubikorwa byo kuyobora hazabaho gutakaza ingufu, aribyo bita igihombo. BYINSHI muri "kuri" nkibishobora guhinduka, bigenwa na RDS (ON) igikoresho, hamwe nubushyuhe nimpinduka zikomeye. Gukwirakwiza ingufu z'igikoresho birashobora kubarwa kuva Iload2 x RDS (ON), kandi kubera ko kurwanywa bigenda bitandukana n'ubushyuhe, ikwirakwizwa ry'amashanyarazi riratandukanye. Iyo hejuru ya voltage VGS ikoreshwa kuri MOSFET, ntoya RDS (ON) izaba nto; muburyo buhanitse RDS (ON) izaba. Kubushakashatsi bwa sisitemu, aha niho hacururizwa ibicuruzwa bitewe na voltage ya sisitemu. Kubishushanyo mbonera, biroroshye (kandi nibisanzwe) gukoresha voltage yo hasi, mugihe kubishushanyo mbonera byinganda, imbaraga zishobora gukoreshwa. Menya ko kurwanya RDS (ON) kuzamuka gato hamwe nubu. Guhindagurika mubintu bitandukanye byamashanyarazi ya RDS (ON) murwanya urashobora kubisanga mumpapuro yamakuru ya tekiniki yatanzwe nuwabikoze.
Intambwe ya 3: Menya Ibisabwa Ubushyuhe
Intambwe ikurikira muguhitamo MOSFET ni ukubara ubushyuhe bwa sisitemu. Ibishushanyo mbonera bigomba gusuzuma ibintu bibiri bitandukanye, urubanza rubi nukuri. Kubara kubintu bibi-byabaye birasabwa kuko iki gisubizo gitanga intera nini yumutekano kandi ikemeza ko sisitemu itazatsindwa. Hariho kandi ibipimo bimwe na bimwe ugomba kumenya kurupapuro rwa MOSFET; nkubushyuhe bwumuriro hagati ya semiconductor ihuza ibikoresho bipakiye nibidukikije, hamwe nubushyuhe ntarengwa.
Ubushyuhe bwihuza bwibikoresho bingana nubushyuhe ntarengwa bwibidukikije hiyongereyeho ibicuruzwa byo kurwanya ubushyuhe hamwe no gukwirakwiza ingufu (ubushyuhe bwihuza = ubushyuhe ntarengwa bw’ibidukikije + [kurwanya ubushyuhe × gukwirakwiza imbaraga]). Uhereye kuri iri gereranya imbaraga ntarengwa zo gukwirakwiza sisitemu zirashobora gukemurwa, ni mubisobanuro bingana na I2 x RDS (ON). Kubera ko abakozi bagennye icyerekezo ntarengwa kizanyura mu gikoresho, RDS (ON) irashobora kubarwa kubushyuhe butandukanye. Ni ngombwa kumenya ko mugihe ukorana nuburyo bworoshye bwubushyuhe, uwashizeho ibishushanyo agomba no gutekereza kubushyuhe bwubushyuhe bwa semiconductor ihuza / igikoresho cyibikoresho hamwe nurubanza / ibidukikije; ni ukuvuga, birasabwa ko ikibaho cyumuzingo cyacapwe hamwe na paki bidashyuha ako kanya.
Mubisanzwe, PMOSFET, hazabaho diode ya parasitike ihari, imikorere ya diode nugukumira inkomoko-imiyoboro ihinduka, kuri PMOS, akarusho kurenza NMOS nuko voltage yayo ishobora kuba 0, kandi itandukaniro rya voltage hagati ya Umuvuduko wa DS ntabwo ari mwinshi, mugihe NMOS kumiterere isaba ko VGS iruta urwego, ibyo bizaganisha kuri voltage yo kugenzura byanze bikunze iruta ingufu zisabwa, kandi hazabaho ibibazo bitari ngombwa. PMOS yatoranijwe nkigenzura rya porogaramu ebyiri zikurikira:
Ubushyuhe bwihuza bwibikoresho bingana nubushyuhe ntarengwa bwibidukikije hiyongereyeho ibicuruzwa byo kurwanya ubushyuhe hamwe no gukwirakwiza ingufu (ubushyuhe bwihuza = ubushyuhe ntarengwa bw’ibidukikije + [kurwanya ubushyuhe × gukwirakwiza imbaraga]). Uhereye kuri iri gereranya imbaraga ntarengwa zo gukwirakwiza sisitemu zirashobora gukemurwa, ni mubisobanuro bingana na I2 x RDS (ON). Kuva uwashizeho igenamigambi ntarengwa rizanyura mu gikoresho, RDS (ON) irashobora kubarwa kubushyuhe butandukanye. Ni ngombwa kumenya ko mugihe ukorana nuburyo bworoshye bwubushyuhe, uwashizeho ibishushanyo agomba no gutekereza kubushyuhe bwubushyuhe bwa semiconductor ihuza / igikoresho cyibikoresho hamwe nurubanza / ibidukikije; ni ukuvuga, birasabwa ko ikibaho cyumuzingo cyacapwe hamwe na paki bidashyuha ako kanya.
Mubisanzwe, PMOSFET, hazabaho diode ya parasitike ihari, imikorere ya diode nugukumira inkomoko-imiyoboro ihinduka, kuri PMOS, akarusho kurenza NMOS nuko voltage yayo ishobora kuba 0, kandi itandukaniro rya voltage hagati ya Umuvuduko wa DS ntabwo ari mwinshi, mugihe NMOS kumiterere isaba ko VGS iruta urwego, ibyo bizaganisha kuri voltage yo kugenzura byanze bikunze iruta ingufu zisabwa, kandi hazabaho ibibazo bitari ngombwa. PMOS yatoranijwe nkigenzura rya porogaramu ebyiri zikurikira:
Urebye uyu muzunguruko, ikimenyetso cyo kugenzura PGC igenzura niba V4.2 itanga ingufu kuri P_GPRS. Uyu muzunguruko, inkomoko hamwe nuyoboro wamazi ntaho bihuriye ninyuma, R110 na R113 birahari muburyo R110 igenzura irembo rinini ntabwo ari rinini cyane, R113 igenzura irembo ryibisanzwe, R113 ikurura ikagera hejuru, nkuko PMOS yabitangaje . kuzimya, muri iki gihe, birakenewe kuri voltage yo hanze ihabwa gukurura, bityo ristoriste R113 ikina inshingano ebyiri. Bizakenera voltage yo hanze kugirango itange gukurura, bityo résistor R113 ikina inshingano ebyiri. r110 irashobora kuba nto, kugeza 100 oms irashobora kandi.
Igihe cyo kohereza: Apr-18-2024
