3-A Synchronous Step-Down Voltage Converter Integrated circuit IC LMR33630BQRNXRQ1

1.

Mosebetsi oa buck converter ke ho fokotsa motlakase oa ho kenya letsoho le ho o bapisa le mojaro.The topology ea mantlha ea converter ea buck e na le switch e kholo le switch ea diode e sebelisoang nakong ea khefu.Ha MOSFET e hokahantsoe ka ho bapa le "continuity diode", e bitsoa "synchronous buck converter".Bokhoni ba sebopeho sena sa buck converter bo phahame ho feta ba li-converter tsa buck tsa nakong e fetileng ka lebaka la khokahano e bapileng ea MOSFET ea lehlakore le tlase le diode ea Schottky.Setšoantšo sa 1 se bonts'a schematic ea synchronous buck converter, e leng mokhoa o tloaelehileng haholo o sebelisoang lik'homphieutha tsa desktop le libuka kajeno.

2.

Mokhoa oa motheo oa ho bala

Li-transistor switch Q1 le Q2 ka bobeli ke li-MOSFET tsa matla a N-channel.li-MOSFET tsena tse peli hangata li bitsoa li-switches tse lehlakoreng le holimo kapa tse tlase 'me MOSFET e lehlakoreng le tlase e hokahantsoe ka ho bapa le diode ea Schottky.Li-MOSFET tsena tse peli le diode li theha mocha o moholo oa matla oa converter.Litahlehelo likarolong tsena le tsona ke karolo ea bohlokoa ea tahlehelo eohle.Boholo ba filthara ea LC bo ka khethoa ke motlakase oa ripple le voltage ea ripple.Ho ipapisitsoe le PWM e sebelisitsoeng molemong o mong le o mong, marang-rang a hanyetsang maikutlo a R1 le R2 a ka khethoa 'me lisebelisoa tse ling li na le ts'ebetso ea ho beha mabaka bakeng sa ho beha motlakase o tsoang.PWM e tlameha ho khethoa ho latela boemo ba matla le ts'ebetso ea ts'ebetso ka lebelo le lakatsehang, ho bolelang hore ha lebelo le eketseha, ho hlokahala hore ho be le bokhoni bo lekaneng ba ho khanna liheke tsa MOSFET, tse etsang palo e fokolang ea likarolo tse hlokahalang. bakeng sa converter e tloaelehileng ea buck ea synchronous.

Moqapi o lokela ho qala ho hlahloba litlhoko, ke hore V input, V output le I output hammoho le litlhoko tsa mocheso o sebetsang.Litlhokahalo tsena tsa mantlha li kopanngoa le phallo ea matla, khafetsa, le litlhoko tsa boholo ba 'mele tse fumanoeng.

3.

Karolo ea li-topology tsa buck-boost

Li-topology tsa buck-boost li sebetsa hobane motlakase oa ho kenya o ka ba o monyenyane, o moholo, kapa o tšoana le motlakase o tsoang ha o ntse o hloka matla a tsoang ho feta 50 W. Bakeng sa matla a tlhahiso a ka tlaase ho 50 W, mochine o motlakase oa motlakase o le mong (SEPIC). ) ke khetho e ntle haholo kaha e sebelisa likarolo tse fokolang.

Li-converter tsa buck-boost li sebetsa ka mokhoa oa buck ha motlakase oa ho kenya o le moholo ho feta motlakase oa tlhahiso le ka mokhoa oa boost ha motlakase oa ho kenya o le ka tlase ho motlakase o tsoang.Ha converter e sebetsa sebakeng sa phetisetso moo motlakase oa motlakase o leng teng sebakeng sa phallo ea motlakase, ho na le menahano e 'meli ea ho sebetsana le maemo ana: ekaba mekhahlelo ea buck le boost e sebetsa ka nako e le ngoe, kapa li-switching cycles li fapanyetsana lipakeng tsa buck. le methati ea boost, e 'ngoe le e 'ngoe e atisa ho sebetsa ka halofo ea maqhubu a tloaelehileng a ho fetoha.Mohopolo oa bobeli o ka baka lerata la sub-harmonic sephethong, athe ho nepahala ha motlakase ho ka 'na ha se ke ha nepahala ha ho bapisoa le ts'ebetso e tloaelehileng ea buck kapa boost, empa converter e tla sebetsa hantle haholo ha e bapisoa le mohopolo oa pele.