Capacitor ESR le ESL: Tataiso ea Bohlokoa bakeng sa Moralo oa Potoloho

Selelekela

Capacitor ESR (Equivalent Series Resistance) le ESL (Equivalent Series Inductance) ke lintho tsa likokoana-hloko tse fokotsang ts'ebetso ea capacitor lipotolohong tsa 'nete tsa lefatše. ESR e emela tahlehelo e hanyetsanang ka har'a sebopeho sa capacitor, ha ESL e hlaha ho tloha boitšoarong ba inductive ba loto, lipoleiti le litsela tsa hona joale.

Likokoana-hloko tsena li ama ka ho toba botsitso ba seporo sa motlakase, katleho ea ho phunya, khatello ea lerata le taolo ea tšitiso ea motlakase. Sengoliloeng sena se fana ka pono e sebetsang ea boenjiniere mabapi le li-capacitor parasitics, mekhoa ea ho lekanya, le maano a moralo ho ntlafatsa ts'ebetso ea potoloho.

Ho utloisisa Capacitor Parasitics: The Equivalent Circuit

Li-capacitor tsa 'nete li fapana haholo le boitšoaro bo botle ka lebaka la likarolo tsa likokoana-hloko. Mohlala o tloaelehileng oa potoloho e lekanang o emela capacitor e le capacitance e ntle ka tatellano le ESR le ESL, ka khanyetso ea ho lutla e bakileng tahlehelo ea DC.

Tšimoloho ea 'Mele ea Capacitor ESR

ESR e simoloha tahlehelong ea dielectric, resistivity ea electrode, le resistance ea ho kopana le lipheletsong le manonyellong a solder. Karolo ea resistivity e hlaha haholo-holo ho tsoa ho dissipation factor ea dielectric ho li-capacitor tsa ceramic le tsa filimi. Li-capacitor tsa electrolytic li kenya letsoho khanyetsong e eketsehileng ka ho tsamaisa motlakase oa electrolyte le thepa ea lera la oxide. Ho felisoa ha metallization le boleng ba manonyello a solder li ama ESR ka kakaretso haholo, haholo-holo lisebelisoa tse kenngoang holim'a metsi.

Tšimoloho ea 'Mele ea Capacitor ESL

ESL e hlaha ho tsoa tšimong ea makenete e hlahisoang ke motlakase o phallang ka har'a lipoleiti tsa capacitor, li-lead le likhokahano. Jiometri ea sephutheloana le bolelele ba lead li khetholla boholo ba ESL. 0805 MLCC hangata e bontša 0.5 nH ESL, ha radial electrolytic e nang le li-lead tse telele e ka feta 15 nH. Sebopeho sa poleiti ea ka hare le sebaka sa terminal li khetholla ESL ho MLCC, ka meralo ea jiometri e ka morao e fanang ka inductance e tlase.

Capacitor ESR ke eng? Tlhaloso e Felletseng

ESR e lekanya phepelo ea matla joalo ka mocheso ha hajoale AC e phalla ka capacitor. Lentsoe lena le hanyetsang le hlaha ka letoto le nang le bokhoni bo loketseng 'me le fapana ho ea ka makhetlo, mocheso le botsofali. Ka maqhubu a tlase, tangent ea tahlehelo ea dielectric e laola boits'oaro ba ESR, ha li-electrode le ho hanyetsa khokahano li fetoha tsa bohlokoa maemong a holimo. Ho itšetleha ka mocheso ho fapana ho ea ka mofuta oa capacitor, ka li-electrolytic capacitor tse bonts'ang ESR e eketseha ka mocheso o tlase ha viscosity ea electrolyte e ntse e phahama.

Litšobotsi tsa ESR ka Mofuta oa Capacitor

Litheknoloji tse fapaneng tsa capacitor li bonts'a lintlha tse fapaneng tsa ts'ebetso ea ESR:

• Li-capacitor tsa MLCC - ESR e tlase haholo ka tlase ho 10 milliohm ka maqhubu a ts'ebetso a reriloeng, leha ts'epo ea DC le litlamorao tsa piezoelectric li ka fetola ts'ebetso.
• Aluminium electrolytic capacitors - ESR e phahameng ho tloha ho li-millione tse 50 ho isa ho li-ohm tse 'maloa ho itšetlehile ka boleng le litekanyetso tsa motlakase, ka kutloisiso e kholo ea mocheso.
• Li-capacitor tsa Tantalum - Ts'ebetso e leka-lekaneng ea ESR empa e hloka ho theoleloa ka hloko ha motlakase ho thibela mekhoa e sa sebetseng ea koluoa.
• Li-capacitors tsa polymer - Kopanya ESR e tlase le botsitso bo botle ba mocheso, o etsa hore e khahle bakeng sa ho sefa phepelo ea motlakase.

Liphello tse sebetsang tsa ESR e phahameng

ESR e phahameng e hlahisa tahlehelo ea I²R e hlahisang mocheso, e potlakisang botsofali ba capacitor mme e ka bakang ho baleha ha mocheso mefuteng ea electrolytic. Ripple voltage ho pholletsa le ESR e theola taolo ea phepelo ea motlakase mme e eketsa tlhahiso ea motlakase. ESR e fana ka damping maqhubu a capacitor self-resonant, e ka thusang ho tsitsisa li-loops tsa maikutlo ho li-switching regulators. Leha ho le joalo, ESR e feteletseng e fokotsa ts'ebetso ea ho sefa le ho fokotsa matla a karabo ea nakoana ha ho kopanngoa lits'ebetso.

Capacitor ESL ke eng? Tlhaloso e Felletseng

ESL e emela ho kenella ha dikokwana-hloko tse teng kahong ya capacitor le tlhophisong ya ho kenya. Ho arabela hona ho inductive ho eketseha ka makgetlo ho ya ka XL = 2πfL, qetellong ho laola pheneho ya capacitor maqhubung a phahameng. ESL e kopana le capacitance ho theha potoloho ya letoto la resonant e nang le makgetlo a idumellanang le ho idumella (SRF) moo di-reactance tse inductive le capacitive di hlakolang.

Phapang ea ESL ka Mofuta oa Pakete

Surface-mount chip capacitor e fokotsa ESL ka compact geometry le litsela tse khutšoane tsa hajoale. 0402 MLCC hangata e bonts'a 0.3-0.5 nH ESL, ha liphutheloana tse kholoanyane tsa 1206 li ka fihla ho 1-2 nH. Li-capacitor tsa radial lead electrolytic capacitor li na le bothata ba ho inductance lead, hangata li feta 10-20 nH ho latela bolelele ba lead. Liphutheloana tse khethehileng tsa Low-ESL li sebelisa li-terminals tse ngata kapa mekhoa ea li-electrode tse kopantsoeng ho fokotsa sebaka sa hona joale sa loop le ho finyella ts'ebetso ea sub-500 pH.

Tšusumetso ea ESL ho Ts'ebetso ea Potoloho

ESL e fokotsa katleho ka ho theha letoto la impedance e thibelang ho tsamaisoa ha hona joale ka potlako nakong ea meroalo ea nakoana. Maqhubu a ikemetseng a theha moeli o kaholimo bakeng sa boits'oaro bo sebetsang ba capacitive, ka impedance e nyolohang kaholimo ho SRF. Multiple parallel capacitor e ka bonts'a mathata a anti-resonance moo ESL le capacitance li hlahisang litlhoro tse sa batleheng tsa impedance. Li-circuits tse feto-fetohang tse phahameng li hlahisa li-spikes tsa hajoale tse sebelisanang le ESL ho hlahisa li-spikes tsa voltage le tšitiso ea motlakase.

Capacitor ESR le ESL: Impedance vs Frequency Behavior

Boholo ba impedance ea Capacitor bo latela libaka tse tharo tse ikhethileng tse khethiloeng ke bolaoli ba likokoana-hloko. Ka tlas'a maqhubu a ho itšehla thajana, capacitive reactance (1/2πfC) e fokotseha ka maqhubu a ntseng a eketseha. Ho SRF, li-capacitive le inductive reactances li hlakola, ho siea ESR feela ho fumana hore na ho na le tšitiso e fokolang. Ka holim'a SRF, inductive reactance (2πfL) e laola, e bakang hore impedance e phahame ha karolo e itšoara joaloka inductor.

Ho Utloisisa Self-Resonant Frequency

Maqhubu a ikemetseng a hlaha ho f = 1 / (2π√LC) moo capacitor e bonts'ang impedance e fokolang e lekanang le ESR. 10 µF MLCC e nang le 0.5 nH ESL e utloahala haufi le 7 MHz, ha 100 µF electrolytic e nang le 15 nH ESL e na le SRF e ka bang 400 kHz. Kamano ena e hlalosa hore na ke hobane'ng ha li-capacitor tsa boleng bo boholo li iponahatsa li sa sebetse bakeng sa ho fokotseha ha maqhubu a phahameng, ho hloka hore ho be le motsoako o tšoanang oa litekanyetso tse fapaneng tsa capacitor bakeng sa taolo ea ho thibela maqhubu a Broadband.

Ho Toloka Lipolanka tsa Impedans

Logarithmic impedance khahlano le makhetlo a mangata a senola li-curve tse nang le sebopeho sa V tse nang le ntlha e nyane ho SRF. Moepa o theohang ka ho le letšehali o bontša ts'ebetso ea capacitive e nang le -20 dB/decade gradient, ha moepa o nyolohang ka ho le letona o bontša boitšoaro bo matla ho +20 dB/decade. ESR e batalatsa phula ea impedance ha resonance, ka ESR e phahameng e hlahisa litšoaneleho tse pharaletseng, tse sa tebang.

Kamoo Capacitor ESR & ESL E Amang Ts'ebetso ea Potoloho

Ho sebetsa hantle ha phepelo ea motlakase ho ipapisitse le ho fokotsa sekhahla lipakeng tsa liporo tsa motlakase ho pholletsa le maqhubu. ESL e fokotsa lebelo la karabelo la nakoana ka ho thibela matla a di/dt, ho baka ho theoha ha motlakase nakong ea mehato e potlakileng ea mojaro. Sesebelisoa sa switching se nang le 1 A ripple current le 100 milliohm output capacitor ESR se ba le 100 mV e eketsehileng ea ripple voltage ho feta fundamental capacitive ripple.

Buck Converter Stability le ESR

Output capacitor ESR e theha zero ts'ebetsong ea phetisetso ea loop e amang marang-rang a botsitso le leano la matšeliso. ESR e tlase haholo e felisa zero ena, e ka 'nang ea hloka likarolo tse eketsehileng tsa matšeliso ho boloka moeli o lekaneng oa mohato. Meralo e tloaelehileng e shebana le ESR ho 10-50 milliohm ho fana ka damping e molemo ha e ntse e boloka ts'ebetso e ntle ea ripple.

EMI le High-Frequency Switching Lerata

Li-parasitics tsa capacitor li susumetsa ka kotloloho maemo a tlhahiso ea motlakase. ESL e lumellana le li-inductances tsa potoloho ho etsa hore ho lla ha ho fetoha, ho hlahisa lerata la Broadband RF. Khokahano e mpe ka lebaka la ESL e feteletseng e lumella lerata la seporo ho batho ba babeli ho ea methating e bobebe ea analoge kapa ho khanya ho tsoa ho mesaletsa ea PCB. Khetho e nepahetseng ea capacitor le ho beoa ho fokotsa likhase tse tsamaisoang le tse hlahisoang ke mahlaseli.

Thermal Stress le Electrolytic Capacitor Botsofali

Hajoale ripple e phallang ka ESR e hlahisa mocheso oa I²R o potlakisang botsofali ba electrolytic capacitor ka mouoane oa electrolyte. Baetsi ba hlakisa lintlha tse ngata tsa hona joale tsa ripple tse ipapisitseng le mocheso o amohelehang oa ts'ebetso le lipakane tsa bophelo bohle. Li-capacitor tsa polymer li mamella maqhubu a phahameng a ripple ka lebaka la ESR e tlase le botsitso bo betere ba mocheso.

Mokhoa oa ho lekanya Capacitor ESR le ESL

Tekanyo e nepahetseng ea ESR le ESL e hloka lisebelisoa tse nepahetseng le mokhoa oa tlhahlobo. Limithara tsa LCR li fana ka litekanyo tsa mantlha tsa impedance ka maqhubu a ikhethileng. Bahlahlobisisi ba Impedans ba fiela mekhahlelo ea maqhubu ho senola litšobotsi tse felletseng tsa impedance ho kenyelletsa le maqhubu a boits'oaro. Limithara tse khethehileng tsa ESR li shebisisa tekanyo ea ESR ea maqhubu a tlase bakeng sa tlhahlobo ea electrolytic capacitor, ha li-vector network analyzer li fana ka sebopeho se nepahetseng sa maqhubu a holimo.

Methati ea ho Seta le Litokiso tsa Teko

Likhokahano tsa Kelvin tse nang le terata e mene li felisa khanyetso ea lead lead le inductance ho tsoa litekanyong, e leng ea bohlokoa bakeng sa liphetho tse nepahetseng tse tlase tsa impedance. Lisebelisoa tsa coaxial li fokotsa ho kenella ha likokoana-hloko le bokhoni ba litekanyo tse ka holimo ho 10 MHz. Litekanyo tsa potoloho li hapa ts'ebetso ea 'nete e kentsoeng empa li na le tšitiso ea tsela e ts'oanang. Teko ea kantle ho potoloho e fana ka liphetho tse hloekileng empa e kanna ea se ke ea bonts'a boleng ba kopanelo ea solder le litlamorao tse ntseng li eketseha.

Ho ntša ESR le ESL ho Measurements

Mekhoa ea bohlokoa ea ho lekanya ho ntša boleng ba parasitic:

• Ho tlosoa ha ESR - Boholo ba impedance ka makhetlo a mangata a ikemetseng a hlahisa ESR ka kotloloho e le boleng bo tlase ba impedance.
• Palo ea ESL - Lekanya impedance ka holimo ho SRF moo karabelo ea inductive e busang, o sebelisa L = Z/(2πf).
• Ho kenya mokoloko - Bahlahlobisisi ba sejoale-joale ba impedans ba lekana lintlha tse lekantsoeng ho mefuta e lekanang ea potoloho, ho ntša ESR le ESL ka nako e le 'ngoe.
• Litlhoko tsa ho lekanya - Calibration e bulehileng ea potoloho e tlosa inductance ea fixture le capacitance; khaloriso ea potoloho e khuts'oane e etsa hore ho be le khanyetso e setseng.

Likotsi tse Tloaelehileng tsa Tekanyo

Khanyetso ea ho ikopanya le lisebelisoa tsa liteko e ka eketsa li-milliohm ho litekanyo tsa ESR, haholo-holo bakeng sa likarolo tse holim'a metsi tse nang le liphetho tse nyane. Mocheso o ama ESR haholo ho li-capacitor tsa electrolytic, tse hlokang tikoloho ea teko e laoloang ke mocheso. Litlamorao tsa botsofali li bolela hore litekanyo tse ncha tsa likarolo li kanna tsa se ke tsa bonts'a ts'ebetso ea nako e telele, e hlokang tlhahlobo ea nako le nako bakeng sa lits'ebetso tsa bohlokoahali.

Merero ea ho Rala ho Fokotsa Capacitor ESR & ESL

Khetho ea likarolo e theha motheo oa taolo e sebetsang ea likokoana-hloko. Li-ceramic capacitor tsa ESR tse tlase li sebetsa hantle haholo ha li-decoupling tse phahameng haholo, ha li-polymer capacitor li fana ka ESR e tlase ho pholletsa le mefuta e mengata ea maqhubu. Li-capacitor tse nyane tse tšoanang hangata li fana ka ts'ebetso e ntle ho feta li-capacitor tse kholo ka ho fokotsa ESL e sebetsang. Ho kopanya mefuta ea li-capacitor ho li-parallel leverages tse tlatselletsang khafetsa.

Mekhoa ea Moralo ea PCB bakeng sa ESL e tlase

Litloaelo tse bohlokoa tsa moralo ho fokotsa litlamorao tsa parasitic:

• Fokotsa sebaka sa loop – Sebaka li-decoupling capacitors hang-hang haufi le lithakhisa tsa motlakase tsa IC tse nang le mesaletsa e tobileng, e pharaletseng kapa lifofane.
• Ka tsamaiso - E 'ngoe le e' ngoe ka tsela e eketsa 0.5-1 nH inductance; fokotsa ka ho bala litseleng tsa morao-rao tse phahameng kapa u sebelise li-vias tse ngata ka ho bapisa.
• Ntlafatso ea sefofane sa fatše - Ho tšela koporo e tsoelang pele le ho ba haufi le sefofane ho fokotsa tsela ea ho khutla.
• Lipontšo tsa litsela - Qoba ho tsamaisa mats'oao a lebelo le phahameng haufi le li-decoupling capacitor ho thibela lerata le kopanyang ka li-capacitor parasitics.

Boleng ba Kopano le Solder Joint Effects

Solder joint geometry e ama haholo ESR le ESL e sebetsang ka ho eketsa khanyetso le sebopeho sa tsela ea hajoale. Solder e feteletseng e etsa li-loops tse kholoanyane le ho eketsa inductance, ha solder e sa lekaneng e phahamisa khanyetso ea ho kopana. Ho kopanya ka holim'a metsi ka tlhaho ho fokotsa bolelele ba loto ha ho bapisoa le kaho ea mekoti. Bakeng sa lits'ebetso tse mahlonoko, tlhahlobo ea X-ray e netefatsa boleng bo kopaneng ba solder.

Mekhoa ea Potoloho ea Tsamaiso ea Parasitic

Series damping resistors ka har'a 1-10 ohm range e hatella litlhōrō tse llang le anti-resonance ka motsoako o tšoanang oa capacitor. Li-snubbers tsa RC ho pholletsa le li-switching node li monya matla ho tsoa ho li-resonances tsa parasitic le ho fokotsa maqhubu a motlakase. Lifaha tsa Ferrite li eketsa letoto la impedance ka maqhubu a phahameng ha li ntse li boloka khanyetso e tlase ea DC. Ho fokotseha ha likarolo ho netefatsa ts'ebetso e ts'epahalang tlas'a maemo a mabe ka ho fetesisa, ho lelefatsa bophelo bohle ba li-capacitor tsa electrolytic.

Capacitor ESR & ESL ka Mofuta: Reference Values

Litekanyetso tsena li emela maemo a tloaelehileng a tatellano ea boholo molemong oa litšupiso. Ha e le hantle capacitor ESR le ESL li fapana haholo ka nomoro ea karolo e itseng, boleng ba matla, tekanyo ea motlakase le moetsi. Baqapi ba tlameha ho sheba lipampiri tse felletseng bakeng sa lintlha tse hlakileng. Thempereichara, khafetsa, voltage ea leeme la DC, le botsofali kaofela li susumetsa ts'ebetso ea 'nete ea lefatše.

Lithuto Tsa Litaba Tse Sebetsang

Ho Switching Regulator Stability Taba

Mofetoleli oa 2 MHz oa buck o bonts'itse ts'ebetso e sa tsitsang e nang le oscillation ea motlakase o tsoang leha ho na le moeli o lekaneng o baliloeng. The 22 µF output capacitor e nang le 100 milliohm maximum ESR e hlile e lekanya 15 milliohms, e tlosa ESR zero ho loop ea taolo. Ho kenyelletsa 2.2 ohm series resistor ka ho tsamaisana le 10 µF low-ESR MLCC ho khutlisitse maqhubu a zero ha ho ntse ho boloka ts'ebetso e ntle ea ripple.

Phokotso ea EMI ka ho ntlafatsa sebopeho

Moralo oa lebelo le phahameng oa dijithale o hlotsoe ho etsa tlhahlobo ea mesi ka 8 dB ho 150 MHz leha ho ne ho na le boleng bo lekaneng ba capacitor. Litlhahlobo li bonts'itse 0.1 µF MLCCs e behiloe 15 mm ho tloha ho lithakhisa tsa motlakase tsa IC tse nang le mesaletsa e mesesane e bakang loop inductance e feteletseng. Ho tsamaisa li-capacitor ka har'a limilimithara tse 3 tsa likhoele ho sebelisa 0.5 mm ka bophara ho fokolitse mesi ka 10 dB, ho fihlela tumellano ka ho ntlafatsa sebopeho feela.

fihlela qeto e

Bohlokoa ba ho Nahanela Pele

Litsamaiso tse matla ka ho fetisisa li sebetsana le likokoana-hloko ho tloha sethaleng sa moralo-nako e telele pele bothata bo qala. Litekanyo tsa kapele le netefatso nakong ea ho etsa lipapiso li re thusa khafetsa ho fumana litaba tse amanang le khafetsa tse ka hlahang hamorao.

Tlhophiso Holim'a Khetho ea Karolo

Re boetse re bone hore ho khetha "betere" capacitor ha se hangata ho rarolla mathata a ts'ebetso ka boyona. Ho beoa, ho tsamaisa, sebaka sa loop, le boits'oaro ba khafetsa ba marang-rang a matla kaofela li bohlokoa ka ho lekana.

Ho Fetola Li-Parasitics ho Etsa Liparamente tsa Moralo

Sehlopha sa rona se nka ESR le ESL e le meralo e laolehang ho e-na le litšitiso tse ke keng tsa qojoa. Ka mekhoa e hlophisitsoeng ea moralo le netefatso e nepahetseng, likokoana-hloko tsena li fetoha lintho tse ka lebelloang tse re thusang ho fana ka litsamaiso tsa elektroniki tse sebetsang hantle haholo.