Awọn idii IC gbarale PCB fun pipinka ooru. In general, PCB is the main cooling method for high power semiconductor devices. A good PCB heat dissipation design has a great impact, it can make the system run well, but also can bury the hidden danger of thermal accidents. Išọra abojuto ti ipilẹ PCB, eto igbimọ, ati oke ẹrọ le ṣe iranlọwọ lati mu ilọsiwaju itusilẹ ooru fun alabọde-ati awọn ohun elo agbara giga.

Awọn aṣelọpọ semikondokito ni iṣoro ṣiṣakoso awọn eto ti o lo awọn ẹrọ wọn. Bibẹẹkọ, eto kan pẹlu IC ti o fi sii jẹ pataki si iṣẹ ẹrọ lapapọ. Fun awọn ẹrọ IC aṣa, oluṣeto eto ni igbagbogbo ṣiṣẹ ni pẹkipẹki pẹlu olupese lati rii daju pe eto naa pade ọpọlọpọ awọn ibeere ifasita ooru ti awọn ẹrọ agbara giga. Ifowosowopo kutukutu yii ṣe idaniloju pe IC pade itanna ati awọn ajohunše iṣẹ, lakoko ṣiṣe idaniloju iṣẹ ṣiṣe to dara laarin eto itutu alabara. Many large semiconductor companies sell devices as standard components, and there is no contact between the manufacturer and the end application. Ni ọran yii, a le lo diẹ ninu awọn itọsọna gbogbogbo lati ṣe iranlọwọ lati ṣaṣeyọri ojutu itusilẹ igbona palolo ti o dara julọ fun IC ati eto.

Bii o ṣe ṣe apẹrẹ pipin ooru fun PCB

Iru package semikondokito ti o wọpọ jẹ paadi igboro tabi package PowerPADTM. In these packages, the chip is mounted on a metal plate called a chip pad. Iru paadi chiprún yii ṣe atilẹyin chiprún ninu ilana sisẹ chiprún, ati pe o tun jẹ ọna igbona ti o dara fun itusilẹ igbona ẹrọ. When the packaged bare pad is welded to the PCB, heat is quickly exited from the package and into the PCB. The heat is then dissipated through the PCB layers into the surrounding air. Awọn idii paadi igboro ni igbagbogbo gbe nipa 80% ti ooru sinu PCB nipasẹ isalẹ ti package. 20% to ku ti ooru ti jade nipasẹ awọn okun ẹrọ ati ọpọlọpọ awọn ẹgbẹ ti package. Kere ju 1% ti ooru yọ kuro nipasẹ oke ti package. Ninu ọran ti awọn idii paadi-paadi wọnyi, apẹrẹ pipin igbona PCB ti o dara jẹ pataki lati rii daju iṣẹ ẹrọ kan.

Apa akọkọ ti apẹrẹ PCB ti o mu iṣẹ ṣiṣe igbona dara jẹ ipilẹ ẹrọ PCB. Nigbakugba ti o ba ṣeeṣe, awọn paati agbara giga lori PCB yẹ ki o ya sọtọ si ara wọn. Aye aaye ti ara laarin awọn paati agbara giga mu iwọn agbegbe PCB pọ si ni ayika paati agbara kọọkan, eyiti o ṣe iranlọwọ lati ṣaṣeyọri gbigbe ooru to dara julọ. Care should be taken to separate temperature sensitive components from high power components on the PCB. Nibikibi ti o ba ṣee ṣe, awọn paati agbara giga yẹ ki o wa ni aaye lati awọn igun ti PCB. Ipo PCB agbedemeji diẹ sii mu iwọn agbegbe igbimọ pọ si ni ayika awọn paati agbara giga, nitorinaa ṣe iranlọwọ lati tuka ooru. Awọn ẹrọ semikondokito aami meji ni a fihan: awọn paati A ati B. Paati A, ti o wa ni igun PCB, ni iwọn otutu idapọmọra A chiprún 5% ga ju paati B, eyiti o wa ni ipo diẹ sii ni aarin. Gbigbọn ooru ni igun paati A jẹ opin nipasẹ agbegbe nronu kekere ni ayika paati ti a lo fun itusilẹ ooru.

Apa keji ni eto ti PCB, eyiti o ni ipa ipinnu pupọ julọ lori iṣẹ igbona ti apẹrẹ PCB. Gẹgẹbi ofin gbogbogbo, diẹ sii Ejò ti PCB ni, iṣẹ ṣiṣe igbona ti o ga julọ ti awọn paati eto. Ipo itusilẹ ooru ti o peye fun awọn ẹrọ semikondokito ni pe a ti gbe chiprún sori pẹpẹ nla ti idẹ-tutu tutu. Eyi ko wulo fun ọpọlọpọ awọn ohun elo, nitorinaa a ni lati ṣe awọn ayipada miiran si PCB lati mu itusilẹ ooru wa. For most applications today, the total volume of the system is shrinking, adversely affecting heat dissipation performance. Larger PCBS have more surface area that can be used for heat transfer, but also have more flexibility to leave enough space between high-power components.

Nigbakugba ti o ba ṣeeṣe, mu nọmba pọ ati sisanra ti awọn fẹlẹfẹlẹ idẹ PCB. Iwọn ti bàbà ilẹ ni gbogbogbo tobi, eyiti o jẹ ọna igbona ti o tayọ fun gbogbo itasi igbona PCB. The arrangement of the wiring of the layers also increases the total specific gravity of copper used for heat conduction. Bibẹẹkọ, wiwakọ yii jẹ igbagbogbo ti a ti ya sọtọ ni itanna, diwọn lilo rẹ bi ẹrọ igbona ooru ti o pọju. Ilẹ ẹrọ yẹ ki o wa ni wiwọn bi ina mọnamọna bi o ti ṣee ṣe si ọpọlọpọ awọn fẹlẹfẹlẹ ilẹ bi o ti ṣee ṣe lati ṣe iranlọwọ mu iṣipopada ooru pọ si. Awọn ihò itutu igbona ninu PCB ni isalẹ ẹrọ semikondokito ṣe iranlọwọ ooru lati wọ awọn fẹlẹfẹlẹ ifibọ ti PCB ati gbigbe si ẹhin igbimọ.

Awọn ipele oke ati isalẹ ti PCB jẹ “awọn ipo akọkọ” fun ilọsiwaju itutu agbaiye. Lilo awọn okun to gbooro ati lilọ kuro ni awọn ẹrọ agbara giga le pese ọna igbona fun itusilẹ ooru. Igbimọ adaṣe igbona pataki jẹ ọna ti o tayọ fun itusilẹ igbona PCB. Awo adaṣe igbona naa wa ni oke tabi ẹhin PCB ati pe o ti sopọ ni igbona si ẹrọ nipasẹ boya asopọ bàbà taara tabi iho nipasẹ iho. Ninu ọran ti iṣakojọpọ inline (nikan pẹlu awọn itọsọna ni ẹgbẹ mejeeji ti package), awo adaṣe igbona le wa ni oke PCB, ti a ṣe apẹrẹ bi “egungun aja” (aarin jẹ dín bi package, awọn idẹ kuro lati package ni agbegbe nla, kekere ni aarin ati nla ni awọn opin mejeeji). Ninu ọran ti package ẹgbẹ-mẹrin (pẹlu awọn itọsọna ni gbogbo awọn ẹgbẹ mẹrin), awo adaṣe igbona gbọdọ wa ni ẹhin PCB tabi inu PCB.

Alekun iwọn ti awo adaṣe ooru jẹ ọna ti o tayọ lati mu iṣẹ ṣiṣe igbona ti awọn idii PowerPAD pọ si. Different size of heat conduction plate has great influence on thermal performance. Iwe data ọja tabular nigbagbogbo ṣe atokọ awọn iwọn wọnyi. Ṣugbọn titọkasi ipa ti Ejò ti a ṣafikun lori PCBS aṣa jẹ nira. With online calculators, users can select a device and change the size of the copper pad to estimate its effect on the thermal performance of a non-JEDEC PCB. Awọn irinṣẹ iṣiro wọnyi ṣe afihan iye eyiti apẹrẹ PCB ṣe ni ipa lori iṣẹ itusilẹ ooru. For four-side packages, where the area of the top pad is just less than the bare pad area of the device, embedding or back layer is the first method to achieve better cooling. Fun awọn idii ni ila meji, a le lo aṣa paadi “egungun aja” lati tuka ooru.

Lakotan, awọn eto pẹlu PCBS nla tun le ṣee lo fun itutu agbaiye. The screws used to mount the PCB can also provide effective thermal access to the base of the system when connected to the thermal plate and ground layer. Ṣiyesi ibalopọ gbona ati idiyele, nọmba awọn skru yẹ ki o pọ si si aaye ti awọn ipadabọ idinku. Alagbara PCB irin naa ni agbegbe itutu agbaiye diẹ sii lẹhin ti o ti sopọ si awo igbona naa. Fun diẹ ninu awọn ohun elo nibiti ile PCB ni ikarahun kan, ohun elo alemo TYPE B solder ni iṣẹ ṣiṣe igbona ti o ga julọ ju ikarahun tutu tutu. Awọn solusan itutu, gẹgẹbi awọn onijakidijagan ati awọn imu, ni a tun lo fun itutu eto, ṣugbọn wọn nigbagbogbo nilo aaye diẹ sii tabi nilo awọn iyipada apẹrẹ lati jẹ ki itutu agbaiye dara.

Lati ṣe apẹrẹ eto kan pẹlu iṣẹ ṣiṣe igbona giga, ko to lati yan ẹrọ IC ti o dara ati ojutu pipade. Eto ṣiṣe itutu agbaiye IC da lori PCB ati agbara ti eto itutu lati gba awọn ẹrọ IC laaye lati yara yarayara. Ọna itutu palolo ti a mẹnuba loke le ṣe ilọsiwaju iṣẹ itusilẹ igbona ti eto naa pupọ.