Kutaura nezve dambudziko rakaoma rekushandura magetsi, PCB cloth plate problems is not very difficult, but if want to cloth up a refined PCB must be one of the difficulties in switching power supply (PCB design is not good, may cause no matter how to debug parameter debugging cloth out of the situation, so not scaremongering) when reason was the PCB board consideration or a lot of, such as: Kuita kwemagetsi, nzira yekuita, kuchengetedzwa zvinodiwa, EMC kukanganisa, nezvimwe; Pakati pezvinhu zvinofanirwa kutariswa, magetsi ndiwo akanyanya kukosha, asi EMC ndiyo yakanyanya kunzwisisika, uye ganda remapurojekiti mazhinji riri muEMC. Aya anotevera kubva kunongedzo makumi maviri neshanu ekugovana pcb board uye EMC.

1, dunhu rakakura rinogona kuve leisurely pcb dhizaini EMI redunhu

Iko kukanganisa kwedunhu riri pamusoro paEMC kunogona kufungidzirwa, mafirita ekuisa ari pano; Lightning-proof pressure sensitivity; Kuramba R102 kudzivirira kuvhunduka kwazvino (iine relay yekudzora kurasikirwa); Key error mode X capacitance and Y capacitance with inductor filtering; Pane mafyuzi anokanganisa bhodhi rekuchengetedza; Chimwe nechimwe chezvigadzirwa izvi chakakosha, uye mashandiro uye chiito cheichi chigadzirwa chinofanira kukosheswa. The EMC severity level should be considered when designing the circuit, such as the number of filters to be set, the number and location of the y-capacitor quantity. The choice of pressure-sensitive size and quantity is closely related to our requirements for EMC. Welcome to discuss the seemingly simple EMI circuit that actually contains profound truths for each component.

2. Dunhu uye EMC: (iyo inozivikanwa kwazvo kubhururuka kumusoro topology, ona kuti ndeapi matunhu edunhu ane EMC michina)

The circled parts in the circuit in the figure above are very important for EMC (note that the green part is not), such as radiation. It is known that electromagnetic field radiation is spatial, but the basic principle is the change of magnetic flux, which involves the effective cross-sectional area of magnetic field, namely the corresponding loop in the circuit. The electric current can produce a magnetic field, which is stable and cannot be converted into an electric field. Asi shanduko yemagetsi inoburitsa inoshanduka yemagineti, uye shanduko yemagineti inogona kuburitsa magetsi (muchokwadi, iyi ndiyo inozivikanwa Maxwell equation uye ndiri kushandisa mutauro wakajeka), uye shanduko yemagetsi munda inogona zvakare kuburitsa magnetic munda. Saka ita shuwa kuti iwe unoteerera kune nzvimbo uko kune on / off states, ndicho chimwe chezvinyorwa zveEMC, uye ichi ndicho chimwe cheanobva EMC. For example, the dotted line loop in the circuit is the opening and closing loop of the switch tube. Not only the switching speed can be adjusted during the design of the circuit, but also the area of the wiring loop of the layout board has an important influence on EMC! Iwo mamwe malupu maviri ekumwa uye ekugadzirisa zvishwe, tanga unzwisise pamberi, wozotaura!

3. Sangano pakati pePCB dhizaini uye EMC

1.PCB loop has a very important influence on EMC, such as flyback main power loop. If it is too large, the radiation will be poor.

2. Filter wiring effect, filter is used to filter out interference, but if PCB wiring is not good, filter may lose the effect it should have.

3. Chikamu chechimiro, iyo radiator dhizaini yekumisikidza haina kunaka inokanganisa kugadzika kweshanduro yakadzivirirwa;

4.Kana iyo inonzwisisika chikamu chiri padyo padyo nechavhiringidza sosi, senge EMI dunhu uye chinja chubhu, zvinongotungamira kune varombo EMC, uye nzvimbo yakajeka yekuzvitsaura inodiwa.

5. Wiring yeRC inotora chiuno.

6.Y capacitor grounding and wiring, and the position of Y capacitor is also critical!

Ini ndichataura nezve izvi, uye ndichataura nezvazvo zvakanyanya, asi ndiri kuzokutungamira.

Here’s a quick example:

Sezvinoratidzwa mubhokisi rakazara mumufananidzo uri pamusoro, X capacitor pini wiring yakaiswa mukati. Iwe unogona kudzidza maitiro ekugadzira iyo capacitor pini wiring yekunze (uchishandisa iyo svina yazvino wiring). Nenzira iyi, iyo yekusefa mhedzisiro yeX capacitor inogona kusvika kune yakanyanya mamiriro.

4. Kugadzirira kwePCB dhizaini: (kana iwe wakanyatsogadzirira, dhizaini inogona kudzikama nhanho nhanho kudzivirira dhizaini kupidigura uye kutanga zvakare)

There are roughly the following aspects, are their own design process to consider, all the content has nothing to do with other tutorials, are just their own experience summary.

1. Appearance structure size, including positioning hole, air channel flow direction, input and output socket, need to match with the customer system, also need to communicate with the customer assembly problems, height limit and so on.

2. Safety certification, products do what kind of certification, where do the basic insulation creepage distance to leave enough, where do strengthen the insulation to leave enough distance or slot.

3. Packaging design: there is no special period, such as preparation for customized packaging.

4. Maitiro nzira kusarudzwa: imwechete pani mbiri mapaneru kusarudzwa, kana akawanda-masenduru bhodhi, zvinoenderana neyechirongwa dhizaini uye bhodhi saizi, mutengo uye kumwe kuongorora kwakazara.

5. Other special requirements of customers.

The structure and process will be relatively more flexible, safety regulations or relatively fixed part, what certification to do, what safety standards, of course, there are some safety regulations are common in many standards, but there are also some special products such as medical treatment will be more stringent.

For the new entry engineer friends are not dazzled;

Next list some general products general, the following is summarized for IEC60065 specific cloth requirements, for safety needs to keep in mind, encounter specific products will be targeted processing:

1. Daro rekupinza fiyuzi pad rakakura kupfuura 3.0mm sekudikanwa nemitemo yekuchengetedza, uye ndiro chaiyo 3.5mm (kutaura chete, chinhambwe chefuse iri 3.5mm pamberi uye 3.0mm mushure).

2. Before and after the rectifier bridge, the safety requirements are 2.0MM, and the plate layout is 2.5MM.

3. After rectification, safety regulations generally do not require, but the distance between high and low voltage is left according to the actual voltage, and 400V high voltage is left above 2.0mm.

4. Iyo yekuchengetedza mirau yedanho rekutanga inoda 6.4mm (magetsi mukaha), uye nzvimbo yekukwira inofanirwa kunge iri 7.6mm. (Cherekedza kuti izvi zvinoenderana nemagetsi ekuisa chaiwo, inoda kureva tafura yekuverenga chaiyo, iyo data yakapihwa referenzi chete, zvichitungamirwa nemamiriro ezvinhu chaiwo)

5. Cold ground and hot ground are clearly marked for the first stage; L, N mucherechedzo, INPUT AC INPUT mucherechedzo, chiratidzo cheyuziyasi uye zvichingodaro zvinofanirwa kuve zvakanyatso nyorwa;

It is reiterated that the actual safety distance is related to the actual input voltage and the working environment, so it is necessary to refer to the table for specific calculation. The data provided is for reference only and shall prevail in the actual situation.

5. Consider other factors for PCB design safety

1. Understand what certification their products do and what product categories they belong to. For example, medical treatment, communication, electricity, TV and so on are different, but there are also many similarities.

2. Mumitemo yekuchengetedza, nzwisisa maficha ekuputira enzvimbo yepedyo nePCBboard, inova nzvimbo yekudzivirira kwekutanga, inzvimbo ipi yakasimbiswa kuputira, akasiyana mwero wekusimbisa daro haana kufanana. Izvo zvakanaka kuti utarise zviyero, uye inogona kuverenga kureba kwemagetsi, kureba kwenzvimbo.

3. Focus on the safety devices of the product, such as the relationship between the magnetism of the transformer and the original side;

4. Radiator and surrounding distance problem, radiator insulation is not the same as the ground is not the same, the ground is cold, hot insulation is the same cloth.

5. Special attention should be paid to the distance of insurance, requiring the strictest place. The distance between front and rear of the fuse is consistent.

6. Hukama pakati peY capacitance uye leakage yazvino uye yekubata yazvino.

Uye zvichingodaro, ichatsanangura zvakadzama maitiro ekusiya chinhambwe, maitiro ekuchengetedza zvinodiwa.

6, pcb dhizaini yekugovera magetsi dhizaini

1. Chekutanga kuyera saizi pcb uye huwandu hwezvinhu, kuti uwane huwandu hwakanaka, kana dense, hushoma huchave hwakaipa.

2. Modularize dunhu, tora ekumusoro madhijitari sepakati, woisa makiyi ekutanga.

3. Chishandiso chakamira kana chakamira chinopesana nekumira, imwe yakanaka, imwe iri nyore plug-in oparesheni, mamiriro akasarudzika anogona kufunga kutenderera.

4. Take cabling into consideration and arrange the layout in the most reasonable position for subsequent cabling.

5. Deredza nzvimbo yekutenderera zvakanyanya sezvinobvira panguva yekugadzika. Zvishwe zvina zvichatsanangurwa zvakadzama gare gare.

Do the above points, of course, flexible use, more reasonable layout will be born soon.

Inotevera ndiyo yekutanga mhandara PCB yandakadhonza, makore mazhinji apfuura, zvaive zvakaoma kupedzisa, panogona kunge paine dambudziko diki pakati, asi chimiro chakazara chakakodzera kudzidza:

In this figure, the power density is still relatively high. The control part of LLC, the auxiliary source part and the BUCK circuit driver (high-power multi-channel output) part are on the small board, which is not taken out. Let’s take a look at the layout characteristics of the main power:

1. Input uye zvabuda zviteshi zvakagadziriswa uye hazvigone kufambiswa. Iyo bhodhi yakatenderera.

Pano marongero anobva pasi kuzasi, kubva kuruboshwe kuenda kurudyi, uye kupisa kupisa kunobva pane iyo shell.

2.EMI redunhu ichiri yakajeka kuyerera mafambiro, ayo akakosha kwazvo, zvikasadaro haina kunaka uye yakaipa kune EMC.

3. The position of large capacitor should consider PFC loop and LLC main power loop as far as possible;

4. The current of the side side is relatively large. In order to run the current and dissipate the heat of the rectifier tube, this layout is adopted. Iyo yepamusoro dhayeti yesimba rakakwira kazhinji inoenda isina kunaka, uye yepasi dura inoenda yakanaka.

Each board has its own characteristics, of course, also has its own difficulties, how to reasonably solve the key, we can understand the layout of reasonable selection of meaning?

7. Kukoshesa mienzaniso yePCB

I think it is a good place to do it. Of course, there will always be defects, which can also be pointed out. It is not easy for a single panel to be so compact, so you can use this board to learn and discuss! Kuseri kuchavewo kwebhodhi iri kutsanangura kudzidza, isu tinotanga kufarira.

8. Kunzwisisa kwemakona mana ePBB dhizaini: (iyo yakakosha kudikanwa kwePBB dhizaini inzvimbo diki yezvishongo zvina)

Uye zvakare, iyo yekumwa chiuno (RCD yekumwa, RC yekumwa kweMOS chubhu uye RC yekumwa yeanodzora chubhu) zvakare yakakosha, iyo zvakare iri chiuno chinogadzira yakakwira frequency radiation. Kana iwe uine chero mibvunzo nezve iri pamusoro nhamba, unogamuchirwa kuti ukurukure nezvayo. Hatityi chero mibvunzo.

9. pcb dhizaini inopisa nzvimbo (inoyerera inogona nzvimbo) uye pasi waya:

Zvinhu zvinoda kutarisirwa

1. Pay special attention to hot spots (high-frequency switching points), which are high-frequency radiation points. Cable layout has a great impact on EMC.

2. Chiuno chakagadzirwa nenzvimbo dzinopisa idiki uye wiring ipfupi, uye iyo wiring haina kuenzana sezvinobvira, asi sekureba kwazvino kwaringana.

3. Iyo tambo yepasi inofanira kuiswa pasi pane imwechete poindi. Main simba pasi uye chiratidzo chevhu chakaparadzaniswa, sampling pasi inoenda zvakasiyana.

4. Ivhu redhiyeta rinoda kuve rakabatana nenzvimbo huru yemagetsi.