Ke kamaʻilio nei no ka pilikia paʻakikī o ka lako mana kuapo, 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: Hana uila, kaʻina hana, nā pono palekana, ka hopena o EMC, a pēlā aku. Ma waena o nā mea e noʻonoʻo ai, ʻo ka uila ka mea nui loa, akā ʻo ka EMC ka mea paʻakikī e hoʻomaopopo, a ʻo ka ʻōmole o nā papahana he nui i EMC. ʻO ka aʻe mai nā ʻōkuhi 22 e kaʻana like i ka papa PCB a me EMC.

1, hiki i ke kaapuni makua ke leisurely PCB hoʻolālā EMI kaapuni

Hiki ke noʻonoʻo ʻia ka hopena o ke kaapuni ma luna ma EMC, eia nā kānana hoʻokomo; Lightning-proof pressure sensitivity; Ke kūʻē R102 e pale aku ai i kēia manawa (me ka relay e hōʻemi ai i ka nalo ʻana); Key error mode X capacitance and Y capacitance with inductor filtering; Aia nā fuse e pili ana i ka papa palekana; He mea nui kēlā me kēia pono pono, a e mahalo nui ʻia ka hana a me ka hana o kēlā me kēia hāmeʻa. 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. Kaapuni a me ka EMC: (ʻo ka topology kumu nui flyback i ʻike nui ʻia, e ʻike i nā ʻāpana nui o ke kaapuni i loaʻa iā EMC mīkini)

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. Akā ke hoʻololi nei kahi loli uila i kahi kahua magnetic e loli nei, a hiki i kahi kahua magnetic hoʻololi ke hana i kahi kahua uila (ʻo ka ʻoiaʻiʻo, ʻo kēia ka hoʻohālikelike Maxwell kaulana a ke hoʻohana nei wau i ka ʻōlelo maʻamau), a hiki i kahi pā uila e loli ke hana i kahi magnet. kahua. No laila e nānā pono i nā wahi kahi ma / ma waho o nā mokuʻāina, ʻo ia kekahi o nā kumuwaiwai o ka EMC, a ʻo kēia kekahi o nā kumuwaiwai o ka 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! ʻO nā lou aʻe ʻelua he mau puka lou omo a hoʻoponopono i nā puka lou, maopopo mua ma mua, a laila kamaʻilio.

3. ʻO ka hui ma waena o ka hoʻolālā PCB a me 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. ʻO ka ʻāpana o ka hoʻolālā, ʻaʻole maikaʻi ka papa hoʻolālā radiator e hoʻopili i ka papa o ka mana pale.

4. Inā kokoke loa ka ʻāpana ʻāpiki i ke kumu interferensi, e like me ka pōʻaiapuni EMI a me ka paipu kuapo, e alakaʻi ʻia ia i EMC maikaʻi ʻole, a koi ʻia kahi wahi kaʻawale.

5. Ka hoʻopili ʻana o ka loop loop absorption RC.

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

I’m going to talk about this, and I’m going to talk about it more, but I’m going to give you a lead.

Here’s a quick example:

E like me ka mea i hōʻike ʻia i ka pahu kiko kiko i ke kiʻi ma luna, ua hoʻopili ʻia ka uila X capacitor pin. Hiki iā ʻoe ke aʻo pehea e hana ai i ka uea pin capacitor i waho (e hoʻohana ana i ka uʻi o kēia wā). I kēia ala, hiki i ka hopena kānana o X capacitor ke hōʻea i ka mokuʻāina ʻoi loa.

4. Hoʻomākaukau no ka hoʻolālā PCB: (inā mākaukau piha ʻoe, hiki i ka hoʻolālā ke hoʻonohonoho i kēlā me kēia manawa e hōʻalo i ka hoʻolālā hoʻohuli a hoʻomaka hou)

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. Ke koho ʻana i ke ala maʻamau: koho panela pālua pālua, a i ʻole papa multi-layer, e like me ke kiʻikuhi a me ka nui o ka papa, ke kumukūʻai a me nā loiloi piha.

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. ʻO ka mamao o ka pad fuse hoʻokomo ʻoi aku ka nui ma mua o 3.0mm e like me ka mea e koi ʻia e nā kānāwai palekana, a ʻo 3.5mm ka papa maoli (e ʻōlelo maʻalahi wale ana, ʻo 3.5mm ka mamao o ka fuse ma mua a 3.0mm ma hope).

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. Pono nā lula palekana no ka pae mua i 6.4mm (hakahaka uila), a ʻo 7.6mm ka mamao o ka creepage. (E hoʻomaopopo e pili ana kēia i ka volta hoʻokomo maoli, pono e nānā i ka papa no ka helu pono ʻana, ka ʻikepili i hāʻawi ʻia no ke kuhikuhi wale nō, ma lalo o ke kūlana maoli.

5. Cold ground and hot ground are clearly marked for the first stage; L, N mark, INPUT AC INPUT mark, fuse mark mark a pēlā aku e pono e māka maopopo.

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. I nā kānāwai palekana, e hoʻomaopopo i nā ʻano hoʻopulapula o ka wahi kokoke me ka papa PCB, kahi kahi insulate maʻamau, kahi wahi i hoʻonui ʻia ka insulation, ʻaʻole like ka mamao insulation maʻamau. ʻOi aku ka maikaʻi e nānā i nā kūlana, a hiki ke helu i ka mamao uila, ka mamao o ka creepage.

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. Ka pilina ma waena o ka capacitance Y a me ke kahe o ka wā a me ke au e hoʻopili ai.

A pēlā aku, e wehewehe kikoʻī ʻo ia i ka haʻalele ʻana i kahi mamao, pehea e hana ai i nā koi palekana.

6, hoʻolālā PCB o ka hoʻonohonoho lako mana

1. E ana mua i ka nui o PCB a me ka helu o nā ʻāpana, i mea e loaʻa ai kahi mānoanoa maikaʻi, a i ʻole ka manoanoa, eʻinoʻino ka sparse.

2. Hoʻololi i ke kaapuni, lawe i nā hāmeʻa ma ke ʻano he kikowaena, a hoʻokau i nā hāmeʻa mua.

3. Kū a kūpaʻa paha ka mea i kahi hoʻonohonoho anti-positioning, nani kekahi, ʻo kahi mea maʻalahi plug-in ka hana, hiki i nā kūlana kūikawā ke noʻonoʻo i ke kuli.

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

5. E hoʻemi i ka wahi o ka loop i ka manawa hiki i ka hoʻonohonoho. E wehewehe ākea ʻia nā puka lou ʻehā ma hope.

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

ʻO ka mea aʻe ka PCB puʻupaʻa mua aʻu i huki ai, i mau makahiki i hala aku nei, paʻakikī e hoʻopau, aia paha kahi pilikia liʻiliʻi i waenakonu, akā pono ka hoʻolālā maʻamau i ke aʻo ʻana:

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. Hoʻopaʻa ʻia nā kikowaena hoʻokomo a puka a hiki ʻole ke neʻe. He huinahā ka papa.

Eia ka hoʻonohonoho mai lalo a luna, mai ka hema a me ka ʻākau, a kaukaʻi ʻia ka wela ma luna o ka pūpū.

2.EMI kaapuni ka mōakāka o ke kahe o ke kahe, kahi mea nui ia, inā ʻaʻole nani a maikaʻi ʻole ia no 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. Hele maikaʻi ʻole ka papa luna o ka mana kiʻekiʻe, a maikaʻi ka pae o lalo.

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. ʻO ka mahalo i nā laʻana PCB

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! Behind will also be for this board to explain learning, we first enjoy.

8. Ka hoʻomaopopo ʻana i nā puka lou ʻehā o ka hoʻolālā PCB: (ʻo ke koi kumu o ka hoʻonohonoho PCB kahi wahi liʻiliʻi o nā puka lou ʻehā)

Hoʻohui ʻia, ʻo ka omo omo (omo RCD, omo RC o ka paipu MOS a me RC omo o ka paipu pololei) he mea nui pū kekahi, a ʻo ia hoʻi ka loop e hoʻoulu ai i ka radiation radiation alapine. Inā he mau nīnau kāu e pili ana i ke kiʻi ma luna, ʻoluʻolu ʻoe e kūkākūkā me lākou. ʻAʻole mākou makaʻu i kekahi nīnau.

9. PCB hoʻolālā hoʻolālā wela (lana kiko hiki) a me ka uea lepo:

Nā mea e pono ai ka nānā ʻana:

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. ʻO ka loop loop i hana ʻia e nā wahi wela, he liʻiliʻi ia a pōkole ke kaula uila, ʻaʻole lawa ka mānoanoa o ke kaula uila, akā inā lawa ka ʻikena.

3. Pono e hoʻokumu i ke kaula honua i hoʻokahi kiko. ʻO ka papa mana nui a me ka honua hōʻailona e hoʻokaʻawale, hele ʻokoʻa ka laʻana.

4. Pono e hoʻopili ka honua o ka radiator i ka honua mana nui.