Mo te rangahau me te whanaketanga o te whakawhiti hiko, Hoahoa PCB occupies a very important position. A bad PCB has poor EMC performance, high output noise, weak anti-interference ability, and even basic functions are defective.

He rereke ke atu i etahi atu PCBS taputapu, PCBS whakawhiti mana etahi ahuatanga o raatau. Ka korero poto tenei tuhinga mo etahi o nga kaupapa matua o te waea PCB mo te whakawhiti i te hiko i runga i te wheako hangarau.

1, spacing

Me whakaarohia te mokowhiti raina mo nga hua ngaohiko teitei. Ko te mokowhiti ka tutuki i nga whakaritenga o nga ture haumaru e tika ana te mea tino pai, engari he maha nga wa mo nga hua kaore e hiahiatia he tiwhikete, kaore ranei e tutuki te tiwhikete, ko te waahi ka whakatauhia ma te wheako. He aha te whanui o te mokowhiti e tika ana? Me whai whakaaro ki te whakaputa mena ka whakarite kia ma te papa, he haumuku i te taiao, me etahi atu parahanga e tatari ana mo te ahuatanga ka peheatia.

For the mains input, even if the board surface can be guaranteed clean and sealed, MOS tube drain source electrode close to 600V, less than 1mm is actually more dangerous!

2. Nga waahanga i te pito o te papa

For the patch capacitance or other easily damaged devices at the edge of PCB, the PCB splitter direction must be taken into consideration when placing. The figure shows the comparison of the stress on the devices under various placement methods.

FIG. 1 Comparison of stress on the device when the plate is split

Ka kitea ka matara atu te taputapu me te whakarara ki te tapa o te tohatoha, ki te kore ka pakaru te waahanga na te marara PCB.

3. Loop area

Whether input or output, power loop or signal loop, should be as small as possible. Ko te koropiko hiko ka whakaputa i te waahi hiko, ka arahi i nga ahuatanga EMI kino, i te haruru nui ranei o te whakaputa; At the same time, if received by the control ring, it is likely to cause an exception.

I tetahi atu, mena he nui ake te rohe koropiko hiko, ka piki ano te whakauru pararite rite, ka whakanui ake pea i te haruru o te haruru o te awakeri.

4. waea waea matua

Na te kaha o te DI / DT, me whakaiti te whakauru ki te kōpuku hihiri, ki te kore ka kaha te whakaputa i te papa electromagnetic. Mena kei te hiahia koe ki te whakaheke i te whakauru, me tino hiahia koe ki te whakaheke i te roa o nga waea waea, whakanui ake i te mahi whanui he iti nei.

5. Taura tohu

Mo te waahanga whakahaere katoa, me whakaaro ki nga waea waea mai i te waahanga hiko. Mena he tata nga mea e rua na tetahi atu na te mea he here ke atu, kaua te raina whakahaere me te raina hiko e orite, ki te kore ka arahi pea te mahi rereke o te mana, te ohorere.

In addition, if the control line is very long, a pair of back and forth lines should be close to each other, or the two lines should be placed on the two sides of the PCB facing each other, so as to reduce the loop area and avoid interference by the electromagnetic field of the power part. ATUAHI. E whakaatu ana a 2 i nga tikanga tika me te huringa o te raina tohu i waenga i te A me te B.

Whakaatu 2 He tika me te he nga tohu whakaheke i te taura.

Ae ra, ko te raina tohu me whakaiti i te hononga ma roto i nga rua!

6, parahi

I etahi wa ko te whakatakoto parahi he mea kore noa, engari me karohia. Mena he nui te parahi, me te rereketanga o te ngaohiko, tera pea ka mahi hei antenna, ka whiti nga ngaru hiko i te taha. I tetahi atu, he maama ki te tiki haruru.

Ko te tikanga, ko te whakapanga parahi anake ka whakaaetia ki runga i nga kohinga taatai, penei i te kohinga “whenua” i te mutunga o te putanga, ka taea te whakanui ake i te kaha whakaputa me te taatai ​​i etahi tohu haruru.

7, mahere whenua,

For a circuit, copper can be laid on one side of the PCB, which automatically maps to the wiring on the other side of the PCB to minimize the impedance of the circuit. Ka rite ki te ahua o nga aukati me nga uara rerekee rereke e hono honohono ana, a ko te waa o tenei waa ka kowhiri i te ara me te reanga iti rawa kia rere.

Ka taea e koe te waea i te waahanga whakahaere o te ara iahiko i tetahi taha, ka whakatakoto i te parahi ki runga i te kohinga “whenua” ki tera taha, ka hono i nga taha e rua ki roto i te poka.

8. Waea putu

Mena he tata te diode rectifier whakaputa ki te whakaputanga, kaua e tuu kia rite ki te putanga. Ki te kore, ko te waahi electromagnetic i hangaia i te diode ka uru ki roto i te koropiko i hangaia e te kaha hiko me te kawenga o waho, kia piki ai te tangi o te oro whakaputa.

ATUAHI. 3 Te whakatika tika me te hape o te diode

9, waea whenua,

Me tino tupato nga waea waea o nga taura whenua. Ki te kore, EMS, EMI me etahi atu mahinga ka kino pea. Mo te whakawhiti mana tuku PCB “whenua”, te iti rawa ko nga tohu e rua e whai ake nei: (1) te papa kaha me te papa tohu, kia kotahi te hononga hono; (2) Me kaua he koropiko whenua.

10. Y capacitance

Ko te whakauru me te whakaputa ka hono tonu ki te Y capacitor, i etahi waa mo etahi take, kaore pea e taea te whakairi i runga i te papa whakaurunga whakauru, kia mahara i tenei waa, me hono atu ki te kōpuku tohu, pēnei i te taunga hiko teitei.

11, etahi atu

I a koe e hoahoa ana i te PCB mo te mana mana, tera pea kei etahi atu take hei whakaaro, penei “me tata te varistor ki te ara iahiko i tiakina”, “whakauru aratau noa hei whakanui ake i nga niho tuku”, whakapiki i te capacitor ”me te aha atu. Hei taapiri, ko te hiahia mo te maimoatanga motuhake, penei i te pepa parahi, te whakangungu rakau, me etahi atu, me whakaaro ano hoki i te waahanga hoahoa PCB.

I etahi wa ka tutaki ki te maha o nga matapono e taupatupatu ana ki a ratau ano, kia tutaki tetahi o ratau kaore e tutaki ki tetahi atu, koinei te hiahia o nga kaiwhakangungu ki te whakamahi i nga wheako o naianei, kia rite ki nga hiahia o te kaupapa, whakatauhia nga waea tino tika!