Don bincike da haɓaka canjin wutar lantarki, PCB zane yana da matsayi mai mahimmanci. A bad PCB has poor EMC performance, high output noise, weak anti-interference ability, and even basic functions are defective.

Ya ɗan bambanta da sauran PCBS na kayan masarufi, ikon canza PCBS yana da wasu halayen nasu. Wannan labarin zai yi magana a taƙaice game da wasu mahimman ƙa’idodin wayoyin PCB don sauya wutan lantarki dangane da ƙwarewar injiniya.

1, tazara

Dole ne a yi la’akari da tazarar layi don samfuran high voltage. Tazarar da za ta iya biyan buƙatun ƙa’idodin aminci masu dacewa daidai ne mafi kyau, amma sau da yawa don samfuran da ba sa buƙatar takaddun shaida, ko kuma ba za su iya cika takaddun ba, ƙwarewar ta ƙayyade tazarar. Wanne faɗin tazara ya dace? Dole ne a yi la’akari da samarwa ko don tabbatar da tsabtace farfajiyar ƙasa, danshi na muhalli, sauran gurɓataccen yanayi na jiran yanayi yadda.

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. Aka gyara a gefen allon

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 Kwatanta damuwa a kan na’urar lokacin da farantin ya kasu kashi biyu

Ana iya ganin cewa yakamata na’urar ta kasance nesa da layi ɗaya zuwa gefen mai rarrabawa, in ba haka ba ɓangaren na iya lalacewa saboda rabewar PCB.

3. Loop area

Whether input or output, power loop or signal loop, should be as small as possible. Ƙarfin wutar yana fitar da filin electromagnetic, wanda zai haifar da halayen EMI mara kyau ko babban amo na fitarwa; At the same time, if received by the control ring, it is likely to cause an exception.

A gefe guda, idan madaidaicin madaidaicin wutar lantarki ya fi girma, kwatankwacin saɓin parasitic shima zai ƙaru, wanda na iya haɓaka ƙarar amo.

4. Waya mai mahimmanci

Saboda tasirin DI/DT, dole ne a rage shigarwar a kumburin kumburi, in ba haka ba za a samar da filin wutar lantarki mai ƙarfi. Idan ana son rage inductance, a zahiri so a rage tsawon wayoyi, ƙara girman aikin ƙarami ne.

5. igiyoyin sigina

Don duk ɓangaren sarrafawa, ya kamata a ba da fifiko ga wayoyi daga sashin wutar lantarki. Idan biyun suna kusa da juna saboda wasu ƙuntatawa, layin sarrafawa da layin wutar bai kamata su zama a layi ɗaya ba, in ba haka ba yana iya haifar da aiki mara kyau na samar da wutar lantarki, girgiza.

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. FIG. 2 yana nuna madaidaiciya kuma ba daidai ba hanyoyin jigilar layin siginar tsakanin A da B.

Hoto 2 Sahihi da kuskure hanyoyin kebul na siginar waya.

Tabbas, layin sigina yakamata ya rage haɗin ta ramuka!

6, irin

Wani lokaci sanya jan ƙarfe gaba ɗaya ba dole bane kuma yakamata a guji shi. Idan jan ƙarfe ya yi yawa kuma ƙarfinsa ya bambanta, yana iya yin aiki azaman eriya, yana haskaka raƙuman lantarki a kusa da shi. A gefe guda, yana da sauƙin ɗaukar amo.

Gabaɗaya, ana ba da izinin sanya jan ƙarfe a kan madaidaiciyar nodes, kamar kumburin “ƙasa” a ƙarshen fitarwa, wanda zai iya haɓaka ƙarfin fitarwa yadda yakamata da tace wasu siginar amo.

7, taswira,

Don kewaya, ana iya sanya tagulla a gefe ɗaya na PCB, wanda ke yin taswira ta atomatik zuwa wayoyin a gefe guda na PCB don rage ƙarancin kewaya. Kamar dai an haɗa saitin cikas tare da ƙimomin impedance daban -daban a layi ɗaya, kuma na yanzu zai zaɓi hanyar ta atomatik tare da mafi ƙarancin ƙarancin wucewa.

A zahiri za ku iya yin amfani da sashin sarrafa da’irar a gefe ɗaya, da sanya jan ƙarfe a kumburin “ƙasa” a ɗayan gefen, kuma haɗa ɓangarorin biyu ta rami.

8. Diode mai gyara fitarwa

Idan diode rectifier diode yana kusa da fitarwa, bai kamata a sanya shi daidai da abin fitarwa ba. In ba haka ba, filin electromagnetic da aka samar a diode zai shiga cikin madaurin da aka samar ta hanyar samar da wutar lantarki da lodin waje, ta yadda ƙarar fitowar da aka auna ta ƙaru.

FIG. 3 Sanya diodes daidai da kuskure

9, waya ta kasa,

Wajibi na igiyoyin ƙasa dole ne su mai da hankali sosai. In ba haka ba, EMS, EMI da sauran ayyukan na iya tabarbarewa. Don sauya wutar lantarki ta PCB “ƙasa”, aƙalla maki biyu masu zuwa: (1) ƙasa mai ƙarfi da siginar ƙasa, yakamata ya zama haɗin ma’ana ɗaya; (2) Kada a sami madauki na ƙasa.

10. Y capacitance

Shigarwa da fitarwa galibi ana haɗa su da Y capacitor, wani lokacin saboda wasu dalilai, maiyuwa ba zai iya rataya akan ƙasa mai shigar da ƙarfin shigarwa ba, tuna a wannan lokacin, dole ne a haɗa shi da madaidaicin kumburi, kamar babban tashar wutar lantarki.

11, wasu

Lokacin zayyana PCB na ainihin samar da wutar lantarki, akwai wasu wasu batutuwa da za a yi la’akari da su, kamar “varistor yakamata ya kasance kusa da kewaye mai kariya”, “shigar da yanayin gama gari don haɓaka hakoran fitarwa”, “guntun wutar lantarki ta VCC ya kamata. kara karfin capacitor ”da sauransu. Bugu da ƙari, yakamata a yi la’akari da buƙatar magani na musamman, kamar allurar jan ƙarfe, garkuwa, da sauransu, a matakin ƙirar PCB.

Wani lokaci sau da yawa yakan haɗu da wasu ƙa’idodi masu rikitarwa da juna, don saduwa da ɗayansu ba zai iya saduwa da ɗayan ba, wannan shine buƙatar injiniyoyi don amfani da ƙwarewar data kasance, gwargwadon ainihin buƙatun aikin, ƙayyade mafi dacewa da wayoyi!