Na imewe TC EMC nke PCB, nchegbu mbụ bụ ntọala oyi akwa; N’ígwé nke bọọdụ ahụ nwere ike ọkọnọ, akwa ala na akwa mgbaama. Na imepụta EMC nke ngwaahịa, ewezuga nhọrọ nke ihe mejupụtara yana imewe sekit, imepụta PCB dị mma bụkwa ihe dị oke mkpa.

The key to the EMC design of PCB is to minimize the backflow area and make the backflow path flow in the direction we designed. Nhazi oyi akwa bụ ntọala PCB, kedu ka esi eme ezigbo ọrụ nke imebe akwa PCB iji mee mmetụta EMC nke PCB kacha mma?

I. Kere echiche nke PCB oyi akwa

The core of PCB laminated EMC planning and design is to reasonably plan signal backflow path to minimize the backflow area of signal from the board mirror layer, so as to eliminate or minimize magnetic flux.

Otu bọọdụ na -enyo enyo

Igwe enyo bụ akwa oyi akwa mkpuchi mkpuchi ọla kọpa (oyi akwa ike, akwa ala) n’akụkụ akụkụ mgbaàmà n’ime PCB. Ọrụ ndị bụ isi bụ ndị a:

(1) Belata mkpọtụ azụ: akwa enyo nwere ike inye ụzọ mgbapụta dị ala maka ịlaghachi azụ nke mgbaama, ọkachasị mgbe enwere nnukwu usoro ugbu a na sistemụ nkesa ike, ọrụ enyo enyo pụtara nke ọma.

(2) Mbelata EMI: ịdị adị nke enyo enyo na -ebelata mpaghara nke mkpọchi mechiri emechi nke mgbaàmà na reflux mebere ma belata EMI;

(3) belata crosstalk: nyere aka ịchịkwa nsogbu crosstalk n’etiti ahịrị nrịba na sekit dijitalụ dị elu, gbanwee ịdị elu nke akara akara site na enyo enyo, ị nwere ike ijikwa crosstalk n’etiti ahịrị mgbaàmà, obere ịdị elu, obere akụkụ ihu;

(4) Njikwa impedance iji gbochie ntụgharị uche.

Nhọrọ nke oyi akwa enyo

(1) Enwere ike iji ma ọkọnọ ike ma ụgbọ elu ala dị ka ụgbọ elu ntụnyere aka, ma nwee mmetụta nchekwa ụfọdụ na wiwi ime;

(2) N’ikwu ya n’ụzọ ọzọ, ụgbọ elu ike nwere nnukwu njiri mara njiri mara, enwere nnukwu ọdịiche dị na ọkwa ntụnyere, yana nnyonye anya ugboro ugboro na ụgbọ elu ike dịtụ ukwuu;

(3) Site n’echiche nke ịgbachitere, a na -etinyere ụgbọ elu ala n’ozuzu ya ma jiri ya mee ihe ntụnyere maka ọkwa nrụtụ aka, na mmetụta nchekwa ya ka mma karịa nke ụgbọ elu ike;

(4) Mgbe ị na -ahọrọ ụgbọ elu nrụtụ aka, ekwesịrị ịhọrọ ụgbọ elu ala, yana ụgbọ elu ike kwesịrị ịhọrọ nke abụọ

Two, magnetic flux cancellation principle

Dika nha Maxwell siri kwuo, a na -ebunye ọkụ eletriki na ndọta niile n’etiti otu ebubo ma ọ bụ ebili mmiri dị iche iche site na mpaghara etiti dị n’etiti ha, ma ọ bụ oghere ma ọ bụ ihe siri ike. N’ime PCB, a na -agbasa mgbasa ahụ mgbe niile na ahịrị nnyefe. Ọ bụrụ na ụzọ rf backflow dị ka ụzọ mgbaama kwekọrọ, mmụba nke na -aga azụ azụ dị n’akụkụ nke ọzọ na ụzọ mgbaama, mgbe ahụ ha na -ebufere ibe ha, a na -enwetakwa mmetụta nke kagbuo mmiri.

Ọdịdị nke kagbuo ndọta ndọta

Ihe kacha mkpa kagbuo flux bụ ịchịkwa ụzọ mgbapụta mgbaama, dị ka egosiri na eserese na -esonụ:

Iwu aka nri na -akọwa mmetụta kagbuo ndọta ndọta

Otu esi eji iwu aka nri ịkọwa mmetụta kagbuo ndọta ndọta mgbe akara mgbaàmà dị n’akụkụ stratum ka akọwara dị ka ndị a:

(1) Mgbe ikuku na -agafe na waya, a ga -ewepụta ndọta gburugburu waya ahụ, iwu aka nri na -ekpebi ntụzịaka ndọta ahụ.

(2) mgbe mmadụ abụọ nọ ibe ha na nke yiri waya, dị ka egosiri na foto dị n’okpuru, otu n’ime ndị na -eduzi ọkụ eletrik ịpụ, nke ọzọ onye na -eduzi ọkụ eletrik ga -asọ, ma ọ bụrụ na ọkụ eletrik na -agafe waya dị ugbu a na akara nloghachi ya ugbu a, mgbe ahụ ụzọ abụọ na -emegide nke ugbu a hà nhata, yabụ na oghere ndọta ha nha, mana ntụzịaka ahụ na -emegide,Ya mere, ha na -akagbu onwe ha.

Ihe atụ imewe osisi ise, isii

Maka ọkwa isii, a na -ahọrọ atụmatụ 3

Nyocha:

(1) Ka akwa mgbama dị n’akụkụ ụgbọ elu reflow, na S1, S2 na S3 dị n’akụkụ ụgbọ elu ala, a na -enweta nsonaazụ kagbuo ndọta kacha mma. Yabụ, S2 bụ okirikiri ụzọ ntụgharị ka mma, S3 na S1 sochiri.

(2) Ụgbọ elu ike dị n’akụkụ ụgbọ elu GND, anya n’etiti ụgbọ elu ahụ pere mpe, yana ọ nwere mmetụta kagbuo ndọta ndọta kacha mma yana mgbochi ikuku ụgbọ elu dị ala.

(3) Isi ọkọnọ ọkụ na akwa ala ya dabara na oyi akwa 4 na 5. Mgbe edobere oke ọkpụrụkpụ, ekwesịrị ịbawanye oghere dị n’etiti S2-P yana ekwesịrị ibelata oghere dị n’etiti P-G2 (oghere dị n’etiti akwa Ekwesịrị ibelata G1-S2), iji belata impedance nke ụgbọ elu ike yana mmetụta nke ike ọkọnọ na S2.

Maka ọkwa isii, nhọrọ 4

Nyocha:

Atụmatụ 4 dabara adaba karịa atụmatụ 3 maka mpaghara, obere akara chọrọ, nke nwere ike ịnye akwa oyi akwa S2.

Mmetụta EMC kachasị njọ, atụmatụ 2

Nkọwa: N’ime ihe owuwu a, S1 na S2 dị n’akụkụ, S3 na S4 dị n’akụkụ, yana S3 na S4 adịghị n’akụkụ ụgbọ elu ala, yabụ mmetụta ndọghachi ndọta ndọta adịghị mma.

ọgwụgwụ

Ụkpụrụ akọwapụtara nke imebe akwa PCB:

(1) Enwere ụgbọ elu ala zuru oke (ọta) n’okpuru elu akụrụngwa na elu ịgbado ọkụ;

(2) Gbalịa izere n’akụkụ dị n’akụkụ ọkwa mgbaama abụọ;

(3) Ogwe mgbaama niile dị n’akụkụ ụgbọ elu ala ka o kwere mee;

(4) Mpekere wired nke ugboro ugboro dị elu, oke ọsọ, elekere na akara igodo ndị ọzọ kwesịrị ịnwe ụgbọ elu dị n’akụkụ.