Asanayambe kupanga Mipikisano PCB board, wopanga amayenera kudziwa kaye mawonekedwe a board board omwe amagwiritsidwa ntchito molingana ndi sikelo ya dera, kukula kwa board board ndi electromagnetic compatibility (EMC), ndiye kuti, kusankha ngati agwiritse ntchito zigawo 4, zigawo 6, kapena zigawo Zambiri zama board ozungulira. . Pambuyo pozindikira kuchuluka kwa zigawo, dziwani komwe mungayikidwe magetsi amkati ndi momwe mungagawire zizindikiro zosiyana pazigawozi. Uku ndiye kusankha kwa multilayer PCB stack.

Kapangidwe ka laminated ndichinthu chofunikira chomwe chimakhudza magwiridwe antchito a EMC pama board a PCB, komanso ndi njira yofunika kupondereza kusokonezedwa kwa ma elekitiroma. Nkhaniyi ikuwonetsa zomwe zili mu multilayer PCB board stack.

After determining the number of power, ground and signal layers, the relative arrangement of them is a topic that every PCB engineer cannot avoid;

Mfundo yaikulu ya dongosolo la layer:

1. Kuti mudziwe mawonekedwe a laminated a multilayer PCB board, zinthu zambiri ziyenera kuganiziridwa. Kuchokera pamawonekedwe a mawaya, zigawo zowonjezereka, zimakhala bwino kwambiri, koma mtengo ndi zovuta za kupanga bolodi zidzawonjezekanso. Kwa opanga, kaya kapangidwe ka laminated ndi symmetrical kapena ayi ndi cholinga chimene chiyenera kulipidwa pamene matabwa PCB amapangidwa, kotero kusankha chiwerengero cha zigawo ayenera kuganizira zofuna za mbali zonse kukwaniritsa bwino bwino. Kwa okonza odziwa, akamaliza chisanadze masanjidwe a zigawo zikuluzikulu, iwo kuganizira kusanthula PCB mawaya bottleneck. Phatikizani ndi zida zina za EDA kuti mufufuze kuchuluka kwa ma waya a board board; ndiye phatikizani nambala ndi mitundu ya mizere yolumikizira yomwe ili ndi zofunikira zapadera zamawaya, monga mizere yosiyana, mizere yodziwika bwino, ndi zina zambiri, kuti mudziwe kuchuluka kwa zigawo zazizindikiro; ndiye molingana ndi mtundu wa magetsi, kudzipatula ndi kusokoneza Zofunikira kuti mudziwe kuchuluka kwa zigawo zamagetsi zamkati. Mwanjira imeneyi, kuchuluka kwa zigawo za bolodi lonse ladera kumatsimikiziridwa.

2. The bottom of the component surface (the second layer) is the ground plane, which provides the device shielding layer and the reference plane for the top wiring; the sensitive signal layer should be adjacent to an internal electrical layer (internal power/ground layer), using the large internal electrical layer Copper film to provide shielding for the signal layer. The high-speed signal transmission layer in the circuit should be a signal intermediate layer and sandwiched between two inner electrical layers. In this way, the copper film of the two inner electric layers can provide electromagnetic shielding for high-speed signal transmission, and at the same time, it can effectively limit the radiation of the high-speed signal between the two inner electric layers without causing external interference.

3. Zigawo zonse za chizindikiro zili pafupi kwambiri ndi ndege yapansi;

4. Yesetsani kupewa magawo awiri azizindikiro omwe ali pafupi ndi mnzake; ndikosavuta kuyambitsa crosstalk pakati pa zigawo zoyandikana, zomwe zimapangitsa kuti ntchito yozungulira iwonongeke. Kuonjezera ndege yapansi pakati pa zigawo ziwiri zazizindikiro zingathe kupeweratu crosstalk.

5. Gwero lalikulu lamphamvu lili pafupi kwambiri ndi momwe lingathere;

6. Ganizirani zofananira za kapangidwe ka laminated.

7. Kwa masanjidwe a bolodi la mavabodi, ndizovuta kuti mavabodi omwe alipo kuti azitha kuwongolera mawaya akutali. Pamaulendo opangira ma board omwe ali pamwamba pa 50MHZ (onani zomwe zili pansipa 50MHZ, chonde pumulani moyenera), tikulimbikitsidwa kukonza mfundoyi:

Chigawo pamwamba ndi kuwotcherera pamwamba ndi wathunthu pansi ndege (chishango);Palibe moyandikana kufanana mawaya zigawo;Zigawo zonse chizindikiro ali pafupi kwambiri ndi pansi ndege;

Chizindikiro chofunikira chili moyandikana ndi pansi ndipo sichidutsa gawolo.

Zindikirani: Mukakhazikitsa zigawo za PCB, mfundo zomwe zili pamwambazi ziyenera kukhala zosinthika. Malingana ndi kumvetsetsa kwa mfundo zomwe zili pamwambazi, malingana ndi zofunikira zenizeni za bolodi limodzi, monga: ngati chingwe chachikulu cha mawaya, magetsi, kugawanika kwa ndege kumafunika, ndi zina zotero. Osati kungoyikopera mosabisa, kapena gwiritsitsani izo.

8. Zigawo zambiri zamagetsi zokhazikika mkati zimatha kuchepetsa kutsekeka kwa nthaka. Mwachitsanzo, chizindikiro cha A ndi chizindikiro cha B chimagwiritsa ntchito ndege zosiyana, zomwe zingathe kuchepetsa kusokoneza wamba.

Chomwe chimagwiritsidwa ntchito kwambiri chosanjikiza: 4-wosanjikiza bolodi

Zotsatirazi zimagwiritsa ntchito chitsanzo cha bolodi la 4-wosanjikiza kufotokoza momwe mungakwaniritsire makonzedwe ndi kuphatikiza mitundu yosiyanasiyana ya laminated.

Kwa matabwa a 4-wosanjikiza omwe amagwiritsidwa ntchito kwambiri, pali njira zowunjikira zotsatirazi (kuyambira pamwamba mpaka pansi).

(1) Siganl_1 (Pamwamba), GND (Inner_1), MPHAMVU (Inner_2), Siganl_2 (Pansi).

(2) Siganl_1 (Pamwamba), MPHAMVU (Inner_1), GND (Inner_2), Siganl_2 (Pansi).

(3) POWER (Top), Siganl_1 (Inner_1), GND (Inner_2), Siganl_2 (Bottom).

Mwachiwonekere, Njira 3 ilibe mgwirizano wothandiza pakati pa gawo la mphamvu ndi nthaka ndipo siyenera kutengedwa.

Ndiye kodi zosankha 1 ndi 2 ziyenera kusankhidwa bwanji?

Under normal circumstances, designers will choose option 1 as the structure of the 4-layer board. The reason for the choice is not that Option 2 cannot be adopted, but that the general PCB board only places components on the top layer, so it is more appropriate to adopt Option 1.

Koma pamene zigawo ziyenera kuikidwa pamwamba ndi pansi, ndipo makulidwe a dielectric pakati pa mphamvu ya mkati ndi pansi ndi yaikulu ndipo kugwirizanitsa kumakhala kovutirapo, m’pofunika kuganizira kuti ndi gawo liti lomwe lili ndi mizere yocheperapo. Posankha 1, pali mizere yocheperako yocheperako pansi, ndipo filimu yamkuwa yayikulu ingagwiritsidwe ntchito kuphatikiza ndi POWER wosanjikiza; m’malo mwake, ngati zigawozo zakonzedwa makamaka pansi wosanjikiza, Njira 2 iyenera kugwiritsidwa ntchito kupanga bolodi.

Ngati mawonekedwe a laminated atengedwa, gawo la mphamvu ndi gawo la pansi zimagwirizanitsidwa kale. Poganizira zofunikira za symmetry, chiwembu 1 chimatengedwa nthawi zambiri.

6-wosanjikiza bolodi

Pambuyo pomaliza kusanthula kamangidwe ka laminated la 4-layer board, zotsatirazi zimagwiritsa ntchito chitsanzo cha 6-wosanjikiza gulu lophatikizana kuti liwonetsere makonzedwe ndi kuphatikiza kwa bolodi la 6 ndi njira yokondedwa.

(1) Siganl_1 (Pamwamba), GND (Inner_1), Siganl_2 (Inner_2), Siganl_3 (Inner_3), mphamvu (Inner_4), Siganl_4 (Pansi).

Njira yothetsera 1 imagwiritsa ntchito zigawo za zizindikiro za 4 ndi zigawo za 2 zamkati za mphamvu / pansi, zokhala ndi zizindikiro zowonjezereka, zomwe zimagwirizana ndi ntchito ya waya pakati pa zigawo zikuluzikulu, koma zolakwika za yankholi zikuwonekeranso, zomwe zikuwonetsedwa muzinthu ziwiri zotsatirazi:

① Ndege yamagetsi ndi ndege yapansi ndizotalikirana, ndipo sizilumikizana mokwanira.

② Chizindikiro cha chizindikiro Siganl_2 (Inner_2) ndi Siganl_3 (Inner_3) ali pafupi, kotero kudzipatula kwa chizindikiro sikwabwino ndipo crosstalk ndiyosavuta kuchitika.

(2) Siganl_1 (Pamwamba), Siganl_2 (Inner_1), MPHAMVU (Inner_2), GND (Inner_3), Siganl_3 (Inner_4), Siganl_4 (Pansi).

Chiwembu 2 Poyerekeza ndi chiwembu 1, gawo lamagetsi ndi ndege yapansi zimaphatikizidwa kwathunthu, zomwe zili ndi zabwino zina pa chiwembu 1, koma

Zigawo za Siganl_1 (Pamwamba) ndi Siganl_2 (Inner_1) ndi Siganl_3 (Inner_4) ndi Siganl_4 (Pansi) zimayandikana. Kudzipatula kwazizindikiro sikwabwino, ndipo vuto la crosstalk silimathetsedwa.

(3) Siganl_1 (Pamwamba), GND (Inner_1), Siganl_2 (Inner_2), MPHAMVU (Inner_3), GND (Inner_4), Siganl_3 (Pansi).

Poyerekeza ndi Scheme 1 ndi Scheme 2, Scheme 3 ili ndi siginecha imodzi yocheperako komanso gawo lina lamagetsi lamkati. Ngakhale zigawo zomwe zilipo zopangira mawaya zimachepetsedwa, dongosololi limathetsa zolakwika zomwe zimachitika pa Scheme 1 ndi Scheme 2.

① Ndege yamagetsi ndi ndege yapansi zimalumikizidwa mwamphamvu.

② Chigawo chilichonse cha siginecha chimakhala moyandikana ndi chingwe chamkati chamagetsi, ndipo chimasiyanitsidwa bwino ndi zigawo zina zazizindikiro, ndipo crosstalk sizovuta kuchitika.

③ Siganl_2 (Inner_2) ili pafupi ndi zigawo ziwiri zamagetsi zamkati GND (Inner_1) ndi MPHAMVU (Inner_3), zomwe zingagwiritsidwe ntchito potumiza zizindikiro zothamanga kwambiri. Zigawo ziwiri zamagetsi zamkati zimatha kuteteza bwino kusokoneza kuchokera kudziko lakunja kupita ku Siganl_2 (Inner_2) wosanjikiza ndi kusokoneza kwa Siganl_2 (Inner_2) kupita kudziko lakunja.

M’mbali zonse, chiwembu 3 mwachiwonekere ndichokonzedwa bwino kwambiri. Panthawi imodzimodziyo, chiwembu 3 chimagwiritsidwanso ntchito kwambiri pamatabwa a 6-wosanjikiza. Kupyolera mu kufufuza kwa zitsanzo ziwiri zomwe zili pamwambazi, ndikukhulupirira kuti wowerenga ali ndi chidziwitso chodziwika bwino cha dongosolo la cascading, koma nthawi zina, dongosolo linalake silingathe kukwaniritsa zofunikira zonse, zomwe zimafuna kulingalira za kuika patsogolo kwa mfundo zosiyanasiyana za mapangidwe. Mwatsoka, chifukwa chakuti dera gulu wosanjikiza kamangidwe zimagwirizana kwambiri ndi makhalidwe a dera lenileni, ndi odana kusokoneza ntchito ndi kamangidwe kuganizira madera osiyanasiyana ndi osiyana, choncho mfundo zimenezi alibe anatsimikiza patsogolo kutchulidwa. Koma chotsimikizika ndichakuti kapangidwe ka pulani 2 (gawo lamphamvu lamkati ndi gawo la pansi liyenera kulumikizidwa mwamphamvu) liyenera kukumana koyamba pamapangidwewo, ndipo ngati ma siginecha othamanga kwambiri akufunika kufalikira kuzungulira, ndiye kuti kapangidwe kake 3 (wosanjikiza wothamanga wamakina othamanga kwambiri mumayendedwe) Iyenera kukhala yosanjikiza yapakati komanso yokhazikika pakati pa zigawo ziwiri zamkati zamagetsi) iyenera kukhutitsidwa.

10-wosanjikiza bolodi

PCB wamba 10-wosanjikiza bolodi kapangidwe

Mawaya onse amatsata TOP-GND—signal layer—power layer—GND—signal layer—power layer—signal layer—GND—BOTTOM

Kutsatizana kwa mawaya palokha sikukhazikika, koma pali mfundo ndi mfundo zoletsa: Mwachitsanzo, zigawo zoyandikana ndi pamwamba ndi pansi zimagwiritsa ntchito GND kuti zitsimikizire kuti EMC ili ndi bolodi limodzi; mwachitsanzo, aliyense wosanjikiza chizindikiro makamaka amagwiritsa GND wosanjikiza monga ndege ndege; magetsi omwe amagwiritsidwa ntchito pa bolodi limodzi lonse amayikidwa mwapadera pamtundu wonse wamkuwa; wotengeka, wothamanga kwambiri, ndipo amakonda kupita pamzere wamkati wa kulumpha, etc.