Papa Pai Kaapuni (PCB), i ʻike ʻia ʻo Printed Circuit Board (PCB), hoʻohana ʻia e hoʻohui a hana i nā ʻenehana uila a he ʻāpana nui ia o ka hoʻolālā Kaapuni mana. E hoʻolauna kēia ʻatikala i nā lula kumu o ka hoʻonohonoho PCB a me nā pilina.

ʻIke i nā lula maʻamau o ka hoʻonohonoho papa PCB a me nā pilina

Basic rules of component layout

1. According to the layout of circuit modules, the related circuit to achieve the same function is called a module, the components in the circuit module should adopt the principle of nearby concentration, and the digital circuit and analog circuit should be separated;

2. ʻAʻole e hoʻokomo ʻia nā mea hana, nā hāmeʻa a me nā wili i loko o 3.5mm (no M2.5) a me 4mm (no M3) a puni nā puka kū ʻole e like me nā puka hoʻonohonoho a me nā puka maʻamau ma loko o 1.27mm;

3. Horizontal resistance, inductor (plug-in), electrolytic capacitor and other components under the cloth hole, so as to avoid the wave soldering hole and component shell short circuit;

4. ʻO ka ʻaoʻao i waho o ka mea hoʻohui he 5mm mai ka lihi o ka pā;

5. The distance between the outer side of the pad of mounting element and the outer side of the adjacent inserting element is greater than 2mm;

6. Metal shell components and metal parts (shielding boxes, etc.) can not touch other components, can not be close to the printed line, pad, the spacing should be greater than 2mm. The size of positioning holes, fastener mounting holes, elliptic holes and other square holes in the plate is greater than 3mm from the plate side;

7. ʻAʻole kokoke nā mea hoʻomehana i nā kaula a me nā mea wela; High-heat devices should be evenly distributed;

8. Pono e hoʻonohonoho ʻia ke kumu o ka mana a puni ka papa pai i ka hiki, a me ke kikowaena uwea o ke kumu mana a me ka busbar e pili ana iā ia e hoʻonohonoho pono ma ka ʻaoʻao like. Ma kahi kikoʻī, mai hoʻokau i nā kumu uila a me nā mea hoʻopili hoʻohui ʻē aʻe ma waena o nā mea hoʻopili e hoʻoikaika i ka hoʻopili ʻana o kēia mau kumu a me nā mea hoʻopili a me ka hoʻolālā a me nā uea o nā kaula uila. The spacing of power sockets and welding connectors should be considered to facilitate the insertion and removal of power plugs;

9. Layout o nā ʻāpana ʻē aʻe:

All IC components should be aligned unilaterally, and polarity marks of polar components should be clear. Polarity marks on the same printed board should not be more than two directions. When two directions appear, the two directions should be perpendicular to each other.

10, the surface wiring should be properly dense, when the density difference is too large should be filled with mesh copper foil, the grid is greater than 8mil (or 0.2mm);

11, the patch pad can not have through holes, so as to avoid the loss of solder paste resulting in virtual welding components. ʻAʻole ʻae ʻia ka laina hōʻailona koʻikoʻi e hele ma waena o ka wāwae kumu;

12, hoʻopili i ka hoʻopili unilateral, ke ʻano o ke ʻano o ke ʻano, ke kuhikuhi ʻōpala kūlike;

13. Polar devices should be marked in the same direction as far as possible on the same board.

ʻElua, nā rula hoʻohui uila

1. E kahakiʻi i nā wahi pilina i loko o ka ≤1mm mai ka lihi papa PCB, a ma loko o 1mm a puni ka puka piʻi, a pāpā i ka hoʻopili ʻana;

2. ʻO ka laina uila i ka laulā e hiki ai, ʻaʻole pono ma lalo o 18mil; Signal line width should not be less than 12mil; CPU incoming and outgoing lines should not be less than 10mil (or 8mil); Ke laina laina ʻaʻole emi ma lalo o 10mil;

3. ʻAʻole emi ka lua maʻamau ma mua o 30mil;

4. Hoʻokomo laina laina pālua: pad 60mil, puka 40mil;

Kūʻē 1 / 4W: 51 * 55mil (0805 ʻāpana); Hoʻokomo pololei i ka pale 62mil, puka 42mil;

Non-polar capacitor: 51*55mil (0805 sheet); Hoʻokomo pololei i ka pale 50mil, puka 28mil;

5. E hoʻomaopopo he radial nā kaula uila a me nā kaula o ka honua i ka hiki, a ʻaʻole pono e hoʻopili ʻia nā kaula hōʻailona.

Pehea e hoʻomaikaʻi ai i ka hiki i ka anti-interferensience a me ka hoʻokaulike electromagnetic?

Pehea e hoʻomaikaʻi ai i ka hiki i ka anti-interferensience a me ka hoʻohālikelike electromagnetic ke hoʻomohala ʻana i nā huahana uila me ka mīkini.

1. Pono e nānā i kekahi o nā ʻōnaehana i lalo i ka hana kūikawā anti-electromagnetic:

(1) kiʻekiʻe kiʻekiʻe ka pinepine o ka uaki microcontroller, ʻōnaehana wikiwiki hoʻi ke kaʻa ʻōhua.

(2) Aia i loko o ka ʻōnaehana ka mana nui, kaapuni hoʻokele kiʻekiʻe i kēia manawa, e like me ka hoʻoulu ʻana i ka mika, ke kuapo kiʻekiʻe o kēia manawa, a pēlā aku.

(3) ʻōnaehana me ka pōʻaiapili hōʻailona analog nāwaliwali a me ke kaapuni hoʻohuli kiʻekiʻe A / D kiʻekiʻe.

2. Lawe ʻia nā ana aʻe e hoʻonui ai i ka hiki i ka anti-electromagnetic interference capability o ka ʻōnaehana.

(1) Koho i ka microcontroller me ka pinepine haʻahaʻa:

Hiki i ka microcontroller me ka pinepine o ka uaki uaki i waho ke hiki ke hōʻemi pono i ka walaʻau a hoʻomaikaʻi i ka hiki anti-interferensience o ka ʻōnaehana. Nalu ʻāhaʻi a me ka nalu sine me ke alapine like, ʻo ka ʻāpana alapine kiʻekiʻe o ka nalu ʻāpana ʻoi aku ka nui ma mua o ka nalu sine. ʻOiai ʻoi aku ka liʻiliʻi o ka amplitude o ke kiʻekiʻena alapine o ka nalu square ma mua o ka nalu kumu, ʻo ke kiʻekiʻe ke alapine, ʻoi aku ka maʻalahi o ka emit a lilo i kumu halulu. ʻO ke kani pinepine pinepine kiʻekiʻe i hana ʻia e ka microcontroller ma kahi o 3 mau manawa o ka uaki pinepine.

(2) E ho’ēmi i ke kuhi hewa i ka lawe ʻana o ka hōʻailona

Hana ʻia nā Microcontrollers e ka ʻenehana wikiwiki ʻo CMOS kiʻekiʻe. Static input current signal input at about 1 ma, around ten pf in the input capacitance, high input impedance, high speed CMOS circuit outputs are fairly on load capacity, namely the considerable output value, the output end of a door through a very long lead to the high input, the input impedance reflection problem is very serious, it will cause the signal distortion, Hoʻonui i ka walaʻau ʻōnaehana. Ke Tpd “Tr”, lilo ia i pilikia laina hoʻoili, pono e noʻonoʻo i ke aniani hōʻailona, ​​ke kaulike impedance a pēlā aku.

ʻO ka manawa lohi o ka hōʻailona ma ka papa pai e pili ana i ka impedance ʻano o ke kēpau, ʻo ia hoʻi, i ka hoʻomau dielectric o nā mea papa i pai ʻia. Hiki ke noʻonoʻo maʻalahi i nā hōʻailona e hele ma waena o 1/3 a me 1/2 ka wikiwiki o ke kukui ma luna o nā alakaʻi PCB. ʻO ka Tr (manawa lohi maʻamau) o nā mea kelepona loea i hoʻohana pinepine ʻia i nā ʻōnaehana i hana ʻia o nā microcontrollers ma waena o 3 a me 18ns.

On the printed circuit board, the signal passes through a 7W resistor and a 25cm lead, with an on-line delay of approximately 4 to 20ns. That is to say, the signal on the printed line lead as short as possible, the longest should not exceed 25cm. A ʻo ka helu o nā lua he mea liʻiliʻi ia, ʻoi aku ka maikaʻi ma mua o 2.

Ke piʻi wikiwiki ka hōʻailona hōʻailona ma mua o ka manawa lohi o ka hōʻailona, ​​hoʻopili ʻia ka uila uila. I kēia manawa, pono e noʻonoʻo ʻia ka hoʻohālikelike impedance o ka laina hoʻoili. No ka lawe ʻana o ka hōʻailona ma waena o nā poloka i hoʻopili ʻia ma ka papa kaapuni PRINTED, pono e hōʻalo ʻia ʻo Td Trd. ʻO ka nui o ka papa kaapuni i paʻi ʻia, ʻo ka wikiwiki o ka ʻōnaehana ʻaʻole hiki ke wikiwiki.