With the progress of electronic technology, the complexity of PCB (ibhodi yesifunda ephrintiwe), ubukhulu besicelo bunentuthuko esheshayo. Designers engaged in HF PCB must have relevant basic theoretical knowledge and rich experience in THE manufacture of HF PCB. In other words, both schematic drawing and PCB design should be considered from the high-frequency working environment, so as to design a more ideal PCB.

Leli phepha, i-wiring ye-PCB, ipuleti le-welding futhi lisebenzisa indlela yokwakha yethusi, okokuqala, kusisekelo se-wiring ye-PCB, i-wiring, intambo yamandla kanye nezidingo zokwenza izintambo phansi ngendlela yephepha lethula ukwakheka I-wiring ye-PCB, eyesibili kusukela kuphedi yokuxhuma nokuvuleka, usayizi wephedi le-PCB nokwakheka komklamo ekwakhiweni okujwayelekile, izidingo zepads yenqubo yokukhiqiza ye-PCB yethulwa ukwakheka kwe-PCB solder, Finally, from the PCB copper coating skills and Settings introduced the PCB copper coating design, specific follow xiaobian to understand.

Incazelo eningiliziwe yendlela yokuklanywa ye-PCB wiring, i-welding pad ne-coating yethusi

PCB wiring design

Ukwenza izintambo kuyisidingo esijwayelekile sokwakhiwa kwe-hf PCB ngokuya ngesakhiwo esikahle. Cabling includes automatic cabling and manual cabling. Imvamisa, noma ngabe kunemigqa emikhulu kangakanani yesiginali, kufanele kwenziwe izintambo mathupha kule mizila yesiginali kuqala. Ngemuva kokuphothulwa kwentambo, ukuxhunywa kwale migqa yesiginali kufanele kuhlolwe ngokucophelela futhi kulungiswe ngemuva kokudlulisa isheke, bese kuthi ezinye izintambo zifakwe izintambo ngokuzenzakalela. Okusho ukuthi, ukuhlanganiswa kwe-wiring yesandla kanye ne-othomathikhi kusetshenziselwa ukuqedela izintambo ze-PCB.

The following aspects should be paid special attention to during the wiring of hf PCB.

1. Ukuqondiswa kwentambo

The wiring of the circuit is best to adopt a full straight line according to the direction of the signal, and 45° broken line or arc curve can be used to complete the turning point, so as to reduce the external emission and mutual coupling of high-frequency signals. Ukuxhunywa kwezintambo zesiginali ephezulu kufanele kube kufushane ngangokunokwenzeka. Ngokuya ngemvamisa yokusebenza kwesekethe, ubude bolayini wesiginali kufanele bukhethwe ngokufanele, ukunciphisa imingcele yokusabalalisa nokunciphisa ukulahleka kwesiginali. Lapho wenza amapaneli aphindwe kabili, kungcono ukuhambisa izingqimba ezimbili ezincikene zibheke phezulu, zihlukane noma zigobile ukuze zihlangane. Gwema ukufana komunye nomunye, okunciphisa ukuphazanyiswa kokuhlangana nokuhlangana kwezinambuzane.

Imigqa yesiginali yemvamisa ephezulu kanye nolayini bezimpawu zamaza aphansi kufanele bahlukaniswe ngangokunokwenzeka, futhi kufanele kuthathwe izinyathelo zokuvikela lapho kunesidingo ukuvimbela ukuphazamiseka okuhlangene. Ukuze okokufaka kwesiginali kutholakale kubuthakathaka okulula, okulula ukuphazanyiswa amasiginali wangaphandle, ungasebenzisa ucingo lwasemhlabeni ukwenza ukuvikela ukuluzungeza noma wenze umsebenzi omuhle wokuvikela isixhumi samaza aphezulu. Parallel wiring should be avoided on the same level, otherwise distributed parameters will be introduced, which will affect the circuit. If unavoidable, a grounded copper foil can be introduced between the two parallel lines to form an isolation line.

In the digital circuit, for differential signal lines, should be in pairs, as far as possible to make them parallel, close to some, and the length is not much different.

2. Uhlobo lwezintambo

Ku-wiring ye-PCB, ububanzi obuncane bezintambo bunqunywa ngamandla wokubambelela phakathi kocingo kanye ne-insulator substrate namandla wamanje ogeleza ocingweni. Lapho ukushuba kocwecwe lwethusi kungu-0.05mm nobubanzi bungu-1mm-1.5mm, 2A yamanje ingadluliselwa. Izinga lokushisa akumele libe ngaphezu kuka-3 ℃. Ngaphandle kwezinye izintambo ezikhethekile, ububanzi benye intambo kusendlalelo olufanayo kufanele buhambisane ngangokunokwenzeka. Kwisifunda esinemvamisa ephezulu, ukuhlukaniswa kwezintambo kuzothinta ubukhulu be-capacitance nokusatshalaliswa okusatshalalisiwe, futhi ngaleyo ndlela kuthinte ukulahleka kwesiginali, ukuzinza kwesifunda nokuphazamiseka kwesiginali. In high speed switching circuit, wire spacing will affect signal transmission time and waveform quality. Ngakho-ke, isikhala esincane sezintambo kufanele sibe sikhulu noma silingane no-0.5 mm. Kungcono ukusebenzisa imigqa ebanzi ngentambo ye-PCB lapho kungenzeka khona.

There should be a certain distance between the printed wire and the edge of the PCB (no less than the thickness of the plate), which is not only easy to install and machining, but also improve the insulation performance.

When wiring can only be connected around a large circle of the line, we should use the flying line, that is, directly connected with short line to reduce the interference brought by long-distance wiring.

The circuit containing magnetic sensitive elements is sensitive to the surrounding magnetic field, while the bend of wiring of high-frequency circuit is easy to radiate electromagnetic wave. If magnetic sensitive elements are placed in PCB, it should ensure that there is a certain distance between the corner of wiring and it.

Ayikho i-crossover evunyelwe ezingeni elifanayo lezintambo. For the line that may cross, can use “drill” with “wound” method to solve, let a certain lead namely from other resistance, capacitance, audion etc. device lead foot gap place “drill” past, or from the end of a certain lead that may cross “wound” past. Ezimweni ezikhethekile lapho isifunda siyinkimbinkimbi kakhulu, ukwenza umklamo ube lula, kuvunyelwe futhi ukuxazulula inkinga ye-crossover ngocingo olubopha.

Lapho imjikelezo ephezulu kakhulu isebenza kumvamisa ophakeme, ukufaniswa kwe-impedance kanye nomphumela we-antenna wiring kufanele futhi kubhekwe.

Because the client finally changed the previous agreement and required the interface definition and placement as defined by them, they had to change the layout to the diagram on the right. In fact, the entire PCB is only 9cm x 6cm. It is difficult to change the overall layout of the board according to the requirements of customers, so the core part of the board was not changed in the end, but the peripheral components were modified appropriately, mainly the position of the two connectors and the definition of pins were modified.

But the new layout obviously caused some trouble in the line, the original smooth line became a little messy, the length of the line increased, but also had to use a lot of holes, the difficulty of the line increased a lot.

Incazelo eningiliziwe yendlela yokuklanywa ye-PCB wiring, i-welding pad ne-coating yethusi

It is clear from this example that layout differences can have an impact on PCB design.

Incazelo eningiliziwe yendlela yokuklanywa ye-PCB wiring, i-welding pad ne-coating yethusi

3. Wiring requirements for power cables and ground cables

Khulisa ububanzi bezintambo zamandla ngokusho kwamanje okusebenza okuhlukile. I-Hf PCB kufanele yamukele indawo enkulu yocingo lomhlaba nokuhlelwa onqenqemeni lwe-PCB ngangokunokwenzeka, okunganciphisa ukuphazanyiswa kwesiginali yangaphandle kusekethe; At the same time, the grounding wire of PCB can be in good contact with the shell, so that the grounding voltage of PCB is closer to the earth voltage. The grounding mode should be selected according to the actual situation. Different from the low-frequency circuit, the grounding cable of the high-frequency circuit should be nearby or multi-point grounding. The grounding cable should be short and thick to minimize the ground impedance, and the allowable current should be three times of the working current. Isipikha esisekela ucingo kufanele sixhunywe ku-PCB power amplifier output level grounding point, ungazibekeli phansi ngokuthanda kwakho.

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