Definizzjoni ta ‘ high-frequency PCB board

Bord ta ‘frekwenza għolja jirreferi għall-bord ta’ ċirkwit ta ‘frekwenza elettromanjetika speċjali, użat fi frekwenza għolja (aktar minn 300 MHZ frekwenza jew wavelength huwa inqas minn metru) u microwave (akbar minn 1 GHZ frekwenza jew wavelength huwa inqas minn 3 metri) fil-qasam ta’ PCB, huwa fuq il-bażi tar-ram miksi miksi bl-użu ta ‘metodu ta’ manifattura ta ‘bord ta’ ċirkwit riġidu komuni ta ‘parti mill-proċess jew l-użu ta’ metodi ta ‘pproċessar speċjali u l-produzzjoni ta’ bordijiet ta ‘ċirkwiti. B’mod ġenerali, bordijiet ta ‘frekwenza għolja jistgħu jiġu definiti bħala bordijiet ta’ ċirkwiti bi frekwenzi ‘l fuq minn 1 GHz.

With the rapid development of science and technology, more and more equipment design is in the microwave band (> 1GHZ) and even with the millimeter wave field (30GHZ) above the application, which also means that the frequency is higher and higher, the substrate of the circuit board requirements are also higher and higher. Pereżempju, il-materjali tas-sottostrat jeħtieġ li jkollhom proprjetajiet elettriċi eċċellenti, stabbiltà kimika tajba, biż-żieda tal-frekwenza tas-sinjal tal-enerġija fir-rekwiżiti tat-telf tas-sottostrat huma żgħar ħafna, għalhekk l-importanza tal-pjanċa ta ‘frekwenza għolja hija enfasizzata.

Classification of PCB high frequency plate

1, at the end of the ceramic filled thermosetting material

Metodu ta ‘proċessar:

U raża epoxy / drapp minsuġ tal-ħġieġ (FR4) proċess ta ‘proċessar simili, iżda l-pjanċa hija aktar fraġli, faċli biex tinkiser, tħaffir u żennuna għat-tħaffir tal-pjanċa tal-gong u l-ħajja tas-sikkina tal-gong hija mnaqqsa b’20%.

2. Materjal PTFE (polytetrafluoroethylene)

Metodu ta ‘proċessar:

1. Ftuħ tal-materjal: il-film protettiv għandu jinżamm biex jiġu evitati grif u indentazzjoni

2. It-trapan:

2.1 use a new drill (standard 130), one piece stacked is the best, the presser foot pressure is 40psi

2.2 Folja ta ‘l-aluminju bħala pjanċa ta’ l-għatu, imbagħad uża pjanċa ta ‘l-amina densa ta’ 1mm, issikka l-pjanċa PTFE

2.3 Daqqa t-trab mit-toqba bl-air gun wara t-tħaffir

2.4 Bl-iktar tagħmir tat-tħaffir stabbli, parametri tat-tħaffir (bażikament, iktar ma tkun żgħira t-toqba, iktar tkun mgħaġġla r-rata tat-tħaffir, iżgħar it-tagħbija taċ-Ċippa, inqas tkun ir-rata tar-ritorn)

3. The hole processing

Trattament tal-plażma jew trattament ta ‘attivazzjoni tas-sodju-naftalina huwa ta’ benefiċċju għall-metallizzazzjoni tal-pori

4. PTH sink tar-ram

4.1 Wara mikro-inċiżjoni (ir-rata ta ‘mikro-inċiżjoni ġiet ikkontrollata b’20 mikro-pulzier), il-pjanċa hija mitmugħa miċ-ċilindru li jneħħi ż-żejt fil-ġibda PTH

4.2 If necessary, go through the second PTH, just from the forecast? The cylinder began to enter the plate

5. The resistance welding

5.1 Pre-treatment: use acid washing plate instead of mechanical grinding plate

5.2 After pre-treatment, bake plate (90℃, 30min), brush green oil and cure

5.3 Three baking plates: one is 80℃, 100℃ and 150℃ for 30min each (if oil is found on the substrate surface, it can be reworked: wash off the green oil and reactivate it)

6. Gong board

Lay the white paper on the PTFE board circuit surface, and clamp it with fr-4 base plate or phenolic base plate with a thickness of 1.0mm and copper removal: As shown in the figure:

X’inhuma l-bordijiet ta ‘frekwenza għolja tal-PCB? PCB high frequency plate classification

Materjal tal-folja ta ‘frekwenza għolja u veloċità għolja

Meta tagħżel is-sottostrat għall-PCB għal ċirkwiti ta ‘frekwenza għolja, għandha tingħata konsiderazzjoni speċjali għall-karatteristiċi tal-varjazzjoni tal-materjal DK fi frekwenzi differenti. For the requirements of signal high-speed transmission or characteristic impedance control, DF and its performance under the conditions of frequency, temperature and humidity are mainly investigated.

Under the condition of frequency variation, the DK and DF values of general substrate materials change greatly. Speċjalment fil-medda ta ‘frekwenza minn L MHz sa L GHz, il-valuri DK u DF tagħhom jinbidlu b’mod aktar ovvju. For example, the GENERAL epoxy – glass fiber substrate material (general FR-4) has a DK value of 4.7 at lMHz and a DK value of 4.19 at lGHz. Fuq lGHz, il-valur DK tiegħu jinbidel bil-mod. For example, under l0GHz, the DK value of FR-4 is 4.15. For substrate materials with high speed and high frequency characteristics, the DK value changes slightly. From lMHz to lGHz, the DK value mostly stays within 0.02 range. The DK value tends to decrease slightly at different frequencies from low to high.

Il-fattur tat-telf dielettriku (DF) tal-materjal tas-substrat ġenerali huwa akbar minn dak ta ‘DK minħabba l-influwenza tal-varjazzjoni tal-frekwenza (speċjalment fil-medda ta’ frekwenza għolja). Għalhekk, meta nevalwaw il-karatteristiċi ta ‘frekwenza għolja ta’ materjal ta ‘sottostrat, għandna niffokaw fuq il-bidla tal-valur DF tiegħu. Il-materjali tas-substrat b’veloċità għolja u karatteristiċi ta ‘frekwenza għolja huma ovvjament differenti mill-materjali tas-substrat ġenerali f’termini tal-karatteristiċi tal-varjazzjoni fi frekwenza għolja. Waħda hija li bil-bidla fil-frekwenza, il-valur tagħha (DF) jinbidel ftit. L-ieħor huwa simili għall-materjal tas-substrat ġenerali fil-medda tal-varjazzjoni, iżda l-valur tiegħu (DF) huwa inqas.

How to choose high frequency high speed plate

L-għażla tal-bord tal-PCB għandha tissodisfa r-rekwiżiti tad-disinn, il-produzzjoni tal-massa u l-ispiża tal-bilanċ bejn. In short, the design requirements consist of two components: electrical and structural reliability. This is usually important when designing very high speed PCB boards (frequencies greater than GHz). Pereżempju, il-materjal fr-4 użat komunement illum jista ‘ma jkunx applikabbli minħabba d-Df kbir tiegħu (Dielectricloss) f’bosta frekwenzi GHz.

X’inhuma l-bordijiet ta ‘frekwenza għolja tal-PCB? PCB high frequency plate classification

For example, a 10Gb/S high-speed digital signal is a square wave, which can be regarded as a superposition of sinusoidal signals of different frequencies. Therefore, 10Gb/S contains many different frequency signals: 5Ghz fundamental signal, 3 order 15GHz, 5 order 25GHz, 7 order 35GHz signal, etc. L-integrità tas-sinjal diġitali u l-wieqaf tat-truf ta ‘fuq u ta’ isfel huma l-istess bħat-trasmissjoni ta ‘telf baxx u distorsjoni baxxa ta’ rf microwave (il-parti armonika ta ‘frekwenza għolja tas-sinjal diġitali tilħaq il-faxxa tal-microwave). Therefore, in many respects, the PCB material selection of high-speed digital circuits is similar to the requirements of RF microwave circuits.

X’inhuma l-bordijiet ta ‘frekwenza għolja tal-PCB? PCB high frequency plate classification

In practical engineering operations, the selection of high-frequency plates seems simple, but there are still many factors to be considered. Through the introduction of this paper, AS a PCB design engineer or a high-speed project leader, I have a certain understanding of the characteristics and selection of plates. Jifhmu proprjetajiet elettriċi, proprjetajiet termali, affidabilità, eċċ. And rational use of stacking, design a piece of high reliability, good processing products, various factors to consider the best.

Dan li ġej jintroduċi l-fatturi ewlenin li għandek tikkunsidra fl-għażla tal-pjanċa xierqa:

1, manifatturabilità:

Bħall-prestazzjoni tal-ippressar multiplu, il-prestazzjoni tat-temperatura, ir-reżistenza CAF / sħana u l-ebusija mekkanika (viskożità) (affidabbiltà tajba), il-klassifikazzjoni tan-nar;

2, with the product matching performance (electrical, performance stability, etc.) :

Telf baxx, parametri stabbli ta ‘Dk / Df, dispersjoni baxxa, koeffiċjent ta’ bidla żgħira bi frekwenza u ambjent, tolleranza żgħira tal-ħxuna tal-materjal u kontenut ta ‘gomma (kontroll ta’ impedenza tajba), jekk il-wajer huwa twil, ikkunsidra fojl tar-ram ta ‘ħruxija baxxa. In addition, simulation is needed in the early stage of high-speed circuit design, and simulation results are the reference standard for design. “Xingsen Technology – Agilent (veloċità għolja / frekwenza tar-RADJU) Laboratorju konġunt” solviet il-problema ta ‘prestazzjoni ta’ riżultati ta ‘simulazzjoni inkonsistenti u testijiet, u għamlet numru kbir ta’ simulazzjoni u verifika tat-test attwali ta ‘ċirku magħluq, permezz ta’ metodu uniku biex tinkiseb il-konsistenza ta ‘ simulazzjoni u kejl.

X’inhuma l-bordijiet ta ‘frekwenza għolja tal-PCB? PCB high frequency plate classification

3. Disponibbiltà f’waqtha tal-materjali:

Ħafna ċikli ta ‘akkwist ta’ pjanċi ta ‘frekwenza għolja huma twal ħafna, anke 2-3 xhur; In addition to the conventional high frequency plate RO4350 has inventory, many high frequency plates need to be provided by customers. Therefore, high frequency plate and manufacturers need to communicate well in advance, as soon as possible;

4. Fatturi tal-ispejjeż:

Depending on the price sensitivity of the product, whether it is a consumer product, or a telecommunications, medical, industrial, military application;

5. Applicability of laws and regulations, etc.

Biex tkun kompatibbli mar-regolamenti ambjentali ta ‘pajjiżi differenti u tissodisfa r-rekwiżiti ta’ RoHS u ħielsa mill-aloġenu.

Among the above factors, the running speed of high-speed digital circuit is the main factor to consider in PCB selection. The higher the circuit speed, the smaller the selected PCBDf value should be. Il-pjanċa taċ-ċirkwit b’telf medju u baxx tkun adattata għal ċirkwit diġitali ta ’10Gb / S; The plate with lower loss is suitable for 25Gb/s digital circuit; Panels b’telf ultra-baxx se jakkomodaw ċirkwiti diġitali aktar mgħaġġla u ta ‘veloċità għolja b’rati ta’ 50Gb / s jew ogħla.

From the material Df:

Df bejn 0.01 ~ 0.005 circuit board adattat għal-limitu massimu ta ’10Gb / S ċirkwit diġitali;

Df bejn 0.005 ~ 0.003 circuit board adattat għal-limitu massimu ta ’25Gb / S ċirkwit diġitali;

Circuit boards with Df not more than 0.0015 are suitable for 50Gb/S or higher speed digital circuits.

Commonly used high-speed plates are:

1), Rogers: RO4003, RO3003, RO4350, RO5880, etc

2), Taiyao TUC: Tuc862, 872SLK, 883, 933, eċċ

3), Panasonic: Megtron4, Megtron6, eċċ

4), Isola: FR408HR, IS620, IS680, eċċ

5) Nelco: N4000-13, N4000-13EPSI, eċċ

6), Dongguan Shengyi, Taizhou Wangling, Taixing Microwave, eċċ