The interconnect of buga kewaye hukumar tsarin ya haɗa da allon guntu-da-kewaye, haɗawa tsakanin PCB da haɗawa tsakanin PCB da na’urorin waje. In RF design, the electromagnetic characteristics at the interconnect point is one of the main problems faced by engineering design. This paper introduces various techniques of the above three types of interconnect design, including device installation methods, isolation of wiring and measures to reduce lead inductance.

Akwai alamun cewa ana ƙera allon da’irar da aka buga tare da ƙara mita. As data rates continue to increase, the bandwidth required for data transmission also pushes the signal frequency ceiling to 1GHz or higher. This high frequency signal technology, although far beyond the millimeter wave technology (30GHz), does involve RF and low-end microwave technology.

Hanyoyin ƙirar injiniya na RF dole ne su sami damar ɗaukar tasirin filin wutar lantarki mai ƙarfi wanda galibi ana samarwa a mitoci. Waɗannan filayen lantarki na iya haifar da sigina akan layin siginar da ke kusa ko layukan PCB, yana haifar da crosstalk da ba a so (tsangwama da jimlar hayaniya) da cutar da aikin tsarin. Backloss is mainly caused by impedance mismatch, which has the same effect on the signal as additive noise and interference.

High return loss has two negative effects: 1. The signal reflected back to the signal source will increase the noise of the system, making it more difficult for the receiver to distinguish noise from signal; 2. 2. Duk wata sigina da aka nuna za ta ƙasƙantar da ingancin siginar saboda siginar siginar shigarwa tana canzawa.

Kodayake tsarin dijital yana da haƙuri sosai saboda suna ma’amala da siginar 1 da 0 kawai, jituwa da aka samar lokacin bugun jini yana ƙaruwa da sauri yana sa siginar ta yi rauni a manyan mitoci. Kodayake gyaran kuskuren gaba zai iya kawar da wasu mummunan tasirin, ana amfani da ɓangaren bandwidth na tsarin don watsa bayanai marasa aiki, wanda ke haifar da lalacewar aiki. A better solution is to have RF effects that help rather than detract from signal integrity. It is recommended that the total return loss at the highest frequency of a digital system (usually a poor data point) be -25dB, equivalent to a VSWR of 1.1.

PCB design aims to be smaller, faster and less costly. For RFPCB, high-speed signals sometimes limit the miniaturization of PCB designs. A halin yanzu, babbar hanyar da za a magance matsalar murƙushewa ita ce gudanar da gudanar da haɗin ƙasa, gudanar da tazara tsakanin wayoyi da rage shigar gubar. Babban hanyar rage asarar dawowar shine daidaiton impedance. Wannan hanyar ta haɗa da ingantaccen sarrafa kayan rufi da warewar layin siginar aiki da layin ƙasa, musamman tsakanin yanayin layin siginar da ƙasa.

Saboda haɗin haɗin shine mafi ƙarancin haɗin gwiwa a cikin sarkar da’irar, a cikin ƙirar RF, kaddarorin electromagnetic na ma’anar haɗin kai shine babban matsalar da ke fuskantar ƙirar injiniya, yakamata a bincika kowane hanyar haɗin kai kuma a warware matsalolin da ke akwai. Haɗin jirgin da’irar ya haɗa da haɗin guntu-zuwa-kewaye, haɗin PCB da shigarwar siginar/haɗin haɗin fitarwa tsakanin PCB da na’urorin waje.

I. Haɗin kai tsakanin guntu da allon PCB

Ko wannan maganin yana aiki ko a’a, a bayyane yake ga masu halarta cewa fasahar ƙirar IC tana gaban fasahar ƙirar PCB don aikace -aikacen hf.

Haɗin PCB

Dabaru da hanyoyin don ƙirar PCB hf sune kamar haka:

1. Yakamata a yi amfani da Angle 45 ° don kusurwar layin watsawa don rage asarar dawowar (FIG. 1);

2 rufi m darajar bisa ga matakin tsananin sarrafawa high-yi rufi kewaye hukumar. This method is beneficial for effective management of electromagnetic field between insulating material and adjacent wiring.

3. Dole ne a inganta takamaiman ƙirar PCB don babban daidaitaccen etching. Yi la’akari da tantance kuskuren faɗin layin gaba ɗaya na +/- 0.0007 inci, sarrafa ƙasan da ƙetare na sassan wayoyi da tantance yanayin bangon bango na gefe. Overall management of wiring (wire) geometry and coating surfaces is important to address skin effects related to microwave frequencies and to implement these specifications.

4. Akwai inductance famfo a cikin fitattun jagororin. Kauce wa amfani da aka gyara tare da jagoranci. Don yanayin maɗaukaki, yana da kyau a yi amfani da abubuwan da aka ɗora akan farfajiya.

5. Don sigina ta cikin ramuka, guji amfani da tsarin PTH akan farantin mai mahimmanci, saboda wannan tsarin na iya haifar da shigar gubar a ramin. Lead inductance can affect layers 4 to 19 if a through-hole in a 20-ply board is used to connect layers 1 to 3.

6. Samar da yalwar yalwar ƙasa. Moulded holes are used to connect these grounding layers to prevent 3d electromagnetic fields from affecting the circuit board.

7. Don zaɓar abin da ba na electrolysis nickel plating ko nutsewar tsarin zinare na zinariya, kar a yi amfani da hanyar sanya HASL. This electroplated surface provides a better skin effect for high-frequency currents (Figure 2). In addition, this highly weldable coating requires fewer leads, helping to reduce environmental pollution.

8. Solder resistance layer can prevent solder paste from flowing. Koyaya, saboda rashin tabbas na kauri da aikin rufin da ba a sani ba, rufe dukkan farantin farantin tare da kayan juriya na siyarwa zai haifar da babban canji a cikin wutar lantarki a cikin ƙirar microstrip. Generally, solderdam is used as welding resistance layer.

Idan baku saba da waɗannan hanyoyin ba, tuntuɓi gogaggen injiniyan ƙira wanda yayi aiki akan allon kewaya microwave don sojoji. You can also discuss with them what price range you can afford. Misali, ya fi tattalin arziƙi yin amfani da ƙirar microstrip na Coplanar mai goyan bayan tagulla fiye da ƙirar tsiri, kuma kuna iya tattauna wannan tare da su don samun ingantacciyar shawara. Injiniyoyi masu kyau ba za su saba da yin tunani game da farashi ba, amma shawararsu na iya zama da taimako. Zai zama aiki na dogon lokaci don horar da ƙwararrun injiniyoyi waɗanda ba su saba da tasirin RF ba kuma ba su da ƙwarewa wajen magance tasirin RF.

Bugu da ƙari, ana iya karɓar wasu mafita, kamar haɓaka ƙirar kwamfuta don samun damar ɗaukar tasirin RF.

Haɗin PCB tare da na’urorin waje

Yanzu zamu iya ɗauka cewa mun warware duk matsalolin sarrafa siginar a kan jirgin da kan haɗin haɗin abubuwan da ke da ma’ana. Don haka ta yaya kuke warware matsalar shigar/fitowar siginar daga allon kewaye zuwa waya da ke haɗa na’urar nesa? TrompeterElectronics, mai ƙira a cikin fasahar kebul na coaxial, yana aiki akan wannan matsalar kuma ya sami ci gaba mai mahimmanci (adadi na 3). Also, take a look at the electromagnetic field shown in Figure 4 below. A wannan yanayin, muna sarrafa juyawa daga microstrip zuwa kebul na coaxial. A cikin igiyoyin coaxial, ana haɗa sassan ƙasa a cikin zobba kuma an daidaita su daidai. A cikin microbelts, layin ƙasa yana ƙasa da layin aiki. Wannan yana gabatar da wasu sakamako masu illa waɗanda ke buƙatar fahimta, annabta, da la’akari a lokacin ƙira. Tabbas, wannan rashin daidaituwa kuma yana iya haifar da koma baya kuma dole ne a rage shi don gujewa hayaniya da tsangwama na sigina.

Gudanar da matsalar rashin cikaswar ciki ba matsala ce ta ƙira da za a iya yin watsi da ita ba. The impedance starts at the surface of the circuit board, passes through a solder joint to the joint, and ends at the coaxial cable. Saboda rashin jituwa ya bambanta tare da mitar, mafi girman mita, mafi wahalar sarrafa rashin ƙarfi shine. The problem of using higher frequencies to transmit signals over broadband appears to be the main design problem.