1. Gabaɗaya dokoki
1.1 An riga an raba wuraren siginar dijital, analog da DAA akan PCB.
1.2 Na'urorin dijital da na analog da na'urorin da suka dace ya kamata a raba su gwargwadon yiwuwa kuma a sanya su a cikin wuraren nasu.
1.3 Alamun siginar dijital mai sauri ya kamata su kasance gajere gwargwadon yiwuwa.
1.4 Kiyaye alamun siginar analog gajarta gwargwadon yiwuwa.
1.5 Madaidaicin rarraba wutar lantarki da ƙasa.
1.6 DGND, AGND, da filin sun rabu.
1.7 Yi amfani da wayoyi masu faɗi don samar da wutar lantarki da alamun sigina masu mahimmanci.
1.8 Ana sanya da'irar dijital kusa da daidaitaccen bas/serial DTE interface, kuma ana sanya da'irar DAA kusa da layin wayar tarho.
2. Sanya sassa
2.1 A cikin tsarin tsarin da'ira:
a) Rarraba dijital, analog, DAA da da'irori masu alaƙa;
b) Rarraba dijital, analog, gauraye na'urorin dijital / analog a cikin kowane da'ira;
c) Kula da matsayi na samar da wutar lantarki da siginar siginar kowane guntu IC.
2.2 Tun da farko raba yankin wayoyi na dijital, analog, da da'irori na DAA akan PCB (gaba ɗaya rabo 2/1/1), da kiyaye abubuwan dijital da na analog da na'urorin da suka dace da nisa gwargwadon iko kuma iyakance su zuwa nasu. wuraren wayoyi.
Lura: Lokacin da da'irar DAA ta mamaye babban rabo, za a sami ƙarin alamun sarrafawa / matsayi na siginar da ke wucewa ta yankin wayar ta, wanda za'a iya daidaita shi bisa ga ƙa'idodin gida, kamar tazarar sassan, babban ƙarfin lantarki, iyakar halin yanzu, da dai sauransu.
2.3 Bayan an gama rabon farko, fara sanya abubuwan haɗin gwiwa da Jack:
a) Matsayin plug-in an tanada shi a kusa da Mai Haɗi da Jack;
b) Bar sarari don wutar lantarki da na'ura mai ba da hanya tsakanin hanyoyin sadarwa;
c) Ajiye matsayin filogi mai dacewa a kusa da Socket.
2.4 Wurin farko na abubuwan haɗin gwiwar (kamar na'urorin Modem, A/D, guntuwar jujjuyawar D/A, da sauransu):
a) Ƙayyade alkiblar abubuwan da aka haɗa, da ƙoƙarin sanya siginar dijital da fitilun siginar analog su fuskanci wuraren wayoyi daban-daban;
b) Sanya abubuwan da aka gyara a mahaɗin dijital da wuraren siginar analog.
2.5 Sanya duk na'urorin analog:
a) Sanya abubuwan da'irar analog, gami da da'irori na DAA;
b) Ana sanya na'urorin Analog kusa da juna kuma an sanya su a gefen PCB wanda ya haɗa da alamun TXA1, TXA2, RIN, VC, da VREF;
c) Ka guji sanya manyan abubuwan haɗin kai a kusa da alamun siginar TXA1, TXA2, RIN, VC, da VREF;
d) Don jerin abubuwan DTE, DTE EIA/TIA-232-E
Mai karɓa/direba na sigina na mu'amala ya kamata ya kasance kusa da mai haɗawa kuma nesa da babban siginar siginar agogo mai tsayi don rage / guje wa ƙarin na'urorin da za a hana surutu akan kowane layi, kamar su coils da capacitors.
2.6 Sanya abubuwan da aka gyara na dijital da masu haɓakawa:
a) Ana sanya sassan dijital tare don rage tsawon wayoyi;
b) Sanya 0.1uF decoupling capacitor tsakanin wutar lantarki da ƙasa na IC, kuma kiyaye wayoyi masu haɗawa a takaice kamar yadda zai yiwu don rage EMI;
c) Don nau'ikan bas masu kama da juna, abubuwan haɗin suna kusa da juna
Ana sanya mai haɗawa a gefen don biyan ma'aunin ƙirar bas ɗin aikace-aikacen, kamar tsayin layin bas ɗin ISA yana iyakance ga 2.5in;
d) Don serial DTE kayayyaki, da'irar dubawa yana kusa da Mai Haɗi;
e) Ya kamata kewayen oscillator crystal ya kasance kusa da na'urar tuƙi.
2.7 Wayoyin ƙasa na kowane yanki yawanci ana haɗa su a maki ɗaya ko fiye tare da 0 Ohm resistors ko beads.
3. Hanyar sigina
3.1 A cikin siginar siginar modem, layukan siginar da ke da saurin hayaniya da layukan siginar da ke da saurin tsangwama ya kamata a kiyaye su nesa ba kusa ba.Idan ba zai yuwu ba, yi amfani da layin siginar tsaka tsaki don ware.
3.2 Ya kamata a sanya siginar siginar dijital a cikin yankin siginar siginar kamar yadda zai yiwu;
Ya kamata a sanya siginar siginar siginar a cikin yankin siginar siginar analog gwargwadon yiwuwa;
(Za a iya sanya alamun keɓewa don iyakancewa don hana alamun fita daga yankin da ake tuƙi)
Alamomin sigina na dijital da alamun siginar analog suna kan layi don rage haɗin haɗin gwiwa.
3.3 Yi amfani da keɓantattun alamomi (yawanci ƙasa) don ƙetare alamun siginar analog zuwa yankin siginar analog.
a) An shirya wuraren keɓewar ƙasa a cikin yankin analog a bangarorin biyu na allon PCB a kusa da yankin siginar siginar analog, tare da faɗin layin 50-100mil;
b) Ana zazzage alamun ƙasa mai keɓance a cikin yanki na dijital a kusa da yankin siginar dijital a bangarorin biyu na allon PCB, tare da faɗin layin 50-100mil, kuma faɗin gefe ɗaya na kwamitin PCB ya zama 200mil.
3.4 Siginar siginar siginar siginar layi ɗaya daidai> 10mil (gaba ɗaya 12-15mil), kamar /HCS, /HRD, /HWT,/Sake saiti.
3.5 Nisa layin alamun siginar analog shine> 10mil (gaba ɗaya 12-15mil), kamar MICM, MICV, SPKV, VC, VREF, TXA1, TXA2, RXA, TELIN, TELOUT.
3.6 Duk sauran alamun siginar ya kamata su kasance mai faɗi kamar yadda zai yiwu, faɗin layin ya zama> 5mil (mil 10 gabaɗaya), kuma alamun da ke tsakanin abubuwan ya kamata su kasance gajere gwargwadon yiwuwa ( yakamata a yi la'akari da lokacin sanya na'urori).
3.7 Layin layi na capacitor na kewayawa zuwa daidaitaccen IC ya kamata ya zama> 25mil, kuma ya kamata a guji yin amfani da ta hanyar iyawa. wuce ta keɓaɓɓen wayoyi na ƙasa a wuri ɗaya (wanda aka fi so) ko maki biyu.Idan alamar ta kasance a gefe ɗaya kawai, keɓewar alamar ƙasa na iya zuwa wancan gefen PCB don tsallake alamar siginar kuma ci gaba da shi.
3.9 Ka guji amfani da sasanninta na digiri 90 don babban mitar sigina, kuma amfani da santsi mai santsi ko kusurwoyi 45-digiri.
3.10 Babban mitar sigina ya kamata ya rage amfani da hanyar haɗi.
3.11 Kiyaye duk alamun sigina daga da'irar oscillator crystal.
3.12 Don isar da sigina mai girma, yakamata a yi amfani da tuƙi guda ɗaya mai ci gaba don guje wa yanayin da sassan da dama suka shimfiɗa daga wuri ɗaya.
3.13 A cikin da'irar DAA, bar sarari na akalla 60mil a kusa da perforation (duk yadudduka).
4. Wutar lantarki
4.1 Ƙayyade dangantakar haɗin wutar lantarki.
4.2 A cikin yanki na siginar dijital, yi amfani da capacitor 10uF electrolytic capacitor ko tantalum capacitor a layi daya tare da yumbu capacitor na 0.1uF sannan ka haɗa shi tsakanin wutar lantarki da ƙasa.Sanya ɗaya a ƙarshen mashigan wutar lantarki da mafi nisa ƙarshen allon PCB don hana tsangwama da tsangwama da hayaniya ke haifarwa.
4.3 Don allunan gefe biyu, a cikin nau'in nau'in nau'in nau'in wutar lantarki, kewaye da kewaye tare da alamun wutar lantarki tare da fadin layi na 200mil a bangarorin biyu.(Dole ne a sarrafa ɗayan ɓangaren ta hanyar daidai da ƙasa na dijital)
4.4 Gabaɗaya, ana fara shimfida alamun wutar lantarki, sannan kuma ana shimfida alamun siginar.
5. kasa
5.1 A cikin allo mai gefe biyu, wuraren da ba a yi amfani da su ba a kusa da ƙasa da na'urorin dijital da na analog (sai dai DAA) suna cike da dijital ko analog, kuma an haɗa nau'o'i iri ɗaya na kowane Layer tare, kuma wurare iri ɗaya na yadudduka daban-daban. an haɗa ta ta hanyar da yawa: Modem DGND fil an haɗa shi zuwa yankin ƙasa na dijital, kuma an haɗa fil ɗin AGND zuwa yankin ƙasa na analog;yankin ƙasa na dijital da yankin ƙasa na analog an raba su da madaidaiciyar rata.
5.2 A cikin allo mai layi huɗu, yi amfani da wuraren ƙasa na dijital da analog don rufe abubuwan dijital da analog (sai dai DAA);an haɗa fil ɗin DGND na Modem zuwa yankin ƙasa na dijital, kuma an haɗa fil ɗin AGND zuwa yankin ƙasa na analog;ana amfani da yankin ƙasa na dijital da yanki na analog ɗin da aka raba ta madaidaiciyar rata.
5.3 Idan ana buƙatar tacewa na EMI a cikin ƙira, ya kamata a tanadi wani wuri a soket ɗin mu'amala.Yawancin na'urorin EMI (beads / capacitors) ana iya sanya su a wannan yanki;hade da shi.
5.4 Ya kamata a raba wutar lantarki na kowane tsarin aiki.Za'a iya raba na'urori masu aiki zuwa: layin bas na layi daya, nuni, da'ira na dijital (SRAM, EPROM, Modem) da DAA, da dai sauransu. Za'a iya haɗa wutar lantarki/ƙasa na kowane nau'in kayan aiki kawai a tushen wuta / ƙasa.
5.5 Domin serial DTE modules, yi amfani da decoupling capacitors don rage wutar lantarki, kuma yi haka don layukan tarho.
5.6 An haɗa wayar ƙasa ta hanyar aya ɗaya, idan zai yiwu, yi amfani da Bead;idan ya zama dole don murkushe EMI, ba da damar haɗa waya ta ƙasa a wasu wurare.
5.7 Duk wayoyi na ƙasa yakamata su kasance da faɗi sosai gwargwadon yiwuwa, mil 25-50.
5.8 Alamar capacitor tsakanin duk wutar lantarki / ƙasa na IC ya kamata ya zama gajere kamar yadda zai yiwu, kuma babu ta hanyar ramuka yakamata a yi amfani da shi.
6. Crystal oscillator kewaye
6.1 Duk alamun da aka haɗa zuwa tashar shigarwa / fitarwa na oscillator crystal (kamar XTLI, XTLO) yakamata su kasance gajere gwargwadon yuwuwa don rage tasirin tsangwama a cikin hayaniya da rarraba capacitance akan Crystal.Alamar XTLO yakamata ta zama gajere gwargwadon yuwuwa, kuma kusurwar lanƙwasawa kada ta kasance ƙasa da digiri 45.(Saboda an haɗa XTLO zuwa direba mai saurin tashi lokaci da babban halin yanzu)
6.2 Babu wani Layer na ƙasa a cikin jirgi mai gefe biyu, kuma ya kamata a haɗa waya ta ƙasa na capacitor crystal oscillator zuwa na'urar tare da gajeren waya kamar yadda zai yiwu.
Fitin DGND mafi kusa da oscillator crystal, kuma rage yawan ta hanyar.
6.3 Idan za ta yiwu, yi ƙasa al'amarin crystal.
6.4 Haɗa resistor 100 Ohm tsakanin fil ɗin XTLO da kullin crystal/ capacitor.
6.5 Ƙasa na capacitor oscillator kristal ana haɗa kai tsaye zuwa fil ɗin GND na Modem.Kada kayi amfani da yankin ƙasa ko alamar ƙasa don haɗa capacitor zuwa fil ɗin GND na Modem.
7. Tsarin Modem mai zaman kanta ta amfani da EIA/TIA-232 dubawa
7.1 Yi amfani da akwati na karfe.Idan ana buƙatar harsashi na filastik, a liƙa foil ɗin ƙarfe a ciki ko kuma a fesa kayan aiki don rage EMI.
7.2 Sanya Chokes na tsari iri ɗaya akan kowace igiyar wuta.
7.3 Abubuwan da aka haɗa an haɗa su tare kuma kusa da Mai Haɗi na ƙirar EIA/TIA-232.
7.4 Duk na'urorin EIA/TIA-232 an haɗa su daban-daban zuwa wuta/ƙasa daga tushen wutar lantarki.Tushen wutan lantarki ya kamata ya zama tashar shigar da wutar lantarki a kan allo ko kuma tashar fitarwa na guntu mai sarrafa wutar lantarki.
7.5 EIA/TIA-232 siginar kebul na ƙasa zuwa ƙasan dijital.
7.6 A cikin waɗannan lokuta, garkuwar USB EIA/TIA-232 baya buƙatar haɗawa da harsashi na Modem;haɗin komai;an haɗa shi da ƙasan dijital ta hanyar katako;Ana haɗa kebul ɗin EIA/TIA-232 kai tsaye zuwa ƙasan dijital lokacin da aka sanya zoben maganadisu kusa da harsashi na Modem.
8. Wiring na VC da VREF kewaye capacitors ya kamata ya zama takaice kamar yadda zai yiwu kuma yana cikin yankin tsaka tsaki.
8.1 Haɗa tabbataccen tasha na 10uF VC electrolytic capacitor da 0.1uF VC capacitor zuwa VC fil (PIN24) na Modem ta wata waya daban.
8.2 Haɗa mummunan tasha na 10uF VC electrolytic capacitor da 0.1uF VC capacitor zuwa AGND fil (PIN34) na Modem ta hanyar Bead kuma yi amfani da waya mai zaman kanta.
8.3 Haɗa ingantaccen tasha na 10uF VREF electrolytic capacitor da 0.1uF VC capacitor zuwa VREF fil (PIN25) na Modem ta wata waya daban.
8.4 Haɗa mummunan tasha na 10uF VREF electrolytic capacitor da 0.1uF VC capacitor zuwa VC fil (PIN24) na Modem ta hanyar alama mai zaman kanta;lura cewa yana da zaman kanta daga alamar 8.1.
VREF ——+——–+
10 ku 0.1u
VC ——————
10 ku 0.1u
+——–+—–~~~~~—+ AGND
Bead da aka yi amfani da shi ya kamata ya hadu:
Impedance = 70W a 100MHz;;
rated halin yanzu = 200mA;;
Matsakaicin juriya = 0.5W.
9. Waya da Handset interface
9.1 Sanya Choke a mahaɗin tsakanin Tip da Ring.
9.2 Hanyar yankewar layin wayar yayi kama da na wutar lantarki, ta amfani da hanyoyi kamar ƙara haɗin inductance, shake, da capacitor.Duk da haka, ƙaddamar da layin wayar ya fi wuya kuma ya fi dacewa fiye da ƙaddamar da wutar lantarki.Babban aikin shine a tanadi wuraren waɗannan na'urori don daidaitawa yayin takaddun gwajin aiki/EMI.
Lokacin aikawa: Mayu-11-2023