Maitiro eDielectric Constant & Loss Tangent Anobata High Frequency PCB Performance

ziviso

Kushanda kwemagadzirirwo ePCB ane frequency yakakwira kunoenderana zvakanyanya nehunhu hwezvinhu zve substrate kwete circuit topology chete. Sezvo mafrequency ekushanda achifambira mberi kupfuura 1 GHz, maitiro emagetsi ezvinhu zve dielectric anova chinhu chikuru chinosarudza kana masaini achichengetedza hunhu hwawo kubva kune transmitter kuenda kune receiver. Hunhu huviri hwezvinhu hunodzora maitiro aya: dielectric constant uye loss tangent.

Dielectric inogara inodzora kumhanya uko mafungu emagetsi anopararira kuburikidza neiyo substrate, inokanganisa zvakananga nguva yechiratidzo uye mutsara wekutapurirana impedance. Kurasika tangent kunotara kuti ingani simba rechiratidzo rinoparara sekupisa kwete kusvika kwarinosvika. Kunzwisisa kuti maparamendi aya anodyidzana sei kunoita kuti mainjiniya afanotaura kuderedzwa kwechiratidzo, kudzora impedance nenzira kwayo, uye kusarudza zvinhu zvinosangana nezvinodiwa frequency nekuyeresa mutengo uye zvipingaidzo zvekugadzira.

Kunzwisisa Dielectric Constant (Dk) uye Basa Rayo

Zvinorehwa neDielectric Constant yeSiginecha Propagation

Dielectric nguva dzose inoyera kugona kwechinhu kuchengetedza simba remagetsi kana yaiswa pamunda wemagetsi, inoratidzwa maererano ne vacuum. Ichi chakakosha chivakwa chinotemesa chiratidzo chekuparadzira velocity zvinoenderana nehukama v = c / √Dk, uko yakaderera dielectric inongogara tsika inobvumira kukurumidza kwechiratidzo kufamba. Iko kukosha kunoshanda kunobuda pachena mukutora nguva-yakakosha yakakwira frequency PCB maapplication uko nanosecond-level kunyatsoita basa.

Typical Dk Values ​​Pakati peZvinhu

Zvakajairwa substrate zvinhu zvinotambanudzira dielectric inogara renji iyo inokanganisa zvakanyanya dhizaini sarudzo:

• Standard FR4 - Dk kukosha pakati pe4.2 uye 4.8 pa 1 GHz, yakakodzera kune zvakajairwa-chinangwa maapplication.
• laminate yakakosha ine kurasikirwa kwakaderera, laminate yakakosha ine kurasikirwa kwakaderera - Inodzorwa Dk yakatenderedza 3.48, ichipa kushivirira kwakasimba kweRF maseketi.
• PTFE-based substrates - Dk zvakaderera se 2.2, ichigonesa kumhanya kwepamusoro kwekuparadzira kwekushandisa microwave.

Dk Uniformity uye Impedance Kudzora

Consistency mune dielectric yenguva dzose mukati meiyo substrate ukobvu uye planar zviyero zvinotemesa impedance kutonga kurongeka mune yakakwirira frequency PCB dhizaini. Kugadzira misiyano ye 0.1 chete muDk inoturikira kune akati wandei ohms ekuchinja kwe impedance mu50-ohm kutapurirana mitsara, zvichigona kukonzera ratidziro inodzikisira kunaka kwechiratidzo. Material anisotropy, apo Dk anosiyana pakati pezvakarongwa uye zvakati sandara zvinomisikidzwa, zvinowedzera kuoma kunoda muripo mukuronga kwakarongeka.

Kunzwisisa Kurasika Tangent (Df kana Tan δ)

Kutsanangura Dielectric Kurasika

Kurasika tangent inomiririra reshiyo yesimba rakaraswa sekupisa kune simba rakachengetwa mudielectric panguva yega yega electromagnetic cycle. Nemasvomhu inoratidzwa senge tangent yekona yekurasika, iyi parameter inoratidza kuti ndechipi chikamu chesimba rechiratidzo chinoshandura kusimba rinopisa pane kuparadzira munzira inodiwa. Kurasikirwa kwakaderera tangent kukosha kunoenderana zvakananga nekuderedzwa kwechiratidzo kuderedzwa uye yepamusoro yepamusoro frequency PCB kuita.

Material Loss Tangent Kuenzanisa

Kurasika kwezvinhu tangent kunotenderera kwakasiyana-siyana pane zviripo substrate sarudzo:

• FR4 - Df pakati pe0.020 ne0.025, ichidzikamisa kushandiswa kunoshanda kune ma frequency ari pasi pe3 GHz.
• laminate yakakosha ine kurasikirwa kwakaderera, laminate yakakosha ine kurasikirwa kwakaderera - Df ingangoita 0.0037, ichiwedzera kushanda kune 10 GHz uye kupfuura.
• PTFE-based laminates - Df kubva pa0.001 kusvika 0.002, inotsigira maapplication anosvika makumi mana GHz ane kushoma attenuation.

Frequency-Dependent Loss Effects

Kukanganisa kwekurasikirwa tangent kunowedzera sezvo frequency inowedzera nekuti dielectric kurasikirwa zviyero zvakaenzanirana neanoshanda frequency. Pa 10 GHz, chinhu chine Df ye0.020 chinosuma chingangoita 1-2 dB yekuwedzera kurasikirwa kwekuisa pa inch kana zvichienzaniswa nezvinhu zvine Df ye0.004. Zvinhu zvakatipoteredza zvinokanganisawo kurasikirwa tangent kugadzikana, neFR4 substrates inosangana neDf inowedzera ye20-30% pasi pekuratidzwa kwehunyoro hwepamusoro nepo hydrophobic zvinhu sePTFE inochengetedza kuita kwakafanana.

Sei Dk uye Df Pamwe Vanopesvedzera Yakakwira Frequency PCB Kuita

Chiratidzo Kuperera

Yakakwirira dielectric inogara ichikosha inowedzera capacitive coupling pakati pematanho ari padyo, inosimudzira crosstalk susceptibility mune densely raid yakakwirira frequency PCB marongero. Iyo yakaderedzwa yekuparadzira velocity yakabatana neakakwira Dk inogadzira nguva skew apo masaini anotenderera matunhu ane akasiyana anoshanda dielectric constants. Kurasika tangent kunotonga zvakananga kuchengetedzwa kwechiratidzo cheamplitude, ine yakakwira Df kukosha inokonzera kuderera kunoderedza kuzungunuka kwevoltage uye kupfupisa kuvhurwa kwedhiyagiramu yeziso.

Impedance Kudzora uye Dhizaini Kushivirira

Kugadzira misiyano mune dielectric inogara ichishandura yakananga kune impedance kushivirira siyana. Yakajairwa ± 0.1 Dk kusiyanisa mune yakajairwa FR4 inoburitsa ingangoita ±2 kusvika 3 ohms ye impedance kutsauka kwe50-ohm microstrip mitsetse. Electromagnetic simulation maturusi akadai sePolar SI9000 uye Ansys HFSS inosanganisa ese dielectric kugara uye kurasikirwa tangent kufanotaura maitiro ekutapurirana nenzira kwayo, zvichiratidza kuti kushivirira kwaDk kunokanganisa sei kugadzikana uku Df ichisarudza kupinza kurasikirwa mutsetse ne frequency.

Kupera Simba uye Kupisa Kupisa

Dielectric kurasikirwa inoshandura simba reRF kuita simba rinopisa mukati meiyo substrate, ichisimudza tembiricha yejoinhi muzvikamu zvinoshanda. Iyo yakakwira frequency PCB inoshanda pa5 GHz ine Df ye0.020 inogona kuburitsa akati wandei mawatts paskweya inch munzvimbo dzine migwagwa mizhinji, zvichienzaniswa isingasviki watt imwe yezvinhu zvine Df pazasi 0.005. RF simba amplifiers uye transmitter nhanho inowana yakanyanya kubhenefiti kubva kune yakaderera kurasikirwa tangent zvinhu nekuti dielectric kudziyisa kunoitika chaizvo uko kupisa kwekutonga kunoratidza kuoma zvakanyanya.

Kusarudzwa kwezvinhu uye Kugadzirwa

Kuenzanisa zvinodiwa zvemagetsi nezvinodiwa zvehupfumi kunoda kuenzanisa kugona kwezvinhu zvinoenderana nezvinodiwa nemafrequency chaiwo. FR4 inoshanda zvakakwana kune zvishandiso zviri pasi pe3 GHz, zvinhu zvepakati-tier zvakaita se specialty low-loss laminate specialty low-loss laminate inopa kugadzikana kunoshanda kwemagadzirirwo e5-10 GHz, nepo PTFE-based substrates ichidikanwa kana mafrequency adarika 20 GHz. Kunyudzwa kwehunyoro kunokanganisa kugadzikana kwe dielectric constant uye kurasikirwa, neFR4 ichinyudzwa kusvika ku0.15% hunyoro nehuremu zvichienzaniswa nepasi pe0.02% ye PTFE-based laminate.

Material Kuenzanisa kweHigh Frequency Applications

Kuenzanisa uku kunoratidza maitiro ekuita anowanikwa kune yakakwira frequency PCB maapplication pane akasiyana ekushanda frequency renji. Sarudzo yemidziyo inofanirwa kunanga hudiki hwekuita nhanho inogutsa zvikumbiro zvekushandisa uku uchiona akakwana emagetsi magini echiratidzo chekuvimbika uye impedance control.

Mazano Anoshanda ePCB Vagadziri

Shandisa Real Material Parameters

Vagadziri vanofanirwa kuburitsa chaiyo dielectric inogara uye kurasikirwa tangent kukosha kubva kuzvinhu zvinyorwa pane chaiyo frequency uye tembiricha mamiriro ane chekuita nekushandisa kwavo kwete kuvimba neakajairwa hunhu. Mazhinji madhetabheti anopa frequency-inotsamira macurves anoratidza kusiyanisa kweparameter mukati mese inoshanda spectrum, iyo inovandudza zvakanyanya electromagnetic simulation kurongeka kwebroadband high frequency PCB dhizaini inotora akawanda frequency makumi emakore.

Funga nezve Frequency Dependence

Ose ari maviri dielectric anogara uye kurasikirwa tangent anosiyana ne frequency. Dielectric nguva dzose inodzikira zvishoma nekuwedzera frequency apo kurasikirwa tangent kunogona kuwedzera. Vagadziri vanoshanda ne-ultra-wideband application kana ma-harmonic-rich masiginecha anofanirwa kuzvidavirira kune aya ma frequency-anotsamira maitiro kuti achengetedze mashandiro mukati mese spectrum.

Dzivisa Mixed Dielectric Stackups

Kudzivirira akasanganiswa dielectric stackups pese pazvinoita zvinoderedza impedance discontinuities pane layer shanduko inoburitsa maratidziro. Kana zvinhu zvakasiyana zvichiratidza kuti zvinodikanwa, sekubatanidza yakaderera-kurasikirwa kweRF maseketi ane inodhura-inoshanda dhijitari dhizaini, nekuchenjerera shanduko dhizaini uye kuburikidza ne stub manejimendi kuderedza discontinuity mhedzisiro mune yakakwirira frequency PCB application.

Optimize Copper uye Prepreg Sarudzo

Kutsanangura yakaderera-kurasikirwa prepreg zvinhu uye yakaderera-mbiri-yemhangura foils inowedzera kuderedza kuzara kwekuisa kurasikirwa:

• Low-kurasikirwa prepreg -Inoderedza kurasikirwa kwedielectric mu multilayer stackups uko prepreg inosanganisira yakakura substrate vhoriyamu.
• Mhangura yakapfava -Inoderedza kurasikirwa kwekondukita kubva paganda roughness pamusoro pe10 GHz.
• Kudyidzana nevagadziri -Inoita shuwa inogoneka impedance kushivirira uye yechokwadi Dk kutonga miganho.

Nekunyatso kuenzanisa kushata kwemhangura uye prepreg dielectric zvivakwa, vagadziri vanogona kuwana yakagadzikana impedance uye kudzikisa kuderedzwa kwechiratidzo mukati mehupamhi frequency renji. Kugadziriswa kwezvinhu zvakadaro kwakakosha pakuita kuti ive nechokwadi chekushanda kwePCB inowirirana mukuda RF uye yakakwirira-kumhanya madhijitari.

mhedziso

Dielectric inogara ichidzora chiratidzo chekuparadzira velocity uye hunhu impedance mukati meyakanyanya frequency PCB dhizaini, nepo kurasikirwa tangent kunoteya kupera simba uye chiratidzo chekudzivirira panguva yekufambisa. Izvi zviviri zvezvinhu zvivakwa zvinoshanda zvakabatana kutsanangura zvinogoneka kuita kweRF maseketi, microwave masisitimu, uye yakakwirira-kumhanya yedhijitari interfaces inoshanda pa-multi-gigahertz frequencies.

Highleap Electronics Yakakwira Frequency PCB Kugona

KuHighleap Electronics, tinogadzira maPCB akagadzirwa nemazvo nehunyanzvi hwakakwana hwezvinhu:

• Zvinyorwa zvepamusoro - laminate yakasarudzika ine low-loss, Taconic, uye Megtron series laminates ine controlled Dr uye low Df specifications.
• Kudzora impedance -Tight kushivirira impedance kudzora nekusimbisa kuburikidza neTDR uye VNA kuyedzwa.
• Injiniya rutsigiro -Nhungamiro yekusarudza zvinhu, stackup optimization, uye dhizaini kusimbiswa kwechiratidzo chekutendeka.
• Process kunaka -Kusimba kwekugadzira kudzora kuvimbisa kugadzikana kushanda kwemagetsi mukati mehuwandu hwekugadzira.

Bata timu yedu yeinjiniya kuti tikurukure yako yakakwira frequency PCB zvinodiwa uye uwane maitiro atingaite optimize yako RF uye microwave madhizaini ekuita kwepamusoro.