Dab tsi yog Cov Ntsiab Cai thiab Kev Siv Tus PIN Diodes? (Part 2)

Ib qho diode feem ntau muaj PN kev sib tshuam. Tus PIN diode yog tus PIN diode los ntawm kev ntxiv txheej nyias ntawm cov khoom siv qis-doping Intrinsic semiconductor ntawm P thiab N semiconductor cov ntaub ntawv. Vim tias muaj cov txheej txheem Intrinsic, PIN diodes tau siv dav, los ntawm cov zaus tsawg mus rau cov ntawv thov siab, feem ntau yog siv hauv RF teb, xws li RF keyboards thiab RF tiv thaiv circuits, thiab kuj siv los ua photodiodes. PIN diode suav nrog PIN photodiode thiab PIN hloov diode.Noj part 1.

3. PIN diode li RF hloov

① Lub hauv paus ntsiab lus ua haujlwm

Vim hais tias RF tsis kam ntawm tus PIN diode muaj feem xyuam rau DC bias tam sim no, nws tuaj yeem siv los ua RF hloov thiab attenuator. Series RF hloov hluav taws xob: thaum lub diode yog qhov zoo, nws tau hloov mus rau (luv luv luv); Thaum lub diode yog xoom-biased los yog thim rov qab-biased, bandwidth tuaj yeem hloov pauv: tsis yog qhov kev ua haujlwm siab tshaj plaws ntawm kev hloov pauv yuav raug txwv, tab sis kuj yuav txo qis kev khiav hauj lwm zaus, xws li PIN raj tsis tuaj yeem tswj cov on-off ntawm DC los yog tsawg-frequency signals. Qhov hloov pauv kuj muaj qhov ua haujlwm siab tshaj plaws, uas cuam tshuam los ntawm kev txiav tawm zaus ntawm lub raj. Qhov zaus ntawm qhov hloov pauv yuav tsum tau ua kom dav raws li qhov ua tau ① vim tias qhov zaus band ntawm lub teeb liab tau txais dav thiab dav.

② Kev ua haujlwm tsis zoo

Insertion poob thiab kev rho tawm: Insertion attenuation yog txhais raws li lub siab tshaj plaws muaj hwj chim P generated los ntawm lub teeb liab qhov chaw.

Qhov sib piv ntawm lub zog tiag tiag P rau qhov khoom tau txais thaum qhov hloov pauv, uas yog, P / P. Yog tias lub zog tiag tiag ntawm lub nra thaum lub qhov hloov pauv yog P, nws sawv cev rau kev sib cais, sau rau hauv daim ntawv ntawm decibels:

Raws li lub ntsiab txhais ntawm network scattering parameters, muaj:

Rau qhov zoo tagnrho hloov:lub attenuation yog infinite thaum nws yog disconnected, lub attenuation yog xoom thaum nws yog switched, thiab qhov ratio ntawm ob feem ntau tsuas yog yuav tsum tau kom loj npaum li cas. Txij li thaum lub impedance ntawm tus PIN raj tsis tuaj yeem txo mus rau xoom, thiab tsis tuaj yeem nce mus rau qhov kawg, qhov hloov pauv tiag tiag tsis muaj qhov tsis txaus ntseeg thaum nws raug rho tawm, thiab nws tsis yog xoom thaum nws hloov mus, feem ntau tsuas yog qhov piv. ntawm ob qhov yuav tsum loj npaum li qhov ua tau, qhov hloov pauv ntawm qhov kev tawm ntawm qhov attenuation yog hu ua insertion poob, thiab lub attenuation thaum nws raug rho tawm yog hu ua kev rho tawm, qhov poob thiab kev rho tawm yog qhov qhia tau yooj yim ntawm kev ntsuas qhov zoo ntawm qhov hloov. Lub hom phiaj yog los tsim cov keyboards uas tsis tshua muaj qhov poob qis thiab kev sib cais siab.

Lub zog muaj peev xwm:Lub zog muaj peev xwm ntawm qhov hloov pauv yog hais txog qhov siab tshaj plaws lub zog microwave nws tuaj yeem tiv taus. Lub zog muaj peev xwm ntawm tus PIN diode feem ntau yog txwv los ntawm ob yam hauv qab no: qhov siab tshaj plaws siv hluav taws xob tau tso cai thaum lub raj hloov pauv; Qhov siab tshaj qhov rov qab voltage uas lub raj tuaj yeem tiv taus thaum nws raug txiav tawm, uas yog, qhov rov qab tawg voltage. Yog tias qhov hloov pauv dhau qhov kev txwv no thaum ua haujlwm, qhov qub yuav ua rau qhov kub thiab txias hauv lub raj kom siab dhau thiab kub hnyiab; Qhov tom kawg yuav ua rau muaj kev puas tsuaj hauv cheeb tsam I. Nws yog txiav txim los ntawm lub zog hluav taws xob me me uas tso cai rau hauv lub xeev ntawm kev hloov pauv. Cov teebmeem nonlinear ntawm lub zog siab (IIP3

Nws kuj yog ib qho tseem ceeb ntawm lub zog ntawm kev hloov, tshwj xeeb tshaj yog nyob rau hauv kev sib txuas lus hauv paus chaw nres tsheb.

Cov Kev Cai Tsav Tsheb: Tus tsav tsheb Circuit Court ntawm PI N raj hloov thiab FET hloov pauv yog qhov sib txawv, qhov qub yuav tsum tau muab kev tsis ncaj ncees tam sim no, tom kawg yuav tsum muaj kev tsis ncaj ncees, tus tsav tsheb yog qhov zoo lossis qhov tsis zoo yog ib qho tseem ceeb cuam tshuam rau kev hloov ceev.

Switching ceev: yog hais txog qhov ceev ntawm switching on thiab off, uas yog ib qho tseem ceeb qhia nyob rau hauv cov khoom siv ceev ceev. Qhov kev sib npaug tam sim no hauv cheeb tsam kuv tuaj yeem teev npe raws li hauv qab no:

Hloov ceevyog nce mus rau qhov kev txiav txim ntawm ns, feem ntau yog siv ib tug PIN raj nrog ib tug nyias txheej kuv, vim hais tias tus naj npawb ntawm cov cab kuj khaws cia nyob rau hauv lub nyias txheej kuv yog me me, thiab lub sij hawm hloov yog shortened heev, nyob rau hauv cov ntaub ntawv no, lub sij hawm hloov pib. nyob ntawm tus neeg nqa khoom hla lub sijhawm kuv txheej, thiab tsis muaj dab tsi cuam tshuam nrog tus neeg nqa khoom lub neej. Txhawm rau txhim kho qhov hloov pauv ceev, cov yeeb nkab nrog lub neej luv luv kuj tuaj yeem raug xaiv los ua kom cov mem tes amplitude ntawm kev tswj tam sim no, tab sis tom kawg yog txwv los ntawm lub zog siab tshaj plaws ntawm PIN raj thiab qhov rov qab tawg voltage.

Voltage sawv wave ratio (VSWR):Ib qho kev tivthaiv ntawm lub high-frequency teeb liab channel yuav tsis tsuas yog ua rau kev nkag tsis tau tab sis kuj ua rau muaj kev nce nyob rau hauv sawv nthwv dej ntawm cov teeb liab kis kab mob. Cov nthwv dej sawv ntsug yog tsim los ntawm kev cuam tshuam ntawm kev sib kis thiab cuam tshuam cov hluav taws xob tsis sib xws, uas feem ntau tshwm sim los ntawm impedance tsis sib haum nyob rau hauv ntau qhov chaw ntawm lub cev lossis impedance tsis sib haum ntawm cov ntsiab lus sib txuas hauv lub cev.

Switching ratio:Thaum lub raj PIN tsis xav txog cov kab mob parasitic ntawm pob, nws lub xeev pem hauv ntej tuaj yeem qhia tau los ntawm kev tawm tsam R1, thiab lub xeev rov qab tuaj yeem qhia tau los ntawm kev rov qab series tsis kam R2 thiab I-txheej capacitive reactance jXc, hauv series. . Vim > R2, yog li lub xeev rov qab tuaj yeem kwv yees los ntawm jXc, peb hu qhov piv ntawm qhov zoo thiab qhov tsis zoo ntawm ob lub xeev Xc / R1 raws li qhov hloov pauv, ntsuas qhov zoo thiab qhov tsis zoo ntawm tus PIN hloov. Yog tias qhov hloov pauv yuav tsum tau nce, ces C thiab R2 yuav tsum yog me me, thiab nws tuaj yeem pom tias qhov kev hloov pauv tau txo qis thaum qhov zaus nce.

Cov ntaub ntawv tiv tauj:

Yog tias koj muaj lus nug, thov hu rau peb. Txawm peb cov neeg muas zaub nyob qhov twg thiab peb cov kev xav tau yog dab tsi, peb yuav ua raws li peb lub hom phiaj los muab peb cov neeg siv khoom zoo, tus nqi qis, thiab kev pabcuam zoo tshaj plaws.