Crystal oscillators - feem ntau hu ua crystals - yog siv dav hauv cov khoom siv hluav taws xob hauv hluav taws xob, feem ntau ua haujlwm los tsim cov cim kev siv cov zaus. Txawm hais tias siv lead ua oscillator muaj qhov zoo thiab qhov tsis zoo polarity tsis yog cov lus nug uas tuaj yeem teb tau yooj yim "yog" lossis "tsis yog"; nws nyob ntawm hom tshwj xeeb ntawm cov cuab yeej hauv nqe lus nug.
1. Passive Crystals (Crystal Resonators)
Passive crystals, tseem hu ua crystal resonators, uatsis yogmuaj qhov zoo lossis tsis zoo polarity. Lawv cov qauv sab hauv muaj xws li quartz siv lead ua dawb paug, ib lub voj voog resonant, thiab ib lub tsev nyob. Los ntawm qhov xwm txheej, lawv yog cov khoom siv passive thiab tsis muaj cov khoom siv hluav taws xob ua kom muaj zog. Nyob rau hauv cov qauv no, lub quartz siv lead ua ua raws li ib tug piezoelectric resonant caij uas generates lub ntuj vibration zaus; lub resonant circuit zoo -tunes thiab stabilizes zaus; thiab lub pob muab kev tiv thaiv txhua yam thiab hluav taws xob rwb thaiv tsev.
Vim hais tias ob lub teeb liab pins ntawm ib tug passive siv lead ua yog lub cev symmetrical thiab hluav taws xob sib npaug, tsis muaj kev taw qhia yuav tsum tau thaum lub sij hawm installation - ob lub pins yuav interchanged. Hauv kev tsim hluav taws xob, nws tsuas yog tsim nyog los txuas cov pins zaus mus rau oscillator input thiab output terminals ntawm IC thiab kom phim cov khoom tsim nyog load capacitors.
2. Active Crystals (Crystal Oscillators)
Active muaju, piv txwv li, tag nrho cov siv lead ua oscillator modules, muaj ib tug meej polarity yuav tsum tau (lub hwj chim mov polarity). Ntxiv nrog rau cov quartz siv lead ua, lawv nyob hauv kev sib koom ua ke ntawm lub oscillation Circuit Court thiab cov khoom tso tawm tsis muaj suab nrov, thiab yog li xav tau lub zog DC sab nraud los ua haujlwm.
Yog li ntawd, tus pin txhais ntawm cov siv lead ua muaj zog suav nrog lub hwj chim mov tus pin (VDD) thiab tus pin hauv av (GND), uas muaj qhov sib txawv nruj thiab yuav tsum tsis txhob thim rov qab. Pin assignments thiab marking conventions yuav txawv ntawm txawv qauv thiab manufacturers; qhov tseeb polarity thiab tus pin configuration yuav tsum yeej ib txwm raug txheeb xyuas tawm tsam cov khoom datasheet. Nws yog ib qho tseem ceeb kom paub meej txog cov kev sib txuas ua ntej lub hwj chim -txog kom tsis txhob muaj kev puas tsuaj ntawm cov cuab yeej lossis kev ua haujlwm tsis zoo vim yog qhov rov qab polarity.
Xaus
Hauv cov ntsiab lus, seb lub siv lead ua oscillator puas muaj qhov zoo thiab qhov tsis zoo ntawm qhov zoo yog nyob ntawm nws hom: passive crystals tsis yog -polarized, nrog ob lub teeb liab pins yog hluav taws xob sib npaug; active siv lead ua, txawm li cas los xij, muaj lub zog siv hluav taws xob polarity thiab yuav tsum tau txuas nrog nruj me ntsis raws li tus pinout specifications. Hauv cov ntawv thov kev tsim vaj tsev, kev tsim hluav taws xob tsim nyog thiab kev siv vuam yuav tsum tau ua raws li hom tshwj xeeb ntawm cov siv lead ua uas tau xaiv thiab nws cov ntaub ntawv yuav tsum tau ua, ua kom ntseeg tau thiab ruaj khov ntawm lub moos. Kev nkag siab zoo ntawm cov yam ntxwv hluav taws xob ntawm ntau yam siv lead ua oscillators kuj ua rau kom ua tiav kev ua haujlwm zoo hauv kev tsim hluav taws xob thiab kev sib koom ua ke.