Crystal oscillator ndiye chinsinsi mu kapangidwe ka digito, nthawi zambiri pamapangidwe ozungulira, oscillator wa kristalo amagwiritsidwa ntchito ngati mtima wa digito, ntchito zonse zamagawo a digito ndizosalekanitsidwa ndi chizindikiro cha wotchi, ndipo crystal oscillator ndiye batani lofunikira. zomwe zimayendetsa mwachindunji chiyambi cha dongosolo lonse, zikhoza kunenedwa kuti ngati pali mapangidwe ozungulira digito akhoza kuona crystal oscillator.

I. Kodi kristalo oscillator ndi chiyani?

Crystal oscillator nthawi zambiri amatanthauza mitundu iwiri ya quartz crystal oscillator ndi quartz crystal resonator, ndipo imathanso kutchedwa crystal oscillator. Onsewa amapangidwa pogwiritsa ntchito piezoelectric zotsatira za makhiristo a quartz.

Crystal oscillator imagwira ntchito motere: pamene magetsi akugwiritsidwa ntchito pamagetsi awiri a kristalo, kristaloyo idzawonongeka ndi makina, ndipo m'malo mwake, ngati mphamvu yamagetsi ikugwiritsidwa ntchito kumapeto kwa kristalo, kristaloyo idzatulutsa. malo amagetsi. Chodabwitsa ichi ndi chosinthika, chifukwa chake kugwiritsa ntchito mawonekedwe a kristalo, ndikuwonjezera kusinthasintha kwa malekezero onse a kristalo, chip chimatulutsa kugwedezeka kwamakina, ndipo nthawi yomweyo kutulutsa minda yamagetsi yosinthira. Komabe, kugwedezeka uku ndi magetsi opangidwa ndi kristalo nthawi zambiri amakhala ochepa, koma malinga ngati ali pafupipafupi, matalikidwewo adzawonjezeka kwambiri, mofanana ndi LC loop resonance yomwe ife okonza madera timawona nthawi zambiri.

II. Gulu la ma crystal oscillations (ogwira ntchito komanso osasamala)

① Passive crystal oscillator

Passive crystal ndi kristalo, nthawi zambiri chipangizo cha 2-pin non-polar (kristalo wina wosakhazikika amakhala ndi pini yokhazikika yopanda polarity).

Passive crystal oscillator nthawi zambiri amafunikira kudalira wotchi yomwe imapangidwa ndi capacitor yonyamula katundu kuti ipangitse chizindikiro cha oscillating (sine wave sign).

② Oscillator yogwira ntchito

An yogwira kristalo oscillator ndi oscillator, kawirikawiri ndi 4 mapini. Active crystal oscillator safuna oscillator wamkati wa CPU kuti apange chizindikiro cha square wave. Mphamvu ya kristalo yogwira imapanga chizindikiro cha wotchi.

Chizindikiro cha oscillator yogwira kristalo ndi chokhazikika, khalidwe ndilabwino, ndipo njira yolumikizira ndiyosavuta, cholakwika cholondola ndi chocheperako kuposa cha oscillator wa crystal oscillator, ndipo mtengo wake ndi wokwera mtengo kuposa oscillator wa kristalo.

III. Magawo oyambira a crystal oscillator

Magawo oyambira a crystal oscillator ndi awa: kutentha kwa ntchito, mtengo wolondola, kuthekera kofananira, mawonekedwe a phukusi, pafupipafupi pakatikati ndi zina zotero.

Mafupipafupi amtundu wa crystal oscillator: Kusankhidwa kwa ma frequency a crystal wamba kumatengera zomwe zimafunikira pafupipafupi, monga MCU nthawi zambiri imakhala yosiyana, ambiri mwa iwo amachokera ku 4M mpaka makumi angapo a M.

Kulondola kwa Crystal vibration: kulondola kwa kugwedezeka kwa kristalo nthawi zambiri kumakhala ± 5PPM, ± 10PPM, ± 20PPM, ± 50PPM, etc., tchipisi ta wotchi yolondola kwambiri nthawi zambiri zimakhala mkati mwa ± 5PPM, ndipo kugwiritsa ntchito nthawi zambiri kumasankha ± 20PPM.

Mphamvu yofananira ya kristalo oscillator: kawirikawiri posintha mtengo wa mphamvu yofananira, mafupipafupi apakati a crystal oscillator akhoza kusinthidwa, ndipo pakalipano, njirayi imagwiritsidwa ntchito pokonza oscillator wapamwamba kwambiri.

M'magawo ozungulira, mzere wa mawotchi othamanga kwambiri umakhala wofunika kwambiri. Mzere wa wotchi ndi chizindikiro chodziwika bwino, ndipo kuwonjezereka kwafupipafupi, kufupikitsa mzerewu kumafunika kuonetsetsa kuti kusokonezeka kwa chizindikirocho ndi kochepa.

Tsopano m'madera ambiri, kristalo wotchi pafupipafupi dongosolo ndi mkulu kwambiri, kotero mphamvu kusokoneza harmonics ndi amphamvu, harmonics adzakhala anachokera ku athandizira ndi linanena bungwe mizere iwiri, komanso cheza danga, amenenso kumabweretsa ngati PCB masanjidwe a kristalo oscillator si wololera, izo mosavuta kuchititsa amphamvu osokera cheza vuto, ndipo kamodzi atapangidwa, n'zovuta kuthetsa ndi njira zina. Choncho, ndikofunika kwambiri kuti kristalo oscillator ndi CLK chizindikiro mzere masanjidwe pamene bolodi PCB waikidwa.