Isano Hagati yumutwaro wo hanze nubushobozi bwa Crystal Oscillator

Mumuzunguruko wa elegitoronike, oscillator ya kristu nimwe mumasoko asanzwe. Kugirango umenye neza ko oscillator itangira kunyeganyega bisanzwe kandi ikora neza, ubushobozi bwimitwaro yo hanze mumuzunguruko igomba kuba yarateguwe muburyo bushingiye kubushobozi bwa Load Capacitance (yitwa CL). Guhuza ubushobozi bwa capacitor ntibishobora gutera ingorane mugutangira kunyeganyega, kwiyongera kwinshyi, cyangwa sisitemu idahungabana.

Iyi ngingo izasobanura mu buryo burambuye ibisobanuro bya kristal oscillator yumutwaro, uburyo bwo kubara bwa capacitori zo hanze, hamwe nibitekerezo bifatika mugushushanya.

1. Ubushobozi bwo Gutwara (CL) bwa Oscillator ya Crystal ni ubuhe?

Abakora inganda za Crystal oscillator mubisanzwe bagaragaza ubushobozi bwumutwaro nominal CL muri datasheet, nka 18pF, 20pF, 12pF, nibindi.

Muyandi magambo, oscillator ya kristu irashobora gusohora inshuro nyayo mugihe ubushobozi bwumutwaro uhwanye na CL.

2. Ni gute ubushobozi bwo hanze bugira ingaruka ku bushobozi bwo gutwara imizigo?

Inzira isanzwe ya kristu oscillator niyi ikurikira:

C1 na C2 nubushobozi bubiri buhujwe hanze na GND (mubisanzwe chip capacator);

Impera zombi za XTAL zahujwe na pin ebyiri za kristu oscillator;

Mubyukuri, ubushobozi buringaniye bwa capacitance CL ya kristal oscillator iboneka hamwe nurukurikirane rwihuza rwa C1 na C2, hiyongereyeho ubushobozi bwa parasitike Cp yatangijwe nubuyobozi bwa PCB hamwe nububiko.

3. Imibare yo kubara: Nigute dushobora kuvana indangagaciro zubushobozi bwo hanze bushingiye kuri CL?

Inzira yubushobozi bungana (CL) nuburyo bukurikira:

AMASOKO:

C1, C2: Ubushobozi bwahujwe hanze na GND;

Cp: ​​Ubushobozi bwa parasitike bwatangijwe na PCB, gupakira, nibindi (mubisanzwe 2pF ~ 5pF, bishobora kugereranywa hakoreshejwe kwigana cyangwa uburambe);

CL: Nominal load capacitance yatanzwe muri kristu oscillator datasheet.

[Urugero]

Dufate ko ibisobanuro bya kristu oscillator ari CL=18 pF, na capacitance ya PCB parasitike Cp ≈ 5pF. Kubona C1 na C2 bikwiye:

Banza usimbuze muri formula:

Dufate C 1=C 2=C, formula yoroshye kuri:

Gukemura kuri C:

Kubwibyo, birasabwa gukoresha ubushobozi bwo hanze C 1=C 2=27 pF (agaciro gasanzwe).

4. Kuki Ubushobozi bwo hanze budahuye butera ibibazo?

Gutandukana kwinshuro: Niba ubushobozi bwo hanze ari buto cyane cyangwa bunini cyane, oscillator ya kristu izatandukana numurongo wacyo wizina, bigatuma sisitemu itandukana;

Kunyeganyega bigoye cyangwa bidahindagurika: Umutwaro urenze urugero uzagabanya inyungu, zishobora gutuma oscillator ya kristu idashobora gutangira kunyeganyega cyangwa kugira amajwi ya jitter;

Kongera ingufu z'amashanyarazi: Umutwaro udakwiye bizatuma kongera ingufu z'umuzunguruko wa kristu oscillator;

Kwiyongera kwa EMI: Ihungabana ridahindagurika rishobora kubyara inshuro zidasanzwe, bigira ingaruka kuri electromagnetic ihuza sisitemu.

5. Gushushanya Ibyifuzo hamwe nubwubatsi

Witondere witonze kristu oscillator datasheet

Sobanura agaciro ka CL;

Sobanura neza topologiya isabwa;

Reba niba urwego rusabwa rwubushobozi bwo hanze bwatanzwe.

Reba ibidukikije byukuri

Gereranya Cp ukoresheje kwigana PCB cyangwa uburambe;

Kumurongo muremure - umuvuduko cyangwa amasaha asobanutse (urugero, sisitemu yitumanaho, inshuro nkuru ya MCU> 100MHz), birasabwa kubara neza cyangwa kugerageza.

Koresha ubushobozi bwa simmetrike

Mubisanzwe, birasabwa ko C 1=C2 gushyira hagati yumurongo no kuringaniza urusaku;

Igishushanyo mbonera gishobora no gukoreshwa niba hari ibisabwa byihariye bihuye.

Koresha chip capacitor array mugihe cyo gukemura

Guhuza ibigeragezo birashobora gukorwa hamwe na chip capacitor (urugero, 10pF, 15pF, 22pF, 27pF, nibindi);

Koresha isesengura ryisesengura cyangwa oscilloscope kugirango ugenzure ibisohoka bihamye hamwe nukuri.

6. Ibibazo bisanzwe (FAQ)

Igisubizo cyibibazo

Umwanzuro

Igishushanyo mbonera cyumutwaro wo hanze kuri kristu oscillator ni ntoya ariko irambuye igira ingaruka itaziguye kandi ihamye ya sisitemu yisaha. Gusobanukirwa isano iri hagati ya CL na C1 / C2, no guhindura ibipimo ukurikije ubushobozi bwa parasitike ya PCB, nurufunguzo rwo kugera ku ihindagurika rihamye hamwe ninshuro zuzuye.

Muri - yihuta sisitemu yububiko, ibikoresho byitumanaho, cyangwa sisitemu ifite amasaha menshi cyane asabwa, guhitamo neza no guhuza kristal oscillator yimitwaro ni umurimo wubwubatsi ugomba gufatanwa uburemere.

HANGJING ifite laboratoire yabigize umwuga hamwe naba injeniyeri benshi basaba bafite uburambe bwimyaka irenga 20, ishobora guha abakiriya serivisi zipima umwuga kubuntu. Niba ufite ibyo ukeneye, nyamuneka hamagara kugurisha cyangwa abakozi bacu tekinike.