1、石(shi)英(ying)(ying)(ying)鐘(zhong)走時(shi)(shi)(shi)準、耗電(dian)(dian)省、經(jing)久耐(nai)用為其大優點。不論是(shi)(shi)老(lao)式(shi)石(shi)英(ying)(ying)(ying)鐘(zhong)或是(shi)(shi)新式(shi)多功能石(shi)英(ying)(ying)(ying)鐘(zhong)都是(shi)(shi)以石(shi)英(ying)(ying)(ying)晶(jing)(jing)體(ti)(ti)振(zhen)(zhen)蕩(dang)(dang)(dang)器(qi)為核(he)心電(dian)(dian)路(lu),其頻率精度(du)決(jue)定了電(dian)(dian)子(zi)鐘(zhong)表(biao)的(de)(de)走時(shi)(shi)(shi)精度(du)。從石(shi)英(ying)(ying)(ying)晶(jing)(jing)體(ti)(ti)振(zhen)(zhen)蕩(dang)(dang)(dang)器(qi)原理的(de)(de)示(shi)意圖(tu)中,其中V1和V2構成CMOS反(fan)(fan)相器(qi)石(shi)英(ying)(ying)(ying)晶(jing)(jing)體(ti)(ti)Q與振(zhen)(zhen)蕩(dang)(dang)(dang)電(dian)(dian)容(rong)C1及微調(diao)(diao)電(dian)(dian)容(rong)C2構成振(zhen)(zhen)蕩(dang)(dang)(dang)系(xi)統,這(zhe)里石(shi)英(ying)(ying)(ying)晶(jing)(jing)體(ti)(ti)相當于(yu)電(dian)(dian)感。振(zhen)(zhen)蕩(dang)(dang)(dang)系(xi)統的(de)(de)元件參數(shu)確定了振(zhen)(zhen)頻率。一般Q、C1及C2均為外(wai)接(jie)元件。另外(wai)R1為反(fan)(fan)饋電(dian)(dian)阻,R2為振(zhen)(zhen)蕩(dang)(dang)(dang)的(de)(de)穩定電(dian)(dian)阻,它們都集成在(zai)電(dian)(dian)路(lu)內部。故無(wu)法(fa)通(tong)過改(gai)變(bian)(bian)C1或C2的(de)(de)數(shu)值來調(diao)(diao)整(zheng)走時(shi)(shi)(shi)精度(du)。但此時(shi)(shi)(shi)我們仍(reng)可用加接(jie)一只(zhi)(zhi)電(dian)(dian)容(rong)C有方(fang)法(fa),來改(gai)變(bian)(bian)振(zhen)(zhen)蕩(dang)(dang)(dang)系(xi)統參數(shu),以調(diao)(diao)整(zheng)走時(shi)(shi)(shi)精度(du)。根(gen)據電(dian)(dian)子(zi)鐘(zhong)表(biao)走時(shi)(shi)(shi)的(de)(de)快(kuai)(kuai)慢(man),調(diao)(diao)整(zheng)電(dian)(dian)容(rong)有兩種接(jie)法(fa):若(ruo)走時(shi)(shi)(shi)偏快(kuai)(kuai),則(ze)可在(zai)石(shi)英(ying)(ying)(ying)晶(jing)(jing)體(ti)(ti)兩端(duan)并接(jie)電(dian)(dian)容(rong)C,如(ru)圖(tu)4所(suo)(suo)示(shi)。此時(shi)(shi)(shi)系(xi)統總電(dian)(dian)容(rong)加大,振(zhen)(zhen)蕩(dang)(dang)(dang)頻率變(bian)(bian)低,走時(shi)(shi)(shi)減(jian)慢(man)。若(ruo)走時(shi)(shi)(shi)偏慢(man),則(ze)可在(zai)晶(jing)(jing)體(ti)(ti)支路(lu)中串接(jie)電(dian)(dian)容(rong)C。如(ru)圖(tu)5所(suo)(suo)示(shi)。此時(shi)(shi)(shi)系(xi)統的(de)(de)總電(dian)(dian)容(rong)減(jian)小,振(zhen)(zhen)蕩(dang)(dang)(dang)頻率變(bian)(bian)高,走時(shi)(shi)(shi)增快(kuai)(kuai)。只(zhi)(zhi)要經(jing)過耐(nai)心的(de)(de)反(fan)(fan)復試驗,就可以調(diao)(diao)整(zheng)走時(shi)(shi)(shi)精度(du)。因此,晶(jing)(jing)振(zhen)(zhen)可用于(yu)時(shi)(shi)(shi)鐘(zhong)信號發生器(qi)。
2、隨著電視(shi)技術(shu)的發展,近(jin)來彩電多采用500kHz或503 kHz的晶(jing)(jing)體振(zhen)蕩(dang)器(qi)作為(wei)行、場(chang)電路(lu)的振(zhen)蕩(dang)源,經1/3的分頻(pin)得到 15625Hz的行頻(pin),其穩定性(xing)和可靠(kao)性(xing)大為(wei)提高。面且晶(jing)(jing)振(zhen)價格便宜,更(geng)換容易。
3、在通(tong)信(xin)系統產品中,石英晶體(ti)振(zhen)蕩器的(de)價值得到(dao)了更廣泛的(de)體(ti)現,同時也(ye)得到(dao)了更快的(de)發展。許(xu)多高(gao)性能(neng)的(de)石英晶振(zhen)主要應用于(yu)通(tong)信(xin)網絡、無線數(shu)(shu)據傳(chuan)輸、高(gao)速數(shu)(shu)字(zi)數(shu)(shu)據傳(chuan)輸等。