Txoj Cai Ua Haujlwm ntawm PTC Thermistor
Feem ntau PTC thermistor yog tsim los nrog doped polycrystalline ceramics, uas suav nrog BaTiO3 (barium titanate) thiab lwm yam sib xyaw. Cov ntaub ntawv no muaj cov cuab yeej ntawm kev nce hluav taws xob tam sim ntawd ntawm qhov ntsuas kub tseem ceeb. Barium titanate (BTO) cov khoom siv yog cov khoom siv ferroelectric uas nws qhov dielectric qhov sib txawv ntawm qhov kub thiab txias.
Lub hauv paus ntsiab lus ntawm kev ua haujlwm ntawm PTC thermistor feem ntau yog nyob ntawm qhov kev hloov ntawm kev ua haujlwm los ntawm kev hloov pauv ntawm qhov kub thiab txias. Thaum qhov kub nce, qhov kev tiv thaiv nce. Raws li qhov kub thiab txias, qhov tsis kam txo. Yog li nyob rau hauv hom thermistor, ob qho tib si kuj thiab kub yog ncaj qha proportional.
Hom PTC Thermistor
Thermistors tau muab faib ua peb hom raws li cov qauv, cov khoom siv thiab cov txheej txheem tsim khoom, xws li hloov cov ceramic, silicon resistor thiab polymer PPTC.
1. Silicon PTC thermistor
Pawg no ntawm cov thermistor feem ntau yog siv cov khoom siv silicon semiconductor, cov no yog cov khoom siv linear nrog PTC (Positive Temperature Coefficient) tsis kam. Lawv qhia NTC (Tsis Zoo Kub Coefficient) thaum kub siab tshaj 150 degree. Cov thermistors no yog siv los ua PTC kub sensors vim lawv cov yam ntxwv linear thiab tuaj yeem siv rau kev them nyiaj kub.
2. Ceramic hloov PTC thermistor
Hom thib ob yog ceramic hloov PTC thermistor, uas muaj qhov tsis tshua muaj kev tiv thaiv-kub nkhaus. Thaum lub thermistor yog energized, qhov kev tiv thaiv pib txo kom txog thaum lub ntsuas kub ruaj khov. Thaum qhov kub nce siab tshaj ib theem, qhov kev tiv thaiv nce ntau heev. Qhov no thermistor yog dav siv nyob rau hauv sensors, PTC heaters, thiab kuj yuav siv tau rau over-temperature tiv thaiv, tiv thaiv tam sim no, lub sij hawm ncua kev tiv thaiv thiab kub them nyiaj.
3. Polymer PPTC thermistor
Polymer zoo kub coefficient thermistors, los yog PPTC thermistor, kuj hu ua resettable fuses vim hais tias lawv muaj ib tug tsis-linear PTC nyhuv. Hom thermistor no yog lub tshuab ua kom muaj cua sov, yog li txhua qhov kev hloov pauv hauv qhov ntsuas kub yuav cuam tshuam rau lub thermistor kev ua haujlwm. Lub thermistor no muaj qhov tsis kam tsawg tsawg nyob rau hauv kev ua haujlwm ib txwm muaj thiab muaj kev tswj xyuas tsawg dua ntawm kev ua haujlwm ntawm lub voj voog ntau dua li qhov seem ntawm lub voj voog.
Txawm li cas los xij, yog tias lub tshuab hluav taws xob nkag mus rau qhov teeb meem txhaum cai, PPTC teb tam sim ntawd los ntawm kev nkag mus rau qhov xwm txheej. Thaum qhov teeb meem raug tshem tawm, lub thermistor yuav rov pib dua nws tus kheej thiab lub circuitry yuav rov qab mus rau nws qhov kev ua haujlwm zoo.
Cov thermistor no yog siv rau hauv cov txheej txheem tswj thiab kev tiv thaiv tsheb, kev sib txuas lus, khoom siv hluav taws xob, khoom siv kho mob.
