PROM vs EPROM
Hauv cov khoom siv hluav taws xob thiab kev suav, cov ntsiab lus nco yog qhov tseem ceeb los khaws cov ntaub ntawv thiab khaws lawv tom qab. Nyob rau hauv cov theem ntxov tshaj plaws, cov ntaub nplaum nplaum tau siv los ua lub cim xeeb thiab nrog cov khoom siv hluav taws xob hloov pauv lub cim xeeb kuj tau tsim los ntawm semiconductors. EPROM thiab EEPROM yog hom tsis-volatile semiconductor nco.
Yog tias lub cim xeeb tsis tuaj yeem khaws cov ntaub ntawv tom qab txiav tawm ntawm lub zog, nws yog lub npe hu ua lub cim xeeb tsis muaj zog. PROMs thiab EPROMs tau pioneering technologies nyob rau hauv nonvolatile nco hlwb (piv txwv li lawv muaj peev xwm khaws cov ntaub ntawv tom qab disconnecting ntawm lub hwj chim) uas coj mus rau txoj kev loj hlob ntawm niaj hnub khoom lub xeev nco pab kiag li lawm.
PROM yog dab tsi?
PROM stands rau Programmable Read Only Memory, ib hom kev nco tsis hloov pauv uas tsim los ntawm Weng Tsing Chow hauv xyoo 1959 raws li kev thov los ntawm US Air Force ua lwm txoj hauv kev nco txog Atlas E thiab F ICBM qauv onboard (airborne) digital computer. Lawv tseem hu ua One-Time Programmable Non-Volatile Memory (OTP NVM) thiab Field Programmable Read Only Memory (FPROM). Tam sim no cov no tau siv dav hauv microcontrollers, xov tooj ntawm tes, Xov tooj cua Zaus ID phaib (RFIDs), High Definition Media Interfaces (HDMI), thiab video game controllers.
Cov ntaub ntawv sau rau ntawm PROM yog qhov ruaj khov thiab hloov tsis tau; yog li ntawd, lawv feem ntau siv los ua lub cim xeeb zoo li qub xws li firmware ntawm cov khoom siv. Thaum ntxov BIOS chips kuj yog PROM chips. Ua ntej programming, lub nti tsuas muaj cov khoom nrog tus nqi "1". Hauv cov txheej txheem programming, tsuas yog cov khoom yuav tsum tau hloov mus rau xoom "0" los ntawm tshuab txhua lub fuse khoom. Thaum lub nti yog programmed cov txheej txheem yog irreversible; yog li ntawd, cov nqi no yog hloov tsis tau thiab mus tas li.
Raws li cov cuab yeej tsim khoom, cov ntaub ntawv tuaj yeem ua haujlwm ntawm wafer, kev sim zaum kawg, lossis qib kev sib koom ua ke. Cov no yog programmed siv PROM programmer uas tshuab lub fuses ntawm txhua qhov me me los ntawm kev siv qhov hluav taws xob loj heev rau kev pab cuam lub nti (feem ntau 6V rau 2nm tuab txheej). PROM hlwb txawv ntawm ROMs; Lawv tuaj yeem raug programmed txawm tias tom qab tsim khoom, qhov ROMs tsuas yog tuaj yeem ua haujlwm ntawm kev tsim khoom.
EPROM yog dab tsi?
EPROM sawv cev rau Erasable Programmable Read Only Memory, kuj yog ib pawg ntawm cov khoom siv nco tsis hloov pauv uas tuaj yeem raug programmed thiab tshem tawm. EPROM tau tsim los ntawm Dov Frohman ntawm Intel hauv 1971 raws li kev tshawb nrhiav rau hauv kev sib txuas ua ke tsis raug qhov twg qhov rooj sib txuas ntawm cov transistors tau tawg.
Ib qho EPROM nco cell yog cov khoom loj ntawm cov rooj vag ntab Field Effect Transistors. Cov ntaub ntawv (txhua me ntsis) yog sau rau ntawm tus kheej Field Effect Transistors hauv lub nti siv tus programmer uas tsim cov dej ntws tawm sab hauv. Raws li qhov chaw nyob ntawm tes ib qho FET khaws cov ntaub ntawv thiab qhov hluav taws xob ntau dua li qhov qub digital circuit khiav hauj lwm voltages yog siv rau hauv kev ua haujlwm no. Thaum qhov hluav taws xob raug tshem tawm, cov hluav taws xob tau daig hauv cov electrodes. Vim nws cov conductivity tsawg heev silicon dioxide (SiO2) rwb thaiv tsev txheej ntawm lub rooj vag khaws cia tus nqi rau lub sij hawm ntev, li no khaws lub cim xeeb rau kaum mus rau nees nkaum xyoo.
Ib EPROM nti yog tshem tawm los ntawm kev raug UV muaj zog xws li Mercury vapor teeb. Erasure tuaj yeem ua tiav siv lub teeb UV nrog lub wavelength luv dua 300nm thiab nthuav tawm rau 20 -30 feeb ntawm qhov ze (<3cm). Rau qhov no, EPROM pob yog tsim nrog lub qhov rais fused quartz uas nthuav tawm cov silicon nti rau lub teeb. Yog li ntawd, ib qho EPROM tau yooj yim txheeb xyuas los ntawm cov yam ntxwv fused quartz qhov rais. Erasure tuaj yeem ua tiav siv X-rays ib yam nkaus.
EPROMs yog siv los ua cov khw muag khoom nco zoo li qub hauv cov voj voog loj. Lawv tau dav siv los ua BIOS chips hauv computer motherboards, tab sis lawv tau hloov pauv los ntawm cov thev naus laus zis tshiab xws li EEPROM, uas pheej yig dua, me dua thiab sai dua.
Qhov txawv ntawm PROM thiab EPROM yog dab tsi?
• PROM yog cov thev naus laus zis qub thaum PROM thiab EPROM yog cov khoom siv nco tsis muaj zog.
• PROMs tuaj yeem tsim tau ib zaug xwb thaum EPROMs rov siv tau thiab tuaj yeem ua haujlwm tau ntau zaus.
• Cov txheej txheem hauv kev ua haujlwm ntawm PROMS yog qhov hloov tsis tau; li no lub cim xeeb mus tas li. Hauv EPROMs nco tuaj yeem tshem tawm los ntawm kev raug UV teeb.
• EPROMs muaj fused quartz qhov rais hauv ntim kom tso cai rau qhov no. PROMs tau muab ntim rau hauv cov ntim yas tiav; Yog li UV tsis cuam tshuam rau PROMs
• Hauv PROMs cov ntaub ntawv yog sau / programmed rau hauv nti los ntawm tshuab lub fuses ntawm txhua qhov me me uas siv ntau qhov hluav taws xob ntau dua li qhov nruab nrab voltages siv hauv digital circuits. EPROMS kuj siv high voltage, tab sis tsis txaus los hloov cov semiconductor txheej mus tas li.
