Cov kua siv lead ua kua yog tsim los ntawm ntau cov ntsiab lus pixel. Xws li pixels yog illuminated los ntawm ib tug tas li lub teeb-emitting backlight. Lub teeb nraub qaum tas li tshem tawm qhov tshwm sim ntawm qhov tshwm sim ntawm lub ntsej muag zoo ib yam li CRT zaub (uas yog, lub pulsation ntawm fluorescence hauv txhua lub voj voog tshiab). Daim duab 1 yog daim duab schematic ntawm cov qauv ntawm ib lub LCD pixel. Lub pixel muaj ob sab saum toj thiab qis hlau clamping daim hlau, uas peb hu ua polarizing daim hlau. Muaj qhov sib koom ua ke ntawm cov phaj polarizing clamps, raws li pom nyob rau hauv daim duab 1. Cov slots no yog parallel mus rau lub dav hlau siv lead ua ntawm cov kua siv lead ua kua molecules thiab tso cai rau lub backlight qhov chaw dhau los ntawm qis polarizing phaj upwards, thiab tib lub sij hawm, cov kua siv lead ua kua molecules yog siv los xa lub teeb mus rau sab sauv polarizing phaj. Yog li ntawd, qhov luminous siv ntawm cov kua siv lead ua kua yog nyob ntawm qhov kev taw qhia ntawm cov kua siv lead ua kua molecules thiab yog proportional rau cov khoom voltage.
Daim duab 1. Daim duab schematic ntawm ib lub LCD pixel nrog rau sab sauv thiab qis polarizing daim hlau thiab cov kua siv lead ua kua molecules.
Daim duab 2 yog daim duab schematic ntawm lub voj voog tsav tsheb rau ib qho LCD pixel. Lub rooj vag (GATE) voltage yog siv los ua lub teeb liab hloov thiab yog amplified los ntawm -5V rau 20V. Tus nqi raug ntawm cov teeb liab video feem ntau yog nyob rau hauv thaj tsam ntawm 0V txog 10V, uas yog siv los tswj cov luminous siv ntawm txhua cov kua siv lead ua pixel. Cov txheej hauv qab ntawm lub pixel feem ntau txuas nrog rau hauv qab rov qab substrate ntawm lub vaj huam sib luag, thiab cov node voltage ntawm lub substrate hauv qab no hu ua Vcom voltage.
Daim duab 2. Schematic daim duab ntawm ib qho LCD pixel tsav Circuit Court.
Txawm hais tias cov qauv hauv Circuit Court tau qhia hauv daim duab 2 tuaj yeem ua haujlwm ib txwm, txoj kev no yuav ua rau lub neej luv ntawm LCD npo. Peb xav tias qhov voltage ntawm Vcom yog grounded. Thaum qhov voltage ntau ntawm cov teeb liab video thov ntawm pixels yog los ntawm 0V txog 10V, nws tuaj yeem xav tias qhov nruab nrab tus nqi ntawm qhov voltage yog 5V. Ces muaj xws li ib tug ruaj khov DC voltage uas yuav siv tau rau cov kua siv lead ua saum toj no ob tug ncej ntawm lub pixel, nws ncaj qha mus rau lub tsub zuj zuj ntawm nqi thiab cov duab tuav ntawm qhov sib npaug capacitance Cs ntawm lub pixel. Nyob rau hauv lub sij hawm ntev, qhov saum npoo ntawm ion plating txheej ntawm cov kua siv lead ua pixel yuav tau ntim nrog impurities thiab plua plav vim qhov kev txiav txim ntawm lub tshuab hluav taws xob, uas yuav ua rau cov kua siv lead ua kua plating txheej rau hnub nyoog, degrade, thiab txawm tias ua rau mob hnyav. duab tuav, uas yog qhov peb feem ntau hu ua duab smearing thiab teb qeeb.
Los ntawm daim duab schematic 1, peb nkag siab tias LCD vaj huam sib luag muaj cov qauv sib luag, uas txhais tau hais tias ob qho tib si zoo thiab tsis zoo voltages tuaj yeem siv los tswj kev teeb tsa thiab faib cov kua siv lead ua kua molecules. Peb tuaj yeem siv qhov tshwj xeeb no txav Vcom voltage mus rau qhov nruab nrab 5V ntawm lub teeb liab video los ntawm OV mus rau 10V, kom lub amplitude ntawm lub teeb liab video nyob rau sab sauv thiab sab qis ntawm Vcom voltage, thiab tsim ib tug xoom voltage rau lub pixel. Qhov zero point no tuaj yeem tshem tawm cov laus thiab cov duab khaws cia tsis xws luag ntawm cov kua siv lead ua kua. Txawm li cas los xij, txij li qhov ci ntsa iab tshaj plaws ntawm cov teeb liab video hloov pauv los ntawm thawj 10V mus rau 5V tam sim no, thawj qhov kev daws teeb meem yuav raug txi rau hauv txoj kev no.
Peb yuav tsum tau kho qhov Vcom voltage kom raug raws li qhov nruab nrab ntawm lub teeb liab video los daws qhov teeb meem flicker ntawm LCD npo. Muab piv txwv vim li cas lub vijtsam LCD yuav flicker. Peb xav tias lub Hoobkas Vcom voltage ntawm LCD npo yog 5.5V, thiab lub amplitude ntawm lub teeb liab video yog nyob nruab nrab ntawm OV thiab 10V. Nyob rau hauv txoj kev no, nyob rau hauv tag nrho cov voltage ntau, txhua cheeb tsam yuav muaj ib tug sib txawv segment voltage nqi, ib cheeb tsam yog 4.5V, thiab lwm qhov chaw yog 5.5V. Raws li tag nrho cov kev ntsuas hluav taws xob muaj kev txhawj xeeb, qhov sib txawv ntawm cov hluav taws xob sib txawv yuav ua rau lub teeb ci sib txawv, uas yog cov kua siv lead ua kua flicker tshwm sim peb tau hais los saum toj no.
Vim qhov sib txawv ntawm cov txheej txheem tsim khoom ntawm txhua lub vaj huam sib luag LCD, lub pixel Vcom voltage siv taw tes yuav txawv ntawm vaj huam sib luag rau vaj huam sib luag lossis ntawm ib tus neeg vaj huam sib luag. Thawj lub Hoobkas LCD vaj huam sib luag yuav tsum nruj me ntsis kho qhov ntsuas no kom tsis txhob muaj lub teeb tsis sib xws ntawm pixels. Lub hauv paus substrate ntawm lub vijtsam me tuaj yeem lees paub tias tsis tshua muaj kev tiv thaiv hauv av, peb tsuas yog yuav tsum tau ntxiv ib qho tib-channel mechanical potentiometer los kho tus nqi Vcom voltage rau kev kho phau ntawv. Txoj kev no yog tsim rau me me los yog me ntsis loj dua panels, tab sis qhov tseeb tsis yog siab, thiab kev hloov kho tus nqi ntawm cov cuab yeej siv no yog qhov yooj yim heev los hloov thaum lub tshuab tag nrho yog sib sau ua ke thiab muab tso rau hauv module. Rau cov lus qhia loj dua 19", cov phaj hauv qab tsis sib npaug rau ib qho kev tiv thaiv qis dua, yog li peb yuav tsum tau ua ntau yam kev kho ntawm ntau qhov sib txawv ntawm qhov loj-qhov screen. Feem ntau 5 ntsiab lus nrog 4 fab thiab 1 nruab nrab taw tes yog siv txoj kev them nyiaj. Lub sijhawm no, cov chaw tsim khoom tuaj yeem siv ntau lub tshuab hluav taws xob digital (DCP) los hloov kho kom ua tiav cov haujlwm uas phau ntawv hloov kho ntawm cov tshuab potentiometers tsis tuaj yeem ua.
Daim duab 3, daim duab kos duab ntawm lub digital potentiometer DCP thiab Vcom circuit nrog kev ua haujlwm.
Nws yog qhov yooj yim heev los hloov lub tshuab potentiometer rau hauv digital potentiometer hauv lub cuab yeej. Daim duab 3 qhia txog kev siv lub buffered digital potentiometer raws li Vcom tsav daim ntawv thov daim duab kos. ISL45042 yog cov zis tam sim no, tsis yog-volatile digital potentiometer (DCP), nws cov analog AVDD ua haujlwm voltage yog txog 20V. Nws txais ob-xaim uplink thiab downlink interfaces, tus naj npawb ntawm cov khoom yog mus txog 7 cov khoom, thiab qhov siab tshaj plaws ntawm 128-ntu hloov. Tus nqi Vcom hloov kho tuaj yeem khaws cia hauv EEPROM ntawm lub rooj tsav xwm Circuit Court. Tus nqi hluav taws xob ntawm cov hluav taws xob digital yog 2.25V txog 3.6V, thiab nws tuaj yeem sib txuas lus nrog ntau tus tswj ntawm lub khw. Cov analog voltage muab rau tus ntaiv kuj tuaj yeem nyob ntawm 4.5V txog 20V. Qhov no yog qhov taw qhia tseem ceeb heev rau cov ntxaij vab tshaus LCD me me. Yog vim li cas yog tias tus nqi ntawm analog voltage rau cov ntxaij vab tshaus me me yog tsawg dua 10V, thiab tib lub sijhawm, nws loj dua me ntsis. Lub vijtsam yuav tsum siv qhov hluav taws xob ntau tshaj 15V. Cov zis hluav taws xob ntawm digital potentiometer yog buffered rau Vcom tsheb npav tso tawm los ntawm EL5111 (cov zis tam sim no yog 180mA).
