Ib, Tsav lub hauv paus ntsiab lus ntawm segmented LCD: hluav taws xob teb teb thiab dynamic scanning
Lub hauv paus ntawm segmented LCD yog lub teb hluav taws xob teb cov yam ntxwv ntawm cov kua siv lead ua kua molecules. Thaum ib qho kev hloov hluav taws xob raug siv thoob plaws cov electrodes, cov kev taw qhia ntawm cov kua siv lead ua kua molecules twists, hloov cov pob tshab thiab yog li tswj qhov ci ntawm tus cwj mem. Nws tsav tsheb yuav tsum ua kom tau raws li ob lub ntsiab lus tseem ceeb:
AC tsav: Cov kua siv lead ua kua molecules rhiab heev rau DC voltage, thiab ntev - daim ntawv thov tuaj yeem ua rau cov tshuaj degradation. Yog li, AC tsav yuav tsum tau siv los xyuas kom meej tias qhov nruab nrab qhov hluav taws xob siv rau ob qhov kawg ntawm LCD yog 0.
Dynamic scanning: Los ntawm kev siv segmented scanning txoj kev, tsuas yog ib qho COM (common electrode) scan siv tau txhua lub sijhawm, thiab COM seem nyob rau hauv lub xeev tsis raug cai kom tsis txhob cuam tshuam kev cuam tshuam. Piv txwv li, 1/4 Lub Luag Haujlwm (4 COM) LCD xav tau kom ua tiav ntau ntu los ntawm kev hloov pauv COM sai sai.
Ua ib ntu code LCD nrog lub zog ua haujlwm ntawm 3.3V, 1/4 Lub Luag Haujlwm, thiab 1/3 Bias ua piv txwv, nws qhov kev tsav tsheb voltage yog txog 1.1V (3.3V / 3). Thaum qhov hluav taws xob hla ib ntu LCD siab dua 1.1V, nws yuav tso tawm, thiab thaum nws qis dua 1.1V, nws yuav tua. Txhawm rau kom tsis txhob muaj dab tsi tshwm sim (cov zaub tsis muaj zog), nws yog ib qho tsim nyog los xyuas kom meej tias qhov sib txawv ntawm qhov hluav taws xob thaum lub sij hawm tso saib yog ntau dua lossis sib npaug rau 3.0V thiab Tsawg dua lossis sib npaug rau 1.0V thaum muab tua.
2, Kho vajtse tsim: MCU tus pin ncaj qha tsav thiab kev xaiv tus tswj hwm tshwj xeeb
1. MCU tus pin direct tsav tswvyim
Haum rau kev lag luam twj paj nruag nrog tsawg ntu (xws li 4 cov khoom thiab 8 ntu), nws tuaj yeem txo cov nqi thiab thaj chaw PCB. Siv MM32F031C6T6 ua piv txwv:
COM chaw nres nkoj configuration: Siv GPIO siab impedance hom, txuas ib tug 47K resistor rau ib tug capacitor rau txhua COM, thiab tau txais lub midpoint voltage (1/2 VDD) tom qab RC lim. Teem kom thawb- rub tawm cov zis thaum lub sijhawm luam theej duab, rov kho lub xeev siab impedance thaum tsis luam.
SEG chaw nres nkoj configuration: txais kev thawb- rub tawm hom, inverting lossis hauv -theem nrog COM teeb liab los tswj cov zaub. Piv txwv li, thaum COM scans, yog hais tias ib tug SEG yuav tsum tau muab tso tawm, nws outputs ib inverted voltage; Yog tias nws yuav tsum tau muab tua, tso tawm tib theem voltage.
Voltage divider circuit: Rau 1/3 Bias LCDs, lub resistor divider network (xws li 150K, 10K, 100K, 47K resistor ob peb ua ke) yuav tsum tau siv los tsim 0.5V, 2.5V, thiab 4.5V voltages, xyuas kom meej tias COM chaw nres nkoj outputs ib nrab ntawm lub xeev voltage.
2. Dedicated LCD tswj kev daws teeb meem
Rau cov cuab yeej nyuaj xws li ntau kab qhia thiab kev tswj teeb pom kev zoo, nws raug nquahu kom siv MCUs nrog ua -hauv LCD controllers (xws li Renesas RL78, RA4M1 series). Nws qhov zoo muaj xws li:
Integrated tsim: Muab modules xws li tso saib cov ntaub ntawv sau npe, moos tswj, boost circuits, thiab lwm yam., txo tus naj npawb ntawm peripheral Cheebtsam.
Saj zawg zog configuration: Txhawb ntau yam ua ke ntawm Duty (1/2, 1/3, 1/4, thiab lwm yam) thiab Bias (1/2, 1/3, 1/4, thiab lwm yam) kom hloov mus rau txawv specifications ntawm LCDs.
Kev ua kom zoo zog qis: Los ntawm kev tso tseg lub moos tsis tsim nyog (xws li OSMC sau npe), kev siv hluav taws xob txo qis thiab roj teeb lub neej ntev.
3, Kev Ua Haujlwm Software: Scanning Algorithm thiab Display Control
1. Core scanning algorithm
Cov zaub ntawm ntu code LCD yuav tsum tau ua tiav los ntawm kev tshawb xyuas lub sijhawm, thiab cov txheej txheem raug raws li hauv qab no:
Initialization: Configure MCU tus pin hom (thaum-rub / siab impedance xeev) thiab timer cuam tshuam (xws li 2ms voj voog).
Scanning muaj nuj nqi: hu rau scanning muaj nuj nqi nyob rau hauv lub timer cuam tshuam, hloov lub COM teeb liab ncig thiab hloov kho cov ntaub ntawv SEG. Piv txwv li, 1/4 Lub Luag Haujlwm LCD yuav tsum muaj 8 lub voj voog hu kom ua tiav ib lub thav duab scan (refresh tus nqi ntawm 62.5Hz).
Cov ntaub ntawv buffering: Siv lub cim xeeb video los khaws cov ntsiab lus, thiab hloov cov lej / cov cim rau hauv ntu cov lej los ntawm kev saib lub rooj (xws li tus lej "8" sib raug rau 0x7F).
2. Zaub tswj optimization
Kev hloov kho qhov sib txawv: Kho qhov tsav hluav taws xob los ntawm kev kho qhov Bias resistor voltage divider network lossis MCU ua - hauv boost circuit (xws li Renesas VLCD register).
Los tiv thaiv kua muag mechanism: Rau LCDs nrog TE (synchronous teeb liab) pins, TE pulses raug ntes los ntawm GPIO cuam tshuam kom ua tiav synchronization ntawm cov ntaub ntawv nco thiab refresh; Thaum tsis muaj TE tus pin, lub vijtsam tuaj yeem zam los ntawm kev tsim kua muag los ntawm kev nug cov kab scanning (xws li GetScanline hais kom ua hauv ST7789).
Tsawg zog hom: Hauv hom pw tsaug zog, tag nrho cov COM / SEG pins yog cov zis ntawm qhov qis, thiab lub LCD tsav Circuit Court raug kaw kom txo tau qhov kev siv tam sim no.
4, Kev Ua Lag Luam Kev Lag Luam: Tag Nrho Cov Txheej Txheem los ntawm Kev Tsim Kho rau Kev Tsim Khoom
1. Customized tsim
Qhov kev thov rau ntu code LCD hauv cov cuab yeej muaj ntau yam thiab yuav tsum tau kho raws li daim ntawv thov scenarios
Qhov loj thiab tus naj npawb ntawm ntu: Yog tias cov cuab yeej siv kho mob xav tau kom pom qhov kub thiab txias, lub plawv dhia, thiab lub sijhawm cov ntaub ntawv nyob rau hauv qhov chaw ntawm 40mm × 20mm, yuav tsum muaj lub tswv yim tshiab electrode.
Xim thiab kho qhov muag hom: Cov zaub zoo (dub tom qab nrog cov ntawv dawb) yog qhov tsim nyog rau qhov chaw sab hauv tsev, thaum cov zaub tsis zoo (dawb tom qab nrog cov ntawv dub) txhim kho kev nyeem sab nraum zoov; Semi pob tshab thiab semi reflective hom yog sib xws nrog ob qho tib si backlight thiab reflected lub teeb.
Environmental adaptability: Muaj qib kev ntseeg tau los ntawm -40℃qis-kub pib- nce kev xeem, 85℃high-temperature aging test, thiab 2000 teev tas li teeb pom kev zoo.
2. Kev tsim khoom thiab kev sim
Kev txawj ntse ntau lawm kab: Txais kev lees paub dual ntawm online AOI tshawb pom thiab kev tshuaj xyuas phau ntawv, tag nrho cov txheej txheem los ntawm ITO conductive iav txiav rau siv lead ua sealing yog automated.
Tsav IC sib piv: Rau qis- qhov yuav tsum tau muaj hwj chim, xaiv ultra- cov kev daws teeb meem tsis muaj zog tsav (xws li kev hloov kho tsav ICs los ntawm Xuda Electronics) kom ntev roj teeb lub neej.
Backlight kev koom ua ke: Rau cov cuab yeej uas yuav tsum tau saib thaum hmo ntuj, integrate EL los yog LED backlight modules thiab kho brightness los ntawm PWM dimming (xws li Tesla Model 3's 1024 theem dimming).
