Ib, PWM thev naus laus zis txoj cai: Ua raws li kev tswj hwm analog nrog cov teeb liab digital
PWM tswj qhov ci ntsa iab ntawm lub teeb ci LEDs los ntawm kev hloov cov qib siab thiab qis qis thiab kho qhov nruab nrab cov zis hluav taws xob siv lub voj voog ua haujlwm (qhov piv ntawm siab - lub sijhawm rau lub sijhawm). Piv txwv li, ntawm qhov zaus ntawm 1kHz thiab lub voj voog ua haujlwm ntawm 50%, LED ua haujlwm ntawm 50% lub zog kom ua tiav ib nrab lub teeb ci. Nws cov txiaj ntsig tseem ceeb nyob hauv:
Ua tau zoo thiab lub zog-txuag: Piv rau analog dimming (kho qhov ci ntsa iab los ntawm kev hloov tam sim no), PWM tseem tuaj yeem tswj xyuas qhov kub ntawm LED xim kub ntawm qhov ci tsis muaj zog ntxiv.
Tsis yog flicker tsim: Thaum PWM zaus tshaj qhov tseem ceeb flicker fusion zaus (CFFF, txog 60Hz) ntawm tib neeg lub qhov muag, qhov muag flicker yuav raug tshem tawm tag nrho. Cov xwm txheej muaj feem ntau siv ntau zaus tshaj 100Hz kom muaj kev nplij siab thaum lub sij hawm ntev - siv.
Cov lus teb ceev ceev: PWM tuaj yeem ua tiav millisecond qib brightness hloov, hloov mus rau cov ntaub ntawv hloov pauv sai ntawm cov khoom siv khoom lag luam.
2, Hardware Design: Xaiv Logic los ntawm MCU rau Dedicated Driver Chip
1. MCU direct drive daws
Haum rau kev lag luam cov twj paj nruag nrog qis ntu suav thiab cov duab yooj yim (xws li cov twj paj nruag monochrome). Siv STM32F031C6T6 ua piv txwv:
COM chaw nres nkoj configuration: Txais GPIO siab impedance hom, ua ke nrog RC filtering circuit los tsim midpoint voltage (xws li 2.5V), kom tsis txhob DC bias ua rau LCD laus.
SEG chaw nres nkoj configuration: thawb- rub tawm hom, inverted nrog COM teeb liab los tswj cov zaub. Piv txwv li, thaum COM scans, SEG yuav tsum tau tso tawm tawm ib theem siab, thiab vice versa outputs theem qis.
Voltage divider circuit: Tsim 1/3 Bias voltage los ntawm lub network resistor (xws li 150K, 10K, 100K, 47K ua ke) kom ruaj khov midpoint voltage tso tawm los ntawm COM chaw nres nkoj thaum nyob hauv lub xeev muaj zog.
Qhov zoo: Tus nqi qis, thaj chaw PCB me me, tsim nyog rau cov kab ke nrog cov peev txheej tsawg.
2. Dedicated tsav tsheb nti daws
Rau cov cuab yeej nyuaj xws li ntau kab lus thiab cov ntsuas ntse nrog kev tswj lub teeb, nws raug nquahu kom siv MCU nrog ua -hauv LCD maub los (xws li Renesas RL78 / RA4M1 series):
Integrated design: Integrate display data registers, clock control, and boost circuits (xws li VLCD registers) kom txo tau cov khoom peripheral.
Saj zawg zog configuration: Txhawb ntau yam ua ke ntawm Duty (1/2, 1/3, 1/4) thiab Bias (1/2, 1/3, 1/4) kom hloov mus rau txawv specifications ntawm LCDs.
Kev siv hluav taws xob tsawg: 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.
Daim ntawv thov: Lub LCD maub los ntawm Renesas RA4M1 tuaj yeem tsav 4 × 40 ntu LCDs, thaum tswj lub teeb ci ntsa iab los ntawm PWM modules kom ua tiav kev tswj hwm kev tswj hwm ntawm cov zaub thiab teeb pom kev zoo.
3. Kev Ua Lag Luam Kev Ua Lag Luam: Tag Nrho Cov Txheej Txheem Ua kom zoo los ntawm kev tsim qauv mus rau pawg ntau lawm
1. Customized tsim
Qhov kev thov rau LCD hauv kev lag luam twj paj nruag muaj ntau haiv neeg thiab yuav tsum tau kho raws li cov ntawv thov scenarios
Qhov loj thiab tus naj npawb ntawm ntu: Yog tias cov khoom siv kho mob xav tau kom pom qhov ntsuas kub, 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.
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 mus li teeb pom kev zoo.
Optical hom: Cov zaub zoo (dub tom qab nrog cov ntawv dawb) yog qhov tsim nyog rau qhov chaw nyob 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.
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 twj paj nruag uas yuav tsum tau pom thaum hmo ntuj, integrate EL lossis LED backlight modules thiab kho qhov ci ci los ntawm PWM dimming (xws li Tesla Model 3's 1024 theem dimming).
