Acer AC901 User manual

19 -inchCRTMonitor
Acer AC901
S

AC901
Page 5
2 Product Specifications
2-1Specifications
Note:Above specificationsaresubjecttochange withoutpriornotice.
Picture Tube 19-inch, (18-inch visual image area) sloted mask, 90 degrees deflection, dot type black matrix, medium short persistence
phosphor, dark tint, non-glare/ anti-static screen,
0.26 mm dot pitch
Scanning Frequency VGA, Super VGA, 1024x768@75/85 Hz, 1280x1024@85 Hz
Maximum Resolution 1600 dots (H) x 1200 lines (V) @75Hz refresh rate
Display Area 350 mm (H) x 262 mm (V) typical
Display Characters 80 char. x 60 rows on a 10 x 10 matrix
Display Colors Analog
Input Unlimited Colors
Synchronizatin Signals Separate Sync: horizontal/vertical, TTL, positive or negative
Synchronization
Frequencies Horizontal : 30 to 96 kHz Vertical : 50 to 160 Hz
Signal Connectors 15-pin, D-shell connector
Video Signals Analog : 0.7 Vp-p, RGB positive
Power Input 120 Watts (maximum) AC rated voltage, 100VAC to 240VAC,
200VAC to 240VAC for PNST/PNSL models
Misconvergence Center Area : <0.3 mm; Corner Area : <0.4mm
User Controls
Power On/Off, Contrast, Brightness, Horizontal Size,
Horizontal Position, Vertical Size, Vertical Position,
Pincushion, Trapezoid, Pin Balance, Parallelogram, Rotation,
Color temperature, Language, Display Frequency, Degauss,
Recall, H. Moire, V. Moire
Service Controls PWB-1596/1598 : power voltage adjust (VR801)
focus 1 , focus 2
Preset Modes 10 (see Table 2-2. Timing Chart)
Environmental
Considerations Operation temperature : 5oC to 35oC ambient Operation Humidity : 20% to 80% ambient
Storage temperature : -40oC to 65oC ambient
Storage Humidity : 5% to 95% (non-condensing)
Altitude : up to3000m above sea level

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2-2SignalCablePinConnections
Table2-1.SignalCablePinAssignment
Pin Signal Pin Signal
1Red video 9+5V
2Green video 10 Digital Ground
3Blue video 11 Ground
4Ground 12 SDA
5* Ground 13 H-Sync
6Red ground 14 V-Sync/VCL
7Green ground 15 SCL
8Blue ground
Note:*Thispinisusedforselftestdetection.Connectthispintogroundatthe PCend.

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2-3Timing Chart
Thissectiondescribesthe timingsthatthe computerindustryrecognizesasstandardforcomputer-generated
videosignals.
Table2-2.Timing Chart
Seperate Sync
Horizontal
Video
C
D
E
Sync
A
B
F
Vertical
Video
I
J
Sync
G
H
L
K
H.Parameters:
A:Period B:Blanking Time
C:Sync WidthD:BackPorch
E:Active TimeF:FrontPorch
V.Parameters:
G:Period H:Blanking Time
I:Sync WidthJ:BackPorch
K:Active TimeL:FrontPorch
Mode 1 2 3 4 5 6 7 8 9 10
H. Dots 640 720 640 832 800 1152 1024 1600 1280 1600
V. Dots 480 400 480 624 600 870 768 1200 1024 1200
H-freq (kHz) 31.47 37.927 43.27 49.725 53.67 68.681 68.67 75 91.146 93.75
Sync Polarity - - - - +-+-+ +
A period us 31.78 26.366 23.11 20.11 18.631 14.561 14.561 13.333 10.971 10.667
B Blanking us 6.356 6.085 5.33 5.586 4.409 3.04 3.725 3.457 2.844 2.765
C Sync us 3.81 2.028 1.556 1.117 1.138 1.28 1.016 1.185 1.016 0.948
D B.P. us 1.907 3.042 2.22 3.91 2.702 1.44 2.201 1.877 1.422 1.501
E Active us 25.42 20.282 17.78 14.524 14.222 11.52 10.836 9.877 8.127 7.901
F F.P. us 0.636 1.014 1.556 0.559 0.569 0.32 0.508 0.395 0.406 0.316
V-freq (Hz) 59.94 85 85 74.55 85 75.062 84.99 60 85 75
Sync Polarity -+- - +-+-+ +
G Period ms 16.68 11.759 11.76 13.414 11.756 13.322 11.765 16.667 11.761 13.333
H Blanking ms 1.43 1.213 0.67 0.864 0.578 0.656 0.582 0.667 0.527 0.533
I Sync ms 0.064 0.079 0.069 0.06 0.056 0.044 0.044 0.04 0.033 0.032
J B.P. us 1.02 1.107 0.578 0.764 0.503 0.568 0.524 0.613 0.483 0.491
K Active us 15.25 10.546 11.09 12.549 11.179 12.667 11.183 16 11.235 12.8
L F.P. us 0.35 0.026 0.023 0.04 0.019 0.044 0.015 0.013 0.011 0.011

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2-4PowerSaving Function
Note:The monitorwill bedriven into“PowerSaving”modebythe controlsignalfromthe display
controller,asindicatedbythe amber-colorpowerLED.
Table2-3.PowerSaving Function
State Power
Consumption LED
Light
ON <120 watts Green
Active
OFF <3 watts Amber
The powersaving stateswill bekeptuntil acontrolsignalhasbeen detectedorthe keyboardormouseisactivated.
The recoverytimefromActive OFF statebacktoONstateisaround10seconds.
2-5TCOVersion (Optional)
The monitormeetsthe TCO99,NUTEKenergy saving,electricandmagneticfieldrequirements.
2-5-1TCO99 Version (Optional)
The emissionfrommagneticandelectricfieldmustcomplywiththe limitsspecifiedbythe SwedishBoard
forMeasurementandTesting,commonlyknownasMPR1990 recommendations.Theselimitsare
summarizedinthe Table2-4.
Table2-4.TCO99 Requirements
VLF/TCO ELF/TCO
Magnetic Field 25 nT 200 nT
Electric Field 1 V/m 10 V/m
Frequency Range 2~400 kHz 5~2000 Hz
Value RMS RMS
Distance 30 cm 30 cm
Electrostatic
Potential +/- 500 V +/- 500 V

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The monitorisdesignedwithselectedCRTandcarefullyroutedwiresaroundCRT,makesureexactlythe
samerouting schemeisusedwhen doing CRTreplacement.
The TCO99 schemeisforinternationalandenvironmentallabelling ofpersonalcomputers.The labelling
schemewasdevelopedasajointeffortbythe TCO(The SwedishConfederationofProfessionalEmploy
ees),Naturskyddsforeningen (The SwedishSocietyforNatureConservation)andNUTEK(The National
BoardforIndustryandTechnicalDevelopmentinSweden).
1)`Scope
TCO99 touchesonergonomicqualities,emissions(electricalandmagneticfields),energy efficiency and
ecology (withdemandsforenvironmentaladaptationforboththe productandthe productionprocessesat
the manufacturing plant).
2)EnvironmentalRequirements
The monitorabidesbythe environmentaldemandsconcerning restrictionsonthe presence anduseof
heavy metals,brominatedandchlorinatedflameretardants,CFCs(freons),andchlorinatedsolvents,
among otherthings.The monitorisalsorecyclable.
3)Energy Requirements
The monitoralsofollowsthe energy requirementsthat, afteracertainperiod ofinactivity,the monitor
shall reduce itspowerconsumptiontoalowerlevelinone ormorestages.
4)Others
The monitormeetsthe strictenvironmentaldemandsforthe reductionofelectricandmagneticfields,
physicalandvisualergonomicsandgood usability.
Table2-5.TCO99 VisualErgonomics
Feature Standard Description
Linearity 1% or less Difference in length of columns or rows compared to the
corresponding lengths through the center of the monitor.
Display Luminance 100 cd/m2 (at least)
Luminance
Uniformity 1.5:1 or less The ratio is between the max to min luminance within the whole active area.
Color temperature
variation ? u'v'0.01≦
Reclections from
casing 20%/30glass≧ ≦ The reflection ration is on cabinet & table.

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3 Control Location and Functions
3-1FrontPanel
3-2FrontPanelKeysFunctions
1.FunctionKey:Display the mainmenu,andexitthe adjustmentscreen andsave adjustments.
2.DecreaseKey:Scroll across mainmenu,highlighting controltobeadjusted.Decreasevalue ofselected
control.Togglebetween ContrastandBrightness adjustmentscreens.
3.IncreaseKey:Scroll across mainmenu,highlighting controltobeadjusted.Increasevalue ofselected
control.Togglebetween ContrastandBrightness adjustmentscreens.
4.SelectKey:Press once todisplay adjustmentscreen.Press again,forsomecontrols,totogglebetween
controlsshowninpairsonmainmenu.
5.PowerLED:Display differentmodes(ON,OFF)ofthe monitorbyshowing differentcolorforeach
mode.
6.PowerON/OFF:Toturnthe monitorON andOFF.
3-3AdjustmentProcedure
1.Press (6)key toturnonthe monitor.
2.Atnormalcondition,press (1)onthe frontpaneltoactivatethe on-screen manager(OSM)menu.
3.Toselectausercontrol,press (2)or(3)key repeatedlyuntil the controlishighlighted.
4.Toadjustthe value foraparticularcontrol,press (4),then press the (2)or(3)key toobtainthe desired
value.Thereareafewparametersthatdo notrequireany adjustment, likeManualDegauss,Memory
Recall.
5.Somecontrolsaregroupedinpairsonthe mainmenu.Press (4)key totogglebetween them.
6.Tosave youradjustmentsandexitscreen,press (1)key.The menu will automaticallyclearoutfromthe
screen ifnokeysarepressedwithin30 seconds.
Note:Toenterthe “InternalAdjustment”mode,press (1)&(4)keyssimultaneouslythen press (6).
(1) Function Key
(2) DecreaseKey
(3) IncreaseKey
(4) Select Key
(5) Power LED
(6) Power ON/OFF
(1) (2) (3) (4) (5) (6)
1
2

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4 Operation Theory
Thisisafullydigitalcontrolledmulti-sync colormonitorthatiscompliantwithDDC1/2BPlug andPlay
VESAstandardandoffersthe following mainfeatures.
4-1MainFeatures
1.Simplifieddesign withminimumcomponents.
2.The NOVATEKNT68P65AU processor-- thathasI2Cbuscontrolledgeometriccorrection,contrastand
brightness-- offersthe functionsfor:(a)Contrast, (b)Brightness,(c)H-size,(d)H-position,(e)V-size,(f)
V-position,(g)Pincushion,and(h)Trapezoid,(i)PinBalance,(j)Parallelogram.
Inaddition,italsooffersmorefunctionsas:(a)Sync.processor,I/PandO/P,(b)Mute,(c)Powersaving
off, (d)Powersaving override,(e)DDC2B,(f)I2CBusforauto-alignmentthrough signalcable(g)CS
switching forlinearityandsizecompensation,(h)High voleage adjustment, (i)G2voltage adjustment.
3.Storesupto10factorypresetmodesandoffers6usermodes.Thereare18 functioniconsinOSD.They
arecontrolledby
1
2
keysonthe frontpanel.
4.PowerfulPHILIPS TDA4841 andTDA4863 presentthe following usefulfunctions:(a)Pincushion,(b)
Trapezoid,(c)V-Position,(d)V-Size,(e)Vertical’s“C”and“S”correction--factoryadjust,(f)Pincushion’s
V.positioncorrection,(g)Cornercorrection-- factoryadjust, (h)Pincushionunbalance correction--
factoryadjust, (i)Parallelogramdistortion-- factoryadjust, (j)Moirecancellation,(k)X-ray protection,
and(l)Full horizontalandverticalautosync capability.
5.Softwarecontrolledautoshutoff functionactivatediffH<=29 kHzandfH>=96 kHz.
6.Full range AC inputandsimplifiedline filterdesign.
4-2MicrocontrolSection
1.ThismonitorusesNOVATEKNT68P65AU CPU.Itcontainsa8-bitCPUcore,256 bytesofRAMused
asworking RAMandstackarea,24k bytesofOTP ROM,14-channel8bitPWMD/Aconverter,2-
channelA/Dconvertersforkey detectionsaving I/Opins,internalH.sync andV.sync signalsprocessor
providing modedetection,andan I2Cbusinterface.When H/Vsync through D-Subsignalcableenterpin
41 andpin42,the CPUperformsfrequency /polaritydetectionandcalculateandsendtoH/Vsync OUT.
Then CPUreadsthe datafromI703andtransfertodevice 4841andsomeDACinCPU,above operation
takesabout500 ms.
2.Thereallows10factorypresetmodesand6usermodes.Thereare8functions,Contrast, Brightness,H.
Size,H.Position,V.Size,V.Position,Pincushion,andTrapezoid,all controlledbyOSDiconwhich can
beadjustedbyuser.
3.The pin25 andpin26areusedforATE function.When CPUreceivesC6asslave address,itwill operate
inATE modewhich isusedforauto-alignment. Afteralignmentthe datawill bestoredinI703.
4.The usercontrolparametersareselectedbyOSDicons,through
1
2
keys,they aredetectedby
sensing the voltage through R710,R759,R713,R714,R709,R711,R760 topin16 and17 ofI701.
4-3Deflection Section
1.I2C-- autosync deflectioncontrollerisTDA4841.
2.The TDA4841 isahigh performance andefficientsolutionforautosync monitors.All functionsare
controllablebyI2Cbus.SDA andSCLsignalscoming frommicroprocessorfeedtopin19 andpin18 to
controlall functions.

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4-3-1 Horizontal Section
1.The oscillatorisdriven bythe currentsinR472 andR468.Theminimumoscillatorfrequency isdetermined
byR472 andthe maximumfrequency isdeterminedbyR468.
2.Horizontalsync goesintopin15through R494.Andhorizontalflybackpulsegoesintopin1through R479
andbypass filterC445 fromEmitterofQ407 andC412,C433,C411,R419,C456,R421,D413 forAFC
loop.
3.Horizontaldriver(pin8)outputtoQ401 viaC401,Q401 switching todrive T401 provideIB1/IB2current
then turnon/off Q402 andswitching the yokecurrent.
4-3-2Vertical Section
1.Verticalsync goesintopin14 through R493.
2.The free running frequency isdeterminedbyR470 andC442.
4-3-3Vertical O/Psection
1.The differentialoutputcurrentsfrompin13 ofVout1andpin12 ofVout2can bedirectlycoupledtothe
verticaldeflectionboosterpin3andpin2ofTDA4863.
2.TheTDA4863 hastwooutputstageswhich arecurrentdriven inoppositephaseandoperateincombination
withthe deflectioncoil inahalfbridge configuration.
3.ThisICispoweredbythree setsofpositive voltage.(+13Vatpin1,37Vatpin8,-13Vatpin6)
4-3-4E-W/Trapezoid and H. Width Controls
1.The scan currentisdeterminedbyB+(the voltage ofC413)thatisobtainedfromstepdowncircuit
output. StepdowncircuitincludeQ404,T402,D407.
2.I401 TDA4841 pin6(BDRV)will drive the stepdowncircuittochange H.width.
3.EWDRV(pin11)providesacompleteEWdrive waveformincluding parabola,cornerandtrapezoid
correctionandfeedtoBIN(pin5ofI401)togetagood controlforpincushion/trapezoid/corner.
4.The topandbottomcornercorrectioncan beadjustedseperately.
4-3-5X-Ray Protection
1.ToavoidX-ray hazard,aDC voltage generatedatpin6ofFBTandrectifiedbyD107,C111 anddivided
byR476,R477 andR478 comeintopin2ofTDA4841.
2.Ifthisvoltage ishigherthan 6.39 V,then TDA4841 will beactivatedtofloatHUNLOCK(pin17),H.
DRV(pin8),BDRV(pin6),VOUT1(pin12),VOUT2(pin13).Afterthatall deflectioncircuitstop
working.
4-3-6Blanking and Brightness
1.The verticalblanking signalcomesfromI401 pin16 andverticalsync.Thesetwopulsescombine into
Q542 andQ541.ThissignalfeetsintoT501 pin24.
2.Inprotectionmodeoroutofrange ormodechange mutesignalwill turnhigh andturnonQ107.
G2voltage will drop from600Vto250V.
3.The brightness iscontrolbyI2Cbus.The outputpinsareI501 pin14,pin15,pin16.

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4-3-7ContrastSection
1.ContrastiscontrolledbyI701 through I2CbustoI501 (LM1267)directly.
2.Beamcurrentisdetectedthrough T101 (FBT)pin7,D106,C109,Q102,R108,R121,R122 tocontrol
I501 pin22 voltage.When I501 pin22 voltage dropsbelow5V,the ABLfunctionwill happen.
4-3-8Dynamicfocuscircuitry
The dynamicfocusisappliedtoimprove the cornerfocusperformance,itincludeshorizontalandvertical
dynamicfocus.
1.VerticaldynamiccomesfromI401 pin32 andisamplifiedthrough C105,Q101,C137,andfeedtoFBT
dynamicfocuspinsR133,R132,Q101.
2.Thisamplifierneed200Vvoltage supply,itcomesfromFBTpin8andrectifiedthrough L102,D101,and
C102.
4-4PowerSupplySection
4-4-1AC Rectifier
The circuitcan accept90 Vto264 VAC inputthrough D801 bridge diodesandC808filtering togetDC 126
V~364 VforpowerconversioninT802.
4-4-2Line Filter
ItconsistsofC801,C802,C803,C816,C820,C823,T801,T804 andmeetsEMIregulation.
4-4-3PowerLEDStatus
1.The LEDhas3leadswithcommoncathodetoemitgreen andambercolorlightfordifferentpower
saving states.
2.Normal:Green light
3.Off Mode:Amberlight
4-4-4 Auto Degaussing
When S801 turnson,pin27 ofI701 will sendasignaltoQ802 andturnsonRL801 fordegaussing.After4
seconds,itwill turnoff RL801 automatically.
4-4-5 PWMControl
1.StartUp
The I801 (KC3843B)getspowerfromR846,Q821,R849,R848,D826,D828,D822 andpin7voltage
reaches8Vforstarting up.The I801 startsoscillationat22 kHz,sawtoothonpin4andpin6outputto
drive Q803/T802.Once Q803 switching on,D806,C804 setupan 15 VtokeepI801 working through
D821 auxiliaryvoltage.
2.Regulation
The DC O/Pvoltage isproportionaltothe auxiliaryvoltage,soI801 pin2sensesthe feedbackvoltage
fromthe dividerR802,R823,VR801 andR820tocomparewiththe built-in2.5voltsreference voltage for
erroramplifieroperation.Finallypin6can modulatethe differentdutycyclebyVR801 setting toachieve
regulationpurpose.