led背光技术的发展与挑战

,LED BLUDriving and Challenge,Outline,LED to CCFL ReplacementLED backlight benefits analysisCCFL/LED market share trendSmall & Middle Size Driving TopologyLED notebook/NetbookLED monitorLow-end displayLED TV Driving TopologyOB LED Driver Roadmap Q&A,TV Products Innovations,Internet Connectivity,3DDisplay,HumanInterface,LEDBacklight,TV Products Innovations,LED backlight is very hot,LED Type,White Light,Current Capability Standard LED - drive current 110%) Light weight and thin profile,Power Saving of LED BLU,Low drive voltage to ensure safety operation The relationship between LED intensity and drive current is liner Lower current is operated to perform the same brightness level that CCFL module Power saving of 3050% of CCFL power consumption,Local Dimming of TV LED BLU,NTSC cover CCFL 78%, WLED 80%, RGB LED 110%),Wide Color Gamut,NB PC,LCD MNT,LCD TV, Power Saving Light weight Thin profile Small cost premium, None, Power Saving Dynamic BLU control, Cost Reliability Huge LED Amount Thermal compensation, Power Saving Thin profile, Cost Input/output interface,Advantage,Challenge,LED BLU Market Potential,Application,High,Low,LED BLU Market Share,Samsung MP LED TV at 2009, Q2Kick off LED TV market Low cost Edge type become main stream Help to rise the share rate from CCFL Power saving features Easy to meet EPA5.0 Will break 50% share 2012,Source: Display Search,LED Driving Topology-NB,15” panel for example6 strings, 10 LED per string 20mAVout 33V, Pout 4W,OB3360 FeaturesBuild-in 60V MOSFET8 string outputWith 60mA current capability per string160K/320K/620K/1.2MHz frequency0100% wide range dimming3% channel to channel current matching,LED Driving Topology-MNT,24” panel for example (1)12 strings, 15 LED per string 20mAVout 50V, Pout 12W,OB3362 Features12 string outputWith 60mA current capability per string150500kHz frequency0100% wide range dimming3% channel to channel current matching,24” panel for example (2)12 strings, 15 LED per string 20mAVout 33V, Pout 4W,parallel connection to support larger current application,LED Driving Topology-Low End Display,OB337X0.2V reference benefits efficiencyInternal burst and external PWM dimmingOutput over voltage protectionOB3372:Boost,DIP8, built in 60V MOSFETOB3370N:Boost, SOP8, ControllerOB3370P:Buck, SOP8, Controller,26” panel for example (2)Single string, 400mAVout 40V, Pout 16W,LED vs. CCFL Cost Comparison,Q3, 2010,$USD,premium 28%,premium 41%,premium 61%,premium 43%,LED TV Market Share Growth,Source: Display Search,LED Backlight for Large Size TV Panel,Direct type with Local dimming,Direct type without Local dimming,Edge type backlight,High Performance,Slim Profile,RGB LED / White LED,White LED,RGB & Local dimming has power saving and high-CR feature High-end use Edge type solution has low cost feature Main stream,Direct Backlight:Better emissionAllowing independently dimming block by block,Edge Backlight:Allowing slim designFewer LED number and lower cost,LED TV Cost Down Trend,Direct type,Edge type,Advanced edge type,Advanced edge type,40 inch LED TV,LED TV Driving Topology,OB3376Dual channel boost controller150/300kHz switching frequencyMulti chip sync.Cost effective,42” panel for example4 strings150mA per stringVout 150V, Pout 90W,LED TV Power Optimize,Current Solution,Optimized Solution,Reduce DC/DC Booster（Cost）Efficiency improvement,Headroom voltage feedback for efficiency and thermal improvement,On-Bright LED TV Total Solu