MAX1839:宽亮度范围CCFL背光控制器

业内首款完全集成的CCFL逆变控制器,具有较宽的调光范围、高性能指标和完备的故障保护功能

The MAX1739/MAX1839 fully integrated controllers are optimized to drive cold-cathode fluorescent lamps (CCFLs) using the industry-proven Royer oscillator inverter architecture. The Royer architecture provides near sinusoidal drive waveforms over the entire input range to maximize the life of CCFLs. The MAX1739/MAX1839 optimize this architecture to work over a wide input voltage range, achieve high efficiency, and maximize the dimming range. The MAX1739/MAX1839 monitor and limit the transformer center-tap voltage when required. This ensures minimal voltage stress on the transformer, which increases the operating life of the transformer and eases its design requirements. These controllers also provide protection against many other fault conditions, including lamp-out and buck short faults. These controllers achieve 50:1 dimming range by simultaneously adjusting lamp current and "chopping" the CCFL on and off using a digitally adjusted pulse-width modulated (DPWM) method. CCFL brightness is controlled by an analog voltage or is set with an SMBus™-compatible two-wire interface (MAX1739). The MAX1739/MAX1839 drive an external high-side N-channel power MOSFET and two low-side N-channel power MOSFETs, all synchronized to the Royer oscillator. An internal 5.3V linear regulator powers the MOSFET drivers and most of the internal circuitry. The MAX1739/MAX1839 are available in space-saving 20-pin QSOP packages and operate over the -40°C to +85°C temperature range.

关键特性
  • Fast Response to Input Change
  • Wide Input Voltage Range (4.6V to 28V)
  • High Power-to-Light Efficiency
  • Minimizes Transformer Voltage Stress
  • Lamp-Out Protection with 2s Timeout
  • Buck Switch Short and Other Single-Point Fault Protection
  • Integrated Royer MOSFET Drivers Reduce Transformer Pin Count
  • Buck Operation Synchronized to Royer Oscillator
  • Synchronizable DPWM Frequency
  • Pin-Selectable Brightness Control Interface
  • SMBus Serial Interface (MAX1739)
  • Analog Interface (MAX1739/MAX1839)
功能框图
MAX1739、MAX1839:功能框图
产品应用
  • LCD显示器
  • 掌上电脑
关键参数
Part NumberVIN
(V)
VIN
(V)
TopologyChannelsDimming InterfaceFreq.Package/PinsOper. Temp.
(°C)
Budgetary
Price
minmaxSee Notes
MAX18394.628Royer Oscillator1
Analog
DPWM
Resonant
QSOP/20
-40 to +85$4.26 @1k
数据手册DataSheet
英文MAX1739-MAX1839.pdfRev 1; 04/2001
订购型号
型号状况推荐替代产品封装温度RoHS/无铅
MAX1839EEP停止供货MAX8759ETI+QSOP,;20引脚;54.2mm²-40°C至+85°CRoHS/无铅:否
MAX1839EEP+NRNDMAX8759ETI+QSOP,;20引脚;54.2mm²-40°C至+85°CRoHS/无铅:无铅
MAX1839EEP+T生产中MAX8759ETI+QSOP;-40°C至+85°C参考数据资料
MAX1839EEP-T停止供货MAX1839EEP+TQSOP;20引脚-40°C至+85°C参考数据资料
MAX1739-MAX1839.pdf MAX1839
MAX1739-MAX1839.pdf MAX1839
MAX1739-MAX1839.pdf MAX1839