Catalyst 公司的CAT4201是350mA高效率降压LED驱动器，它能驱动大电流LED.

      CAT4201的工作电压高达28V，和12V和24V系统兼容，功率效率高达94%.本方案介绍了CAT4201的主要性能和应用，以及CAT4201评估板的电路图和所用元器件清单(BOM).

      CAT4201 350mA High Efficiency Step Down LED Driver

      The CAT4201 is a high efficiency step-down converter optimized to drive high current LEDs. A patent-pending switching control algorithm allows highly efficient and accurate LED current regulation. A single RSET resistor sets the full scale LED string current up to 350mA from supplies as high as 28V.

      The switching architecture of the CAT4201 results in extremely low internal power dissipation allowing the device to be housed in a tiny package without the need for dedicated heat sinking. The device is compatible with switching frequencies of up to 1MHz， making it ideal for applications requiring small footprint and low value external inductors.

      Analog dimming and LED shutdown control is provided via a single input pin， CTRL. Additional features include overload current protection and thermal shutdown. The device is available in the low profile 5-lead thin SOT23 package and is ideal for space constrained applications.

      主要特性:

      LED drive current up to 350mA
      12V and 24V system compatible
      Handles transients up to 40V
      Single Pin Control and Dimming function
      Power Efficiency up to 94%
      Drives LED strings of up to 20 volts
      Open and short LED protection
      Parallel configuration for higher output current
      RoHS-compliant TSOT-23 5-lead package

      应用:

      12V and 24V Lighting Systems
      Automotive and Aircraft Lighting
      General lighting
      High Brightness 350mA LEDs

      图1.CAT4201简化的方框图.
      CAT4201 LED 驱动器评估板外形:

      Fig 2. CAT4201EVAL2 评估板电路图
      CAT4201EVAL2 评估板材料清单(BOM):

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