LT1932

LT1932恒流ThinSOT封装的DC / DC LED驱动器

特点

• Up to 80% Efficiency 高达80％的效率
• Inherently Matched LED Current 固有匹配的LED电流
• Drives Five White LEDs from 2V从2V驱动五个白光LED
• Drives Six White LEDs from 2.7V从2.7V驱动6个白光LED
• Drives Eight White LEDs from 3V驱动器从3V八白光LED
• Adjustable Control of LED Current 可调的LED电流控制
• Disconnects LEDs In Shutdown在关机断开的LED
• 1.2MHz Fixed Frequency Switching 1.2MHz的固定开关频率
• Uses Tiny Ceramic Capacitors使用小型陶瓷电容
• Uses Tiny 1mm-Tall Inductors采用微型1MM-高层电感
• Regulates Current Even When V _IN > V _OUT即使调节电流的V _{OUT IN>} V
• Operates with V _IN as Low as 1V与V工作电压可低至1V
• Low Profile (1mm) ThinSOT™ Package低调（1毫米）采用ThinSOT™封装
• 描述 The LT®1932 is a fixed frequency step-up DC/DC converter designed to operate as a constant-current source. LT®1932是一个固定频率升压型DC / DC变换器设计工作作为一个恒定电流源。 Because it directly regulates output current, the LT1932 is ideal for driving light emitting diodes (LEDs) whose light intensity is proportional to the current passing through them, not the voltage across their terminals.因为它直接调节输出电流，LT1932是驱动发光二极管（LED）的光强度成正比，通过它们的电流通过，而不是在其终端电压的理想选择。

  With an input voltage range of 1V to 10V, the device works from a variety of input sources. 1V至10V输入电压范围，设备可以从各种输入源。 The LT1932 accurately regulates LED current even when the input voltage is higher than the LED voltage, greatly simplifying battery-powered designs. LT1932准确地调节LED电流，即使在输入电压高于LED的电压，大大简化了电池供电的设计。 A single external resistor sets LED current between 5mA and 40mA, which can then be easily adjusted using either a DC voltage or a pulse width modulated (PWM) signal.单个外部电阻设定LED的电流5mA电流40毫安的，然后可以很容易地使用一个直流电压或脉冲宽度调制（PWM）信号调整。 When the LT1932 is placed in shutdown, the LEDs are disconnected from the output, ensuring a quiescent current of under 1µA for the entire circuit. LT1932被放置在关机时，LED的输出断开，以确保整个电路下1μA静态电流。 The device's 1.2MHz switching frequency permits the use of tiny, low profile chip inductors and capacitors to minimize footprint and cost in space-conscious portable applications.设备的1.2MHz的开关频率允许使用纤巧，低调的片式电感器和电容器，以尽量减少占用空间敏感的便携式应用和成本。

• 应用

  • Cellular Telephones蜂窝电话
  • Handheld Computers掌上电脑
  • Digital Cameras数码相机
  • Portable MP3 Players便携式MP3播放器
  • Pagers寻呼机