MAX1848:白光LED升压型转换器,SOT23封装

电流调节升压转换器,用于白光LED供电,可保持一致亮度

The MAX1848 drives white LEDs with a constant current to provide backlight in cell phones, PDAs, and other hand-held devices. The step-up converter topology allows series connection of the white LEDs so that the LED currents are identical for uniform brightness. This configuration eliminates the need for ballast resistors and expensive factory calibration. Other benefits include greater simplicity, lower cost, higher efficiency, and greater reliability. This step-up PWM converter includes an internal, high-voltage, low RDSON N-channel MOSFET switch for high efficiency and maximum battery life. A single analog voltage Dual Mode™ input provides a simple means of brightness adjustment and on/off control. Fast 1.2MHz current-mode PWM control allows for small input and output capacitors and a small inductor while minimizing ripple on the input supply/battery. Programmable soft-start eliminates inrush current during startup. The MAX1848 is available in space-saving 8-pin thin QFN (3mm x 3mm) and 8-pin SOT23 packages.

关键特性
  • Constant Current Regulation for Uniform Illumination
  • High 87% Efficiency
  • Analog or Logic Control of LED Intensity
  • 0.8W Output Power with Internal High-Voltage MOSFET Switch
  • Small, Low-Profile External Components
  • 2.6V to 5.5V Input Range
  • 13V Maximum Output with Overvoltage Protection
  • Optimized for Low Input Ripple
  • Programmable Soft-Start
  • 0.3µA Shutdown Current
  • Small 8-pin Thin QFN (3mm x 3mm) and 8-Pin SOT23 Packages
MAX1848:典型应用电路
MAX1848:典型应用电路
应用
  • 蜂窝电话/智能电话
  • 电子书与亚笔记本电脑
  • PDA、掌上电脑与无线手持装置
  • 白色LED显示器背光
数据手册DataSheet
语言下载文件备注
英文MAX1848.pdfRev 2; 09/2005
关键参数
Part NumberBattery InputRegulation TopologyMax. No. of LEDsLED ChannelsLED ConfigurationILED per Channel
(A)
Dimming RatioDimming ControlVCURR_SENSE
(mV)
POUT
(W)
VIN
(V)
VIN
(V)
ICC
(mA)
LED String Volt.
(V)
Oper. Freq.
(kHz)
Package/PinsBudgetary
Price
maxmaxminmaxmaxmaxSee Notes
MAX18481-Cell Li+Inductor Based61Series0.0620Analog750.82.65.52121200
  • SOT/8
  • TDFN-EP/8
$1.32 @1k
开发工具
技术资料
质量和环境数据
相关产品
  • MAX1698:高效率、升压型稳流器,用于LED驱动
订购型号
型号状况推荐替代产品封装温度RoHS/无铅
MAX1848EKA-T停止供货SOT,;8引脚;9mm²-40°C至+85°CRoHS/无铅:否
MAX1848ETA+生产中TDFN-EP,;8引脚;9.6mm²-40°C至+85°CRoHS/无铅:无铅
MAX1848ETA+T生产中TDFN-EP,;8引脚;9.6mm²-40°C至+85°CRoHS/无铅:无铅
MAX1848ETA-T停止供货MAX1848ETA+TTDFN-EP,;8引脚;9.6mm²-40°C至+85°CRoHS/无铅:否
MAX1848.pdf MAX1848
MAX1848.pdf MAX1848
MAX1848.pdf MAX1848
Important Design Considerations for Digital Thermometers MAX1416
Important Design Considerations for Heart-Rate and Fitness Monitors MAXQ622
Driving White LEDs in Clamshell Phones MAX4625
Light Is On When Power Is Out MAX9021
Driving LEDs in Battery-Operated Applications: Controlling Brightness Power Efficiently MAX8596
Powering Six White LEDs with High Efficiency Using the MAX1848 MAX1848
Powering Four White LEDs with High Efficiency Using the MAX1848 MAX1848
Feedback Circuit Enhances Efficiency of Boost-Converter Current Source MAX1698
MAX1848.pdf MAX1848
MAX1848.pdf MAX1848