MAX685:双输出(正-负)、DC-DC转换器,用于CCD及LCD

The MAX685 DC-DC converter provides low-noise dual outputs for powering CCD imaging devices and LCDs. This device uses a single inductor to provide independently regulated positive and negative outputs. Integrated power switches are included in a small 24-Pin 4mm x 4mm Thin QFN package to save space and reduce cost. A 16-pin QSOP package is also available. Each output delivers up to 10mA from a +2.7V to +5.5V input voltage range. Output voltages are set independently up to 24V and down to -9V. With a few additional low-cost components, the output voltages can be set at up to 45V and down to -16V. Output ripple magnitude is 30mVp-p. The MAX685 uses a fixed-frequency, pulse-width-modulated (PWM) control scheme at 220kHz or 400kHz to permit output noise filtering and to reduce the size of external components. The frequency can also be synchronized to an external clock signal between 200kHz and 480kHz. The MAX685 has a power-OK indicator output (POK) that signals when both outputs are within regulation. A logic-controlled shutdown completely turns off both outputs and reduces supply current to 0.1µA. The user can also set which output turns on first. The preassembled MAX685 evaluation kit is available to reduce design time.

关键特性
  • Dual Output Using a Single Inductor
  • Low-Noise Output, 30mVp-p Ripple
  • Output Voltages up to 24V and down to -9V (up to 45V and down to -16V with added components)
  • Internal Switches in a Small 24-Pin 4mm x 4mm Thin QFN Package
  • 220kHz/400kHz Fixed-Frequency PWM Operation
  • Frequency Can Be Synchronized to External Clock
  • Power-OK Indicator
  • Selectable Power-On Sequencing
  • 0.1µA Logic-Controlled Shutdown
功能框图
MAX685:典型工作电路
产品应用
  • 便携式摄像机
  • CCD成像装置
  • 数码相机
  • LCD
  • 笔记本电脑
关键参数
Part NumberVIN
(V)
VIN
(V)
VOUT1
(V)
VOUT1
(V)
IOUT1
(A)
Output Adjust. MethodDC-DC OutputsAlternate TopologyOper. Freq.
(kHz)
Switch TypePackage/PinsBudgetary
Price
minmaxminmaxmaxSee Notes
Part NumberVIN
(V)
VIN
(V)
VOUT1
(V)
VOUT1
(V)
IOUT1
(A)
Output Adjust. MethodSwitch TypeDC-DC OutputsOper. Freq.
(kHz)
Package/PinsBudgetary
Price
minmaxminmaxmaxSee Notes
MAX6852.75.52.7240.01Resistor2
Inverting
Step-Up
480Internal
QSOP/16
TQFN/24
$3.83 @1k
MAX6852.75.52.7240.01ResistorInternal2480
QSOP/16
TQFN/24
$3.83 @1k
数据手册DataSheet
英文MAX685.pdfRev 1; 06/2003
开发工具
质量和环境数据
订购型号
型号状况推荐替代产品封装温度RoHS/无铅
MAX685C/D停止供货DICE SALES,;NA引脚;DICE;参考数据资料
MAX685EEE生产中QSOP,;16引脚;30.9mm²-40°C至+85°CRoHS/无铅:否
MAX685EEE+生产中QSOP,;16引脚;30.9mm²-40°C至+85°CRoHS/无铅:无铅
MAX685EEE+T生产中QSOP,;16引脚;30.9mm²-40°C至+85°CRoHS/无铅:无铅
MAX685EEE-T生产中QSOP,;16引脚;30.9mm²-40°C至+85°CRoHS/无铅:否
MAX685ETG停止供货MAX685ETG+TQFN,;24引脚;16.8mm²-40°C至+85°CRoHS/无铅:否
MAX685ETG+生产中TQFN,;24引脚;16.8mm²-40°C至+85°CRoHS/无铅:无铅
MAX685ETG+T生产中QFN;24引脚-40°C至+85°C参考数据资料
MAX685ETG-T停止供货MAX685ETG+TQFN;24引脚-40°C至+85°C参考数据资料
MAX685.pdf MAX685
MAX685.pdf MAX685
MAX685.pdf MAX685
MAX685.pdf MAX685
MAX685.pdf MAX685