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.
语言 | 下载文件 | 备注 |
---|---|---|
英文 | MAX1848.pdf | Rev 2; 09/2005 |
Part Number | Battery Input | Regulation Topology | Max. No. of LEDs | LED Channels | LED Configuration | ILED per Channel (A) | Dimming Ratio | Dimming Control | VCURR_SENSE (mV) | POUT (W) | VIN (V) | VIN (V) | ICC (mA) | LED String Volt. (V) | Oper. Freq. (kHz) | Package/Pins | Budgetary Price |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
max | max | min | max | max | max | See Notes | |||||||||||
MAX1848 | 1-Cell Li+ | Inductor Based | 6 | 1 | Series | 0.06 | 20 | Analog | 75 | 0.8 | 2.6 | 5.5 | 2 | 12 | 1200 |
| $1.32 @1k |
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°C | RoHS/无铅:否 | |
MAX1848ETA+ | 生产中 | TDFN-EP,;8引脚;9.6mm² | -40°C至+85°C | RoHS/无铅:无铅 | |
MAX1848ETA+T | 生产中 | TDFN-EP,;8引脚;9.6mm² | -40°C至+85°C | RoHS/无铅:无铅 | |
MAX1848ETA-T | 停止供货 | MAX1848ETA+T | TDFN-EP,;8引脚;9.6mm² | -40°C至+85°C | RoHS/无铅:否 |