NXP PCA9685 I2C总线控制LED控制方案
NXP公司的PCA9685是16路 I2C总线控制LED控制器,非常适合LCD红/绿/蓝/琥珀(RGBA)彩色背光应用.每路LED输出有它自己的12位分辨率(4096级)固定频率单独的PWM控制器,可编频率从40Hz到1000Hz,占空比可从0%到100%间调整,以设定LED亮度.LED输出驱动器可编成漏极开路(5V是沉电流25mA)或图腾极(5V时沉电流25mA,源电流10mA),电源电压从2.3V到5.5V.本文介绍了PCA9685主要特性,方框图,开关时间测试电路以及典型应用电路和LCD背光应用电路.
PCA9685: 16-channel, 12-bit PWM Fm+ I2C-bus LED controller
The PCA9685 is an I2C-bus controlled 16-channel LED controller optimized for LCD Red/Green/Blue/Amber (RGBA) color backlighting applications. Each LED output has its own 12-bit resolution (4096 steps) fixed frequency individual PWM controller that operates at a programmable frequency from a typical of 40 Hz to 1000 Hz with a duty cycle that is adjustable from 0 % to 100 % to allow the LED to be set to a specific brightness value. All outputs are set to the same PWM frequency.
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