低功耗的PWM输出控制LED亮度

摘要：一个普通的LED的亮度控制电路采用电控电位器（EPOT）实现数字控制LED亮度。然而，更换一个RC网络的EPOT减少IC的数量和所需数量的控制线。

Maxim>AppNotes>DisplayDriversKeywords:PWM,pulse-widthmodulation,LEDbrightnesscontrol,LEDcurrentregulator,LEDdriverJul19,2006APPLICATIONNOTE3866Low-PowerPWMOutputControlsLEDBrightnessAbstract:Acommonbrightness-controlcircuitforLEDsusesanelectricallycontrolledpotentiometer(EPOT)toachievedigitalcontroloftheLEDbrightness.ReplacingtheEPOTwithanRCnetwork,however,reducesboththeICcountandtherequirednumberofcontrollines.AsysteminwhichamicrocontrollerorprogrammablelogiccontrolsoneormoreLEDsoftenrequiresthecapabilityofcontrollingLEDbrightness.Acommonapproachforachievingthisadjustsanelectricallycontrolledpotentiometer(EPOT),whichinturn,controlstheLEDdr