For human-eye-friendly visual performance, a logarithmic-scale dimming curve is usually implemented in LED drivers. However, for RGB LEDs, if using a single register to achieve both color mixing and intensity control, color distortion can be observed easily when using a logarithmic scale. The LP50xx device, with independent color-mixing and intensity-control registers, implements the logarithmic scale dimming control inside the intensity control function, which solves the color distortion issue effectively. See Figure 8-2. Also, the LP50xx device allows users to configure the dimming scale either logarithmically or linearly through the global Log_Scale_EN register. If a special dimming curve is desired, using the linear scale with software correction is the most flexible approach. See Figure 8-3.

Figure 8-2 Logarithmic- or Linear-Scale Intensity Control

Figure 8-3 Logarithmic vs Linear Dimming Curve