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An RGB LED module is an assembly of one or more multi-chip LED packages on a printed circuit board, substrate, or mounting system. The assembly may come with optical elements, control circuits, and additional thermal, mechanical, and electrical interfaces. An RGBW LED module can be an assembly of one or more LED packages which integrate red, green, blue chips plus a white LED. It can also be assembled in a way that RGB LED packages and white LED packages are mounted neighboring each other to provide cross-package color mixing. Adding a white LED to an RGB LED results in better-quality whites, enables saturated reds and a full range of pastels, and extends the hue, saturation and brightness values available in the color system. Adding additional colors, such as amber, to an RGB or RGBW LED modules can expand the gamut. For example, the addition of an amber LED to an RGB LED expands the available range of colors to include warmer tones such as rich gold, yellow, and orange shades. RGBWA LED modules can produce deep yellows and oranges that RGBW LEDs cannot.

RGB/RGBW LED modules in various configurations have an extensive range of applications. They are designed for channel letters, signage lighting, under-cabinet lighting, media facades, low-density video displays, landscape layout, stage adornment, decorative and accent lighting. Creating the right color for these applications is a major challenge. Typical color accuracy requirements for additive color mixing applications are ± 0.01 in u’v’. To produce a full spectrum of precisely controllable light, each of the LED channels of an RGB/RGBW LED module must be accurately controlled in output.

Controlling the output of the component LEDs is typically made through pulse width modulation (PWM). LED drivers that support PWM dimming can provide a very precise output over the full range from 100% to 0% without color shift. An alternative to PWM dimming is continuous current reduction (CCR) which simply reduces the drive current for each LED. Changing the operating current linearly may not result in a linear change in light output. A color shift can occur when the current to the LED is below the rated current. As a result, dimming RGB LEDs with CCR is undesirable. The individual brightness of each LED can be controlled in PWM steps of 1/256 or higher, whereas CCR dimming allows only 10-to-1 dimming ratios. PWM dimming can be easily implemented using the integrated circuit (IC) chips. The IC that is built into the module receives data from the controller and adjust the output of each component LED.

Individually controllable RGB/RGBW LED modules are also referred to as LED pixels or LED nodes. Uniquely addressing and individually controlling enable output of different colors and different brightnesses on multiple nodes simultaneously. This level of control allows multiple lighting nodes to act in unison for displaying an infinite variety and combination of dynamic effects, delivering intricate light shows, generating graphic animations, and mapping video content.