Controllerled

Controllerled is a general electronics term describing an LED whose behavior is controlled by a controller, such as a microcontroller, a dedicated LED driver, or a display controller. The term emphasizes that the LED is used as a status indicator, feedback element, or display component within a system rather than being driven statically from a power rail.

Operation typically involves a controller output that modulates the LED current or color. Common approaches include turning the LED on or off, using pulse-width modulation (PWM) to adjust brightness, and, for multi-color LEDs, selecting different channels for red, green, and blue. To prevent damage, the LED current is regulated by a resistor or, in common practice, by a constant-current LED driver or transistor/MOSFET switch.

Variants include indicator LEDs on PCBs, backlighting in displays, and arrays of LEDs used in numeric or bar indicators. Some LEDs include an internal driver and are addressed by a controller (addressable LEDs). In other cases, a separate LED driver IC supplies a constant current to multiple LEDs under the control of a host microcontroller.

Applications span consumer electronics, automotive dashboards, industrial equipment, and wearable devices. In all cases, the controllerled arrangement provides dynamic signaling or visual feedback synchronized with system activity.

See also: LED indicator, PWM, LED driver, addressable LED.