Light Control Education


Fixtures & Bulbs

LEDs for general illumination are available in two basic types: fixtures and bulbs. Each is suited for a specific application, and has different criteria for design and performance. Knowledge of both fixtures and bulbs is essential when selecting the proper LED for your application.

A wide variety LED fixtures exist, ranging from traditional to unique LED specific designs. An LED fixture has either an integral driver or a separate driver (similar to a ballast); in both cases it is the driver that determines the dimming performance of the fixture. Fixtures with a separate driver have more flexibility to select a driver with the appropriate control type and performance.

Separate drivers are available in two types: constant current and constant voltage. A constant current driver provides a constant current, such as 700mA, to a pre-made LED array that is designed to operate at that current level. A constant voltage driver provides a constant voltage to several LED arrays connected in parallel, such as with cover lights. These types of drivers are not interchangeable and it is the design of the LED array that determines which driver is appropriate.

Lutron currently tests LED fixtures from other manufacturers to determine their dimming performance, either with a Lutron LED driver or a driver by others.

If you are interested in using the EcoSystem LED driver, please contact your local Lutron office.


As a whole, dimming performance of LED bulbs is improving as the demand increases. However, compatibility is still a confusing subject and customers that find good dimming performance from one lamp may be disappointed by the next.

Keep in mind these bulbs have a built-in driver and cannot use a separate driver to improve their dimming performance; Dimming performance in this case is determined by the circuitry within the bulb, just like a screw-in CFL.

Related Resources Making Sense of LEDs FAQs

Related Products EcoSystem LED driver