LED strip light

What do the numbers mean (5050, 3528, 3014, etc.)? These number correlate to the size of the SMD LED chip sizes in millimeters.^[1]

An LED Strip Light (also known as an LED tape or ribbon light) is a flexible circuit board populated by surface mounted light-emitting diodes (SMD LEDs) that usually comes with an adhesive backing. Traditionally, strip lights had been used solely in accent lighting, backlighting, task lighting, and decorative lighting applications. Recent developments in increased luminous efficacy and longer lifespans have allowed LED strip lights to be used in applications such as high brightness task lighting, fluorescent and halogen lighting fixture replacements, indirect lighting applications, Ultra Violet inspection during manufacturing processes, set and costume design, and even growing plants.^[2]

Design

Variables in strip lighting consist of colour, adhesives, and water resistance. Common chip placement within the tape allows light to emit away from the surface to which the tape is adhered (unless 'side view' or 'edge emitting', see below). Water resistant strip lighting is covered in a heat conducting epoxy to protect the circuitry from direct contact with water. The most common design differences are in how individual LEDs are controlled, specifically differences in color and whether or not each LED is addressable.^[3]

• Single Color, non-addressable: Every LED on the strand is a single white colour, typically ranging from 2700K to 6500K in colour temperature,^[4] or any of several monochrome colors covering the range of the visible spectrum (generally from 400-700 nanometers in wavelength).^[5] A single chip address all of the LEDs in the strand at once so each setting is applied to every LED
• Multicolor, non addressable: LED's of different alternating fixed colors, usually red, green, blue and amber, on a single address.
• RGB, non-addressable: Similar to the single color, non-addressable LED strand, RGB strands have multiple colours available but the entire strand uses the same address so all LEDs show the same colour.
• RGB, Addressable: Multiple colours and addresses. Each LED has its own chip meaning they can be individually triggered for chasing, strobing, and colour changing.^[6]
• 'Side View' or 'Edge Emitter': chip placement is such that light is emitted paralell to the adhering surface (ie, 90deg difference to typical tape design). Allows light to wash surfaces within less space or accent edge profiles such as signage.

LED strip lights typically operate on 12 or 24 volts of direct current from a transformer (driver). USB strip lights operate on the standard 5-volt direct current used by USB devices.^[7] Any customizations require an LED controller to adjust brightness, colour, or individual LED activity. This can be done with an included controller or customized with a microcontroller.^[3] Mains voltage LED strips are also available. These have the advantages of being usable in much longer single runs without a brightness drop along the length, but are less flexible and heavier due to higher voltage and current ratings and thick coatings for shock safety and high IP ratings in their intended outdoor positions, with limited cut points. No separate power supply is needed, although there must be a rectifier between the mains supply and the end of the LED strip.^[8][9]

Applications

Strip lights are designed for both indoor and outdoor use depending on whether they’re water resistant. Since the strip is flexible and can be divided at any point between LEDs, it is extremely versatile and can be used in a number of installations. Outside of traditional lighting, strip lighting is extensively used in DIY projects or lighted clothing. The ability to power strip lights off of a USB device or battery pack makes them extremely portable. Examples include: Computer lighting, costume lights, toys, workspace lighting, monitor and display ambient lighting, and alcove lighting.^[10]

References