How do LED Drivers Work

What is an LED driver

LED lighting has proven to be more effective compared to incandescent or fluorescent lights, due to their high efficiency and long lifespan. Even though they are becoming more popular and are suitable for many applications, from households to horticultural lighting, many people are still unaware of how do they work. Just like any other technological innovation, they need something to drive them, and that’s an LED driver.

LED driver is a device that provides power to light bulbs. Since LEDs need DC current to operate, and the current flowing in households as well as in power lines is AC, the driver converts the current to DC and provides it to the bulbs. However, LED drivers are not solely providers of the current, they also act as the protection to the bulb itself.

How do LED drivers work

There are three types of drivers: constant current, constant voltage, and constant current/constant voltage drivers. They are meant for different situations. It is important to make sure they’re used properly since they do not provide the same thing.

Constant current drivers are applied for LEDs that need constant current and different amount of voltage within a fixture. This is not a common situation in LEDs since most of them require 12V to operate. Constant current drivers are used when the lamps don’t have the current resistor already installed. The type of LEDs that require current driver are supposed to be supplied by a specified current usually displayed in milliamps (mA) or amps (A). Higher current makes the LED brighter but in case it’s not regulated, it can consume more current which further leads to excess current that shortens the life of an LED. By applying the constant current driver, LEDs are supplied by constant current and maintain brightness and efficiency.

Constant voltage drivers are used when a light assembly needs stable voltage since the current is usually already managed inside the lamp or an assembly. These LEDs require one stable voltage and maximum output power, so the driver provides either 12V DC or 24V DC. This is usually specified on the light itself. The type of power which is typically found in our homes is 120-277VAC. Constant voltage drivers switch the alternating current voltage to low direct current voltage and maintain it for proper operation of the LED.

Constant current/constant voltage drivers feature both options, just like their name suggests. They run as constant voltage but they switch to constant current in case when output current passes the rated limit. Constant current/constant voltage drivers are used in applications where flexibility is required.

Does your LED driver need water/dust protection?

If an LED driver is installed in a place where it may come in contact with water or dust, it needs to be properly protected. Just like any electrical enclosure, it can come with a rated IP protection (Ingress Protection – used to define levels of sealing effectiveness against intrusion from foreign bodies and moisture). IP number usually consists of 2 digits, first one represents solid objects and second one represents liquids. So, if you are looking for a driver that can come in contact with water and dust, you can use an IP65 driver.

Here’s a list of definitions:

Solid Liquid
0 No protection No protection
1 Protection against solid objects >50mm Protection against water droplets
2 Protection against solid objects >12.5mm Protection against water droplets at a 15° angle
3 Protection against solid objects >2.5mm Protection against water spray at 60° angle
4 Protection against solid objects >1mm Protection against water spray at any angle
5 Dust protected Protection against water jets from any angle
6 Dust tight Protection against powerful jets
7 Protection against temporary submersion up to 1m
8 Protection against submersion in water over 1m

Life expectancy of an LED driver

All drivers have MTBF, or mean time before failure, and in order to maximize their lifespan and decrease maintenance costs, it’s best to run the LED driver at recommended outputs.

What lies ahead for LED drivers

LED lights and drivers are one of the most developing technologies today. US Department of Energy estimates that LED efficiency will reach 258 lumens per watt by 2020, or, 2.5 times more than standard fluorescent lamps. This will result in about 90% power savings. By then, the prices will drop thus making LED lights available to more households. One of the key points in the technology in the rise are LED drivers but many are unaware of their importance. Other than driving power to the bulbs, they are essential in providing a vast range of lightning designs. Each lighting solution needs a driver design, and the drivers themselves provide saving, ambience and definition to lighting installations. And last, drivers are the one responsible for efficiency and durability of LEDs.