Constant Voltage Drivers vs. Constant Current Drivers and TRIAC Drivers

LED lighting runs on low voltage, direct current electricity, but electrical outlets normally supply high-voltage electricity with alternating currents. LED drivers help turn the high voltage, alternating current electricity into a low voltage and direct current electricity necessary for LED lighting. While there are different kinds of LED drivers, Constant Current and Constant Voltage drivers are great options for power supply when it comes to LED lighting. Differing in how they deliver the power to LEDs, they both regulate the necessary power to maintain effective LED lighting.

Constant Current LED Driver

A constant current LED driver changes the voltage across the circuit to maintain a constant electrical current and guarantee that the current is maintained. Constant Current LED drivers are designed for LEDs that are rated to operate on a constant current driver which require a designated supply of current constantly driving through them. While higher current ratings make the LEDs brighter, these currents must be regulated to prevent damage to the LEDs. By maintaining a consistent current, you’ll get consistent brightness across the LEDs and avoid violating the maximum current specified for the lights to help avoid burnout. They also are easier to use for lighting designers of all levels to control applications and create a consistent brightness throughout the project. Constant current drivers are used for illumination as they allow for more uniform control of the light quality.

Constant Voltage Drivers

These drivers are designed for a single direct current output voltage and for LEDs that are rated for constant voltage. The driver receives a standard line voltage typically output from the wall outlets around your house. Constant Voltage drivers switch the alternating current voltage to a low direct current voltage to maintain a constant voltage no matter the current load. These drivers are used for LEDs who need a stable voltage and have a current that’s already regulated. Most commonly used for under-cabinet lighting and LED flex strip applications, constant voltage drivers are a more familiar technology for designers and installers. Great for businesses, constant voltage drivers are ideal for signage and other applications that rely on vibrant, contrasting colors. They’re also more cost effective than constant current drivers and easier to work with.

Triac Drivers

TRIAC Drivers provide flexibility for lighting designers when used with a TRIAC to create discrete, high powered lighting. Composed of an input LED with a photo-sensitive TRIAC driver chip, the LED shines light on the chip to allow a current to flow through the device and then through the gate of a discrete output, allowing the load to be switched on or off. Typically used in dimming applications, TRIAC dimmers are the most common dimming control for LEDs. These dimmers control the amount of electrical energy passing through a lighting fixture and prevent the voltage from being fully supplied. TRIAC dimmers are designed for resistive loads, which some LED solutions are not, so it’s important to find the right TRIAC driver to keep your LEDs performing optimally.