An LED driver is the essential power supply for modern, energy-efficient LED lighting. It converts your building's high-voltage AC power into the low-voltage DC power that LEDs need to operate. It regulates the power, protecting the sensitive LED chips from fluctuations that could cause them to flicker or fail prematurely.

A light ballast is the traditional power supply for fluorescent and HID (High-Intensity Discharge) lamps. If you have older tube lighting, you have a ballast. It provides a burst of high voltage to get the lamp started and then controls the electrical current to keep it running steadily.

To ensure safety and longevity, it's best to follow the "80% Rule." Add up the total wattage of all the lights you will connect to the driver, then choose a driver with a maximum wattage rating that is at least 20% higher. For example, if your lights total 80 watts, you should select an LED driver rated for 100 watts or more.

The key difference is what they keep stable. A constant current driver maintains a fixed output current (e.g., 700mA) while letting the voltage change. A constant voltage driver maintains a fixed output voltage (e.g., 12V or 24V) while the current varies. Use constant current for high-power LEDs and constant voltage for fixtures like LED strip lights.

Common signs of a failing light ballast include your lights flickering, making an audible humming or buzzing sound, taking a long time to turn on, or not turning on at all. If you've already tried replacing the bulbs and the problem persists, the ballast is the most likely cause.