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The difference between constant current and constant voltage for powering LEDs
2020-05-06 23:44:22
 The difference between constant current and constant voltage for powering LEDs

LEDs for lighting are found anywhere from DIY IoT modules to commercial lighting applications and the cabins of airplanes. To run properly, these critical lighting devices require a precise balance of current and voltage to deliver the right amount of power. Many LEDs used in a home have built-in or external power supplies that convert wall outlet power to the appropriate power for efficient operation of the LEDs. It’s similar, though on a larger and more

complex scale, with industrial lighting. Hence, the efficiency, cost, and scalability of the power supply type is important to consider depending upon the application. These factors tie into the types of power supplies used to drive the LEDs.
Constant current LED drivers have a fixed current in amperes or milliamperes and a variable voltage. Constant voltage drivers are similar, but opposite,
with fixed voltages and variable currents.
A key differentiating factor between LED drivers is if they are constant-current or constant-voltage operation. This matters because many LED
technologies are designed to operate only with constant current or constant voltage. The use of a different style of driver can lead to poor operation and even LED failure. LEDs can be damaged by too high a current or too high a voltage, so it’s important to understand the operational parameters of the LEDs themselves before purchasing and installing an LED driver
How do you know if an LED device needs constant current or constant voltage?

Constant-voltage LED drivers will typically have a fixed voltage rating of 5 V, 12 V, 24 V, or some other voltage rating with a range of current or maximum current. Constant-current LED drivers will have similar ratings but be given as a fixed amp (A) or milliamp (mA) value with a range of voltages or
maximum voltage. The LED device should give an indication of what its power requirements are, along with nominal ranges for voltage and current. If it’s just an LED, then current control is necessary to prevent the LED from going into thermal runaway.

LEDs are diodes that consume power and convert it into light. This process, however, is not perfectly efficient and some internal losses exist, producing heat. As an LED gets hotter, it becomes less efficient and consumes more current. If an infinite current and infinite voltage power supplies were to drive an LED, the LED would continue to draw more current until it failed. Hence, constant-current LED drivers are used to ensure that the current of an LED never leads to thermal runaway.
Typical Constant current LED driver:
IP67 waterproof led power supply
Typical Constant Voltage LED driver:
3 years warranty