Constant-Current LED Power Supply Kit (up to 250mA)

Constant Current Power Supply Kit (50mA)
Constant Current Power Supply Kit (50mA)
Price: $7.99

This is the Constant-Current LED Power Supply Kit. This kit is designed to supply a constant DC current to your LEDs. This will maintain a steady current flow to your LEDs. It can be used to check the brightness of your LEDs by giving them a constant current.

This may be used for LEDs in series or in parallel. The input voltage for a single LED may be as low as 5vdc and can go up to 25v. The minimum input voltage required to properly deliver the fixed amount of current is equal to the LED voltage drops plus 2.5v. This means that if you have 3 LEDs in series that require 2.2 volts each, then the required minimum input dc voltage to the constant-current power supply is (2.2 x 3) + 2.5v = 9.1v. In this example, a 9v battery would work fine. You could also use a 12v power supply or even use your car battery power.

The input voltage can be anywhere from 4v to 25v. The higher voltage inputs may require a heatsink on the LM317T. A heatsink is not supplied with this kit.

Please select the Constant Current value you need. The default value is 10mA. Available currents are from 10mA to 250mA. If there are any other values you need, please contact us. These are fixed values that the power supply will deliver, they are not adjustable.

This kit is also offered as a Built & Tested for those that do not want to build the kit themselves.

The PCB is small and compact. It is 1.0" x 2.0" with 2-pin screw terminals for the input and the output. It also has 2 mounting holes. The PCB is 0.062" thick, double-sided, plated thru-holes with silkscreening on the top side. This is a low-profile kit and is about 1/2 inch in height when built. You get the PCB, all of the components, and a schematic. This is a kit which will require that it be assembled. You will need tools, such as, a soldering iron, solder, wire cutters, etc.