Constant Current Power Supply Kit (up to 250mA)
This is the Constant Current Power Supply Kit. This kit is designed to supply a constant DC current to your load. It uses the LM317T in a constant-current configuration. The current regulation is typically 0.01% per Volt. It will deliver a very steady current, even under varying loads.
Constant Current Power Supplies maintain a constant CURRENT to the output load by varying the output voltage. As your load varies in resistance, such as when a load heats up or cools down, the output voltage varies just enough to keep the current across your load steady.
The Load Resistance be anywhere from 1 Ohm to 190 Ohms with a 12vdc input and the output current will remain a steady 100mA. Different input voltages will affect what Load Resistance are permissable. A lower input DC voltage may be used as long as the input voltage is 2.5v higher than the output voltage. The minimum input voltage allowed is 4.0vdc.
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. 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.