Build UV Circuit

While your 3D printer is going, solder up the UV LED board! First place your perma-proto securely in a Panavise.

Arrange the LEDs evenly across the two sides of the boards, keeping each LED leg in a new row but distributing them laterally to fill the whole board. It's helpful (but not strictly necessary) to keep all the LEDs in the same orientation (all long legs towards one side). Here's an LED layout diagram:

Slightly bend the legs of the LEDs outward at the back of the board to help them stay in position, but tape can help too. Don't worry about the LEDs being perfectly flush to the board yet. Flip the board over and solder only one leg of each LED.

With the board upright or LEDs-up, reheat the soldered leg until molten, then press the LED flush to the board. Let the solder cool and harden for a moment before lettng go of the LED.

Now that your LEDs are flush, you can now solder the other half of the LED legs. If all your LEDs are in the same orientation, you can trim the legs short on all but one or two, which can help you remember which is which for the next step.

Solder a 100-ohm resistor connecting the ground bus to each LED's negative leg. Solder a solid-core wire connection between each LED's positive leg and the power bus. You can reverse this if you wish (resistor between positive and power, wire between negative and ground). Each UV LED has its own resistor and is wired in parallel to the power and ground buses. Here's what those connections look like without the LEDs cluttering up the diagram:

You can solder the resistors and wire to either side of the permaproto. The finished circuit looks a little neater with the resistors on the back, but the circuit is easier to troubleshoot with them on the front.

Use wires to connect one side of the permaproto to the other-- ground to ground and power to power.

Solder two long silicone wires to the corner of the circuit as shown (red for power and black for ground).

This guide was first published on Sep 02, 2014. It was last updated on Sep 02, 2014.
This page (Build UV Circuit) was last updated on Aug 07, 2020.