24 Channel USB Connected LED Controller, upto 1A per Channel

Step 5 Electrolytic Caps, USB-Type B Jack and Optional 7805

Capacitors:

- Both the electrolytic capacitors are 1uF and are polarized.

- The black stripe is indicates the negative lead, also the black line in the capacitor on the top-side illustration.

- Place both capacitors, C3 & C2.

USB Jack:

It only fits in one way, install it and solder in securly.

Optional 7805:

7805 are linear regulators, meaning they dissipate energy as heat when bringing down the voltage. 

Based on input voltage and transistor sinking/sourcing a 7805 may or may not be used.

If you are going to use an input voltage greater than 5v for the LEDs, the circuit board will either need a separate 5v supply(recommended) or the 7805 can be installed, but note even with no LEDs connected the circuit draws upwards of 300ma of current. Depending on the input voltage the 7805 may have to dissipate a lot of heat and may need a heatsink.

I tested a 1A 7805 and a 12v input and the 7805 became to hot to touch after a few minutes. And couldn't be used.

If the circuit is using a 5v input(recommended) the holes for the 7805 need to be jumped and soldered.

- Using a heavy piece of solid wire, jump holes 1 and 3 in VREG.

- On the copper side fill in the solder pad for hole 2 with solder. 
*The images below show the 7805 not installed, and the proper jumps made.