The short answer is no. However, when everything is done and shipped, I may have a few extras, at which point I will post how many and offer them on a first come, first served bases. Payment will happen through PayPal.
Real world test with different inductors. There are always slight trade off's when you choose one part over another (whether it's cost, size, performance, safety, anything). In the case of this charger, keeping cost the same, I have been testing the trade off of slightly more output ripple for better temperature handling at higher charge currents.
Below are pictures of two functionally identical chargers, charging pretty closely matched batteries at 500mA (1Amp pulsed between the two) but with different inductors. Using an infrared thermometer I carefully found the hottest point on each inductor.
As you can see the 100uH inductor which is physically the same size as the other 270uH inductor, but has fatter gauge wire inside, runs almost 11 degrees cooler.
A big thank you to Everyone for all the support on Kickstarter. I want to take a moment and give a special thanks to:
Fantastic Mista Fox
These are they who gave $5 each to the cause without anything in return. Thank you again!
It isn't too often you get to order 10,000 of something. It is still a week and a half before I get the money from kickstarter but I decided to take a risk and start ordering some of the parts now. It was a new experience ordering so many parts with my OWN credit card. Over 4,000 0.1uF caps, 10,000 1K resistors and many other components in large quantities.
A few renderings of the charger with optional LCD attached and the optional acrylic case. I made the charger 3mm wider on each side as well as a little longer to accommodate the mounting holes for the case and to give me a little extra room for some of the additional features I have added.
Although the color is not final yet, the individual who pledged $150 on Kickstarter (and therefore gets to choose), had wondered what it might look like in white.
I was having trouble with the durability of the spring loaded eject mechanism on the SD slot. If not careful it would wear out rather quickly and eventually the SD card would either get stuck in, or out (meaning you couldn't get it to stay in).
After looking at my USB card reader, which doesn't give me any problems, I decided the answer was to ditch any sort of spring loaded anything! I couldn't have something I made go out only to have people upset because it broke after a few weeks/months.
I looked at a few different places and bought a couple different SD slots so that I could test them out and see what I liked best. These are my two favorites (I kind of like the shorter one best).
I will put a rounded cutout in the PCB above the top part of the SD card so that you can just grab the end with your fingers and pull it out (or push it in) without having to worry about some spring eject thingy breaking!