Smallest Arduino? Smallest battery? USB?

Projects General Guidance
41

Robin2:
Answer is in Reply #31 - flux.

...R

Excuse my ignorance here. A state of flux is the only flux I have heard of before. Is this 'flux' the process of using a heated solution to dip the shielded wire in to remove the coating or is it something else? I see some tutorials online for using a chemical solution to remove the shielding.

CrossRoads:
Those are size 1206 LEDs next to 0805 resistors.
Comparet to the 0805 LED and 0805 resistor at the upper right of this board
If you use 1/8W resistors, those bodies are pretty small, but still gives leads to work with.

Thanks for this information. I'll add 1/8W resistors to the shopping list so.

42

Solder flux, for clearing the oxides off your iron.
I use a gel form.

43

GoForSmoke:
Solder flux, for clearing the oxides off your iron.
I use a gel form.

Ah ok, great. A simple and tidy solution. Something like this would work presumably so.

44

I'm not so sure either way.

45

CrossRoads:

931×914 335 KB

Isn't that the

1284Mini.

ATMega1284P-AU with 32 IO, Dual Hardware UART, 128K FLASH, 16K SRAM. Schematic, Layout, PL
Bare Boards $3. Kits, $15. Assembled boards with straight male headers $20. Add USPS shipping & paypal fee.

That looks good!

46

minibuilder:
Ah ok, great. A simple and tidy solution.

I have a small (50g) tin of Fluxite. It is probably 20 years old. I have not yet used all of the stuff that is stuck to the lid - the contents of the tin proper is almost untouched :slight_smile:

...R

47

vinceherman:
Do you have a charger that can treat those batteries gently during the charge cycle?
I have a lot of very small LiPos, and my experience shows that the smaller the battery, the easier it is to damage them with fast charge times. Definitely under 1C for longest usable lifetime.
The specs for this battery list 100mA charging current, but if they were mine, I would go with 50mA.

Although at under $5 each, I might be less worried. Mine were $15 each.

I was going to use some TP4056 module from ebay (one with a protection circuit since mine didn't come with one) and replace the default resistor with something like 20k. This will bring the charging current down from 1000 mA to 65 mA.