Looking for input on my upcoming project

Projects General Guidance
1

Hi everyone,

I have been a Arduino tinkerer for a bit now. Most of knowlege came off of the net. Went through all the basic stuff and then started putting bits and pieces together to see if it will work. My upcoming project involves schematic which I have done for first time ever. Please don't laugh to loudly as it is my first attempt. I would love to get some input on the design, parts, usage, and of course proper schematic design. All comments are welcome and greatly appreciated. I've included a pdf of the schematic.

Reloader.pdf (46.9 KB)

2

I see mostly minor problems, except that the IRF630 transistors may not work at all. You need logic level MOSFETs and certainly, lower valued gate resistors (e.g. 220 Ohm).

  1. No current limiting resistor on the speaker. 220 Ohm minimum.
  2. I would increase the pulldown resistors on the switches, unless they will be on long leads and subject to electrical interference.
  3. The starting current drawn by the motors might drop the voltage enough to reset the Arduino, or brown it out. I would increase the input capacitance on the regulator to at least 1000 uF.
  4. Don't forget decoupling caps (100 nF) close to the micro.
  5. It is not a good idea to connect AREF to Vcc, if you will ever use another reference voltage, and properly decoupling between Vcc and AVcc is a good idea. See the ATmega data sheet for suggestions, or this reference design.
  6. The LEDs are drawn the wrong way around.
3

@jremington,

I had 630 laying around and was able to use them in this way on the breadboard. Run them with the sketch that turn them on and off every 5 second for about an 3 hours, seemed it worked ok, but I definitely will look into logic mosfets.

  1. Added!

  2. The switches will climb my loading press to different locations, about 1 foot away each.

  3. 1000 mikes, done!

  4. Will have to hit the books to find out what are "decoupling caps" and how to implement them. I think I got it.

  5. Will read all of you suggested reference.

  6. Corrected (inserting here a big palm smack to the face)!

@godivaPrima
This was my interpretation of what I've done based on arduino kits. It worked a treat on the breadboard in this configuration. As far as LED symbols go see #6 above.

4

godivaPrima:
You may be wiring it right but drawing it wrong;

You are absolutely right! I did wire it just like the picture and then drew it wrong. Thank you! And I think only I look silly on this tread (munching on a humble pie).

5

Opps, my bad, I will attach new design in new posts from now on. Makes total sense to see where you came originally from with it.