This is a continuation of this question.

enter image description here enter image description here

Note that some of the circles should be filled, but have connections instead.

PCB Color Legend:

  • Red: Top Copper

  • Blue: Bottom Copper

  • Purple: Inner Copper 1

Extra note: There will be a ground plane on top copper.

Component Reference:

MC1: AC32UC3
REG1: LD1117 (3.3V 800mA)

White ovals are crystals with 21pF ceramic caps

I have uploaded the schematic, viewable on the software maker's website here.

Recap Qs:

  • The manufacturer says a maximum of 1oz. Does this mean that I should make the ground plate smaller to compensate for that weight limit, or will I not hit the limit (board is 3"x5") ?

  • The GPS says no wires should go under the chip, will the ground plane be okay going under the GPS?

  • Does this design look alright to the eye?

  • \$\begingroup\$ For starters.Your GPS chip seems to be missing two pins (to GND) 21 & 22. Trace width might be to narrow, if you are using a lot of current for your motors (no link). Schematics might help others. You have some funny traces near the Li-Po connections. \$\endgroup\$ – Tyler Oct 7 '15 at 22:31
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    \$\begingroup\$ It would help if you posted a schematic. It looks like you're missing components you should have (e.g. bypass caps). It's much easier to review that kind of stuff in a schematic than in layout. \$\endgroup\$ – Doov Oct 7 '15 at 22:42
  • \$\begingroup\$ I don't see any thermal relief for your components that get soldered to ground. You'll have a harder time soldering those components. \$\endgroup\$ – efox29 Oct 7 '15 at 23:24
  • \$\begingroup\$ Forgive my ignorance, @michaelyoyo. If i'm not selling this, what does making pretty do for me? i can understand the 90 degree bend issue, the narrow trace issue, and even the text issue. but why make it 'pretty'? \$\endgroup\$ – user86234 Oct 7 '15 at 23:25
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    \$\begingroup\$ SHOW A SCHEMATIC! \$\endgroup\$ – Olin Lathrop Oct 7 '15 at 23:27

Briefly, 1oz is usually referring to the copper weight and is a specification of weight per unit area. Or in other words the thickness of the copper. Standard weights are 0.5oz for fine pitch, 1oz standard, or 2oz for high current. It is not changed by the size of your board or the ground plane.

Your layout has lots sharp edges and traces are much longer than they need to be. Definitely remove any angles less than 90. Eg under the crystal. Preferably remove 90 degree trace corners.

A schematic would be useful to know what's going on in the circuit.

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1) You still don't have a ground plane. Your chances of this working without one are somewhere be small and zero.

2) You still don't have the decoupling caps the MCU needs. The MCU is going to go crazy.

3) You have not addressed the question of exactly how you're going to install the accelerometer.

4) You still don't have a ground plane.

And no, 4 was not a mistake on my part.

Stop trying to do this with two layers!

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    \$\begingroup\$ Further, why oh why are you mixing surface mount and through hole? \$\endgroup\$ – Matt Young Oct 7 '15 at 22:32
  • \$\begingroup\$ I didn't add a ground plane because that would make the bottom layer invisible. just for clarity: a ground plane is on the same layer as the top, right? or is the ground layer generally dedicated? \$\endgroup\$ – user86234 Oct 7 '15 at 22:35
  • \$\begingroup\$ also, I've circled the decoupling capacitors in this image: imgur.com/8z9rdPg the component I1 is an inductor between the Vsupply and the Regulator input \$\endgroup\$ – user86234 Oct 7 '15 at 22:38
  • \$\begingroup\$ @tuskiomi can be on the bottom as well, just make sure that there are as little breaks in there as possible (best would be no traces at all). \$\endgroup\$ – Arsenal Oct 7 '15 at 22:39
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    \$\begingroup\$ A 4 layer board typically wont have real interplane capacitance. As @michaelyoyo said, if you have sufficient decoupling caps you are good to go. You can make one of the planes vcc or make both ground, and route power seperately on the top or bottom layer through a ground pour or thick traces. Either would work. \$\endgroup\$ – efox29 Oct 7 '15 at 23:20