Any chance for a board to be produced?

[mred]

Jeroen, I'm interested. I'm happy to etch my own board, just don't feel capable of designing it. Maybe I can design it and get someone to check it?

[jeroen94704]

Ok, there's a few small modifications I need to make, but then I'll post the sch and brd files here, if that works for you. Since it's my first experience designing with Eagle, I'd be obliged if you could check my work .

[jeroen94704]

Here's what I have so far. A few notes:

- I reordered the pins used by the LCD display. This led to an easier PCB design, since in the original pin assignment there were a lot of connections crossing. THIS REQUIRES A CHANGE IN LCD.h though. You need to reverse the order of the LCD_DATA0 to LCD_DATA3 pins, so they go from 3 to 0, instead of from 0 to 3.
- There's a pin header called "SW1", which I use to connect 6 push buttons to control the player, instead of the tuner pot (for which there's also a pinhead). Feel free to leave it out.
- The circuit includes a power regulator circuit, which accepts anything between (I believe) 7 and 15 volts, and outputs 5 volts.
- The PCB was generated by Eagle's autorouter. It looks fine to me, but I haven't made/tested this design yet.
- There's a pinheader for the ISP programmer, but it's of the 6-pin variant., while I believe the 10-pin variant is more common. I could replace this with a 6-pin female pipn header which accepts the sparkfun ISP programmer breakout board, if it's an issue.
- There is a single remaining air-wire that needs to be connected manually. This would be trivial to fix using a second layer, but I really wanted to stick to a single layer PCB design.

Again, this is my fist attempt at making a PCB using Eagle, and it has not been produced/tested yet. Please let me know what you think or any problems you may find.

Jeroen

[mred]

Hi Jeroen, it looks good to me, but I am certainly no expert. There are a couple of lines crossing in strange ways near IC2, not sure quite what is happening there....

[jeroen94704]

Yeah, that's the autorouter being silly. Those traces are all connected to ground, but the autorouter only does 0-45-90 degree paths, and it doesn't fill polygons or anything.

I realized I used the "top" layer for the routing though, which is probably not what you want if you send in this design to a PCB supplier. I'm changing that to the "bottom" layer.

Jeroen

[jeroen94704]

Here's a new version of the board. The autorouter pissed me off, so I did the routing manually this time. This has lead to a much tighter design, IMO. I also removed the voltage regulator circuit, since the power supply solution will probably differ for every build, and it didn't make sense for the solution I'm thinking of for my build anyway. There's a 2x1 pinhead where you can supply your own 5V regulated. The board passes the default Eagle DRC with no errors or warnings. No guarantee, I know, but encouraging nonetheless.

Again, just looking for feedback here, since the board has not been made/tested yet. If nobody points out any obvious problems I'll go ahead and create it to see if it works at all .

Jeroen

[jeroen94704]

Ok, one more revision. I got the advice to avoid 90 degree angles in PCB's, so here's a design without them. I also added back a 10 uF stabilizing cap near the 5V input, just to be safe.

Jeroen

[mred]

I can't see any issues at this stage Jeroen, so please let me know how it goes. It does look way better than the autorouted version Well done!

[jeroen94704]

It works!

This is the board after etching (The picture is blurry, not the PCB ). As an aside, this was my absolute first ever try at toner transfer PCB production, and I'm amazed at how easy it is and how high the quality of the result is. I'll definitely be making many more PCB's using this method.



And here it is after drilling and soldering the components:



Finally, this is what it looks like in action, along with the display, a small keypad I whipped up, and a voltage regulator circuit:



So go ahead and try it yourself. With a pot meter connected instead of the keypad, this should work with Jeff's firmware (with the caveat that you have to make the change in pin assignment I described earlier). I have NOT tested this though.

Jeroen

[gerben]

I don't know anything about circuit building and pcb, but the results looks very good. Nice job!