single sided A3977 board ( got files uploaded )

[tekno]

I have made a single sided A3977 board. I used Phil’s schematic to build the board so that his instructions will still work (thanks Phil for answering all my questions). It is kind of big at 100 mm X 140 mm but was build so the hobbyist board maker could etch their own boards. The output traces are to light for the 2.5 amp output but are made so that 18 to 20 ga. solid wire could be soldered on to the traces to carry the load. The board has 4 jumpers that are shown on the top copper mask. I have the top silk. top copper (you don’t really need) and Bottom copper. Plus the board lay out. I think its 100%.


Tek

[BobLWeiss]

What program did you use to do this? I was looking at the bottom copper and it looks like you have shorts on the middle leads of the chip. The lines are very coarse too, do you have a sharper version so that it could be used for toner transfer method?

Thanks,
Bob

[tekno]

Sorry, it looks like my adobe settings are not right. I used Circad98 to build the board. I have png file but their at home.. I’ll up load them tonight.. Im not sure if the lines are too close. I have the Circad file with me.. I changed that area in question a little and up loaded the pcb file

[tekno]

heres the file.. I had to zip it to get it to up load

[pminmo]

One comment,
I would suspect most people will have to use a 74HC14N instead of the 40106. The are pin for pin compatable, the 74HC has a lower threshold and should work for all PPorts, except some laptops.

Phil

[tekno]

Well I got my A3977SLP chips today and there alot smaller then the chip layout I used... so for now this board will not work.

sorry

[pminmo]

Little boogers aren't they. I've wondered how practicle they are to hand solder. Tekno, you might want to use the free version of eagle to recapture your board. You've solved the puzzle of how to get it reasonable on one side.

Phil

[BobLWeiss]

Yes, I didn't mean to sound like I was ungrateful or anything, I totally appreciate your work on getting it to one sided..that isn't easy with this chip. Good Job!!

I got those chips as samples too and when I first saw them I was like no way it can handle 3amps going through them...crazy isn't it? I use Eagle all the time and I would use that if you can, it does a great job of routing and easy to make new packages for those chips. If you want, I can make the parts for you in Eagle and you can then do your board in that. Glad to help!!

Bob

[Sanghera]

Hi all,
I was just wondering what the cost of a complete board would be, 1 axis or 3 axis. After all of the parts are purchases, ie. board, etching compound, etc. etc.
Thank you very much for the help.
I really appreciate it.

[BobLWeiss]

I would say your looking at $20 to $30 a board based on wether or not your purchasing the chips for one, making your own board at home and already have all the necessary supplies on hand for that, and you have a some parts already like resistors etc... Too many factors to put an exact price on it. For me, since I already etch boards, it would cost me $15 a board probably with purchasings caps and connectors etc...

Bob

[Sanghera]

Cool, thanks.

[pminmo]

Tekno,
Attached is an eagle schematic basically of my board but with the 28pin tssop. Also the unrouted board file. I did the tssop model and haven't double checked it so you might want to make sure I got it correct.

Phil