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Looking for Feedback on a PCB design

Former Member

HI folks! First off, I just wanted to say that I am completely new to this Forum and PCB CAD design in general, so forgive me if I am posting in the wrong place and please kindly point me in the right direction. That said, I've been playing around with Eagle for about a week and I have come up with my first design that I would like to get some feedback on.   The board consists of an ATTiny that controls a dual N-channel MOSFET ( http://www.digikey.com/product-detail/en/SI1970DH-T1-E3/SI1970DH-T1-E3CT-ND/1656832), and a dual NPN transistor (http://www.onsemi.com/pub_link/Collateral/BC846BDW1T1-D.PDF ) which in turn drives an H-Bridge (http://www.diodes.com/datasheets/DMHC3025LSD.pdf). Initially, I had wanted to try to etch my own board and assemble it myself but it appears far too intricate for my current soldering skills. Maybe if i had a reflow oven... I digress. Comments, suggestions please. Do you think if I sent this design to a company they would be able to make it? Any other relevant files I need to upload as well? Hmmm I can't seem to upload the eagle file. well lets try a JPG image..

Thank you for reading!

Sean

Attachments:
image

  • Hi Sean,

     

    For a company to be able to make this, you'd need to supply a few files (gerbers) and it's

    best to check the company website for the specifics of what they want (such as naming). They will also specify

    their capability (e.g. minimum track width). Your design is not using very tiny parts, so you're

    likely to be ok here.

    For a company to create the entire board, this will cost a lot (guessing $50 per ic) in a single

    board volume, which is expensive considering each ic could be hand-soldered in minutes. So, even factoring in

    your time, it may be cheaper to get just the PCB created, and for you to manually solder the parts. This

    is not hard with a soldering iron, no need for reflow. Check some of for soldering

    hints/tips.

     

    Regarding the actual board, it looks like you could save space if you wanted to. You may also want

    mounting holes (and washer/bolt head clearance) in your design, and connector(s). Also, although there are

    thicker traces in places, they are not a replacement for power planes which are possibly needed for your application.

    H-bridges or general high-current switching can be complex things. But your design may be fine for your

    proof of concept (but would probably require a board redesign for the final implementation).

     

    Have a look at this example which was the only one I had at hand. (it is not an optimum design - it

    was a quick test setup) but the area performing the switching of a load has power planes. This example was not designed

    for as high a current capability as your design. The planes are responsible for providing the current demanded

    under sharp switching conditions.

    image

     

    Some ICs have reference designs provided by the manufacturer, and a visual inspection of their PCB drawings

    can also provide valuable tips on how you design the PCB. It is the first thing to look for, when creating a

    PCB with a new device. If a reference design doesn't exist, then the device datasheet may have tips anyway, or the

    manufacturer may have a library of general application notes that could help.