I’ve been working on a new project recently. Actually, “recently” isn’t necessarily the best word. I’ve been poking at it for months, but only really putting in an hour or two a week here and there, so it’s been coming along very slowly. At any rate, the project idea is very simple: I’m just making an RGB LED lighting rig for my fish tank (and perhaps for general accent lighting elsewhere around the apartment). The system will have a character LCD and some pushbuttons so that a user can create “programs” to schedule different RGB gradient stops throughout the day. Also included is an IR sensor so that the lighting setting can be changed via universal remote control.
However, what this post is really about is the PCB for this project (whose Eagle layout is shown above). I decided that it would be cool to forgo the homemade PCB process (via toner transfer and acid etching) and utilize a true PCB prototyping service for the first time. The decision was made when my friend, Jon, discovered iTeadStudio. Based in China, one of their product offerings is low cost PCB prototyping services. When I say low cost, I mean as low as $10 for 10 boards (+$4 shipping to the U.S.)! This is incredibly cheap, as domestic PCB services can easily cost five to ten times as much.
At any rate, I just got my boards in earlier this week and wanted to share some feedback about iTeadStudio and my PCB design in particular. The pictures below show the manufactured PCBs.
Overall, I am very happy with the results. For the most part, the boards look great. However, there were a couple of very minor issues. Notice, for example, that in the picture of the top side of the board, there is a light scratch across the board. This is not problematic, as it is a minor surface scratch that does not permeate through the solder mask layer. It nevertheless a slight aesthetic annoyance. Another slight aesthetic annoyance is that iTeadStudio (or, more likely, their manufacturer) has printed a serial number, or some such identification information, on the top silkscreen layer. Again, this isn’t really problematic, but it was a little bit unexpected, and I’m very curious to know how they choose the placement for that text.
A more serious issue is highlighted in the last photo. Notice that, in the upper-right corner, there is actually a defect in the copper layer beneath the solder mask, and that some of the copper is missing. Fortunately, in this specific case, the cutout does not completely cut through the trace. However, if the defect were located elsewhere or I were using thinner traces, this could have easily resulted in a non-functional board.
Despite these issues, though, I am actually very satisfied with iTeadStudio. The picture above that shows a defect is only representative of one of the ten boards. The other nine appear to be flawless under visual inspection. I actually received an 11th board in my order (not shown) that did not have the marker on the edge, as depicted in the first photo. I don’t know whether there is any significance to this, or why I received an extra board, but I figured that it’s worth noting.
Another nice part about iTeadStudio is that they actually appear to have fixed a critical error that I made while generating the Gerber files. In Eagle, when running the CAM processor, apparently you should always check the “pos. Coord” setting when exporting your drill layer in order to make sure that you don’t have negative coordinates in your drill layer due to a coordinate system whose origin might be outside of the dimensions of your board. I did not take this step. I believe that the following rendering (generated from the Gerber files that I sent to iTead using Mayhew Labs’ webGerber) is the way that my board would have turned out, had they not corrected it. Obviously, the drill holes are offset from their intended positions and would have been disastrous if manufactured in this manner. Fortunately, the PCB manufacturer must have caught this and made the appropriate correction (although it would have been nice if they at least notified me of such).
Overall, I would say that, despite some potential problems with iTeadStudio, for the money it can’t be beat. Even if you do end up with a board that has a defect, you’ll probably end up with 9 others that are fine, which is still a bargain. Also, because they claim 100% e-testing on the boards, it should also (presumably) be very evident which, if any, of the boards are defective.
Lastly, I did want to link to a few popular stories revolving around iTeadStudio’s PCB service. Again, even though I was happy with my boards, there are some tales of iTeadStudio (or their manufacturing service) adversely modifying Gerber files or failing to conduct the claimed e-testing on the boards. If you’re considering iTeadStudio, it may be worth taking a glance at these links first as something of a disclaimer:
http://dangerousprototypes.com/forum/viewtopic.php?f=2&t=3468&sid=c54693852480bf48e601e0f9093875bf
http://hackaday.com/2012/05/10/are-your-pcbs-being-tested-as-claimed/