This is the final article in my ATtiny2313 breadboard header series. In the previous parts we’ve looked at:
- Designing the header with DipTrace, as well as creating custom components in DipTrace
- Creating a PCB layout with DipTrace from the schematic
- Checking PCB against Olimex manufacturing constraints and creating Gerber files
In this part, I’ll have a short review of the PCB ordering process with Olimex, and a bit how the boards turned out. Let’s get going!
Ordering PCBs from Olimex
Once I had the Olimex technical requirements studied forwards and backwards, and the tedious design rule check process completed, I was ready to submit my order to Olimex. It was only a matter of sending the zip file to Olimex to get a quote. They promise a quote in 1-3 working days, and surely enough, I submitted my query on thursday evening and got the response early next week.
I had asked to pay with Paypal, which is a bit extra due to Paypal charges, but it seemed the guys at Olimex had ignored this bit in my readme.txt. However, they seemed quite prudent in their credit card data handling – it could only be faxed or sent in an encrypted zip file with the password sent separately as a text message. So I chose the latter way of payment, and received a brief “Thanks!” message afterwards in my mail.
I didn’t hear anything from Olimex after the brief thank you, but since the manufacture time was promised to be a week at most and airmail delivery 2-4 weeks after that, I waited patiently. And surely enough, after three weeks, I got a notice in mail that I had a parcel to pick up! The shipment was a normal letter, slightly crumbled outside but its content in excellent condition. All 16 PCBs were tightly wrapped in plastic foil, and looked really good. The total price with extra drill holes, delivery, tax and everything was 46.20€ (about $57), making the price for individual board less than $4 a piece. Not bad!
The quality of the boards was very nice, as you can see in an unaltered photo here (I only added a bit contrast – sorry for the dust, it’s quite an enlargement). I was quite satisfied with my order from Olimex. The communication was short but to the point, everything turned out exactly as it should and arrived in the timeframe promised. I’ll surely be using their services again!
ATtiny2313 header in practice
Once I had the PCBs at hand, I immediately set out to solder one working unit together. However, a slight setback occured in this process: I had used 0.9mm drill holes for the breadboard header parts, and it turned out my finely golded, square 1×10 and 2×3 headers were a very tight fit. I actually had to lightly hammer the headers for the first unit in place. :) I’ve since modified the design to have 1.0mm drill holes for those components. However, I later tried another batch of headers and they fitted without any problem, so even the first batch should be completely usable.
I also tested all the connections with a makeshift battery+resistor+LED+wire -tester and everything worked great, it was time to solder it together!
Putting all components to the board (note that I used a DIP header so I can swap out the ATtiny2313 for another any time I want to) also revealed that the second capacitor is a bit in the way of the 6-pin ISP programming header. The capacitor can either be left out, or one can use longer pins like I did.
As you can see, the header takes up quite a small amount of breadboard space, and the wiring is very simple – one wire for GND, one for VCC and that’s it. In the shot above, I’ve also connected a LED and a resistor to test if everything works as it should (it did :).
All in all, I was very happy with the results of my design process, PCB manufacture and assembly. I can now skip wiring the 6-pin ISP header and crystal to my ATtiny2313 projects, and the project breadboards stay a lot less crowded. For example, I only needed three resistors and an USB cable in addition to the header to work as a USB keyboard!
Extra PCBs available
As said, I got 16 copies of the board from Olimex. I’m saving at least four for myself, but a dozen is available if any readers are interested in the original batch. I’ll make sure to include a numbered and autographed certificate of origin with it. :)
Also, to reward people who donate to the blog, anyone who donates more than $10 (for example, $11) via PayPal is automatically eligible to receive one as long as the supply lasts – just write me after your donation to give an address where to ship it, if you want one! As you can see from the photos, the blog URL is also nicely visible in the design.