If you’ve been following my blog, you know I’m working on an internet-of-things project, having fun and learning a lot. The latest milestone was getting my first PCB (Printed Circuit Board), which was very exciting.
I previously built a circuit on a breadboard for controlling a 12V solenoid over the internet with a Raspberry Pi. You can read all about that here: https://dikuw.wordpress.com/2019/10/20/controlling-a-12v-solenoid-with-a-raspberry-pi/
Then I wanted to convert that breadboard circuit to a PCB so I could design a case to go around it to make an integral internet-of-things device. I have never designed a PCB before, and although I’m sure I could have figured it out, I opted to have the design performed by a real electrical engineer, who I found on Freelancer.com. The freelancer I found is based in the US and did the design for less than $150. I can highly recommend this guy, so if you’re looking for similar help, email me and I’ll connect you: firstname.lastname@example.org.
The standard PCB design comes in a Gerber file. I selected JLC for manufacturing the PCBs because the offer some SMT assembly, which I really wanted because I suck at soldering. More on that in a bit.
Ordering the PCBs is pretty simple: upload the Gerber files, select some options (number of layers, etc.) – I had the freelance engineer help with this and/or choose the default, identify your SMT components and submit the order. It was only $35 for 5 PCBs with 3 SMT components each, including shipping to Vietnam (where I now reside).
Selecting the SMT components was a bit of a challenge. The freelancer engineer had identified part numbers for the resistor, diode, and transistor that I wanted surface-mounted, but JLC has their own database of parts that didn’t line up exactly. I searched the best I could, and then had the freelance engineer verify via the associated cutsheet that the components would work.
Once the order was placed, it was about a week and a half for them to be delivered. Getting shipments in Vietnam is a bit of a challenge, because I live in an AirBnB and don’t speak Vietnamese, but the building manager was able to help me out. The PCBs were shipped from China, and I did get an email from DHL asking for customs information, which was a bit worrisome, but the PCBs came the next day so there didn’t seem to be any customs issues.
So JLC will only SMT to one side of the board, which meant I was forced to attach the converter to the other side myself, definitely the scariest part for me. But I took it slow, and on the first test: success!