Previous Posts:
In The Air: Epidose 1: Introduction
In The Air: Episode 2 - Preparing for Surface Mount Work
In The Air: Episode 3 - Surface Mount Beginnings
In The Air: Episode 4 - Inductors
In The Air: Episode 5 - PCB Design
In The Air: Episode 6 - Getting Ready For PCBs
In The Air: Episode 7 - Still Getting Ready for PCBs
Update
I have received some more parts recently, but unfortunately, I am still missing critical components. I'll provide some history of the procurement here so that you can understand why I have not written a blog post in over a month.
- I placed my first order very quickly after being selected as a competitor. My design was going to include many surface mount components, so I ordered the appropriate tools as part of the budget. Everything arrived very quickly.
- My circuit board design was complete, and I was ready to order components.. I placed my second order on Dec 4, 2014. Christmas came and went and I hadn't received any parts, but I figured that was typical of the holiday season. I have been in contact with Christian Defoe doctorcdf27 throughout the process. I'd like to thank Christian for doing all that he could up to this point to ensure I get my parts in time.
- I also ordered some passives from Wurth, and Fed Ex says the parts have arrived, but I did not get them. I ordered some design kits and received those, but the headers and terminal blocks never arrived. Simon at Wurth remedied the situation and the parts are on their way again.
- I used all TI ICs in my design because they are a sponsor of the challenge. I sampled those parts through E14 from TI, but they never showed up. Christian fixed this by ordering what parts he could from Newark for me, and I sampled the rest from TI under my own name.
Latest Work
I made a video showing the population procedure. I've only placed the components I have thus far.
Here's a photo of the board BEFORE cleaning up the extra solder from the reflow process.
Here are two pictures showing the board after removing excess solder. I've plugged it into the launchpad to show how it will look in the end.
I have not powered my board yet because I was only able to sample a single piece for some components. If I destroy the component, it's game over for me! It's also possible I would damage the launchpad. I lack a current limiting power supply, so I'll have to come up with a solution.
Verification
As part of my last order I got an arbitrary function generator (AFG). I thought about it for quite a while, and decided that I indeed should get it. Hooking up a sensor up to an embedded system seems simple, but before anyone should consider doing so, the embedded system needs to be tested with a known signal. Sometimes this is as easy as using a DC voltage source, but for a particle counting system waveforms are required to test the electronics. So, I ordered the AFG because I need to verify that the system works.
I'll hopefully be testing the system soon.... Stay tuned!
