August 08, 2018

Loyal Backers,

We have new circuit boards! Check them out below!

These are two separate panels of boards and in total there are actually 5 boards in the panel. The display board, button board, carrier board, USB A, and USB C boards.

The main panel

The back of the main panel

The USB panel

In order to make these boards function we need to put components on them. We have a BOM (bill of materials) which is a list of all the parts that go onto the circuit board to make it work. Basically, every gold pad will have a component or wire attached to it in order to make these boards work. The Doppler bill of materials contains 55 different types of parts ranging from Ambient light sensors to USB ports (not quite A-Z). In total there are 438 total parts on the Doppler's boards. Holy cow! Some of these parts are very small making a penny look big.

This is a 0402 part. Meaning it's .4mm x .2mm

These panels are then taken to a board assembly house along with the parts and they are installed on the boards using solder paste and reflow ovens. This consists of taking a laser cut metal stencil and using it to expose just the gold pads. Then you take a liquid metal material called solder paste and carefully dispense a tiny bit on each of the exposed pads of the circuit board. After that, each of the 438 individual components must be manually placed in the proper orientation on the pads filled with solder paste (during large-scale production this is done by a machine). Lastly, you place the boards into a very special oven called a reflow oven which melts the solder paste attaching the parts to the boards and creating a good electrical connection. This process is basically how all circuit boards are made! It's pretty fascinating!

Here are what the boards look like once they come back from the board assembly house:

Main panel - front

Main panel - back

The biggest difference with these boards is the inclusion of the PicoSOM and the removal of the Chip Pro. But, there are a lot of other changes and additions as well. See if you can spot some of the differences. Here is the update where we broke down parts of the boards, see if you can see any of the big differences!

Comparing the boards, both in panel

Once we got the boards back from the assembly house, we attached wires to the inputs of the boards and attached the flex cables to connect the boards together. When powering up a new board design for the first time you always have to be very careful since there are so many different places things can go wrong.

A closeup of the flex cable connecting the button and display boards

We are happy to report that the boards powered on fine and everything looked to be in order. We flashed the latest firmware onto the microcontroller and turned on the lights!




Then we have to test fit the boards into the plastic parts. Check out some pictures of the boards inside the plastic:

All 5 boards are pictured here

A closeup of the carrier board

The boards that were in the main panel

Looking good!

So? What's the next step?

Next, we have to continue working on getting our software onto the PicoSOM and work on getting our boards to talk to each other. We hope to share some great news in the next update regarding this progress.

While we have been doing all of this we have also been working on the smartphone app, the Doppler software, and the mechanical tooling changes discussed in the last update. We plan on sharing the progress we have made in upcoming updates!

A quick note, a fair number of you have asked: How can I change my address? Is it too late?

No, it's not too late and you can change your address in Backerkit by following this link (Indiegogo | Kickstarter) and finding your pledge using your email address. From there you can change your address. We will let you know when we will be "locking down" addresses. But, for now, assume it will be in October.

We are working as hard as we can to get you the Doppler as fast as possible. Thanks for your patience.


The PAI Team

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