We found a mini Bluetooth dongle and just had to see what was inside.
The final class of the SparkFun summer semester is tonight! Come join us for a class on selling your widget
I'm not sure if you've seen these little jobbers on the market. It's an itty-bitty Bluetooth dongle meant for laptops. Above, you can see the small nub sticking out of the side of my HP Mini 1000, which absolutely rocks, but does not have Bluetooth built in.
Depending on where you buy, these little guys range from a few dollars to $50! But what is the world could be tightly packed underneath that little cover?
They must have folded the PCB, stacked the dies, used a mechanical turk
inside or managed some sort of magic. That's just amazing!
I figured the entire thing would have been one potted glob of black resin, but with a handy razor blade, the housing split open surprisingly easily. That is one heck of a PCB trace antenna (2.4GHz).
The engineering was surprisingly good! The PCB slides inside the small metal housing, that acts as the USB connector and doubles
as an RF shield. Very sneaky. Here you can see the 12MHz crystal (for USB communication) and a simple 3-pin SMT voltage regulator (I assume 5V down to 3.3V). There is also a basic LED on this side of the PCB that barely lights up and can be seen through the smoky, semi-transparent housing.
And here's the magical all-in-one Bluetooth IC! AS3620QA is the IC. Not sure how much this actually has built into it, but it is pretty neat! All wireless technology should be so easy!