So, why this project and why now?
I generally get project ideas before looking for components. For the whistled, things were the other way around.
A few months ago, when finding a new 32pins Cortex M4 
, I got plenty of ideas and the whistled was one of them.
As mentioned in the video, this tiny Kinetis K10 can perform around 80 [q15 2048 points] Fast Fourrier Transforms (FFTs) per second and still give me time to run my own algos.
This is explained by the fact that a Cortex M4 has a Digital Signal Processing (DSP) instruction set which is particularly useful for processing operations, and also because the ARM CMSIS library provides us with already optimized code to perform more complex functions such as FFTs.
As all the ground work was already done, I could actually focus on filter design and whistle recognition algorithms.
This took a lot of time and a lot of testing.
All the PCB traces you may touch are ESD protected: namely the power supply and the N-Mosfet drain, as all the rest of the PCB is covered by a transparent heat shrinkable tube. I really wanted to idiot proof my design (no offense intended).
Something worth noticing is that the Kinetis K10 has a 16bits timer with PWM outputs, resuling in a wide dimming range.
The platform will allow you to apply from 4.5V to 18V, with a max current of 5A at its input.
You could actually drive up to a 90 Watts load with this tiny 55x13mm board!
And of course, SWD pads are present on the board for you to flash your own program.
For more detail: The whistled: how to remake a dozen years old project the right way
