Creating our first light-up 4x4 panel

 Here's our first attempt at a 4x4 light-up panel.
The idea here is to connect all the 5v and ground pins on the panel together, using copper tape, and create a daisy-chain effect from one strip of LEDs to the next


By cutting away at the circuit board, where the 5v and ground pins are, we could create a continuous connection by adding a simple blob of solder from pin to copper strip.

Needless to say, it didn't work!

But that's probably a good thing - because when it didn't work, it forced us to abandon the idea of using copper tape for the LEDs (connecting each to the next using wires at the end of each strip) which allows us to use the same surface for running copper tape for our hall sensor input array.

Our second design was much more successful.


It may be easier to think of this as two panels, overlayed into one space.
Firstly, there's the LED strip, chopped into bits, and connected up again, into a "snake-like" layout




Then underneath this, we have our hall sensor input matrix.
This is a series of criss-crossing copper tape (isolated using masking tape where necessary, to avoid shorting out different paths) which allows us to multiplex four rows of four hall sensors.




Then by simply isolating the hall sensor contacts from the underside of the LED strips, we can place one on top of the other, and have both inputs and outputs on each individual square.






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