Slow progress

Just a little heads-up for the time being: This is one of the things I am currently working on. I have some things with DFN-packaged parts in the making, this also belongs in that category. The IC is a Texas TLC5941 16-channel programmable LED pwm controller, and the whole thing will be an ambilight system that can be easily scaled by adding more of these stripes. Each stripe will contain 5 individually adressable RGB-LEDs, equal to 5 individual zones. The master signal will be delivered by the pc (no, unfortunately I have no plans in stock to decode VGA or DVI so far, as this system is inteded purely for pc-aided use) via serial comm and formatted by an Atmel ATMEGA to fit the daisy-chaining protocol of the TLC chips. This also means that additional boards can be connected without much hassle.

Ambilight preliminary pcb

Hopefully, I can produce the first PCBs myself. The biggest problem are the through-hole contacts, but I guess this can be done using 0,6mm contact rivets. Of course, I am in no mood to do this for all the 50-some boards that will be needed – I am not the only person interested. The angled pinhead connectors at both ends will be replaced by rows of soldering pads so that two pcbs can be soldered together without a gap. Alternatively, they can be connected by soldering flat cable or even single wires in between.

I already have all the necessary chips and a whole lot of LEDs for some prototype boards, but I need the reflow oven to work properly for this – the chips are DFN, as mentioned. I soldered one of them bottom up to some pinheaders using thin enameled wires: Avoid if you can, it’s NO fun at all! The chip survived the torture, surprisingly.

Hopefully I can make some progress on the oven tonight. I already equipped one of these things with a diy controller before for a friend, so the software is kind of done.

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