I got my FWAA a few days ago and had my fun with it so I’ve decided to do a tear down in preparation for future modifications I have planned. In keeping with the BLF spirit, here’s all I found:
I don’t have a clamp meter so I measured the current the emitters are pulling by using a method I recently read about where you measure the voltage drop between the mcpcb leads. I measured 3.3v which correlates to 3.1A per sst-20, totaling 9.3A with 3 of them with a fully charged vapcell H10. This little 14500 is a monster! This measurement may be incorrect though as I partially killed one of the emitters when my multimeter’s probe slid and touched the wrong thing.
Has anyone ever seen an LED die like this? My LED’s die died.
There wasn’t much thermal paste below the honking fat mcpcb. It’s 3mm thick and is easily the chunkiest mcpcb I’ve ever seen!
Just as the mcpcb is thick, the driver cavity is shallow. I measured it to be around 3mm or less. This is a fet+1 driver, controlled by an attiny85 with the reset pin left unsoldered. First time I’ve ever seen this, maybe it saves a few pennies over the entire production run?
The driver is a double sided 1.6mm thick board which looks machine reflowed on both sides. With my limited knowledge of pcb production, I believe they reflowed the top side while the spring side passed through a wave solder machine? Actually with the spring there, that’s probably not what happened so I’m really not sure how these double sided boards are produced. I suppose the spring is probably hand placed and hot air soldered since a pick and place machine probably can’t handle a spring? Maybe one of you more knowledge peeps can enlighten me?
Regarding the cleanliness of my FWAA, it looks like the driver pcb went through a proper pcb wash cycle but they didn’t bother cleaning the flux after hand soldering the mcpcb wires. It’s a shame because the dirty stains on the mcpcb are the only ones most people will ever see, and pass judgment with.
Here are my measurements of the driver board. I reckon they’re accurate to about +/- 0.1mm. I think thefreeman might have been interested in these figures so I’ll just include them for everyone. It’s a tiny driver, really not much space for anything but passives on the spring side. The ones lumintop used look to be 0603 sized components.
And finally, the FWAA comes with a new spring in the tail switch that the Fw3a didn’t have. I’m not sure if it makes a big difference. It seems to be not very stiff, but I guess if you don’t screw the retaining ring too tightly, it can allow the switch pcb to move just a tiny bit, allowing for some looser tolerances of that signal tube?
I’m not sure how much it helps but it is a new addition (to my knowledge) not seen on other FW3A variants.
Cheers and I hope you enjoyed this quick look at the FWAA’s innards. Please excuse any errors as it’s past my bedtime and I’m quite tired.