Recent content by MegaTesla

What do you guys think about this LED ENGIN UV LED? With heatsink: LZ1-10U600 LedEngin High Power LEDs - Single Color Without: LZ1-00U600 LedEngin High Power LEDs - Single Color

My day job has been keeping me a bit busy lately. I have received some more components and ordered more etch resist ink for my pcb printer, so I will continue with this project in the coming weeks. With the next prototypes I will try to increase efficiency with a different design, and also try...

Don't worry about the off-topic posts. I'm going to be offline for about two weeks, but then it's back to business. I'm receiving more parts then and will be refining the design some more. I do hope this design will be much cheaper than two flexdrives for 445nm high power builds. I will see...

Here is a video clip showing current regulation. In the video I didn't drop the voltage below 3.2V as the power supply current started to max out there. There seems to be about 10-20mA variation in output current over the 3.2-4.2V range. I'm still trying to figure out why... Efficiency is...

The circuit was not designed to work with voltages below 3V.

2A Out @ >5V !! I used a 18350 cell in the photo. I'll tune the loop compensation circuit and check efficiency later. I will also get oscilloscope screenshots of everything that is important when the circuit is finalized. But for now I'm happy that it works with much smaller components than my...

Parts for the 17mm round 1.8A boost driver arrived. I quickly made a single layer PCB for it as I don't want to waste time with the double sided one until I know it works well. I'm going to solder it up now and I will let you guys know how it performs!

I wanted to recommend just an Imax/Accucell charger, but then I realised you would still need a holder for the batteries. I also said "hook it up", I didn't say "put it in" ;) The Accucell (and clones) are quite cheap and they are great value for money. They are fairly accurate. They allow...

I guess I'm just used to charging Lipo packs at 7A :)

Remove the electronics from that cheap charger and hook it up to this: HobbyKing R/C Hobby Store : HobbyKing 50watt 5A X-Charger/Balancer (need external power supply) Fairly cheap solution that is much much better!

A little low output current... And: "DO NOT PLACE THE WRONG CHARGING MODE, OR IT WILL CAUSE THE BATTERY LEAKAGE OR BOMB. "

After a few iterations I was able to fit and route all the components for another driver on a 17mm diameter round (Standard Chinese LED driver size) doublesided PCB. The vias in the picture are oversized as I will be making prototypes myself and I don't have a 0.3mm drill bit. Theoretically...

If anyone is still looking, these are the best 18650's from DX: TrustFire Protected 18650 3.7V True 2400mAh Rechargeable Lithium Batteries (2-Pack) - Free Shipping - DealExtreme I have bought lots of them and they all perform well. Capacity is 2400mAh (unlike most other cheap 18650s). They can...

Good news. I've got parts on the way for another new design that runs at a higher frequency so the inductor (which takes up most of the space) will be significantly smaller. Efficiency should be >80% and the circuit will again be continuous ground with constant current regulation.

That looks like Aixiz dimensions. It will be hard getting a 1.8A driver in there... I'm placing another component order today, so I should be able to make another revision later in the week. At the moment none of the components generate significant heat. I hope to keep it that way when...