I know IgorT makes better drivers than flexdrives. Not sure about their size.
They are pricy though.
I don't make better drivers, i make specialized drivers, optimised for 405nm diodes ONLY! (Size is the same BTW...)
My driver for example can not power a red, because it's just a boost driver in this version (- the full SEPIC version is too big for my needs but fits an AixiZ module), but will keep a 405nm diode at a current that never changes more than 0.2mA (often less) from a full to empty Li-Ion (or <0.3mA from 4.5V down to 2.2V, when tested from my PSU)...
What that means is, that the current through the diode will always be the "same" (it will slowly drift down by 0.2mA as the battery goes from full to empty - a drift barelly worth mentioning).. So the starting power will always be the same as well.... The drawback is that it can't power red diodes in it's current version, nor does it have a pot (but that's on purpose and there is an option WITH a pot). I made it for my lasers, and i'm happy with it.
When i need to make a red, i always use a FlexDrive, i bought many from Lava in the past. I have used a few with BluRays as well, but had some bad experiences with an earlier Flex version (was it v2?) and a PHR set just below a kink (complicated story).. But with improoved stability of the latest Flex and 6x's and 8x's having no kinks, that problem can't repeat itself anymore...
In the latest version, the FlexDrive was redesigned, improoved and made much more stable than before (less current drift), through the selection of more expensive components with better tolerances and better positioning.
And then people complain about the price of it? :thinking:
If i didn't know how to make my own driver, i'd be extatic about having the possibility of buying a tiny driver, so that i can make a small laser working off a single battery - my wish for "small but powerful" lasers was the sole purpose i started working on buck/boost drivers in the first place!
According to Igor, starting with the V4 the current output stability over the range of battery charge is excellent, I think you are referring to old data about the V1-3. For the earlier models, it was still very good but did vary up to 15 mA in some cases. Either model would be much better than the rayfoss ones you link to.
Yes, the latest drivers are much better, than the first i've seen (v2)...
The first ones scared me, cos they didn't like my switching PSU (even tho i filtered it heavily), and i was not even able to test the stability until i put together a battery powered adjustable voltage source.. Then the abnormal operation stopped, and from batteries, they worked well enough.
Adding a few caps on them doesn't hurt either, and i made it a habbit to increase the input and output capacitors, just in case..
I also noticed, that the addition of the right value input capacitor reduces the battery voltage related drift with some of the earlier versions IIRC.
But the v4's i'm quite happy with! Still adding caps just in case tho.
Better safe than sorry.... :angel:
I meant, Igor's driver is MUCH more stable. The output current is more constant from full battery to dead battery.
There are also virtually no spikes.
Ask IgorT about it.
What are you talking about when referring to spikes? And what do spikes have to do with stability?
Every driver HAS to be made in a way that it doesn't have spikes at power-up!
Lava and i talked a lot about drivers, stability and testing them, how to prevent possible accidents from abnormal operation (or abnormal use by the builder) and such...
You can be sure Lava knows what he is doing. He simulated pretty much every possible condition that can occur in a laser, when testing his drivers on a scope, before releasing them for sale!
I got one of the first v4 prototypes, and i have to say i was very happy with it, when i saw the stability was improoved compared to earlier versions! Even better, now i don't have to make two different heatsink versions anymore, since the new Flex is now the same size as my driver...