Led4power.com : LD-4 CC linear drivers, ILC-0/1 illuminated tailcaps, optics, MOSX, copper DTP MCPCBs...

That explains a lot. Thanks :slight_smile:

led4power, sorry to bother you again. I’ve noticed some annoying oscillation in brightness. It is visible only in 1.5% and 2% modes (checked for 7A and 9A configuration, with and without moonlight enabled). Measurements with multi meter shows oscillation between 135.3 and 136.4 mA (for 7A). Is my driver defective? Can I fix it somehow?

"Oscillation" between 135.3 and 136.4mA is pretty normal because it comes from thermal noise superimposed on useful signal(we're talking about 1-2uV of noise), the real question is how you can see 1mA fluctuation at 135mA current? Anyway,one way to reduce it is to increase signal level from shunt at a cost of increased driver internal resistance.LD-2 to LD-4 drivers have very low internal resistance because at that time there was demand for driver with DD-like resistance on high mode,which was because of high Vf snd generation CREE LEDs. It's possible to reduce that effect by 10times with shunt and one 0402 resistor change,at a cost of increasing driver's internal resistance from ~5mOhm to 14mOhm (still pretty low, difference would be noticeable only if you drive 2nd generation of CREEs close to max. current).

I’m using the driver with triple nichia D240. Those measurements (around 135mA) was taken with cheap multi meter (not high resolution oscilloscope), so maybe fluctuations are bigger and that’s why they’re visible. Anyway - I can live with that :wink:

Hmm, <1%, imho nice result.

Idea: switch that would glow blue when in off position and red when flashlight is turned on (or any other color combination) :smiley:

That is not possible with tailcap switch, because when switch is on, there is no voltage over switch.

Added big gold plated bronze springs:

Gold plated phosphor bronze spring 12x9x1mm

Bottom diameter is 9mm,so they can fit on quite many drivers, switch pcbs etc.

I will try to measure resistance soon, but I expect something like 5mOhm under realistic conditions (~30-40% compression).

Also added new ILC-0 listing with fixed default currents at 1€ lower price:

ILC-0 default currents 4.97€

You still can change current set resistor as you like. Default values save me some time for build, that's why price is lower.

Also, one note related to LD-x4 drivers listings: you can now choose do you want 1mA bleeding or not. If you don't plan to install illuminated tailcaps, it's

better to not have bleeder for two reasons: lower active state driver consumption (1.6mA vs 2.6mA), and 1mA lower sleep current (~40uA vs. ~1mA).

Did you have those springs made? They are about perfect dimension for most tail springs :slight_smile:

(if you had them specially made, that is seriously cool, and having had springs made myself, I’m curious what is the manufacturer. But I’m aware that that may be a trade secret of yours :slight_smile: )

Edit: what is the height of this spring after a couple of compressions?

They are not custom made. They get shorter by ~1mm after 10+ compressions.

Good find then :+1:
And they keep their length well too :slight_smile:

I just finished a build with a LD-A4 and ILC-0 combo, there are some images and details on the mod thread , but overall I can say I’m really satisfied with bot products :beer: . And as soon as the optics arrive I’ll build an e2l with ld-b4 too.

Guess what these are (what makes them different compared to other PCBs), and win pack of 5 (any type)!

Maybe they aren’t DTP boards but still provide good thermal conductivity? For LEDs with thermal pads connected to the cathode, so no need to isolate the mcpcb any more…

The boards are aluminium and central thermal pads are not separate but are connected to led+, so these must be non-DTP boards. And that only makes sense nowadays if the dielectric layer has an extreme low thermal resistance, perhaps the ano-layer type that Clemence also used for his new VirEnce boards?

They look :cool:
Do I spot triple and quad 4040 boards? :+1:

That’s obvious. They’re white. :smiley:

That they are DTP but have isolated the conexions of the FET, temps sensor etc

Negative DTP for the LED and mosfet.

Except copper Noctigon that have direct thermal path (DTP) trough central pad, they are aluminium metal core printed circuit boards (MCPCB) designed and developed from scratch named MOSLED EXTREME or short MOSX. They have pad for external Metal-Oxide-Semiconductor-Field-Effect-Transistor (MOSFET) combined with pad for Negative-Temperature-Coefficient (NTC) thermistor (thermal sensor). This makes them different from any other MCPCBs from market.
There are huge benefits to this design because of true temperature regulation, better dissipation of heat coming from MOSFET thus leading to more reliable operation and cooler running Driver board thus longer runtimes on highest modes.
Also they are 3 times lighter than Copper comeptition because aluminium is used as core material with only 2.3% higher thermal resistance compared with copper DTP competition and 1.5% lower thermal resistance compared to non-DTP copper MCBCBs.
Another thing to note is that currently there is no other MCPCBs on market that support 4040 LED footprint in form of single, triple or quad configuration, especially combined with pads for MOSFET and temperate sensor!
Also there is support for Osram Oslon Black Flat that is known for not having electrically negative central pad and support for Lumileds Luxeon Z ES!

MOSLED EXTREME boards (the white ones) have chemically grown aluminum oxide(alumina ceramic) layer as insulation which is excellent thermal conductor compared to classical MCPCB insulation layers ( basically epoxy+ ceramic powder), performance should be pretty much "DTP - like" for LED applications.

Advantages over copper DTP are:

  • electrically insulated - it's possible to use LEDs with electrically non-insulated thermal pad,like OSRAM Oslon (both IR and white), while maintaining DTP - like performance
  • very flat surface - this is important for very small LED packages
  • lower mass - may be beneficial in headlamps
  • high temperature resistance - because there are no laminated epoxy based layers, there is nothing to "melt",burn or de-laminate, board can be re-soldered many times without degradation

Disadvantages:

  • harder to solder wires - this is because whole PCB is thermally conductive, unlike DTP, where only central pad is very conductive

So djozz was correct (again), Jos please send me PM with address.

There are 9 different versions of mosX boards: 3535,4040,5050,7070,3x3535,3x4040,4x4040,OSLON/LUXEON IR, LUXEON ZES, I will put them on web page soon.

LIke MOSLED pcbs, these boards should be very convenient to drive low Vf LEDs,or in any case where dissipation in mosfet is high (XP-G3,XP-L2,Lux V,SST-40, XHP50.2,XHP70.2,XHP35...) in combination with LD-B4 driver.

I don't know if Luxeon V even fit under Carclo optics,I will try that later, but I'm counting on domless version release of Lux V, sooner or later.

I will do some tests vs. DTP when I find time,but based on older MOSLED pcbs test (mosled extreme has ~7-10times better performance vs mosled), I think difference will be hard to measure.

BTW, OSLON/LUXEON IR version doesn't have pads for mosfet because these LEDs have relatively high Vf, so there is no need to use LD-B4 with separated mosfet, power dissipation is not very high.