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

Double tap is just shortcut, so if you have 4 modes and 2x tap to high enabled, modes will work 1-2-3-4 just as usual, 2x tap mode jumps to mode 4 from any other mode.

About S41 optics, if it's different than carclo then it would not fit. I have several more mosX boards on my wish list, I could add S41 to that list too, and make them in next batch, but I need detailed drawing of such board.

Unrelated to this, I have soldered Luxeon V LEDs on mosX 4040,3xV,4xV with soldered LED wires ready to use, I just need to list them on my page.

Coupon codes for larger orders:

L4P-3of50 3€ for every order over 50€

L4P-10of100 10€ for every order over 100€

L4P-25of200 25€ for every order over 200€

L4P-45of300 45€ for every order over 300€

@ led4power
Any idea when you will have the Luxeon V on 16mm DTP mcpcb back in stock?

~3weeks.

I just placed an order for some quad MCPCBs with Luxeon Vs but I didn’t see any tick box anywhere for reflow service, neither did I see any place to add message on placing order. Is reflowing the LEDs onto the MCPCB included? If not, do you offer reflow service? What would it cost? I’d like my the LEDs reflowed if possible.

I'll put listing with soldered LEDs as soon as I find time, until then you can order LEDs and mosX separately,and leave note about soldering LEDs, no extra fee for soldering.

It’s the order placed to Sweden at about 23:30. I can PM you order number if needed.

A question about the MOSFET option for future orders if I may. The MOSFET that you put on if option is selected, is it specific for your drivers? I’m wondering if I could use it for mine own drivers as a full on boost mode and get similar results as with the SIR800DP.

OK,I see it.

MOSFET is just that, mosfet, you can use it with any driver that use mosfet, DD or linear. It has 2,4mOhm resistance, one of the lowest in LFPAK33 package,and should be good in most cases.

Even with DD drivers, having mosfet on LED board is beneficial because:

-it saves space on driver board (more space for other things),

-Even on "DD" mosfet has finite resistance, if mosfet is on driver PCB at 10+Amps it would generate enough heat to make internal uC temperature reading wrong/problematic - with mosfet on LED pcb there is nothing left on driver pcb that could generate larger amount of heat, so temperature sensing with internal uC sensor is much more predictable.

What’s the current limit of this mosfet? Is it good for 25 Amps with single cell DD?

25A without problem. Power dissipation in that case is 3-3.5Watts, this is no problem on any mcpcb. On the other side 3+ Watts on driver's FR4 pcb would cause melting if there is no additional thermal path (silicone cubes etc.). Internal uC temp. sensing would be pretty much useless for thermal regulation/stepdown.

Thanks for the info!

To find out resistance of spring that I have for sale HERE

I used rigol DP811 in CC mode at 1,2 and 3 A and measure voltage drop with 4-wire method.

Djozz did similar test for few springs quite long ago: https://budgetlightforum.com/t/-/29825

I measured resistance for 3 other springs to check consistency: convoy steel spring, fasttech bronze spring, Intl-outdoor beryllium short spring.

Results are:

Convoy steel spring:

1A 43,5mV :R=43,5mOhm

2A 86,4mV : R=43,2mOhm

3A 133mV : R=44,3mOhm

Avg. resistance: ~43.7mOhm

Fasttech bronze spring:

1A 22,5mV :R=22,5mOhm

2A 44,8mV : R=22,4mOhm

3A 67,2mV : R=22,4mOhm

Avg. resistance: ~22.4mOhm

Intl-outdoor beryllium short spring:

1A 7,4mV :R=7,4mOhm

2A 14,63mV : R=7,32mOhm

3A 22,5mV : R=7,5mOhm

Avg. resistance: ~7.4mOhm

Phosphor bronze spring 12x9x1mm

1A 13,4mV :R=13,4mOhm

2A 26,82mV : R=13,4mOhm

3A 40,5mV : R=13,5mOhm

Avg. resistance: ~13.4mOhm

It's obvious that measurements are very consistent and independent of current.

At higher currents resistance of steel spring starts to increase due to temperature rise caused by power dissipation.

Intl.outdoor spring has smallest resistance, but it's also the shortest,and not very "springy".

Conclusion is that 12x9x1mm bronze spring is good for currents up to 6-7Amps without need for bypass, which should be perfect for medium (by today's standards) lights, or for SRK-like mulitcell lights.

Spring is big enough to add bypass of course, good thing compared to bypassed steel springs is in case of bypass failure spring has still very decent conductivity and probably won't melt,unlike steel springs.

^ :sunglasses:

Thanks for the testing led4power. :+1:

Very nice, thanks for testing!

I have to say, you’re doing an amazing job offering specialty products which precisely cater to the unique needs of modders on the flashlight forums! You fit in perfectly with some of the other guys like Clemence and Lexel (and maybe the Sandwhich Shoppe 10-15 years ago). Everybody has their own niche where they offer their unique products. You seem to be especially motivated though to offer stuff that has never existed before and is very practical. And all of that for such nice prices from a guy who knows what he is talking about. :wink:

Finally first LD-B4HV test (Luxeon M 6V version as test LED on 20mm 4040 mosX, 6A LD-B4HV):

6A high mode, top side of mosfet is still cold:

Two 6V Luxeon Ms in series as simulation for 12V (4S) LEDs like XHP-35:

6A high mode, 16.4V input, around 100Watts input/output power:

I will try XHP50.2 in Convoy C8 host with LD-B4HV and 2x18350 Aspire cells soon.

Have I missed something or is this your new 2S/3S driver? Side switch capable?

Yes, this is 1S-4S variant of LD-B4 (1S only). Side switch will be available later, it's supports clicky switch for now.

It is capable of driving a 3v led with 1s, 2s, 3s and even a 4s battery setup? Without needing to change components on the driver?

Or is 1s still limited to 3v LEDs and 2s to 6v leds and 4s to 12v LEDs?

It can drive 3V LED with any voltage up to 20V, but this is linear driver,it burns extra voltage into heat. This driver is good when voltage of LED and battery are similar, like 2S cells and XHP50.2, XHP70.2.

In combination with mosX MCPCB generated heat in mosfet is not problem at all,since it's well cooled on mosX. Second generation of XHP50 and XHP70 have very low forward voltage, so they draw too much current with DD drivers which can lead to LED death or at least low efficiency because of too high current. Efficiency is equally bad in all modes that are derived by PWM of DD mode. Also 7135 regulators have max. operating voltage lower than 8.4V, so reliability is questionable when they are used in 2S setups.

This drivers provides constant current on all modes, so there is no problem with too much current on high mode, LED efficiency is max. possible in all modes. Disadvantage of CC method was extra heat generated in driver(mosfet to be precise) - that is completely solved with mosX board because mosfet is on same MCPCB as LED.