【convoy】H4 and B35AM options are updated

Gotta catch 'em all!

Hi Simon,

I see that S12 UV’s product listing now says 2.4A maximum where it used to say 6A before, if I remember correctly. Does it come with a different driver now?

Hello Simon :slight_smile:
Could it be possible to list SST20-B (and some other 3535 SMT color LEDs that can be used in place of XPL White LEDs) on your store ?

Thank you!

1. It will be available in one week. But the Tc is 5700k instead of 6500k
2. uh ,no plan ,how about M21E? i will add a link of M21E with SFT40 / KW CULPM1.TG in two days
3. It is only suitable for L21B

Can you send me some photos? I want to see how you solder SFT70 and MCPCB.

Maybe in one week.

In fact, the drivers are the same, but this driver was originally designed for SST40 and not for UV LEDs. Because the vf value of uv led is relatively high, the current of the flashlight will be relatively small.

SST20-B?
SFT20?? Do you mean this.

Thanks a lot for your help! Unfortunately the M21E is too big/wide for what I have in mind. The M21B is just perfect other than the lack of onboard USB-C charging.

Maybe others in this thread could chime in if they have an interest in additional USB-C charging lights? I do understand it’s never a simple process to redesign things, but perhaps if there’s a significant community interest and demand, we could see new lights with USB-C charging later down the road?

Simon, I see that Pioneman K80 has been released. It appears to be identical to the thrower you are working on in this post, and I noticed Pioneman has many models that are almost identical to Convoy models. How is Pioneman related to Convoy? Can we expect the Convoy version of Pioneman K80 to be released soon? Has the low current issue with the driver been corrected? Will there be any differences between the Pioneman and Convoy versions of this light?

no, SFT20 is not compatible with XPL MCPCBs

I mean this :
SST-20-B Blue (450 nm) SMT 3.45 mm x 3.45 mm 3.0 A 630 - 830 mW (0.35 A)

(and I am also looking for a green 3535 LED that can handle 3amps with pads compatible with XPL MCPCB)

Like Simon mentioned the Vf of these leds is higher than normal white ones. The 8a driver will only result in higher amperage draw if it also allows a higher Vf. Otherwise as the led heats up it will draw more and more current but not get any brighter. You can have all the amps in the world from a driver but if the vf is low it won’t flow through the led. They go hand in hand.

That’s… Not super clear. I’ll try.

The forward voltage of most UV LEDs is high enough (and goes up quickly enough with current) that you can’t get nearly 8A into them from a single Li-Ion cell without a boost driver. I don’t think they’d handle 8A anyway, but that’s the main issue. For this reason, to really make a high-powered UV lamp you’d probably want to go two-cell with a buck driver. There was a guy around here somewhere running a C8F (for three LEDs) with 2x18650 (via an extension tube) and a buck driver.

Sure, power is ultimately what matters for brightness, but there can be other benefits to different hardware, such as a more efficient driver. I can’t speak as to what drivers are the most efficient in Simon’s lineup but typically running devices such as these at less than their maximum power output results in better power efficiency. That applies to both the LED and the driver itself.

The bit about forward voltage going up as current is applied is new to me. Is that the case on all LED’s or just UV ones? What is forward voltage? Is that the same as Voltage Floor? VF is voltage floor right?

Forward voltage is the voltage needed to overcome the junction bias to conduct and create light. Below Vf you get no current (aside from leakage, but that’s another issue). Above Vf you get current and light.

Look at UV led datasheet here: http://www.s-et.com/upload2/CUN66A1G_R1.0_181016.pdf
Specifically pg 4 Fig 2, you see Vf going up with higher current.

for SST20 datasheet: https://download.luminus.com/datasheets/Luminus_SST-20-WxH_Datasheet.pdf
Pg10, shows Vf going up with current as well. This is just a property of diode.

As above, the forward voltage is the voltage required to push any current at all(*) through the LED. Also called Vf (the f should be subscript but many formatting options prevent that). For all LEDs, this voltage increases with current (otherwise you could have a runaway LED that drew more and more power). There’s other factors in play as I recall, like temperature. But it’s the fundamentals of why some LEDs with higher Vf (like XPL-Hi) are fine with single-cell direct drive, and others are not (Osram 1mm would fry itself).

*: there is leakage current, but this is valid for our purposes

The Vf is what drives the led to allow more amps to flow through it. You can drive leds with constant current unregulated voltage or constant voltage and unregulated current. For the latter as the led heats up it will draw more and more current until it destroys itself. Therefore the safer way to drive leds is to set a current limit and allow the voltage to be whatever it will be. For instance I have a diy 100w light that is really well cooled with a big fan and heat sink. This setup doesn’t need to be current driven I could set the Vf and forget about it. The driver is capable of delivering many more amps than the LED is using but the led will only use more amps if I increase the Vf (voltage differential across the led). Hope this isn’t confusing and somewhat helpful!

Oh and I think a lot of people are confused about how LEDs and current actually works. When you look at some datasheets for LEDs you will see that the Vf is plotted along the x axis aka the independent variable and the forward current is plotted on the y axis aka the dependent variable. This is because the forward current is dependent on the forward voltage.

Hi Simon,

a user has reported a problem with the H1 219b TIR on reddit with the TIR optic not touching the pcb.

https://www.reddit.com/r/flashlight/comments/qmuj8v/convoy_h1_with_tir_tir_not_touching_led/

Do you have any info on that?

Beam as sold:

Beam after pressing TIR on pcb:

More info: