Emisar D1S Oslon Black flat mod 340k+cd

Nice. Is that the D1S with XPL HI in the comparison shots?

Yes it is! Just updated the thread to say the comparison light

That’s a nice tight beam right there :slight_smile:

I always thought those were very expensive but I guess not, quite a surprise at under $5…
That is just awesome, you should be able to light up some satellites going by with that D1S…

I thought the Oslon black flat were weird to feed, like with a P-Fet or something :disguised_face:

wait, isn’t Stock MCPCB is DTP
did you also change the driver?

“shaved down the centering ring to fit the new LED”

What do you mean by shave down? Because the LED is sitting lower than the XP-L HI?

The data sheet Vf is 2.75(min) 3.05V(typ) 3.75V(max) at 1amp. Rated forward current is 50-1500mA. Maximum rated pulse current is 2.5A.

He’s talking about the thermal pad not being electrically insulated.

[quote=LichtAn]

Ahh. I’m still learning.

From the data sheet:

So, any explanation ?
Is it as simple as a reflow on the stock Noctigon and voilà ?

My best guess:
A lot of non-conductive thermal paste was used and the DTP-MCPCB is just isolated from the driver by sheer luck.

Otherwise you would need an isolated MCPCB as those from led4power which use a special aluminium oxide layer to have near DTP-performance on isolated MCPCBs

Yeah I was thinking the same… Heat path is not ideal in that case :frowning:

This might be 100% wrong. But I vaguely remember someone saying that the Emisar boards have a P-FET?

Very cool build mikelights. Congrats

This might be the same emitter at Arrow for lower cost and free overnight shipping:

https://www.arrow.com/en/products/luwhwqp-8m7n-ebvf46fcbb46-1/osram-opto-semiconductors

EDIT: I just read here that there are what sounds like higher binned ones at mouser and digikey, but I can't seem to find them. I can't seem to match up the manufacture's part number to the datasheet. The listed specs appear to indicated the highest light output, but also highest Vf. They are only showing max's though. So not sure about that.

EDIT2: Please disregard the struck out text. Member Nicolicous alerted in Post 31 below that this is a 5-pin package that may not be compatible with XP based.

Cool.

The Emisar lights don’t have a p-fet driver .

The explanation : the driver’s ground , isn’t connected (electrically) to the head , but only the tube is , that carries the Battery (-) .
That allows the head to be connected with Led (-) without causing issues on the driver .

Annnnnd thank you very much for that clear explanation, I couldn’t for the life of me figure how it was possible.
You couldn’t do that in, say, a C8…
Now I have to order some black flat :person_facepalming:

True about the head being isolated from battery negative. I didn’t think of that. But I wouldn’t necessarily rely on this method of isolation because if the anodization of the tube threads wears off it’s no longer isolated.

A method to isolate the MCPCB from the shelf that’s worked well for me when I was experimenting with making XD16 arrays is using narrow strips of kapton as spacers under the MCPCB. A couple small strips (~2mm x 15mm) near opposite edges of the MCPCB prevent any metal to metal contact. Put the strips on the MCPCB and use ceramic thermal paste as usual. The kapton thickness is only 50microns so it’s practically not adding any thickness to the thermal paste junction.

This is a rare occasion , since most people change battery from the tailcap side . Someone could add some (veeery little) medium strength threadlocker to be sure they won’t change battery from this side , and so it won’t wear off .