SST-90 True CC Driver 10 Amps Hi/Lo Mode

[keith p]

Looks great! Can't wait for these to hit the market!

 

[sector_cleared]

Hey guys,
thanks for your support. That is what I love about this forum. Funds are not the the problem at the moment only sparetime to work on the driver :sick2:

I was able to solve the ringing problem. I hope I will be able to find some space on the board for the additional parts that I need for that. I am looking forward to get hands on that new FETs. Hopefully on monday
@parawizard: Actually I dont want to share which controller I am using. I am quite ambitious about this project and since I have a competitor I wouldnt be smart reveal that. Please dont get me wrong ;-)

 

[stinky]

@parawizard: Actually I dont want to share which controller I am using. I am quite ambitious about this project and since I have a competitor I wouldnt be smart reveal that. Please dont get me wrong ;-)

When you are finished I hope you make some money on these. You are doing a lot of work and deserve to get paid for your expertise and effort.

If turns out to be really great, someone will inevitably reverse engineer your product at some point. In my opinion there is no reason to accelerate that process.

 

[Techjunkie]

In other words, we wont hold it against you if you scratch the markings off of all the chips before you photograph/ship the drivers. 🙂

When you are finished I hope you make some money on these. You are doing a lot of work and deserve to get paid for your expertise and effort.

If turns out to be really great, someone will inevitably reverse engineer your product at some point. In my opinion there is no reason to accelerate that process.

 

[The Dane]

In other words, we wont hold it against you if you scratch the markings off of all the chips before you photograph/ship the drivers. 🙂

Yeah, it aint them there numbers and letters that makes them cetipede liquorice'sses do their mojo anyway:lolsign:

 

[netprince]

I'm not particularly interested in purchasing a board with markings scraped off, not that I would know how to do anything with the info anyway, its just the idea. Its not a $3 driver from dx.

IMHO the best way to hide the markings would be to ship it attached to a heatsink. Something with this much power should be heat sinked anyway.

 

[heffay]

marking my territory for later when driver is finished :naughty:

 

[nailbender]

Hi
I will be glad to buy a few and you can paint mine black if that is what it takes.

I can totally understand you keeping details to the driver. It is your knowledge , money and time. I am thrilled you are helping us out and I seriously hope you can make some profit.

We are lucky to get this chance and our bonus is we don't have to buy 500 to get them made.

Thanks for your efforts

Dave

 

[sector_cleared]

Good news guys!

Those new FETs kick ***. I soldered them on the prototype pcb today and it boosted the efficiency from 83% to 88.5% Thats far more than I expected. Unfortunately the new FETs didnt reduce the ringing too so I will have to implement a few more parts as I posted before. Last task is making the two level current control work and then I can do the improved layout.

 

[joethefish]

Hey good work I found this thread after asking for some advice in the divelight section for a SST-90 aspheric dive torch im planning.
The only thing holding me back from getting cracking is the lack of a decent driver.. which hopefully you'll be able to help me with soon!
If it helps you at all.. or means I can get my hands on one sooner I dont need a two power level mode.. full whack or nothing for me :twothumbs anyway I wont PM you as i'm sure your inundated with them but if you can help out with that then let me know.. if not i understand you have enough to be getting on with 😀 but please let me know as soon as I can buy one.. dive season is looming and im without light!
Joe

 

[georges80]

Any idea what the dissipation of the LT3743 is when driving the FETs. I'm interested to hear if you have any idea of the losses in the LT part (most would likely be gate drive related), the inductor and the FETs.

I wonder if the performance would be better if you connected the 2 FETs closer and/or on the same side of the PCB to get directly to LG and HG on the controller IC.

Nice job so far.

cheers,
george.

 

[netprince]

Good news guys!

Those new FETs kick ***. I soldered them on the prototype pcb today and it boosted the efficiency from 83% to 88.5% Thats far more than I expected. Unfortunately the new FETs didnt reduce the ringing too so I will have to implement a few more parts as I posted before. Last task is making the two level current control work and then I can do the improved layout.

Very cool sector_cleared. Whenever your ready, I'm interested in two boards. 🙂

 

[Aircraft800]

Is the possibility of a 2 level 5A driver still doable with the new FET's? The SST-50 has been real good to me, but DD it all the time is going to cause a problem in the long run.

Thanks for all of your hard work, you even caught the interest of George (TaskLED) ^^^^^ Nice Job!!

 

[sector_cleared]

@george: I dont know how it is with the LT3743 but in my case the losses due to the gate drive are not very high. I am using FETs with extremly low gate charge to reduce transition losses. The nice side effect is that the dissipation in the controller is also quite low (~150mW).

I wonder if the performance would be better if you connected the 2 FETs closer and/or on the same side of the PCB to get directly to LG and HG on the controller IC.

Normally I would agree with you. Short tracks is the way to go. But in my case the shortest way was to place the controller IC directly underneath the FETs. I have a via which gives me some parasitic inductance but definitely not more than the longer track would have had. And one of my goals was to fit the pcb in a C-sized Mag and I doubt it's possible to squeeze all that stuff on one side of the pcb.

@Aircraft800: Of course it is still doable. The FETs are just dissipating less of our valuable energy 😀

 

[Codiak]

And one of my goals was to fit the pcb in a C-sized Mag and I doubt it's possible to squeeze all that stuff on one side of the pcb.

Are the primary issues now a matter of form over function?

 

[nuggett]

whats the diameter of the board?

Duh, first post......" Diameter 26.2mm / 1.030" (fitting a MAG C tube!!!)"

 

[Linger]

Aircraft800,
(minor thread jack) - could you just put a 2nd switch in. One side is DD, side two runs it through a multi-level board for drive currents >2.5A

(end ot)

 

[ergotelis]

sector cleared, make them fast!We need them! Don't make us spend $400 on SR90! 😀

 

[bradsab]

Waht is the overall height of this driver?

 

[nuggett]

driver height is on post 77

"It is 10,5mm"