5 Watt 445 driver?

[Wmacky]

I'm in the information gathering stage of my next build, and I'm thinking about the driver. I'd like to run this latest 445 at between 5, and 6 watts. My understanding is the driver selection for this duty is bleak! I'd like something that could easily handle this current without short duty cycles, or short life spans. I plan to sink it if possible, and I'm looking to provide it with power from 2 26650 cells.

What are my options? I've read of a custom X-drive that hard to obtain?

 

[IsaacT]

I am in a similar boat so I am going to subscribe and see what comes of it. From what I understand, as far as buck drivers go there isn't anything on the market that can be driven in parallel for higher amperage. And of course boosting is going to be more inefficient I believe. Or atleast very short battery life with a high discharge.

DTR has drivers that do 3.5A, but that is only going to be enough for 4.8W or so. 4A appears to be the desirable current to run these.

 

[rhd]

I am in a similar boat so I am going to subscribe and see what comes of it. From what I understand, as far as buck drivers go there isn't anything on the market that can be driven in parallel for higher amperage. And of course boosting is going to be more inefficient I believe. Or atleast very short battery life with a high discharge.

DTR has drivers that do 3.5A, but that is only going to be enough for 4.8W or so. 4A appears to be the desirable current to run these.

Do you have an NDB7A75 that you're waiting on a driver to be able to use?

Is 4A the ideal current on these?

 

[IsaacT]

4A is what people want to run them at. I haven't bought my diode yet but I will be in the coming week. Got a special build in the works 4A pops it over 5W but isn't the max that it has been tested to. I think max tested was like 4.5-5A

 

[rhd]

4A is what people want to run them at. I haven't bought my diode yet but I will be in the coming week. Got a special build in the works 4A pops it over 5W but isn't the max that it has been tested to. I think max tested was like 4.5-5A

I've got a thread in the driver section somewhere about my 5A buck. Paul scoped it, said it was completely clean, no substantial ripple, or bad stuff at startup.

I wasn't going to release it / open source it since I thought there was already a high current X-Drive available to the forum. Am I wrong about that?

If there are genuinely no 4+ Amp bucks, then I'd be open to releasing mine.

 

[IsaacT]

I believe the max X-Drive we have now is a 3.5A one. If you have a 5A capable driver that would make some waves on the forum! I take it they would need to be manufactured?

 

[rhd]

I believe the max X-Drive we have now is a 3.5A one. If you have a 5A capable driver that would make some waves on the forum! I take it they would need to be manufactured?

I don't know - I'm not a manufacturer, and I have zero intention to manufacture or sell anything.

I just made the driver for myself because I needed something small for driving MT-G2 LEDs (they can pull 5A and have a Vf of 6 or 7 Volts). Though small is relative. It's not tiny, it's still somewhat sizable.

 

[IWIRE]

I'm not aware of anything available to run this diode at over 4a. I had to use two boost drives to power mine. It would be awesome to do a build with a buck drive. With boost drives mine is pulling almost 6a at the tailcap.

 

[Wmacky]

Interesting. So for max output builds, people have been doubling up drivers and boosting from a single cell. I don't care for that idea very much due to the excessive amp draw at the input. I may have to hold on this build until until the community finds a better solution. That or settle for the 3.4 amp driver. I understand that at 3.4 amps, reaching 5w may not be always possible with every diode?

 

[jander6442]

Just parallel 2 2A X-drive....viola.

 

[IWIRE]

Interesting. So for max output builds, people have been doubling up drivers and boosting from a single cell. I don't care for that idea very much due to the excessive amp draw at the input. I may have to hold on this build until until the community finds a better solution. That or settle for the 3.4 amp driver. I understand that at 3.4 amps, reaching 5w may not be always possible with every diode?

It`s pretty funny. The dual boost drives with one 18650 battery actually wound up working better than the one I just bought already built. The key was eliminated all voltage drop in the build and use an Imren 18650 battery.
I also built one set at 3.4a. Seems like I got 4 something watts. There is a thread somewhere on that build called Jackie Blue.

 

[upaa27]

Lazereer has some really nice drivers although I don't think that they can drive the diode with the power you need. I think your best option would be to do a dual diode build

 

[rhd]

Just parallel 2 2A X-drive....viola.

Excellent suggestion - there's the solution!

 

[IsaacT]

Excellent suggestion - there's the solution!

A number of people were told to NOT parallel those drivers. Anybody with a bunch of knowledge want to explain why it is either a bad or irrelevant or good idea?

 

[rhd]

A number of people were told to NOT parallel those drivers. Anybody with a bunch of knowledge want to explain why it is either a bad or irrelevant or good idea?

Told by whom, and for what reason?

Unless it was Angelos saying so, or someone with a scope who observed a reason not to parallel, I'd take it with a grain of salt.

What is true, is that often when you parallel drivers, you end up paralleling the SET resistors, which means there is no guarantee that the individual drivers will split the load equally.

 

[IsaacT]

According to DTR, Angelos told him not to.