Drivers for 445

drlava said:

LazyBeam said:

Browsing around a little more... these might work well for hosts to just replace the stock pill boards.
Guys, would these do the job? They step up so use with 1X 18650 should be OK, right?
The only thing that seems odd might be the BB Nextgen and its "safe mode"... any opinion on this??

GD Buck/Boost Converter Blank $18
Sandwich Shoppe
* This converter will step up or step down
* Minimum Vin: 1.8V
* Maximum Vin: 5.4V
* Maximum Vout: 5.4V
* Full Constant current regulation.
* Output adjustable: Two 0603 resistors

BB Nexgen Blank $15
Sandwich Shoppe
* Output adjustable: Two 0603 resistors
* Maximum Vin: 6V or Vout (which ever is lower).
* Maximum Vout: 6V or Vf (which ever is lower).

Badboy Step Up $14
Sandwich Shoppe
* Minimum Input Voltage: ~1.6V
* Maximum Input Voltage: 3V (1W/3W Luxeon) & (6V 5W Luxeon)
* Output Set by resistors

Click to expand...

because those LED converter boards weren't designed to drive laser diodes, they don't have as much filter capacitance as the MicroBoost and FlexDrive, which will lead to current spikes on the diode. For LEDs, that's OK but it can shorten the lifetime of laser diodes. Looking at those LED converter boards, you can see that fewer capacitors are used.
...

Click to expand...

What sort of capacitance do you think is an acceptable amount of protection for LDs... (uF@V)?

If we plan on using these drivers would/could we be a little more safe if we attached one or two small capacitors across the diode output leads?
I'm hoping one could get the advantage of using a driver that fits in most 18650 hosts with a simple board swap but still get decent LD protection.
Being able to replace a host's boards with one of these could allow for a much larger heatsink (not having to make room for flexdrive/microdrive.
At least this is my plan if/when my 445 diode ever shows up... 750mW in an a Jayrob 18650 host with extra big Cu heatsink.

I'm interested in the parallel Lava drives as well. Anyone care to make a diagram? I'm terrible at understanding the utilization of electricity.

Edit: And just to verify, a Flex v5 @ 1.5A will work with one 18650? Does it need heatsinking?

So can you use a 1ohm 2W resistor (if found) in a LM317 circuit to make the current set at 1.25A, and if so, will it be able to run off of 3x 10440 batteries? (will it be able to draw enough current, or will something burn or explode?)

Even a 1 ohm 1.5 Watt resistor will probably be fine...

1.25(voltage at LM317 sense pins) X 1.2 (Amps) = 1.5

So 50mA's over will be fine...

But 3 X 10440's in series will be a very small capacity for a 1.25 Amp current draw. (if they can even handle that)

But 3 X 18650's will handle the current draw as long as they were quality batteries. I found that AW brand are the ones to get...

Just thinking about this circuit makes you really appreciate what the tiny Micro BoostDrive can do with a single 18650 battery doesn't it? Awesome driver...

Sooo, which one ?

Flexdrive
OR
Microboost

For a 445 at 1 Amp

Tabish said:

Sooo, which one ?

Flexdrive
OR
Microboost

For a 445 at 1 Amp

Click to expand...

I suggest reading.

Exerd said:

I suggest reading.

Click to expand...

They both seem fine from the specs I checked. I'm guessing the microboost might be more efficient at 900ma?

ZRTMWA said:

I'm interested in the parallel Lava drives as well. Anyone care to make a diagram? I'm terrible at understanding the utilization of electricity.

Edit: And just to verify, a Flex v5 @ 1.5A will work with one 18650? Does it need heatsinking?

Click to expand...

From what I've read and been told (I have no past experience), a Flex can go to 1.5A, but it cannot support a high voltage diode such as a blu-ray or 445nm diode at these high currents. These diodes take like 5v or something. Amps * Volts = Watts. The Flexdrive can support 1.5A, but not 5*1.5A= 7.5 Watts. It's the power (watts) that the Flexdrive cannot support. The MicroBoost can support up to 1A with these high voltage diodes. It can support that 5 Watts (no personal experience, just what I've read!).

I believe (again, this is just my understanding from what I have read) that the diagram for putting two drivers in parallel would go like this:


I know that putting 2 batteries in parallel is basically just wiring their negative ends together, their positive ends together, and using the wire at each end to use the pair as one battery.

All of this is a lot to take in, and sometimes people need to have things explained in a variety of ways in order to understand it.

I'll let drlava tackle that drawing idea...

But about the output voltage. Yes, that is what the documentation states with the FlexDrive. However, there are a few who are still getting high current for blu-ray and 445 diodes using a FlexDrive. So even though it is not in the data sheet, it still seems to work! (although I personally have not done so, I use the Micro boostDrive for anything blu-ray or 445 build ('Hot' option kit) that is over 400mA's)

The drawing is correct. That is how two drivers are run in parallel. You would want to parallel the wires at some other point than the diode, presumably. I say this because it should be easier for you to 'Y' the wires closer to the driver, than to have 4 wire ends soldered at the diode. Electrically speaking, it will make little difference. It is just for cleaner physical layout. For the least amount of wire, the diode + from driver A could run to the diode + on driver B, and then 1 wire would run from that point to the diode +. Same thing for the negative side, and this could be used from the battery as well to minimize wire.

I wanted Tabish to read, because his question has come up before in this thread and results are there. The question of Flex vs Boost that is. While it may have been advised that a MicroBoost could be capable of higher throughput, in real-world use the Flexdrive has not demonstrated any lack of ability for the amperage I have seen discussed by anyone. Again, I have used the Flexdrive at ~1.2A @ 4.9V without issue. When these diode drivers are pushed above 1A, it would not hurt to adhere their bottoms to an aluminum sink with thermal epoxy.

Thanks for clearing it up. Microboost it is then.
I wish the website took paypal...

Tabish said:

Thanks for clearing it up. Microboost it is then.
I wish the website took paypal...

Click to expand...

PM drlava. He may work it out with you.

Peace,
dave

daguin said:

PM drlava. He may work it out with you.

Peace,
dave

Click to expand...

I've PM'd drlava about his drivers before. He is very helpful

Sent him a PM. Google checkout just isn't working for me for some reason....

The Shark Buck 2A adjustable driver arrived today. It is capable of 3A with a different resistor, but that shouldn't be needed.

Jay's copper module arrived today also. I am waiting for my diode removal tool to show up before I test the driver, because I do not want to push the 445nm diode that I have here without it being in that copper module. (It's in an Aixiz now.)

Here are some photos. One thing I like about this driver is the copper heat plate on the bottom.

Data sheet??

Looks interesting...

Is it supposed to handle 5 volts demand? Or is is designed for an LED emitter...