Contest (feeler): 2-months, to design a NEW community boost driver!

[Wolfman29]

Hey, you're telling me. All my heatsinks are made on a HANDdrill.

 

[steviedezie]

props to you man...us lathe-less folks gotta make due with what we got right??? hahaha

 

[Wolfman29]

Yup! A hand drill, some sand paper, and a couple of files... but we stick together!

 

[random person]

so far my single cell lpc-826 build is using this driver here:

$2.19 - 1.5V~4.2V 3W Cree Circuit Board for Flashlights (16.7mm*5.6mm) - Flashlight Parts and Tools

Its a boost driver, so i soldered 2 1n4001 diodes in series with the output and it boosts up the voltage fine, im using a 14500 cell and the current to the diode is 515...which i think is perfect for long life with a lpc-826 diode.

how would you regulate the current output of that? Put a pot in series with the laser I assume? Hmm... so why don't people just use this instead of the flex drive? It does boost and it would seem to do the job. No point in building a boost driver if there is already one out there thats a good replacement of the flex drive. I can't compete with a 2 dollar price tag.

 

[Helios]

how would you regulate the current output of that? Put a pot in series with the laser I assume? Hmm... so why don't people just use this instead of the flex drive? It does boost and it would seem to do the job. No point in building a boost driver if there is already one out there thats a good replacement of the flex drive. I can't compete with a 2 dollar price tag.

Well I dont think it has a POT so its going to be a bit harder to set and there hasnt been any research into its output stability so its hard to say its a direct replacement. However it does seem quite promising.


EDIT: It also doesnt look like it will work for 12X builds

 

[random person]

Well I dont think it has a POT so you its going to be a bit harder to set and there hasnt been any research into its output stability so its hard to say its a direct replacement. However it does seem quite promising.


EDIT: It also doesnt look like it will work for 12X builds

Sorry, still new to the laser community, why wouldn't it work? 12X builds have a higher voltage drop then 4.2V or what is the issue?

 

[Wolfman29]

Yes - 12x builds can have Vfs of upwards of 6V. I have used that driver before, it doesn't boost high enough for 12x, and barely high enough for 445nms.

 

[steviedezie]

in the newest batch of these drivers that I have recieved...it only boosts to about 5.1V or so.

this is a fixed output driver...it is constant current regulated at 600mA stock...now I've had a fair degree of success changing the resistors to lower the output to 515mA and to increase it to about 700mA...but thats about it.

but in most builds, a fixed output is all thats required. It is by no means a replacement for the flexdrive or the microboost drives, but it works fine in certain scenarios and is a very reliable fixed current boost driver. But seeing as the current limit is quite low, I would say this would only work to make low powered 445's and red builds (with smd diodes in series to the output)

 

[random person]

Yes - 12x builds can have Vfs of upwards of 6V. I have used that driver before, it doesn't boost high enough for 12x, and barely high enough for 445nms.

Then how would a flex drive work with that? Flex drive manual says only from 2-5.5V volts?

Currently working on producing a boost/buck driver.

Input voltage from 1.5V to 5.5V. Max current output 3A.
Output voltage 1.2V to 5.5V.
95% efficiency
Is it worth producing?

Or I could make....

Input voltage from 2.7V to 14V
Output from 2.5V to 15V.
2.5A.

Issue with the later is it wouldn't allow the use of a single AA, AAA ...ect

I could also make a general purpose one that would take 1.2V to 30V as a buck/boost drive but that would require 2 different driver ICs based on the voltage range and thus would be more expensive and bigger. Not sure if anyone would be a fan of that.

 

[bluuray]

the flex wont work with 12x's ( that i know of)
only a microboost will work.

 

[random person]

the flex wont work with 12x's ( that i know of)
only a microboost will work.

Oo nice, so i'll out beat the flex drive if I can make a 18650 full power a 12X?

I think i'll go for the 2.7V to 14V IC then. Will require a 3.6V Lithium ion min to run. Would that be a major issue? Do people here fancy batteries of lower voltage then that?

 

[Kevlar]

I believe most here use Li Ions anyway. I do mostly because the hosts I like are usually 16340 or 18650 size.

 

[rhd]

Why you would need to boost to 14V is beyond me...?

Also, I'm fairly sure that a Flexdrive WILL work for a 12x, no?

 

[Kevlar]

I think a flex will work with a 12X. You just wont be able to drive it to the max.

 

[bluuray]

Why you would need to boost to 14V is beyond me...?

Also, I'm fairly sure that a Flexdrive WILL work for a 12x, no?

the IC can boost up to 14v.
so it could work for both 445nm and 405nm

 

[Helios]

Oo nice, so i'll out beat the flex drive if I can make a 18650 full power a 12X?

I think i'll go for the 2.7V to 14V IC then. Will require a 3.6V Lithium ion min to run. Would that be a major issue? Do people here fancy batteries of lower voltage then that?

Most builds here run on li ions.