OPEN SOURCE: "CC-Boost" - 2.4 Amp boost driver - RC1

[Alaskan]

I'd like a few of these too, if someone makes a batch please put me in line with the others. RHD, I have an old hand held O'scope that works, if you want it.

 

[rhd]

I played around with this driver at higher load voltages at max current (fixed version of the driver, set to a current above what I expected to actually hit) to test the limits of the input current, and I noticed that the board I was testing only pulled about 4A of input current, instead of 4.5 which is the theoretical max.

So it occurred to me that we might see some added efficiency by using an inductor with more of a saturation margin.

SRP1038A-220MCT-ND would be worth testing. 22uH, but higher saturation and lower resistance.

Also, I would be curious to try swapping the 26k resistor for a 21k, to push the OC limit a bit above spec.

 

[OSHStencils]

Ah yea it was, I was thinking of oshstencils. Eh, whatever. Also I think the link you were looking to post is this one: Free File Hosting - Online Storage; Upload Mp3, Videos, Music. Backup Files

Also, for the .08ohm Rsense, why not just use 2 .16ohm resistors. Finding a .17143 ohm resistor to go with the .15ohm seems a bit silly

Keep in mind OSH Park and OSH Stencils are not the same company. We do business together, but are different.

Given that our product is usually < $10, we have to charge for shipping as the margins are extremely low in order to keep the costs of the product low.

That said, we make $0 on shipping, it is completely pass through, and in some cases lose money on shipping (especially internationally). It's hard to get upset over $3-4 shipping internationally though Sorry to hear you felt like you got dinged, but that's what it costs us to ship there.

Keep up the great projects folks! We always appreciate seeing the stencils for all the cool laser drivers, and even built a couple ourselves!

-B

 

[crazyspaz]

I played around with this driver at higher load voltages at max current (fixed version of the driver, set to a current above what I expected to actually hit) to test the limits of the input current, and I noticed that the board I was testing only pulled about 4A of input current, instead of 4.5 which is the theoretical max.

So it occurred to me that we might see some added efficiency by using an inductor with more of a saturation margin.

SRP1038A-220MCT-ND would be worth testing. 22uH, but higher saturation and lower resistance.

Also, I would be curious to try swapping the 26k resistor for a 21k, to push the OC limit a bit above spec.

Maybe I will try some new inductors on my boards (not too hard to desolder), see if they still get so outlandishly hot. After all, it was the inductor that got hot, so maybe a little added efficiency will do it some good. BTW, have the drivers you have made had a high pitched whine? Mine all whine until basically spot on 1.5A and then stop. Kinda odd.

Has the ZXCT been ruled out as causing problems? I know it seems to heat up on mine, but I can't be sure if it is due to its proximity to the sense resistors.

Keep in mind OSH Park and OSH Stencils are not the same company. We do business together, but are different.

Given that our product is usually < $10, we have to charge for shipping as the margins are extremely low in order to keep the costs of the product low.

That said, we make $0 on shipping, it is completely pass through, and in some cases lose money on shipping (especially internationally). It's hard to get upset over $3-4 shipping internationally though Sorry to hear you felt like you got dinged, but that's what it costs us to ship there.

Keep up the great projects folks! We always appreciate seeing the stencils for all the cool laser drivers, and even built a couple ourselves!

-B

Right on

 

[The Lightning Stalker]

It is something to do with the way we are
testing them. There is no other reason why
the exact same driver would work in one
place, but not in another. It is either
our cells or the way we have them or the
test load and meter connected.

 

[crazyspaz]

It is something to do with the way we are
testing them. There is no other reason why
the exact same driver would work in one
place, but not in another. It is either
our cells or the way we have them or the
test load and meter connected.

My thoughts exactly. Only I tried 3 different meters, and my test load has worked flawlessly for other drivers. Parts didn't overheat when reflowing, no shorts...Its whatever at this point, I am pretty done with these drivers, at least this revision. Maybe I will try the EUP based board if it scopes clean.

 

[rhd]

Maybe this is a stupid question - I don't know - I don't follow boost drivers:

Which boost drivers don't require heatsinking at 2A ?

I'm confused as to where crazyspaz got this notion that you shouldn't have to heatsink a boost.... what am I missing? I came at this driver, and the OP, from the assumption that it was pretty cool and unique that a 2A+ boost driver could even go 30 seconds without heatsinking. But apparently, boosts never require heatsinking? (or at least that's the impression I'm getting from the complaints about having to heatsink this guy)

EDIT: fixed some types - I said "buck" above a couple times when I meant "boost"

 

[The Lightning Stalker]

My thoughts exactly. Only I tried 3 different meters, and my test load has worked flawlessly for other drivers. Parts didn't overheat when reflowing, no shorts...Its whatever at this point, I am pretty done with these drivers, at least this revision. Maybe I will try the EUP based board if it scopes clean.

Well, that still leaves open the wiring,
how it is connected and the cell(s)
itself. These demand more current than any
X-Boost, aside from the new SXB, and any
other handheld driver I have ever seen.
The wiring has to be short and the
connections must be very tight to minimize
resistance. The cell(s) must be able to
handle the current without sagging. A
multimeter will not show <1microsecond of
sag if it is present. There are so many
variables.

 

[Alaskan]

I'd like 3 each if you make some. If they can be turned down to as low as 200 ma I'd want to buy more.

 

[rhd]

I'd like 3 each if you make some. If they can be turned down to as low as 200 ma I'd want to buy more.

A heads up on the EUP boards - they are the first revision..... they might not work.

When I released CC-Boost, it was probably my 5th or 6th revision (maybe I said somewhere, but I forget). The EUP board is version 1. It might not work. Don't be shocked if it doesn't.

 

[IWIRE]

A heads up on the EUP boards - they are the first revision..... they might not work.

When I released CC-Boost, it was probably my 5th or 6th revision (maybe I said somewhere, but I forget). The EUP board is version 1. It might not work. Don't be shocked if it doesn't.

Thanks for the heads up. Looks like I'm back to working 7 days a week, probably be a minute before I have time to devote to assembling a drive.
I'm thankful I'm busy and my health allows it. :beer:

 

[crazyspaz]

Maybe this is a stupid question - I don't know - I don't follow boost drivers:

Which boost drivers don't require heatsinking at 2A ?

I'm confused as to where crazyspaz got this notion that you shouldn't have to heatsink a boost.... what am I missing? I came at this driver, and the OP, from the assumption that it was pretty cool and unique that a 2A+ boost driver could even go 30 seconds without heatsinking. But apparently, boosts never require heatsinking? (or at least that's the impression I'm getting from the complaints about having to heatsink this guy)

EDIT: fixed some types - I said "buck" above a couple times when I meant "boost"

The only boosts I have used at >2A dont need hestsinking, but those are lazeerers drives. And again, even if these do need hestsinking (which they obviously do), they should
a) not get so hot they can burn you after 10 seconds
b) not still get ludicrously hot when on a big hestsink (yes, I have tried) and
c) adjust to the correct current output. (All mine only do ~1.7A max)

I have been saying these things over and over again. I am not done with these drivers because I don't like the design, the concept, or you- I am done because I thought the whole idea of "open source" meant make some, play around with them, and report your findings. I have been trying to discuss these problems, but it seems no one really cares. Then, of course, the one I send you magically works when you get it. Not sure what I think about that, but it ticks me off for sure.

Again, nothing personal RHD- I just don't find it smart to continue to make these when I know the outcome. And that being said, I have already used one in a build- unfortunately, its the only laser I have with a driver limited run time (output eventually starts falling and eventually stops altogether).

 

[rhd]

I have been saying these things over and over again. I am not done with these drivers because I don't like the design, the concept, or you- I am done because I thought the whole idea of "open source" meant make some, play around with them, and report your findings. I have been trying to discuss these problems, but it seems no one really cares. Then, of course, the one I send you magically works when you get it. Not sure what I think about that, but it ticks me off for sure.

Me too

Frankly, I think drivers don't make sense to Open Source, and I think I was naive for thinking otherwise.

I was also naive, or perhaps just foolish, to make a driver type that I didn't myself use or like (boosts).

See, I didn't even realize the X-Boost didn't require heatsinking at 2.3A. The only note I read on that topic was a post on PL saying they DID require heatsinking. But looking at that again today, I realize that the author of that comment was TJ, so maybe I should have scrutinized a bit more.

Anyway, at this stage, I'm done with this driver too. Not because of your issues with it, just because it has done what I wanted it to do. It's a better option than the FlexDrive. Others can refine it, and frankly, if they don't, then so be it. If there isn't the drive (bad pun) to iterate an open driver, then the idea that this is a "community driver" was just a farce. It was "a driver that someone made and released the schematic to for free". That's much less interesting to me.

The problem, frankly, is that with the exception of 2 or 3 people, most users have viewed this project as their opportunity to get inexpensive boost drivers, rather than as their opportunity to work on a development project. "RC1" means "release candidate 1". That means it works, but it's still a work in progress. For people to use a "release candidate" three times, and then say "I'm done with this project" because it's not perfect, is illogical, and emphasizes that the project was approached with the wrong motivation from the outset.

If I had a suggestion for the future of this driver, it would be for someone to:
- Reduce the sense resistance to something that produces about 60mV of drop at 2.3A.
- Remove the pot and use a set resistor that will produce 2.3A.
- Change to an inductor with 22uH and sat current of at least 5.5A and is low a DCR as possible.
- By going 22uH, save enough space to shrink the footprint to something that fits inside a 12mm module, because I gather people care about that

But then again, with all that work, I think you'd be as well off to just swap ICs in the process (for the purpose of a higher frequency).

Anyway, I think I'm going to unsubscribe at this stage. The driver is out there. Nobody can complain about $30 flexdrives, anymore.

 

[The Lightning Stalker]

Well, hats off to rhd for putting this (and
others) out there in the first place. I
would REP again if I wasn't all REPped
out. There are always new things to learn,
even if you have been doing electronics for
over 20yrs as I have. We haven't heard the
last of the of the CC Boost™.

 

[crazyspaz]

Me too

Frankly, I think drivers don't make sense to Open Source, and I think I was naive for thinking otherwise.

I was also naive, or perhaps just foolish, to make a driver type that I didn't myself use or like (boosts).

See, I didn't even realize the X-Boost didn't require heatsinking at 2.3A. The only note I read on that topic was a post on PL saying they DID require heatsinking. But looking at that again today, I realize that the author of that comment was TJ, so maybe I should have scrutinized a bit more.

Anyway, at this stage, I'm done with this driver too. Not because of your issues with it, just because it has done what I wanted it to do. It's a better option than the FlexDrive. Others can refine it, and frankly, if they don't, then so be it. If there isn't the drive (bad pun) to iterate an open driver, then the idea that this is a "community driver" was just a farce. It was "a driver that someone made and released the schematic to for free". That's much less interesting to me.

The problem, frankly, is that with the exception of 2 or 3 people, most users have viewed this project as their opportunity to get inexpensive boost drivers, rather than as their opportunity to work on a development project. "RC1" means "release candidate 1". That means it works, but it's still a work in progress. For people to use a "release candidate" three times, and then say "I'm done with this project" because it's not perfect, is illogical, and emphasizes that the project was approached with the wrong motivation from the outset.

If I had a suggestion for the future of this driver, it would be for someone to:
- Reduce the sense resistance to something that produces about 60mV of drop at 2.3A.
- Remove the pot and use a set resistor that will produce 2.3A.
- Change to an inductor with 22uH and sat current of at least 5.5A and is low a DCR as possible.
- By going 22uH, save enough space to shrink the footprint to something that fits inside a 12mm module, because I gather people care about that

But then again, with all that work, I think you'd be as well off to just swap ICs in the process (for the purpose of a higher frequency).

Anyway, I think I'm going to unsubscribe at this stage. The driver is out there. Nobody can complain about $30 flexdrives, anymore.

I agree completely. But, and I have said this before, there really is nothing I can contribute to the development other than report and problems I find. If that came across as me saying "wahh I want cheap drivers," then so be it, I suppose. Certainly not my intent. The only reason I made so many is because it was cheaper (so may as well) and it had been reported as working. My end goal was to sell them for a few $ over part cost, and donate all the money made (not just the bit of profit) to you...obviously not going to happen at this point.

All in all it was a novel concept, and I am not convinced it can't be refined even more. But, like you have said, there is just not enough of the community who actually cares about something like this. I am sure at one point there was, but that group has long since been overtaken by the "duhh I want burning lazor" kinda people.

In the end, I suppose I am content- I got an introduction on reflowing (and would say I'm moderately proficient at it), and got to learn more about simple circuits like this. Now maybe I can take a crack at that tiny linear drive I talked to you about

 

[jayhawker08]

Finally received the last of the components yesterday and put together a board. Output seems fine when checking with a multimeter, but further inspection with a scope shows a lot of oscillation. This occurs both when powered via battery (18650 panny) or power supply (voltage set at 4.1V, no current limiting). Voltage across a 0.1 ohm resistor was scoped. Dummy load was set to drop ~4V. IC and inductor get warm after ~30 seconds, but nothing unusual. Can easily hold finger on them. Occasionally it will be steady for a few seconds and then start oscillating (while emitting a high-pitch tone). Any suggestions?

Scope pics can be seen here: https://imgur.com/a/pZDuo