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FrozenGate by Avery

FREE DIY open source BOOST driver!!! Tested & working!!

I decided to torture the dual-boost SAIK build to see how it behaved under a long run time. Despite the skepticism from Johnnyz, these drivers appear to like being paralleled.

EDIT
Okay, here are the results. Here's what you're looking at:
- Dual boost driver SAIK build, with each set for 864mA.
- In practice, with the paralleled setup, there was 1.66 A to the diode.
- Powered by a single 26650.
- Aixiz 3-element lens (NOT a G1 as I had used in post #2)

What You're Seeing:
- On the right hand side, the first "kink" or "decline" is where the drivers went into rapid "pulse" mode.
- The second "kink" or "decline" is simply me shutting it off.
- It ran for about 7 minutes before the drivers decided enough was enough.
- I have observed two driver behaviors when it is "tired". It will either pulse rapidly, or simply dim the LD (ie, lower it's current). I do not yet know which behavior is caused by heat (thermal protection) vs insufficient battery current supply to continue boosting to the set current. I presume that each behavior is attributable to one of these two issues.

All in all, this is pretty impressive performance.

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So is the mosfet labeled wrong?

Not that it really matters with the PCB, as we can just flip it around, but it would be good to know :D
 
rhd: I had two drivers set at 1A, 10uF input cap, 10uF schottky cap, 22uF output cap, 10uH coil, hand soldered. After paralleling them and powering them with a lab PSU and hooking up a 3A heatsinked test load, I was only getting around 600mA.

Other than that, I too find that "rapid pulse mode" the driver does when overloaded (battery too low, driver too hot) pretty amusing. It is not in the datasheet, is it? I might just publish my designs too.
 
Mohrenberg said:
So is the mosfet labeled wrong?

Not that it really matters with the PCB, as we can just flip it around, but it would be good to know :D
Click to expand...

Looking at the PCB layout you can't just flip it around
if it was required...:yh:

rhd said:
I think the conclusion was no - wasn't it?
Click to expand...

Up to this point the Q1 connections seem to function
by the link description I read yesterday...
I spent about an hour this morning researching on the
web and the way Q1 is hooked up for reverse polarirty
protection on the PCB should work just fine..

@RHD... were your tests with the most recent graphs
performed with both drivers using the Q1 Reverse Polarity
protection on the Driver...:thinking:


Jerry

You can contact us at any time on our Website: J.BAUER Electronics
 
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I'm nearly 100% sure that it is correct, but I haven't tested that setup and I don't have any p-channel mosfets lying around to test it.

Johnyz said:
rhd: I had two drivers set at 1A, 10uF input cap, 10uF schottky cap, 22uF output cap, 10uH coil, hand soldered. After paralleling them and powering them with a lab PSU and hooking up a 3A heatsinked test load, I was only getting around 600mA.

Other than that, I too find that "rapid pulse mode" the driver does when overloaded (battery too low, driver too hot) pretty amusing. It is not in the datasheet, is it? I might just publish my designs too.
Click to expand...

Did you actually measure the voltage across your test load or just estimate by the number of diodes? You could have been boosting to well over five volts and that caused a decline in output current.
 
Mohrenberg said:
So is the mosfet labeled wrong?

Not that it really matters with the PCB, as we can just flip it around, but it would be good to know :D
Click to expand...

I've read the whole thread a couple of times and my take is the same as rhd's.

Jerry questioned it, Ben sent Jerry a link that explained how he was using it in the circuit and Jerry replied that "Thanks! He learned something new!"

So the final verdict was that the circuit board is correct as printed.

Wolf man is claiming to have a circular design with all the components on one side and battery connector on the other side, but I don't know if that is something that he intends to share or just make himself or sell or what...

That is the summary so far.

:)

Signed, your fan
 
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Johnyz said:
rhd: I had two drivers set at 1A, 10uF input cap, 10uF schottky cap, 22uF output cap, 10uH coil, hand soldered. After paralleling them and powering them with a lab PSU and hooking up a 3A heatsinked test load, I was only getting around 600mA.

Other than that, I too find that "rapid pulse mode" the driver does when overloaded (battery too low, driver too hot) pretty amusing. It is not in the datasheet, is it? I might just publish my designs too.
Click to expand...

Interesting - I'm not sure how to explain that. I know that I initially had trouble paralleling from my bench PSU as a power source when I slowly ramped up the input current, as opposed to just turning it on. Even still, it worked, but there was some strange behaviour when I approached it that way. It may be that during the "struggle" period as current is ramped from a bench PSU, the drivers get into some sort of weirdo mode that they can't just pop out of. Whereas with a cell supply (or a PSU that is just turned out) they somehow don't meander down that rabbit hole and get all confused. That's about the least scientific explanation I've ever posed, for something that must have a scientific answer ;)

Quite seriously, I actually *love* the rapid pulse low-current/high heat mode. I almost considered setting a driver way too high, and doing a build, just for the amusement of it. It's like a very fast strobe mode. I have one C3 build that I tested with the current set at 1.2A and the driver un-heatsinked. I can get about 1 minute of run-time before I hit strobe mode. It's a neat balance. I'd like to hook a build up to a scope and see what is happening during this strobe.

On another note, I heatsinked the driver in a build last night, set for 1.4A. It's alright - it can handle it - for about 2 minutes before hitting strobe mode. 1650mW output through a 3E lens.

lasersbee said:
Looking at the PCB layout you can't just flip it around
if it was required...:yh:

@RHD... were your tests with the most recent graphs
performed with both drivers using the Q1 Reverse Polarity
protection on the Driver...:thinking:

Jerry
Click to expand...

No they weren't. I don't have that PCB yet (though I've ordered 60). Dorkbot takes quite a while to get boards out to me here in Canada.

Side-note, do you know of any PCB fab options here in Canada that might not be too pricey, and might be appropriate for an order of under 100 square inches? I don't know how many SQ inches a typical board is, but it might not be totally out of the realm of possibility that I could grab one on my own.
 
1.4A! I never thought you would get that high ;)

Have you tested that current over the discharge of a battery (or simulated it with a bench psu)? It would be interesting to see what voltage it can no longer hold that up at.

If you wanted, you could probably recreate that pulse mode if you made a little 555 timer board and connected the output to the enable pin. Just leave off the 100k resistor.
 
Very cool. Thank you for sharing your design and letting everyone benefit from your hard work and research. Quick question guys, will this driver accept a PWM signal?

Thanks

J
 
rhd said:
No they weren't. I don't have that PCB yet (though I've ordered 60). Dorkbot takes quite a while to get boards out to me here in Canada.

Side-note, do you know of any PCB fab options here in Canada that might not be too pricey, and might be appropriate for an order of under 100 square inches? I don't know how many SQ inches a typical board is, but it might not be totally out of the realm of possibility that I could grab one on my own.
Click to expand...

When I have small quantity prototype PCBs to make I use
APCircuits in Alberta...

APCircuits


Jerry

You can contact us at any time on our Website: J.BAUER Electronics
 
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Jubathoph: Yes, these can handle PWM signal if you feed it to the DIM/EN pin of the IC.

When I was considering making SimpleDrives (seems like ages ago :) ) I talked to a company that makes aluminum double side PCBs - seemed like a nice touch. You know - better heat transfer, more temperatureproof (it doesn't seem like, but anyone that handled LM3410s knows that these guys like it HOT!, and the FR4 PCB *might* degrade over time.) and white PCB looks just plain awesome.
 
Johnyz said:
Jubathoph: Yes, these can handle PWM signal if you feed it to the DIM/EN pin of the IC.

When I was considering making SimpleDrives (seems like ages ago :) ) I talked to a company that makes aluminum double side PCBs - seemed like a nice touch. You know - better heat transfer, more temperatureproof (it doesn't seem like, but anyone that handled LM3410s knows that these guys like it HOT!, and the FR4 PCB *might* degrade over time.) and white PCB looks just plain awesome.
Click to expand...

Have fun soldering to aluminum though. :P
 
benmwv said:
1.4A! I never thought you would get that high ;)

Have you tested that current over the discharge of a battery (or simulated it with a bench psu)? It would be interesting to see what voltage it can no longer hold that up at.

If you wanted, you could probably recreate that pulse mode if you made a little 555 timer board and connected the output to the enable pin. Just leave off the 100k resistor.
Click to expand...

Le Quack said:
Have fun soldering to aluminum though. :P
Click to expand...

LOL, I'm sure the aluminum is covered in a layer of copper.
 
Johnyz said:
Jubathoph: Yes, these can handle PWM signal if you feed it to the DIM/EN pin of the IC.

Sweet. Anyone know why we don't see a lot of pointers using PWM to control brightness? Seems like it would be very useful especially on the beastly 2000mw 445 builds...sometimes it would be nice to quickly lower power in order to facilitate focusing or even just to prolong runtime when full power is not desired.
Click to expand...
 
rhd: yep, aluminum is used as a core instead of FR4
Jubathoph: Let me dig up something I designed a little while ago... There we go.

3D render of front side
3D render of back side

Eagle BRD and SCH
pld-01.brd
pld-01.sch
This little thingy even has a transistor inside to be used with drivers that don't have modulation inputs. Intended for linears, I have absolutely no idea of slapping it before a switched mode. It is still possible to grab the PWM output out of the 555 and wire it directly to the EN pin. That little kink can be filed off, I just put it there to make it comply with the PCB fab design rules.
 
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