Odicforce Boost Driver?

[ZRaffleticket]

That is fantastic news. I know what I'll be using on the sharp 488s whenever they drop.

What is the min/max current these spit out?

 

[Astralist]

Great!!
The internal soft start really does its job.
I assume that your scopemeter is measuring voltage across sense resistor, is that right?

How about set the benchtop to 2.5A 3.7 volt? because those IC has a 2.5A typical switch current limit.

 

[jnrpop]

Hi Astralist,
It would be good to work with you on these tests as i'll do the same when your drivers arrive
So....
The soft start is working well.
My Scope is connected directly across the + & - output of the driver. This would be the most relevent point to test from??
I could set my P/S to 2.5A @ 3.7v, but the driver only pulls ~0.5A so it wouldn't change much??

Also one thing i dont understand, In order to get a very accurate mA reading on the DMM, the Testload Vf drop has to be correct, and at ~150mA the 1 Ohm resistor will only drop 0.15V, so its not so important,
but the Diodes are, is there a way to measure accuratley the Vf Drop of the Testload and not have to use the "Scale" or "graph" that we use for the IN5404 Diodes?

EDIT: Realised what i had asked above, I measured the Vf across the Diodes when running, it was 6.72V, so the Testload is set pretty close to the 6.6V the 505nm Diodes needs running @ 150mA......according to DTR's test video :beer:

 

[Astralist]

Hi

Pardon me, but i am quite confused about your scopemeter setup
Let's take this pic for example:

I believe 283.4mV are translated to mA.
But, the 2.436V as you said:

"My Scope is connected directly across the + & - output of the driver."

So that would means the voltage drop is 2.436V ???
To my understanding, if the voltage drop is about ~7V (including the resistor), then the + & - should reads ~7 too..
Also, what's with those half square wave with decay over time??

To measure current or produce Vf accurately, what i usually do is by using several combination of diode, in hope they produce right Vf at certain current, idk if anyone had a better method.

And one important things i wish that you are able to test:

1. Let say you set the current 150mA @ ~7V
2. Assuming the current is set, then please remove several diode so that the Vf reduced (let say remove 2 diodes so the Vf now are ~6V).
3. Does the current stays in 150mA?

 

[jnrpop]

Hi Astralist,
Thankyou for the reply as it great we can all work on this together,

So, the 283.4mW is indeed 283.4mA, this meter is connected across the 1 Ohm resisitor on my 3A TestLoad (10 selectable IN54004 diodes and 1Ohm resistor)

The 2.436V the Scopemeter is displaying if i am correct is the "Vout" from the driver minus the Vf drop from the Testload Circuit (Vf diodes + resistor)
This value can also fluctuate as the Diodes on the Testload heat up, so its not so relevant.

I believe i measured the True Vf of the Testload by putting my DMM across the Diodes and resistor when everything was running (Test on)??

EDIT: So i had a setting on my Scope not selected, the V displayed on the Scope was the Average V across the graph, i changed the setting to Max V, it displayed a Vf on 7.1V out from the driver, which is good news!

Also: I have two of these drivers, after the initual testing i did, i set the first driver to 180mA and have it running one of the original 505nm case neutral diodes. Its running fine after 10 or so 10 Sec on/off tests.......Positive news!!!

The second driver i have is still set up for testing.....but im going to sleep now

And the Wave pattern, the concave section, i believe its the capacitor draining out after the driver is cut from power?

 

[Astralist]

1. The 2.436V the Scopemeter is displaying if i am correct is the "Vout" from the driver minus the Vf drop from the Testload Circuit (Vf diodes + resistor)
2. I believe i measured the True Vf of the Testload by putting my DMM across the Diodes and resistor when everything was running (Test on)??
3. And the Wave pattern, the concave section, i believe its the capacitor draining out after the driver is cut from power?

Hi jnrpop, thanks for the answer..
here is my comment:

1. I think you might be mistaken, if what you are testing are true, then the 7V (Vf drop including resistor) + 2.436V equals 9.436V, which is above maximum output voltage of the driver which is 8V. CMIIW but those driver maximum output voltage seems fixed to 8V whatever the current is.
2. Your methods are correct, but regarding the point 1, "by putting my DMM across the Diodes and resistor when everything was running" is the same as "connecting directly across the + & - output of the driver." right? So where did you put the scope?? :thinking:
3. I see, now i understood about the graph

I hope you don't mind with these many question :beer:
And i think i might need to buy/build this driver myself just to confirm the logic behind its current control feedback :crackup:

EDIT:
Just saw your edit, that explains everything

 

[paul1598419]

I didn't even get a link in my email that this was going on here. I was planning on testing my driver today. I didn't read everything, but was wondering if these tests on the driver with the dummy load held current steady when fewer diodes were introduced in the load. I had the same concern as astralist when i traced the driver's set up that it might not actually regulate current, but regulate the Vf instead. This would be bad. I'll have to see what i come up with on my tests.

 

[Atomicrox]

IMHO you should place the scope between the 1ohm resistor's leads, that way you'll measure the current the diode sees.
I also noticed the scope is set to 1s/div, which is too much to accurately rule out spikes. You should verify the spikes across a much greater scale (us to s if possible).
Also the ripple doesn't seem that small. See if you can get a measurement on it.

Thanks for the tests, +rep!

 

[jnrpop]

I hope you don't mind with these many question :beer:

Not at all Astralist, more the better :beer:

but was wondering if these tests on the driver with the dummy load held current steady when fewer diodes were introduced in the load.

I'll also run a test using less and more Diodes and see what the current does

IMHO you should place the scope between the 1ohm resistor's leads, that way you'll measure the current the diode sees.
I also noticed the scope is set to 1s/div, which is too much to accurately rule out spikes. You should verify the spikes across a much greater scale (us to s if possible).
Also the ripple doesn't seem that small. See if you can get a measurement on it.
Thanks for the tests, +rep!

The scope's measuring the voltage spike atm across the output, but i'll run a test and put the scope in the circuit to see what the current looks like too

My Scopes lowest setting is 1s/Div on the Roll graph, but on previous tests measuring my Benchtop P/S on startup/shutdown, it recognised a very high spike in voltage using this 1s Division.......So don't attach your drivers or diodes to your Benchtop P/S and then turn it on but we all know this :beer:

What ripple can you see Atomicrox? which photo and ill check it out

 

[jnrpop]

So first, heres a nice graph of the IN5404 Diodes we use for the Testload, theres a difference in Vf drop from 0.1A to 1A (0.7 - 0.85V)

And Results from the Diode test on the first Driver:

Benchtop P/S set @ 3.7V
Testload: 10 Diodes down to 1 Diode using the bridging pins.

10. ? @ 8V
9. 149mA @ 6.96V
8. 182mA @ 6.3V
7. 227mA @ 5.64V
6. 292mA @ 5V
5. 389mA @ 4.36V
4. 535mA @ 3.78V
3. 941mA @ 3.45V
2. 1028mA @ 2.71V
1. 1066mA @ 1.92V

And the next test i did using driver 1, keeping the Benchtop p/s voltage @ 3.7V, and using selection 9 on my Testload
(9x IN5404 Diodes: 9x 0.7V = 6.3V + resistor drop of 0.150/1 = 0.15V so.....6.3+0.15 = 6.45Vf on the Testload)
I measured the min-max output of the driver by turning the Potentiometer:

3.7V In and a Vf drop of ~6.45V on the Testload (calculated)
Min: 140mA @ 6.8V (measured on meters)
Max: 410mA @ 7.4V (measured on meters)

So not the Min of 50mA @ 7.5V like the Spec sheet said :thinking:

 

[paul1598419]

What did you find for maximum current with the first driver? I noticed you stated the minimum current, but not max. I'll be testing mine today as I got jammed up yesterday and couldn't get to it. :thanks:

 

[jnrpop]

What did you find for maximum current with the first driver? I noticed you stated the minimum current, but not max. I'll be testing mine today as I got jammed up yesterday and couldn't get to it. :thanks:

Looking forward to your results Paul

520nm boost Driver No#1: Min= 150mA, Max= 400mA @ 6.5V
520nm boost Driver No#2: Min= 210mA, Max= 400mA @ 6.5V

450nm Boost Driver No#3: Min= 463mA, Max= 742mA @ ~4.8V

 

[paul1598419]

It will be later today, but i will get them done. Sorry, but i have other obligations. I have to deal with them first. :yh:

 

[ZRaffleticket]

That's quite a variance on the min... Crap, I had hoped to be able to gently ask a sharp 488 (when they come out) to push 5mW with one of these. Guess not.

 

[paul1598419]

Well, those Chinese drivers are not. The current changes as I add and subtract diodes in my dummy load. I set it at 200 mA with nine diodes in series. That increases to 290 mA with 5 diodes. The pot works, but it doesn't regulate current. It looks identical to the Odicforce ones too. I was going to go through it with my scope, but what's the point. I just put the scope away. I'm now concerned about all these drivers that look like it. Damn!

After looking at post #26, I don't believe any of these drivers regulate current. The Odicforce ones don't seem to either.

 

[jnrpop]

Well, those Chinese drivers are not. The current changes as I add and subtract diodes in my dummy load. I set it at 200 mA with nine diodes in series. That increases to 290 mA with 5 diodes. The pot works, but it doesn't regulate current. It looks identical to the Odicforce ones too. I was going to go through it with my scope, but what's the point. I just put the scope away. I'm now concerned about all these drivers that look like it. Damn!

After looking at post #26, I don't believe any of these drivers regulate current. The Odicforce ones don't seem to either.

I would imagine there the same drivers, and Odicforce are just re-selling from a chinese seller.

My results where the same, current reading across the 1 Ohm resistor changed as i took out 1 or added 1 diode on the TestLoad.

Thats the part i dont understand, with Current regulated drivers the mA reading shouldn't change? because on other drivers ive tested it was the same result, but i set the Testload to the Vf drop of the diode, adjusted the POT to the desired current and continued the build, never had a problem.....or so i remember :thinking: