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2 Drivers to the Same Diode?

daguin

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Hemlock Mike sent me a couple of cool switches
sku_5604_3.jpg


With this switch, I can switch between two different power poles. They would have a common negative.

The question is, can I power two different MicroBoost drivers attached to the same diode?

The drivers would be powered separately and never be both powered at once.
Could I set up a low power driver and a high powered driver to the same diode if they would never be energized at the same time?
Would the power running into the un-energized driver from the output side cause a problem?
Would it energize the second driver?

Peace,
dave
 





drlava

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You can run two drivers separately IF you switch off the V- on the unused driver. But why use two drivers and not switch something else, say a range jumper to get two powers?
 

Morgan

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Are these mini latching switches or rotary? I can't tell from the diagram but that may be me just not understanding. Sorry, I can't read the Chinese!

M
:)
 
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They appear to be the same switches I have here, which are ratcheting clicky switches (off, on, on)

High current buggers too...
 

daguin

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You can run two drivers separately IF you switch off the V- on the unused driver. But why use two drivers and not switch something else, say a range jumper to get two powers?

Mainly because I cannot envision how I would do that :yabbem:

So if I run the host case-positive and switch the negative leg it will work?



Are these mini latching switches or rotary? I can't tell from the diagram but that may be me just not understanding. Sorry, I can't read the Chinese!

M
:)


I haven't torn one open, but it sounds like a rotary.

They appear to be the same switches I have here, which are ratcheting clicky switches (off, on, on)

High current buggers too...

It is clicky: off -- on leg 1 -- off -- on leg 2

Peace,
dave
 
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Interesting idea... I actually was thinking of something like this for my 445 the other day. You get the best of both worlds, wavelength and power...

Although I was thinking of some sort of circuitry to do the trick, not just a SPDT switch...
 
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Mainly because I cannot envision how I would do that :yabbem:

So if I run the host case-positive and switch the negative leg it will work?






I haven't torn one open, but it sounds like a rotary.



It is clicky: off -- on leg 1 -- off -- on leg 2

Peace,
dave

Correct me if I am wrong, but I believe Drlava is meaning to use a switch wired to the necessary connections on a flex drive for example that would set a given output range. Instead of permanently soldering a range have a switch wired between two ranges.

So simple, great suggestion Drlava I'm surprised I hadn't thought of that before.
 
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Morgan

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^That would mean choosing a happy medium from the two ranges you chose. Good compromise using one driver though. It assumes a fixed point on the pot will give you the desired output in the low range and an acceptable one in the high but it's not like these diodes are going to be strained in any way and a damned simple solution!

I get the operation of the switch now. Not what I thought initially. One click - one path; another click - another path; one more click - OFF! Thanks Dave.

M
:)
 

daguin

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^That would mean choosing a happy medium from the two ranges you chose. Good compromise using one driver though. It assumes a fixed point on the pot will give you the desired output in the low range and an acceptable one in the high but it's not like these diodes are going to be strained in any way and a damned simple solution!

I get the operation of the switch now. Not what I thought initially. One click - one path; another click - another path; one more click - OFF! Thanks Dave.

M
:)

Starting - off
One click - one path;
Another click - off;
Another click - the other path;

Peace,
dave
 

Morgan

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^ Perfect! Thanks...

Always clicks to an OFF, from wherever it's ON!

Totally gotit! :beer:

Very cool switches! GB :anyone: ? :crackup:

[EDIT: I just noticed that 445nm is only mentioned once in this thread. I must have them on the brain. I'm sorry... :eek: Other diodes may well be affected by the ranges you choose.)

M
:)
 
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daguin

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I want very low power for lining up experiments and then very high power for the actual run. Two drivers still look like the way to go.

Peace,
dave
 
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Is this for a portable application? I ask because you can always use a pot, or some range resistors with the LM317 or other higher current regulator. I can help you determine what values to use if needed..

Two drivers and any 3 way switch could easily do the trick also..
 

daguin

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Is this for a portable application? I ask because you can always use a pot, or some range resistors with the LM317 or other higher current regulator. I can help you determine what values to use if needed..

Two drivers and any 3 way switch could easily do the trick also..


Yeah. It's going into a Pontiac prototype host. Got the 18500 battery I needed today. Now I've got to figure out how to set up the electronics.

Peace,
dave
 
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Hmm, that host wouldn't have any room to mount the tab from a sliding 3 way switch would it? If this tiny push button switch of yours doesn't seem to do what you intended, a sliding switch would be the next best thing.

How would you prevent the driver- caps from zapping the diode every time you switch to the other driver? The driver that gets switched off, would need to have its output terminals shorted each time it is shut off!

For simplicity's sake, a switch to change jumper positions on a flex drive is the best idea here IMO.
 
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There are a couple of ways to do it with the sense resistors: use a shunt for the sense resistor and a simple SPST switch to active the shunt path, or use your switch and have 2 different sense resistance values, one on each path of the switch.

Not as familiar with the Microboost, but the LM317 as an example:

Using a shunt path: Set the sense resistor for low power, say 225mA for the 445nm Casio, that's ~3.73ohms sense resistance. Now, have a shunt resistance in parallel to that resistance with a switch to active that path. So for 1A current, you need 1.25ohms sense resistance, so you need to activate a path that is parallel to your 3.7ohm resistor that has a resistance of 1.88ohms. Just by closing the switch, you change the sense resistance from 3.73 to 1.25 ohms, changing the current from 225mA to 1A.

Using the switches 2 paths as 2 separate resistances should be pretty self-explanatory though, I think. Just wire the 2 paths in parallel, each with the desired resistance, and you can choose which path you want based on desired current. I like the shunt resistance better since it doesn't ever break the circuit.

-------------------------

ETA: Ah! But I do see the appeal of this, that it'll be your ONLY switch. You're not wanting a second switch, you're wanting one switch total. Yeah, 2 drivers may be doable, but not the most elegant? Not familiar enough with the Microboost to really think through the elegant solutions. Good luck, post back what you decide.
 
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Toke

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Have you considered a flashlight driver with multiple modes?
It might be a problem finding one with the right current ranges, but they do come with several modes, including strobe. :D
 




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