Damir's stereo shutter release PCB modifications?

Anaglyphic

129
Anaglyphic lives!

« on: 26 / February / 2008, 10:51:57 »

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Hey guys.

OK so this is regarding the continuous w/ synchronized flash circuit linked by Microfunguy and others that is supposedly designed by Dr. Damir Vran?i? (of 3D LanC Master fame)...

Anyway, it could really use a switching boost converter circuit on-board, since some people have had trouble triggering certain cameras with ~3V. But also, this would then allow the circuit to provide +5V from a single AA/AAA NiMH cell, as 3V lithiums are expensive and single-use.

There are of course many ways this could be implemented, even linear vs. switching as it's a low-current application, so what's the criteria? Cost? Ease of use (eg. avoid humans soldering SMTs and cussing)? Lowest external component count? Etc.

I am an amateur engineer at best, and a bloody hack who messes everything up at my worst.

So, is there someone better qualified I should send my suggestion to, or a more appropriate place to voice this?

Thanks.

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Pauls9

60
S3 IS

Re: Damir's stereo shutter release PCB modifications?

« Reply #1 on: 26 / February / 2008, 12:05:33 »

Given that the current required is small (or so I understand), it might be easier to use more cells and a linear regulator.

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Anaglyphic

129
Anaglyphic lives!

Re: Damir's stereo shutter release PCB modifications?

« Reply #2 on: 26 / February / 2008, 16:00:37 »

No, more cells is not an option. If you are willing to carry them, then etch the board as-is.

We're already carrying two cameras and two supplies; the fact we can't tap the camera's battery is embarrassing enough, but most don't want to make any permanent camera mods. So the grip needs to be as light as possible, and the charge doesn't need to last any longer than your Canon battery pack or your pair/quad of AA NiMHs.

ACTUALLY, I would go so far as to make a centralized power supply, feeding both cameras via their DC In ports. (since we have to leave the port covers open anyway for the USB)... one set of batteries vs. two... perhaps less runtime but in the end, yet since most Canons battery doors are blocked by being mounted, it would be easier to change cells than dismounting both cameras from the bracket.

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Since we cannot know all that there is to be known about anything,
we ought to know a little about everything. -- Blaise Pascal

crunchy_3d

25

Re: Damir's stereo shutter release PCB modifications?

« Reply #3 on: 29 / February / 2008, 06:17:38 »

Quote from: Anaglyphic on 26 / February / 2008, 10:51:57

Anyway, it could really use a switching boost converter circuit on-board, since some people have had trouble triggering certain cameras with ~3V. But also, this would then allow the circuit to provide +5V from a single AA/AAA NiMH cell, as 3V lithiums are expensive and single-use.

There are of course many ways this could be implemented, even linear vs. switching as it's a low-current application, so what's the criteria? Cost? Ease of use (eg. avoid humans soldering SMTs and cussing)? Lowest external component count? Etc.

I am an amateur engineer at best, and a bloody hack who messes everything up at my worst.
So, is there someone better qualified I should send my suggestion to, or a more appropriate place to voice this?

Unfortunately, switching "boosters" require quite some current in initial phase until the nominal output voltage is reached. They also require some constant current for functioning. So, we should have additional "power" switch (did you ever forget to switch off some devices?). If it would work at all (inner resistance of a cell battery is relatively high for initial consumption of the switcher), the cell battery would be flat very soon. Believe me.

Better solution, which I would probably use, is to use single AA or 1/2 size of AA Lithium 3.6V battery or 6V battery with two diodes in series.

The motivation in circuit design was to make the circuit as simple as possible and as small as possible.

Damir

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crunchy_3d

25

Re: Damir's stereo shutter release PCB modifications?

« Reply #4 on: 29 / February / 2008, 07:40:03 »

The following batteries could be useful:

http://tinyurl.com/3bvp8p

Otherwise check at Farnell.

« Last Edit: 29 / February / 2008, 07:42:41 by crunchy_3d »

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