anyone can help or know how?

[ndrew2505]

got my sonar case and hs today(thanks murudai and DH ) but i was wondering if any1 has found a way to drop the voltage down on the rechargeable rcr123's to make ~5v? i tried playing around with some resistors last night and today but didnt find much out in the way of a solution. thanks for any help or input in advance.

 

[pullbangdead]

You can use diodes, 1N4001 or whatever number (they're all about the same for what you want). ~.7V drop apiece, put them in series.

Not overly efficient, but it'll do in a pinch.

 

[laserguys]

Depending on the current required, you could use a 5 Volt LDO regulator.

 

[ndrew2505]

Depending on the current required, you could use a 5 Volt LDO regulator.

dont those things get hot tho? i was searching around on google and i found this at digi-key:

http://www.cui.com/pdffiles/V78XX-500 Series.pdf

from what i can tell the specs look ok but im no expert either. what do you guys think?

 

[rog8811]

I have used the small transistor size 7805 for PS3 blu rays, they work well up to 100ma which I belive is the max output..... the one you link to seems fine as it goes up to 500ma, I would assume that as you are only dropping a couple of volts they would run quite cool.

Regards rog8811

 

[Bionic-Badger]

Just grab some of those 1N4004 rectifier diodes mentioned above from Mouser. They're cheap (500 for $8), and you can use them in your other drivers too. Each drops about 0.6-0.7V, and since they're so cheap you can just put multiple diodes in series if you need more drop, especially for future builds. The wire they use is relatively stiff so you can use it to attach to a spring for the batteries. Hell, if you need some I can ship you some for cheap or something.