Butterfly external power

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I have 3 AA batteries which gives about 4.1 volts so it is within the specs. Should I remove the button cell battery when using external power? I am a computer nerd not an electronics nerd so I'm wondering if the amps matter. The specs just tell you about volts, but wouldn't there also be some kind of range for the amps? It would seem that 10000A would kill it. :P

Also, what is a good way to connect everything to the butterfly? I have a two row header, but the electronics store didn't cary any two wire connectors. :roll: Any way to hook it up to a breadboard?

Pardon my noob. :oops: :P

Math is cool.
jevinskie.com

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We're all noobs somewhere :)

I'm *guessing* you should remove the coin cell. Unless it is diode protected (I doubt it is), putting other batteries on there that have a higer voltage will try to charge the coin cell - bad form.

10,000A will kill a lot fo things :)

There is a thing called Ohm's law that comes into play. If you can treat the butterfly as just a resistor (not too bad an approximation) then the current it draws will be determined by the voltage you apply to it - not how much your power supply (batteries, Hoover Dam, etc) can deliver.

I think that's what you meant - would using a higher voltage power supply draw higher current? Generally that is true.

If you have the header stock, a quick way of hooking up if you don't have the actual connector is to use wire-wrap wire. Header posts take to wire wrap wire like the were made for it - and they basically were. It isn't permanent but gives a really good connection that you can just pull off when you are done. You can get a cheap but very servicable wire wrap tool at Radio Shack or similar.

Please note - this post may not present all information available on a subject.

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The Butterfly coin cell is diode-protected. There is no need to remove it.

If you need your own copy of the schematic, check the Atmel web site.

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refields wrote:
We're all noobs somewhere :)

I'm *guessing* you should remove the coin cell. Unless it is diode protected (I doubt it is), putting other batteries on there that have a higer voltage will try to charge the coin cell - bad form.

10,000A will kill a lot fo things :)

There is a thing called Ohm's law that comes into play. If you can treat the butterfly as just a resistor (not too bad an approximation) then the current it draws will be determined by the voltage you apply to it - not how much your power supply (batteries, Hoover Dam, etc) can deliver.

I think that's what you meant - would using a higher voltage power supply draw higher current? Generally that is true.

If you have the header stock, a quick way of hooking up if you don't have the actual connector is to use wire-wrap wire. Header posts take to wire wrap wire like the were made for it - and they basically were. It isn't permanent but gives a really good connection that you can just pull off when you are done. You can get a cheap but very servicable wire wrap tool at Radio Shack or similar.

Heh, thanks!
I now understand the current draw. :D

When I said header, I ment header pins. I'm sorry that I didn't know how descriptive to be or any better terminology. :P

Up until now I didn't know that wire wrap sockets even existed! I'll see if the local Radio Shack has them or header socket thingys. :D Any ideas on what to do in the mean tiime? I don't really want to solder something on and then have to remove it. Ugh, I hate soldering with a passion! :(

Math is cool.
jevinskie.com

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Mike - I do have the schematics - but not here where I wrote the reply. Mellow, man. Mellow. I covered the bases and mentioned the diode protect possibility. I just didn't remember if it had one or not. I pop in occasionally to see what's up but really can't spend the time doing legwork that others ought to do for themselves.

And Jevin, about the header pins. I was actually referring to header pins and not sockets. Wire wrap wire will wrap right around them. But there are wire wrap sockets too. If those work and solve your problem, great! More power to you! (literally ;)

Please note - this post may not present all information available on a subject.

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Hi,

refields wrote:

Quote:
Mellow, man. Mellow.

I didn't get the feel he was lambasting you or anything, just reporting the facts.

Regards,
Steve

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All is mellow here; I was making sure that Jevin knows where to find the schematic.

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If you have any junk cables from a computer motherboard, like disk drive cables or serial port cables, the spacing should be the same (0.1"" square), and the ribbon cable is already connected to one end.
--
john