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Re: Digital Power Supplies.

Posted: Fri Dec 10, 2010 4:36 am
by Jero
keep these ideas a flowin' fella's

Re: Digital Power Supplies.

Posted: Fri Dec 10, 2010 12:20 pm
by McSpunckle
multi_s wrote:
McSpunckle wrote:I'm working on and off on rechargeable pedals unsing lithium ion battery packs... haven't been able to figure out how to switch the charger. And all the 9V equivs are actually 7.4 volts... so it'd need a different sorta battery pack. Different battery pack would get a lot more juice out of a charge, though! (like, the equivalent of SEVERAL batteries).

It'd be easy to wire it up like a normal battery, and add a charge switch... hmmmz

Digital power supplies don't make sense to me, other than being more efficient (thus able to put out more power-- that Godlyke puts out twice what a 1-spot can).


this is something i have thought on as well. I think batteries are a real waste. embedding rechargables that are automatically recharge when your adapter is handy would be amazing. You could do it with a small MCU and the normal DC jack that picks battery or adapter depending on whats plugged in. You can have the same MCU manage a boost converter to get that 7.4 to 9v. Basically you need a small mcu a rechargeable cell and an inductor.

if you went tqfp you could probably fit it on a very small board.


I'm totally down with SMD. Drag soldering is kinda fun!

Got any info on this? All I have is the schematics and battery packs from Sparkfun. D:

Re: Digital Power Supplies.

Posted: Fri Dec 10, 2010 1:20 pm
by dune2k
Why not use 12V rechargable battery and a 78L09 to bring it down to stabilized ~9V? (Or just use the 12V rechargable batteries.)

Re: Digital Power Supplies.

Posted: Sat Dec 11, 2010 9:38 pm
by multi_s
why not just design pedals to run off 1.2/2.4 v and use AA rechargeable, or a solar cell, or a transducer that will recover the energy from the vibrations of your amp. :P

i guess i was thinking something more universal.For example if your pedal is already sized to fit a 9v cell and already designed to run off 9v, you could put the rechargeable cell and a small pcb in the same space. If your designing the whole pedal from scratch obviously you have a lot more liberty.

linear regulators work but they are really not efficient. But your idea may be useful too. To me if your designing something like this, battery life would be a main concern and you would want a more efficient regulator.

@mcspunkle

i just moved but maybe we could proto something even as an experiment soon.

edit: also do you have rechargale 9v cells? are you sure the only put out 7.4 v? im going to but some on ebay and see what happens.

anyways even if they do put out 9v having charging circuitry right in the pedal would be a nice touch.

Re: Digital Power Supplies.

Posted: Sun Dec 12, 2010 5:22 am
by McSpunckle
Definitely want something universal, and anything below 9V could kinda suck in an analog circuit.

I don't have one, but: http://www.sparkfun.com/products/10053

Read the comments. I've read similar things about most rechargeable 9 Volts. To be fair, they get down to that level pretty quick.

If they could handle the current, a standard 3.7V cell could be used, and just pumped up to 9. On Sparkfun they come up to 2000maH, which is quite a lot more than a standard 9V battery. It'd probably still better to bump the standard 9V sized batteries to 9V, though. I haven't looked too much for other cells/chargers. I had a glance at Mouser, and that would be way way more expensive. Google is showing most Lithium-Ion batteries come in a bit less than 9V, but so do most other rechargeable.

There are other technologies, tough.

http://www.greenbatteries.com/ma.html

I'm pretty sure the charging circuitry on these is stupidly simple, and it could be switched with a simple transistor switch, but it would need something to stop it from over-charging. :idk:

Re: Digital Power Supplies.

Posted: Sun Dec 12, 2010 6:00 am
by Wizard
my 1-spot powers 8 pedals fine so far, whats it's limit?

Re: Digital Power Supplies.

Posted: Sun Dec 12, 2010 7:17 am
by McSpunckle
1 amp. It'll power A LOT of fuzz pedals.

A tubescreamer is about 6mA. Most simple fuzzes are about 3mA. Divide that into 1000. Yep.

-edit-

Actually, 1.7 amps. Or 566.7 Fuzz Factories.

... I never realised that.

Obvs, anything but fuzz/distortion uses a lot more juice.

Re: Digital Power Supplies.

Posted: Fri Jan 07, 2011 5:11 pm
by Bellyheart
In the case you didn't see

viewtopic.php?f=149&t=14385

Re: Digital Power Supplies.

Posted: Fri Jan 07, 2011 7:10 pm
by multi_s
Bellyheart wrote:In the case you didn't see

http://ilovefuzz.com/viewtopic.php?f=149&t=14385


niiice thanks i actually didn't see that :)
McSpunckle wrote:Definitely want something universal, and anything below 9V could kinda suck in an analog circuit.


ya you could easily avoid this by using an inverter/boost converter or something though. it might seem extreme to some people to have something so advanced just dealing with the power supply but mcus are so cheap now, its really not that unreasonable. a decent mcu + inductor/whatever switch costs about as much as one decent 9v battery.

Re: Digital Power Supplies.

Posted: Fri Jan 07, 2011 7:17 pm
by tuffteef
McSpunckle wrote:Drag soldering is kinda fun!



your crazy :lol:

Re: Digital Power Supplies.

Posted: Sat Jan 08, 2011 2:35 am
by McSpunckle
Bellyheart wrote:In the case you didn't see

viewtopic.php?f=149&t=14385


Fuck. Now I have to add a battery level indicator.

Re: Digital Power Supplies.

Posted: Sat Jan 08, 2011 10:17 pm
by the Life Aquatic
ive got the godlyke power all, considerably less noise than the one spot, and i can power moar pedalz :!!!: