0

Good source for wall 9V wall warts?
Moderators: adafruit_support_bill, adafruit

Please be positive and constructive with your questions and comments.

Good source for wall 9V wall warts?

by rizla420 on Fri Apr 09, 2010 2:42 pm

Hey guys/gals,

Know of any good places to pick up some affordable 9v wall warts? I went to my local electronics shop (!"The Shack") and they seemed pretty expensive for a 9v (12-15 bucks) Is that typical? Ada sells em for 7 bucks which is better, but with shipping etc, it adds up. I found some for 3.50 on ebay (China) whcih seem good but who knows the quality. Also, for boarduinos can i supply it with 9V 1amp or should i stick with a 9V 600mA?

rizla420
 
Posts: 332
Joined: Thu Feb 05, 2009 9:03 pm

Re: Good source for wall 9V wall warts?

by adafruit_support_bill on Fri Apr 09, 2010 2:53 pm

Any old 9V wall wart should work. You don't need a high-quality regulated unit, since the BoArduino has an on-board regulator already.

9v @1A is no problem The BoArduino will only draw what it needs.

adafruit_support_bill
 
Posts: 75263
Joined: Sat Feb 07, 2009 10:11 am

Re: Good source for wall 9V wall warts?

by rizla420 on Fri Apr 09, 2010 3:16 pm

arduwino wrote:Any old 9V wall wart should work. You don't need a high-quality regulated unit, since the BoArduino has an on-board regulator already.

9v @1A is no problem The BoArduino will only draw what it needs.



Given that, lets say i had some power hungry led arrays, would having a wall wart that puts out more amps be better or would the boarduino only supply what the pins can output?

rizla420
 
Posts: 332
Joined: Thu Feb 05, 2009 9:03 pm

Re: Good source for wall 9V wall warts?

by sirket on Fri Apr 09, 2010 3:28 pm

rizla420 wrote:Given that, lets say i had some power hungry led arrays, would having a wall wart that puts out more amps be better or would the boarduino only supply what the pins can output?

That depends on how you are driving the LED's. If you are driving them from the boarduino- the current is going to be whatever the boarduino can supply (or sink). If you're using transistors or some other method of driving the LED's- then it could be much more. That said- I've driven a LOT of LED's and still been well under an amp.
Last edited by sirket on Fri Apr 09, 2010 3:46 pm, edited 1 time in total.
sirket
 
Posts: 128
Joined: Fri Oct 26, 2007 8:46 pm
Location: NYC

Re: Good source for wall 9V wall warts?

by rizla420 on Fri Apr 09, 2010 3:35 pm

sirket wrote:
rizla420 wrote:Given that, lets say i had some power hungry led arrays, would having a wall wart that puts out more amps be better or would the boarduino only supply what the pins can output?

That depends on how you are driving the LED's. If you are driving them from the boarduino- the current is going to be whatever the boarduino can supply. If you're using transistors or some other method of driving the LED's- then it could be much more. That said- I've driven a LOT of LED's and still been well under an amp.


I'm driving the LED's with '595 shift registers powered by the boarduino. I guess i'll have to wait till my pcb's get made and see how "well" it works. i'm driving some bring LED's about 10,000mcd

rizla420
 
Posts: 332
Joined: Thu Feb 05, 2009 9:03 pm

Re: Good source for wall 9V wall warts?

by sirket on Fri Apr 09, 2010 3:50 pm

rizla420 wrote:
sirket wrote:I'm driving the LED's with '595 shift registers powered by the boarduino. I guess i'll have to wait till my pcb's get made and see how "well" it works. i'm driving some bring LED's about 10,000mcd

In that case the boarduino current is irrelevant- the 595 is supply the current- so whatever it can suplpy is what you are limited to.

I'm driving 32 3,000mcd UV Led's at 13.6 volts at 160ma (8 strands of 4 LED's dropping 3.4 volts per LED with no resistor). At 3.4 volts this would be 640ma. I'm stilling looking for abetter way to monitor the current so I can adjust the voltage- but right now- it's working well.
sirket
 
Posts: 128
Joined: Fri Oct 26, 2007 8:46 pm
Location: NYC

Re: Good source for wall 9V wall warts?

by adafruit on Fri Apr 09, 2010 4:07 pm

you're not likely to find good switching supplies for much less than what we sell them for at adafruit - they're just more expensive than unregulated supplies. transformer-based supplies are much cheaper tho, you can get them for $2 or so at surplus shops

adafruit
 
Posts: 12151
Joined: Thu Apr 06, 2006 4:21 pm
Location: nyc

Re: Good source for wall 9V wall warts?

by westfw on Fri Apr 09, 2010 8:06 pm

To get ONE power supply, head out to a thrift store and see what they've got hanging on the rack of supplies that have been sadly separated from their original devices. Those poor orphans tend to sell for about $2, and YOU could give one a good home. Sniff. 9V is less popular than it used to be, though (don't forget that it doesn't have to be exactly 9V.)

For a tested and repeatable experience, the supply sold by Adafruit looks like a really good deal.

If you have to pay $15, I'd start looking for a toy at that price that includes a wall wart of the appropriate voltage. Old-style (dumb) 4xAA battery chargers, cordless phones, etc...
westfw
 
Posts: 1582
Joined: Fri Apr 27, 2007 1:01 pm
Location: SF Bay area

Please be positive and constructive with your questions and comments.