[JiggaD369]

I need to power a small DAC which has a requirement of 12V power source. I was thinking about replacing the wallwart with a DIY PSU and was intended on building a Gold Reference regulator but then came across the Hiface modding thread and saw the positive feedback of powering small devices with battery power.
 
So I got to searching and I see that there are loads of rechargeable batteries on Ebay and was wondering how can I use one of them.
 
Some examples...
 
http://cgi.ebay.com/DC-12V-2800mAh-Super-Rechargeable-Lithium-ion-Battery-/250745125931?pt=US_Batteries&hash=item3a6192fc2b
http://cgi.ebay.com/ZEUS-12VOLT-7AMP-SEALED-RECHARGEABLE-BATTERY-PC7-12F1-/160532386981?pt=LH_DefaultDomain_0&hash=item256079d4a5
http://cgi.ebay.com/1-pcs-12V-1300mAh-Rechargeable-Battery-Pack-Charger-/130471601169?pt=US_Batteries&hash=item1e60b6a411#ht_2851wt_909
 
I see that the chargers and the battery output use the same port so the battery has to be disconnected from the unit being power when I have to charge it, correct? OR is there a way I can use a switch to power the DAC and cut the charger and cut the power to the DAC and start the charging?
 
There are all kinds of batteries (li-ion, lithium, etc)..which one would make the most sense for this purpose? Or does it even matter? 

 

[beamthegreat]

It doesnt matter what kind of battery it is but be sure to buy a battery that matches your voltage and amp.

 

[beamthegreat]

wow, the second deal is very good. You should go for it if you can. 12 volts x 7 amp = 84 watts for 1$!!! but it will be an overkill if you're using it as a portable dac.

 

[JiggaD369]

beam,
 
Thanks! The DAC is my desktop DAC so it won't be going anywhere.
 
The manual states 12V/150mAh/1.25a and the wallwart is 12V/1.25A so I'm guessing that the DAC requires 150mAh?

 

[beamthegreat]

uhh no. Mah (Milliamps per hour) is the Capacity of the battery so the more Mah the better but the amp and voltage has to be exact. If you feed the DAC with too much volts or amps, it might break. 

 

[beamthegreat]

Btw, the second deal isnt gonna work for you because it gives off too much amps and I cant guarantee that your dac will work because none of the description says how many amp it gives. Try asking the seller, and if the specs match, it should probably work.

 

[JiggaD369]

Hmm now I'm confused. So the DAC requires 12V, which the battery provides. BUt what about the amps? None of the batteries states that.

 

[revolink24]

uhh no. Mah (Milliamps per hour) is the Capacity of the battery so the more Mah the better but the amp and voltage has to be exact. If you feed the DAC with too much volts or amps, it might break. 

It is not milliamps per hour but milliamp hours. Also, 150 mAh is a very low capacity, so I'm guessing those batteries are intended to be used as cells in parallel.

 

[JiggaD369]

Quote:

Quote:

uhh no. Mah (Milliamps per hour) is the Capacity of the battery so the more Mah the better but the amp and voltage has to be exact. If you feed the DAC with too much volts or amps, it might break. 

It is not milliamps per hour but milliamp hours. Also, 150 mAh is a very low capacity, so I'm guessing those batteries are intended to be used as cells in parallel.

Revo,
 
Thanks for the clarification. But the DAC is what states 12V/150mAh in the manual and 12V/1.25A on the wallwart. The battery I'm looking at is 12V/3000mAh.
 
So I'm trying to find out if the battery will work if I just cut the cord from the wallwart and connect it to the battery.

 

[revolink24]

Quote:

Quote:

uhh no. Mah (Milliamps per hour) is the Capacity of the battery so the more Mah the better but the amp and voltage has to be exact. If you feed the DAC with too much volts or amps, it might break. 

It is not milliamps per hour but milliamp hours. Also, 150 mAh is a very low capacity, so I'm guessing those batteries are intended to be used as cells in parallel.

Revo,
 
Thanks for the clarification. But the DAC is what states 12V/150mAh in the manual and 12V/1.25A on the wallwart. The battery I'm looking at is 12V/3000mAh.
 
So I'm trying to find out if the battery will work if I just cut the cord from the wallwart and connect it to the battery.

You might want to ask in the DIY forums just to be sure, but I'm pretty sure you'll be okay with any 12V battery or wall wart if the DAC takes 12VDC.

 

[tjohnusa]

150 milliamps is actually .15 amps. If you measure a plug in power supply rated for 12 volts without a load it will probably read 14 volts or more, it should regulate to 12 volts under load. As long as your DAC is working properly you can have a power supply with a larger current because the device will only use what it needs, if you get a component that blows then you will have problems because the current draw will max out to the supply current available and in worst case senario can cause a fire if a fuse doesn't blow first.