Question regarding a hunt for power supplies

[Veniogenesis]

Hi everyone!

I had a quick question regarding buying a wall plug power supply. I lost the power supply of a small amplifier that I have. The back of the amplifier says that the power requirements are 12 volts DC and 4 watts. I tried looking around on Mouser but couldn't find a power supply with those exact ratings (basically 12 volts dc, 0.33 amps, 5 watts I believe). I did however find a power supply rated at 12 volts DC and 5 watts. Is the watt rating the maximum or should I not play around and instead try to find a power supply with the exact ratings that are required? Do you guys have any suggestions as to what other sites I should look on for wall plug or desktop power supplies? Thanks so much everyone!

Cheers,

Venio

[Veniogenesis]

Oops, my bad everyone! I just realized that my question may have been a foolish one if my intuitions are correct. My experience tells me that it is okay to have a higher wattage rating on the power supply (as long as the voltage rating is correct)? Or am I just simply spouting nonsense again. Hopefully I'm not too far off.

(P.S. I would still be interested in other sites that sell power supplies. )

[grawk]

You want something with the right voltage rating, and a higher amperage rating than the device specifies, generally. But 12v .333a is 4 watts, not 5...

[philodox]

I've had really good experiences with the Pyramid Gold PSU's on eBay. You can adjust the voltage, they're regulated, and they make a 1.5amp unit I think, which should be fine. I use a 3amp unit with my T-Amp.

[n_maher]

Just be aware that the higher you spec the amperage the more overshoot you're going to get. Most likely the amp is equipped to deal with this to a certain degree but I wouldn't use 1.5A wallwart in a situation that spec'd a third of an amp, odds are pulling that little bit of current the 1.5A PS is going to run pretty high output voltages, which could be a bad thing. You shouldn't have any issue finding a 12V/.5A wallwart at Mouser or Digikey, if you do let me know and I'll poke around and see what I can find for you.

[Veniogenesis]

You want something with the right voltage rating, and a higher amperage rating than the device specifies, generally. But 12v .333a is 4 watts, not 5...

Oh yes. My bad, I meant that I needed 12v, 0.333a, 4 watts.

Just be aware that the higher you spec the amperage the more overshoot you're going to get. Most likely the amp is equipped to deal with this to a certain degree but I wouldn't use 1.5A wallwart in a situation that spec'd a third of an amp, odds are pulling that little bit of current the 1.5A PS is going to run pretty high output voltages, which could be a bad thing. You shouldn't have any issue finding a 12V/.5A wallwart at Mouser or Digikey, if you do let me know and I'll poke around and see what I can find for you.

Ah ha, I see. Thanks for the tips! So I'm guessing it's fine if I have a 0.4 or 0.5 amp PSU and an amplifier that wants 0.33 amps, it should sort of be okay.

[Veniogenesis]

it won't sort of be ok, it'll be ok.

Nice.