Dual power 5v & 12v for Raspberry and LCD controller

euser1984

Hi,
I have this for a picture frame project http://www.ebay.ie/itm/111743845103?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

Above needs 12v but I can't figure out how many amps it needs??? Tech specs don't tell me http://img.ozdisan.com/ETicaret_Dosya%5C441291_5506225.pdf

The raspberry pi needs 5v - would psu options are available to get all the power from one device....

Thanks

12v house alarm battery + USB Outlet/ boost pack
ATX PSU
Server PSU.

..loadsa amps
Best way to find out max. current is measure it at full load.

euser1984

Out of curiosity I'm trying to light up an inverter here that takes 12v....none of the 12v psus I have seem to have enough current though.

However, higher voltage ones do have enough current....if I use the higher voltage power supply will the inverter only pull the voltage it needs?

euser1984

Out of curiosity I'm trying to light up an inverter here that takes 12v....none of the 12v psus I have seem to have enough current though.

However, higher voltage ones do have enough current....if I use the higher voltage power supply will the inverter only pull the voltage it needs?

What kind of inverter?
You need more current not volts. You'll fry it if you go too far outside the voltage threshold. Usually 16v is over-voltage on a battery inverter.

What PSU are you using. The inverter should only need mA when it's operating no load.

oscarBravo

euser1984 wrote: »

Hi,
I have this for a picture frame project http://www.ebay.ie/itm/111743845103?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

Above needs 12v but I can't figure out how many amps it needs??? Tech specs don't tell me http://img.ozdisan.com/ETicaret_Dosya%5C441291_5506225.pdf

The raspberry pi needs 5v - would psu options are available to get all the power from one device....

Thanks

Current draw is going to depend on the panel. You'll need to connect a panel and measure the current draw.

Digikey do a number of 5V/12V dual-output power supplies. This is the cheapest I can find.

ozmo

Could also use a PC power supply - possibly salvage one for free - the ones from the racks and Shuttle pcs (1U size) are very compact and you get a 5V and 12v at decent amps. adverts.ie might yield results.

Or some of the older 3.5 Inch external harddisks sometime come with a high amp power brick that supply a 12V and 5V. XBox 360 psu has 12v +5v +3V3 so thats an option also.

lots available in china cheap if you dont mind waiting 6 weeks:
http://www.dx.com/s/12v+5v+dc+power+supply

If you have an old satellite receiver box, old tv box etc - they are frequently thrown out - but inside there is often a separate switchmode 12V and 5V psu board - plus you get a nice case for your project for free. Same with the old original XBox- There is a 12v 5v PSU in there.
(be careful with psu that are not in cases - modern psu normally use bleed resistors to discharge the caps when switched off - but still treat them with caution just in case it doesnt - charged capacitors can give nasty shocks & sparks)


Also - Sometime things that require 12V or 9V - actually just drop the voltage down to 5V - sometimes with an inefficient 7805 circuit - 5V the max the chips are going run at anyway - if you are adventurous, it might be possible to bypass the devices voltage regulator and give it just the 5V it needs.