mephistho
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Power from TV USB Port?

Mon Jun 25, 2012 11:47 am

Hi,

I'm owning a LG 37LV5590 Television. May I operate the Raspberry with the power from the TVs USB-Port? Would be quite convenient, since switching on the TV would as well switch on the Raspberry and no further power supply would be required.

How do I know the TVs USB provides sufficient mA and Voltage?

Cheers,
Andreas

mephistho
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Re: Power from TV USB Port?

Mon Jun 25, 2012 12:05 pm

I reckon at least an Y-Cable would be necessary

"A unit load is defined as 100 mA in USB 2.0, and 150 mA in USB 3.0. A device may draw a maximum of 5 unit loads (500 mA) from a port in USB 2.0"

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alexeames
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Re: Power from TV USB Port?

Mon Jun 25, 2012 12:22 pm

Try it and see. You won't do any harm by having a try. It might work perfectly, it might work intermittently, it might not work at all. Only one way to find out, regardless of what anyone says. :lol:

The USB voltage is standardised at 5.0 +/- 0.25 V
Whether or not it can deliver enough current, mA is the unknown question
Alex Eames RasPi.TV, RasP.iO

jamesh
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Re: Power from TV USB Port?

Mon Jun 25, 2012 2:21 pm

I run my Pi off the USB port on my desktop PC. Supposed to be limited to 500mA, but isn't. I reckon the TV will be much the same.
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alexeames
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Re: Power from TV USB Port?

Mon Jun 25, 2012 2:36 pm

jamesh wrote:I run my Pi off the USB port on my desktop PC. Supposed to be limited to 500mA, but isn't. I reckon the TV will be much the same.
That's pretty much what I thought. Never mind what all the standards say, plug it in and see. :lol:
Alex Eames RasPi.TV, RasP.iO

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Paul Webster
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Re: Power from TV USB Port?

Mon Jun 25, 2012 5:31 pm

Works fine from TV USB for me (Sony) - I added that info to the wiki some weeks ago.

AshleyD
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Re: Power from TV USB Port?

Mon Jun 25, 2012 6:42 pm

I used mine for the first time today - ran it off of a 32" Samsung LCD TV...worked fine! :ugeek:

cyrax65
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Re: Power from TV USB Port?

Tue Mar 19, 2013 12:34 pm

Mine is also directly powered by the USB port on my 32" LED TV, a feat I actually found was possible by accident. Everything is operational with no hiccups (for the time being...)

southcoaster
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Re: Power from TV USB Port?

Fri Feb 21, 2014 11:31 pm

I've been running mine directly off a 24" Samsung HD monitor and a 50" Sony TV. Seems to work fine in both instances but I havent' tried running the pi for over an hour yet.

I'm currently trying to write a script that will boot up Chromium, navigate to a specific webpage, log in to the site and proceed to a specific page (an analytics dashboard showing the statistics of the website I work on). I want this to happen automatically so the TV can be put on a sleep timer (or timer plug in the wall) and have everything turn off at night then boot and show the data automatically each morning.

martianable
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Re: Power from TV USB Port?

Mon Aug 04, 2014 6:54 pm

perhaps off-topic, but can you let me know how you're doing southcoaster ? I'd like a little help with a similar project - your idea is great - thanks !

davinchif
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Re: Power from TV USB Port?

Sun Sep 18, 2016 1:45 pm

I would do it with a y-cable. With a regular cable, I get a power warning (multicolour cube on the top right corner) when decoding HD video.
(Raspberry Pi 3, Philips TV)

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bensimmo
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Re: Power from TV USB Port?

Sun Sep 18, 2016 6:53 pm

Many TV ports are there to run drives from, so there is good chance they are providing more, just look up the TV specs. But do as most do (like above) and try it.
Laptop and computers also have this same answer, a lot now come with charging enabled ports so can provide 2A+
Again it's an open question. Now long is a piece of string? You don't know till you measure it.

Just don't look at the manual and the RS232 port on the back of the TV if there is one.

Some place near talk on USB http://www.manualslib.com/products/Lg-3 ... 56987.html

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