Does Microsd card drain your ereader battery power?

[HarryT]

Originally Posted by calvin-c

That's up to the device. The card doesn't require any power when it's not being used-but some devices might send power to it anyway. Others don't. Like I said, it's up to the device.

The standby current is required for the device to be able to check the status of the card (eg to see whether or not a card is actually present in the slot), so I would imagine that most devices would power the card whenever the reader was "awake". But that's just guesswork on my part. Perhaps, as you say, there are some that don't.

[Skillganon]

Got a 4GB card in my sony T2 if it affects battery life I cannot see any significant difference with or without it.
Battery lasts for weeks and I read a lot of books

[calvin-c]

Originally Posted by HarryT

The standby current is required for the device to be able to check the status of the card (eg to see whether or not a card is actually present in the slot), so I would imagine that most devices would power the card whenever the reader was "awake". But that's just guesswork on my part. Perhaps, as you say, there are some that don't.

You're likely right as far as ereaders go. My phone & computers do exactly that-but my camera doesn't as far as I can tell. I should have clarified that it likely depended on the type of device but my point was that it really doesn't depend on the card itself.

And with all the 'multi-purpose' devices being developed I suspect that most new devices will work exactly as you say. I'm more familiar with older devices-I like things that I buy once & continue using for years. Sometimes for decades.

[medard]

There's a note in the Sony T2 manual that content on the microSD card will drain battery power.

Excerpt from the manual:

Spoiler:

Power-consuming operations

The following may require more power than normal
reading operations.

 Wi-Fi communications
 Constantly updating the [Wi-Fi Networks] list
 Displaying graphic-intensive books, files or Web sites
 Displaying a slideshow with a short interval setting
 Using a microSD card
 Frequent insertion and removal of a microSD card
 Having a large volume of content stored on a
microSD card
 Annotations, keyword searches and dictionary
searches
 The Wi-Fi network feature of the Reader is not in
standby mode.

[theducks]

Require More is not equal to Drain

IMHO that list is garbage. Many items appear more than once with different wording.
file size causes more draw ? Ok, given that the file may need to be read longer (more bytes), but whu is that different than the internal Flash


200 microamps is nothing when compared to a page flip processor usage.

That 200 microamps is probably 0 when the processor sleeps between pages.

WiFi and Backlights are the big draw. The former can be shut down. Don't have a Sony, so I don't know the power saving options available.

[Ken Maltby]

Originally Posted by HarryT

No, that's not what I was referring to. I meant that whenever an SD card is inserted into your reader, it will draw a (very) small account of power from the device, even when not actually being accessed; this is called the "standby current". It's a tiny amount, but it's not zero. A typical standby current would be about 0.2mA, compared to perhaps 80-100mA when the card is being accessed.

I would have to admit that any device needs to have a means to detect
that an SD card or other storage media is connected, a constant current
applied to a pair of pins in the interface could be one means used, but it
would be a poor device that required any appreciable power draw from the
battery. For any practical purpose, including any effect on the time provided
by a charge, there would be no effect what so ever.

Luck;
Ken

[JD Gumby]

Originally Posted by Ken Maltby

Hmm... it looks like you own a couple of the Kobo devices, so you can certainly provide information on their workings and your experience with them but where did you get the idea that all other devices function as you describe? You didn't
mean to say that the "Micro-SD" cards themselves are causing the creation of thumbnails, I hope.

No, it's how Kobo handles microSD cards and I said nothing about other devices. Before a relatively recent firmware update (2.3, I think it was, might've been a 2.1.x), it used to create a thumbnail for books on microSD cards as soon as they were detected and scanned, and stored those thumbnails for future use in the Kobo's internal storage. After the update, it stopped storing them and instead creates the thumbnail (which, of course, has to be read from the file) every time it's needed. That causes a lot of extra battery drain.

[Ken Maltby]

Originally Posted by JD Gumby

...unless you're using a Kobo device, then the use of a microSD card will cause quite a bit of drain thanks to it now creating temporary thumbnails on the fly for books on the card instead of creating the thumbnails once (either at indexing or the first time a book comes up when browsing your library) and storing them on the device.

Sorry, my fault. I read the above without reading the portion of "Harry T"'s
post that you had quoted. Somehow I read that as "Unless you are using a
Kobo device" then following will happen, my mistake.

Luck;
Ken