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SanDisk Senior User
Posts: 101
Registered: ‎01-27-2008

Sansa View 16G Current Draw

With a roughly 75% charged battery, the current draw into the bottom connector was approximately 250 ma or 0.250 amperes, this gradually tapered off to 6 ma and stayed there, must be a standby load current into the unit.

Assuming all current is from the test rig with a fully charged battery, switching the unit on with the back light display at full brightness the current draw is 151.2 ma, I didn't play with the brightness, but when the light switched off the current dropped to 62 ma, no headphones were plugged in.

Playing a song with a pounding base, the current fluctuated between 62 to 64 ma, and ironically did not change by plugging in headphones, nor did it change by changing the volume control from minimum to maximum, standard 32 ohm headphones were used. 

Showing photos or a video draws the same current as the back light being on that is about 2.4 times the current draw when just listening with the back light off.

To get up to 35 hours of operation, at least a 2,200 mah battery must be used, I did not break open the case to verify this, ha, wife would kill me.  Do have a high output Fuji 1,800 mah battery that is twice the size of a 1,000 mah cell phone lithium ion battery, the 1,800 mah battery would fit inside of of View case, but wouldn't leave much space for anything else.  Not drawing any conclusion from this, but I have yet to see if the View would indeed run for up to 35 hours before a charge is required.

The above figures are based on just one View, totally unacceptable in engineering, least 100 sample units should be tested, preferably, over a thousand from different production runs.  But does give a ballpark figure as to what the View does draw.  My key interest was to learn if I could incorporate a charging circuit into the FM car modulator so we would have as half as many cords dangling around, looks very feasible.

Ha, could pack a 70 pound 100 AH marine battery on a back pack, so my wife could listen over two months of music without a charge and also get some exercise in the process.  But four Ni-MH 2,600 mah hour batteries with a DC to DC converter in addition to the internal battery, should give her about 80 hours worth.
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Newbie
Posts: 15
Registered: ‎02-12-2008

Re: Sansa View 16G Current Draw

HAHAHAHAHAHA 35 hours... yeah right.  I get about 8 if I'm lucky and don't use the screen ever.

It's a 730mAh battery. http://img231.imageshack.us/img231/6956/image0003zw5.jpg

I was very impressed with the e200... I don't have brand loyalty anymore after buying the View.  You can't even change the batterey in the View or even open it up!!!  This was very easy with the e200.
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Newbie
Posts: 15
Registered: ‎02-12-2008

Re: Sansa View 16G Current Draw

oh and BTW.. Pins 27 and 28 on the data port are right and left audio that outputs max volume no matter what volume the player is set on.  This is for use with the TV output, but I also made a cord for the aux input on my car stereo.  You would think that lower volume means less power needed, but it's always pumping at max volume on the data port anyway.  check http://www.anythingbutipod.com/forum/showthread.php?t=21632 for pinouts
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SanDisk User
Posts: 36
Registered: ‎12-26-2007

Re: Sansa View 16G Current Draw

[ Edited ]
I can get >25 hours MP3 play time from my View (volume at about 50%, display rarely on, various sessions over a week or more). But if I put a card in the micro-SD slot then this time reduces to less than 10 hours.

I would be cautious about using external connector power as a basis for battery life projections. It is quite possible that various power-saving modes aren't enabled when on external power.

John


Message Edited by JohnRatsey on 02-13-2008 04:49 AM
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Newbie
Posts: 15
Registered: ‎02-12-2008

Re: Sansa View 16G Current Draw

I use the microSD slot since I got my view... I'll try without.  I had no idea.  Thanks for the tip.  Maybe I should have went with the 16GB Smiley Indifferent
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SanDisk Guru
Posts: 5,822
Registered: ‎12-26-2007

Re: Sansa View 16G Current Draw

Interesting find!  I thought that once the device refreshes its database, it should know what's on the SD card, and the card should demand no juice unless being read or written to.
 
Is there a draw difference?
 
Firmware change?
 
SanDisk should know all there is to know about SD / flash memory...
 
Bob  Smiley Surprised
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SanDisk Fanatic
Posts: 281
Registered: ‎12-02-2007

Re: Sansa View 16G Current Draw

I used, my all days yesterday, ...   (from 8:15am - 11pm) 
I watched a movie, that was about 1 hour & 45 minutes..  (I listen to music all day at work, I never turn it off while at work)  My music profile, is I jump between rhapsody channels, different Genre's, and my "music to go" list....   
 
Does it go 35 hours?   I don't know because I charge it at night...  What I do know, is it has real world use...  As long as it can go all day with needing a charge, I'm good...
 
**MY 2 CENTS aka my opinion...    "Is it even worth 2 cents?"   lol...
My guess on where Sandisk got this claim of 35 hour battery life; is it was probably done using a math formula, rather than actually being used for 35hours.