EEVblog #370 - Kindle Paperwhite Teardown Review

[DarkPrince]

[free_electron]

that macronix flash ship holds the pixel voltages for the e-ink grid.

e-ink displays are difficult to drive , especially if you want ot do grey scale. the flash chip probably holds the correction factors for each pixel per 'shade' of grey

the little 4 pin chip cold be a hall sensor...

[tom66]

"A single charge lasts up to eight weeks, based on half an hour of reading per day with wireless off and the light setting at 10. Our breakthrough power management technology allows you to leave the light on at all times for the best possible contrast without sacrificing battery life."

This is double the life of the original Kindle they sell but only 28 hours, which gives an estimate (at 1420mAh) of 50mA. From a 3.7V cell that's about 0.19W.

I doubt the original Kindle used anywhere near that much (wasn't it supposed to be in sleep mode until you flicked a page?)  Perhaps they just made the battery smaller to get only 4 weeks on the cheaper Kindle.

At just 14 hours for the original Kindle, it's only a little short of the Kindle Fire, which does 11 hours.

What gives?

[Dread]

Loved the episode, but I really wanted to know more about the e-ink design
do you think you might teardown an older kindle so we can see more on how the display works?
Thanks for another informative episode I feel like buying a Kindle right now, the display looked really great. I wonder if it could ever be done in colour or is that just totaly impossible?

[stewartallen]

There is a switch that detects when you open or close the optional covers and turns the kindle on and off. I'm guessing it's a hall effect sensor and you where activating it with the screwdrivers magnetic tip.

[EEVblog]

Loved the episode, but I really wanted to know more about the e-ink design

I doubt there would be anything physically interesting to see.
All the interesting stuff would likely happen at the nano scale 

Dave.

[IanB]

based on half an hour of reading per day

Who are they kidding? Maybe that's meant to be an average. If I'm reading something absorbing like a novel, I will be reading 3-4 hours per day. Of course I can't read 3-4 hours every day, although if there were enough absorbing novels out there, maybe I would...

[EEVblog]

Of course I can't read 3-4 hours every day

Bingo!

Dave.

[Hypernova]

Half an hour? No way for me, I tend to go cover to cover in one settings if I can, that's anywhere from six to twelve hours.

[deathbydesign]

Half an hour? No way for me, I tend to go cover to cover in one settings if I can, that's anywhere from six to twelve hours.

Wow! I envy that you have that time to read in a day! You'd still have no problems with the Kindle's charge then. The Kindle's battery can last for 8 weeks if you read half an hour a day, which means approximately 28 hours of reading on a single charge. That means you could read for 12 hours straight and still have 16 hours left to spare!

[batterypowerguy]

The i2c bus is actually probably smbus for a fuel gauge/battery protection, seems like its smart enough to throw a repair error if its not getting an ack from the fuel gauge. Someone needs to take one of these batteries apart, I would love to see it, I wonder whos cells they are using? hopefully a brand name like BAK.

[tom66]

Cell origin Japan, so likely Sony.

[free_electron]

the displays are made by e-ink. http://www.eink.com/display_products.html
there is even a full color one.

the driver applies a high voltage to attract or repel the pigment particles. a single cell is essentially a capacitor and you 'store' a charge.
depending on positive or negative the pixel turns black or white. the storing is 'analog' meaning you have grayscale capability. there is compensation needed depending on adjacent cell charge and the display controller takes care of that.

controllers traditionally used to by ricoh but that division was sold to seiko/epson. Dialog semiconductor makes the high voltage controller while the 'brains' are made by epson , marvell and others.

you can buy sample kits of displays. they want 50$ and will send you 5 display. they have a few simple ones like a bargraph and some alphanumerical displays avaialble.

the only problem is : these are all polyimide film based and have no on board electronics. you are supposed to hot-melt the edge strip on a pcb containing the controller... good luck on that one. and the controllers are hard to get.

[AndreasF]

Quick question about the issue "PWM-control or not" for the LED brightness. In the video Dave says he sees no flicker on the camera and takes that as an indication that it is not PWM controlled.

I understand that you would expect flicker from some sort of aliasing between the relatively low (sample) rate of the camera and the higher PWM frequency, but would you always expect to see flicker, regardless how high the PWM frequency is? Wouldn't the flicker eventually disappear if the PWM frequency gets higher and higher?

[deephaven]

Quick question about the issue "PWM-control or not" for the LED brightness. In the video Dave says he sees no flicker on the camera and takes that as an indication that it is not PWM controlled.

I understand that you would expect flicker from some sort of aliasing between the relatively low (sample) rate of the camera and the higher PWM frequency, but would you always expect to see flicker, regardless how high the PWM frequency is? Wouldn't the flicker eventually disappear if the PWM frequency gets higher and higher?

Why not take a look with a scope? Even if the unit has been put back together, you could probably get enough pickup by wafting a scope probe near the LEDs if it was PWM.

[mikeselectricstuff]

Quick question about the issue "PWM-control or not" for the LED brightness. In the video Dave says he sees no flicker on the camera and takes that as an indication that it is not PWM controlled.

I understand that you would expect flicker from some sort of aliasing between the relatively low (sample) rate of the camera and the higher PWM frequency, but would you always expect to see flicker, regardless how high the PWM frequency is? Wouldn't the flicker eventually disappear if the PWM frequency gets higher and higher?

Yes - above a couple of hundred Hz you won't get flicker - with  indoor shooting the exposure time will be comparable to the  framerate so will integrate any PWM flicker. It's hard to get good current-controlled dimming, especially at low levels where part-part differences can become noticeable, and colour balance can shift, and PWM is simpler, therefore cheaper to do.

[andersm]

There's been many complaints about the Paperwhite's lighting being uneven at the bottom, with Amazon even acknowledging the issue. Since Dave said in the review that the lighting was great and even, is there variation between units, or is it only noticeable under some conditions?

[ataradov]

Since Dave said in the review that the lighting was great and even, is there variation between units, or is it only noticeable under some conditions?

It varies from device to device. There is also another issue, that prevents me from getting one - on some devices entire screen is covered by slightly colored spots, like interference patterns from thin films. Look at the customer's photos an you'll see it, looks pretty bad.

[TheWelly888]

An unfortunate Kindle customer had all her ebooks wiped off her Kindle and her Kindle bricked remotely by Amazon because she did something "illegal" with her contents. The kicker is that Amazon won't explain to her what she did wrong!!!

http://www.guardian.co.uk/money/2012/oct/22/amazon-wipes-customers-kindle-deletes-account

I've decided to stick with paper and my laptop!

[Bored@Work]

An unfortunate Kindle customer had all her ebooks wiped off her Kindle and her Kindle bricked remotely by Amazon because she did something "illegal" with her contents. The kicker is that Amazon won't explain to her what she did wrong!!!

http://www.guardian.co.uk/money/2012/oct/22/amazon-wipes-customers-kindle-deletes-account

I've decided to stick with paper and my laptop!

And you know what? Nothing will happen, unless that particular victim manages to create a shitstorm on the Internet. And if she manages she only might get kind of a refund. There won't be a change in the system. And there won't be much, if any, loss of sales for Amazon, because the average user simply does not care.

[ejeffrey]

The only way to fix this is to blow a hole in Amazon's 'you have no rights' click through contract.  Find a jurisdiction where that isn't enforceable, and have someone sue amazon for destruction of property.  Unfortunately, first sale is pretty much dead worldwide.  B@W is right on, no amount of media shitstorm is going to fix the underlying problem.  At worst, Amazon will just refund this woman and say "we are evaluating our procedures to hack into devices you purchased and delete your files to make sure we only do it to really bad people in the future".

But until what they did is correctly identified as a crime, you can expect only more of this.  But what is a crime for an ordinary person is responsible behavior for a company, at least if your corporation is big enough and your lawyers drive fancy enough cars.

[Bored@Work]

The only way to fix this is to blow a hole in Amazon's 'you have no rights' click through contract.  Find a jurisdiction where that isn't enforceable, and have someone sue amazon for destruction of property. 

Don't forget this requires deep pockets. You will have to buy the best lawyers money can buy. And in some jurisdictions you will have to buy the best judge money can buy, too.

You also have to have a lot of time and patience. Just in case Amazon decides it is in their best interest to drag this out for as long as they can, to make it expensive for you, and to break your will.

[TheWelly888]

And there won't be much, if any, loss of sales for Amazon, because the average user simply does not care.

Until Amazon comes for the average user - by which time it will be too late!

I have always suspected that digital media makes it easier for the authorities and corporations to keep tabs on what people read.

[rr100]

Whoa this is a nice discussion, have to return when I have a proper keyboard.
In the meantime can somebody let me know if the paperwhite kindle is DIM enough to comfortably read in the dark?

[rr100]

Bump...
Can somebody test the "paperwhite" kindle in pitch dark and give me some estimate if the brightness seems to go "low enough"? I have a galaxy note and while the screen is brilliant, literally, the amoled display seems to have only 24 or so levels and the lowest isn't low enough, not by a long shot.