Quote:
Originally Posted by Popup
I took apart my unresponsive K3 the other day, and measured the battery voltage. To my surprise there was a grand total of 0V between the '+' and '-' terminals!
There was also 2.8V between either of these and either of the SDA/SDC terminals. I'm not a stranger to I²C, and there are typically pull-up resistors on both the data and clock lines, so maybe that shouldn't be so shocking.
So, here are my questions: - Is it normal that there is no voltage whatsoever between the terminals of the battery? (I mean, it could be that there's some kind of I²C handshaking necessary before the battery connects it's cells to the outside world, but it sounds curious.)
- Is it normal that the battery/kindle I²C connection works with 2.8V? (I'm more used to 3.3V, but hten I haven't worked with modern consumer electronics, where I understand that all voltages creep downwards.)
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The battery management is on the SPI controller, not the I2C controller.
No, that is not normal - the battery terminals are battery terminals.
The full charge on the K3 battery brings it up to nearly 4.2v.
The SoC will detect a low voltage condition, slow to appox. 1/10 the normal clock speed and run at 2.8 - - -
Intended I suppose to run "just enough" to control the charger.
It is very likely that battery is dead now from over-discharge.
It is also very likely that the battery management in the Kindle will not be able to recover the battery from that discharge level, although an external Li-Ion charger might be able to do it.
If the K3 is still under warranty - send it home.
That is where mine is headed.