[Lenny400] Replacement batteries

[David Boddie]

On Monday 6. April 2015, Daniel Glöckner wrote:
> On Mon, Apr 06, 2015 at 02:23:28PM +0200, David Boddie wrote:
> > What constraints on the battery, other than 7.4V, the size and maybe also
> > the capacity do I need to be aware of? I'm mostly thinking about issues
> > related to the recharging circuit in the minibook itself.
> 
> The capacity is not a constraint.
> 
> The Letux 400 uses a TI BQ2057W for charging. It will stop charging
> when the battery reaches 8.4 V:
> http://www.ti.com/product/bq2057w/description

I'll add that to my collection of documents. Thanks!

> The sense resistor is 0.2 Ohm and it uses high side sensing, so the
> battery must sustain being charged with 0.7 A.
> 
> Both R_T1 and R_T2 (see BQ2057 datasheet) are 1.5 kOhm resistors,
> if you want to add a thermal protection circuit to the battery.

Thanks for the useful information. I'm not sure if I'll do much with
replacements just yet, but it will be good to be aware of this sort of detail
if/when I do.

Regards,

David