[ltp] battery dead?

[James Holden]

Quoting Kelvin KAN <kelvin@hongkong.sgi.com>:

...
> I remember someone also in this mail list suggested it was due to the
> voltage dropped below the minimum required by the microcontroller within
> the battery.  The fix was to apply 6V and 1/10 current of the mAh spec
> of the battery to the +/- terminus, to wake it up.
> 
> I've never done that due to the fact that a constant-current power
> supply would be comparable with the price for a new battery.
> 
> Has anyone got a cheaper source of constant-current power supply?  Like
> the circuit of building a fixed-volt&amp one (because we know we need
> exactly 6V/0.18A) using very cheap passive components (assuming the
> unregulated power is from the existing TP600 16V power supply). 

You can't build a PSU which supplies constant current *and* constant voltage at
the same time. You fix one or the other, and Ohm's law does the rest. 8-)

I can see how the situation has arisen though. TP batteries have several
connections to them, anybody got any ideas of the pinout, or even better, a
schematic?

James


-- 
James Holden, Leeds, United Kingdom
james-at-microcosmos.co.uk
In a world without boundaries, who needs Gates?

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