Hi!

I need to discharge some NiMH cells (AA type) one at a time. This is 
easy to do with an extra power supply, but can it be done with just the 
power the cell is delivering ?

Requirements are:

   .- Number of cells: one AA size.
   .- Discharge current: any fixed value between 1A and 2A is ok, higher 
with less parts is better.
   .- Stop discharge: when cell is at 1.0 volt.

I was thinking on using a DC-DC converter, like the LT1110 (minimum 
input voltage is 1.0V) to power up some parts, like a MOSFET to 
discharge the batt. The lower voltage threshold can be sensed by the 
LT1110 itself or not ...

Or maybe a simple Joule Thief can power the discharger MOSFET, but I 
need to know when to stop ...

Maybe better is to use a power transistor, as it requires a lower 
voltage than the MOSFET to be on ...

Maybe no DC-DC converter at all, just something that runs with as low as 
1.0V ...

Any idea would be really appreciated.

Thanks,
Diego.
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