> Could you draw a simple schematic on how this "clamp" works? I'm not real=
ly
> understanding it.


Rushing ..
Look at the TL431 data sheets about how to make a high power preision zener=
..
Can be a transistor and a 431 - not even an opamp.
When V get's to limit 431 is programmed to turn on and this urns on a
clamp transistor.
Data sheets will have ap motes of this.
No opamp.
Per battery =3D 431, pnp, 4 resistors probably. Cheap.
More in due course if needed - have a look at data sheet.

=A0 =A0 =A0 Russell

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