Simple Circuit using LED to alert low voltage - But I need lower threshold

ebeowulf17

Joined Aug 12, 2014
3,274
Well, I did a little playing around in LTSpice. I'm sure none of these component values are quite right, especially after switching to a different part with a lower reference voltage, but I just wanted to get an idea how this circuit behaves. If this sim is any indication, a cap from the voltage divider output to ground can work in conjunction with the existing resistors as a reasonable low pass filter.

low-battery_zener-ref_01.png
 

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Lumenosity

Joined Mar 1, 2017
614
So I finished making the circuit that does this nicely using the TLV432 (Thanks Bordo).
It comes on right at 2.8v (the circuit has 2, NiZn AA batteries at 1.6v each.)
It works precisely as intended. Simple, but helpful (to me).

LowBatteryWarning.jpg
 
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