Simple Battery Monitor Circuit Required

Not interested in guessing. But to put my original point into perspective, how would the general concept you have in mind vary if the battery was a 1.2 volt cell or a 300 volt UPS battery?

Now, the next question: How concerned are you with power consumption, both when the LED is on and when it is off?

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I suggest looking at a 1381 Voltage Trigger.

Not so clever, but here is a circuit that may work: (view in courier font, or other monospaced font)

Vin ---------o----------------. | | >| >| ___ Q1 |------. Q2 |------|___|-----. /| | /| 100k | | | | | | | | | | '-------o | LED V | | - .-. 6.2V - | 10k | | Zener ^ .------o | | | | | '-' | | .-. | | | 1k | | | | | | | | | | '-' | | | | | | | |-+ 2N5460 | | '---

I'm trying to think up a very simple circuit which will monitor battery level. Requirements are

Vbatt > Threshold --- LED is off Vbatt < Threshold --- LED is on Vbatt = Threshold --- Not fussed LED could be on or off Accuracy of t=Threshold is not too important

Here's the catch. I'm looking for a very low component count - I'm think a transitor, zener, LED and one or two resistors.

I can think of circuits using comparators, ICs, multi-stage transistors but I feel there is a clever circuit that I'm missing.

Clever ideas would be most welcome.

Cheers

Nigel

Sorry didn't think it mattered that much and I didn't want to constrain the creative juices - around the 6 - 6.4V mark. Nominal around 7.4V. Undepleted O/C voltage around 8.2V. Can you guess what it is?

Cheers

Nigel

use a schmitt trigger circuit

Look at

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Geese, what a lot of irrelevant questions!!!

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