A discharged battery and the analog comparator

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#1
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I have an existing, portable sign board using an attiny2313 to send data to four driver IC's. The drivers control 202 red LED's. The LED's are arranged in blocks of three from each driver pin. (No multiplexing)
There is a new demand for the board to be powered by a 12V sealed lead acid battery. Ideally, I'd like an A/D port to monitor battery voltage. (Read the A/D port every 100mS if there are 10 consecutive readings where the battery is below 10V, shut down the driver IC's)
All I have on the board is a voltage divider going to an analog comparator pin and the other pin of the analog comparator has a stable 2.5V reference.
From looking at the datasheet, it seems the comparator is only edge triggered. What I'm concerned about is the analog comparator false triggering on a slow power up. (Or maybe because of electrical noise from moving or bumping the cigarette lighter power connector) The comparator is set to interrupt when the battery voltage is 10V.
This is my question: If you had only an analog comparator, what would be the best way to determine when the battery voltage was low, while minimizing the chance for a false low battery reading?
Matt

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ACIS1, ACIS0: Analog Comparator Interrupt Mode Select
You can change this to change sense of generating interrupt.
Also reduce the noise of the entire circuit.You can also do a high to low interrupt sense for it.