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LM3914 Battery Level Monitor Answered

I am trying to make a Battery Level Indicator using the LM3914 IC. The problem I am facing is... where you see those 3 LED's my voltage increases on the pot, where as when the LED's are all the way on it decrease across the pot. I am using a 9V Battery where I want the red led to show depletion  of battery life around 5 or so volts  how can I achieve this. Can someone please help me with this?




2 years ago

The LM3914 has a "dot" mode (not a bar), which would work if you want a single indicator.

Just use one LED for your "low voltage" light.

Yes, it's either dot or bar, not both. From the datasheet:

"Bar or Dot Display Mode Externally Selectable By User"

I HAVE seen a funky mode where the dot was one ahead of the bar. Can't remember if it's still on the datasheet.

Cool. Feature or hack?

I believe there's a bar mode that holds a dot peak. Pretty useful for audio, as it's the transients that cause "pops" in recording.

Mmm. Try current data sheet figure 18.