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LM3914 battery level Indicator ?

https://www.instructables.com/community/LM3914-Battery-Level-Montitor/     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?      Which pin can I set to 5v and how?

Picture of LM3914 battery level Indicator ?
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iceng1 year ago

You cannot use the LM314 to measure its own voltage.

You can run the LM314 on a second 9v battery and measure the change of that first battery.

If you want to measure 9 to 5 volts and power the instrument with the same changing supply .... Use a 3.3 volt micro processor running off a regulator that accepts 9v or 5v or 35v and regulates an uninterrupted 3.3v for the uP .... Then it is a simple matter of using a quad Op-Amp or the ADC on the uP to light the three LEDs as you like.

GREEN 9.9-7.51volts___ YELLOW 7.5-5.01volts___RED 5-4volts.

yes you can. You need the reference volts to be a fraction of the rail

dominick.j.pezza (author) 1 year ago

I just test my method and it works. the problem is that I could not tell where the voltage was at 5 out of ten leds lit

dominick.j.pezza (author) 1 year ago

I now know why I canot find the solution to the problem its due to me not having a digital votage reference, to put onto the breadboard that way I can see what resistors I need for a 5v voltage

rickharris1 year ago

The 3914 drives the LEDS - alter the order you connect them to the pins of the 3914.

In your case this will mean connecting to the bar graph with wires rather then direct through the bread board.

dominick.j.pezza (author) 1 year ago

this is what I came up with/ also tutroials that I just don't understand

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rickharris1 year ago

Can we have a circuit diagram for what your trying to do please.