An ambient light meter circuit

Here, you have my proposed circuit to be used as our first analog input example:

An ambient light meter circuit

An ambient light meter circuit schematic

It has a voltage divider consisting of the photocell and a 10K ohm load resistor as the input circuit, just like the one I showed you in the previous section.

Regarding the output part of this circuit and trying to keep things simple, I have reused the assembly of the traffic light, but this time, we will use it as a level indicator with four possible states: low, medium, high, and maximum, being represented by none, one, two, or three turned-on LEDs.

From the point of view of used pins, I have connected ...

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