LM393 – Comparator Module
The comparator module is used to digitize any resistive sensor. The module produces an output voltage according to the resistance of the connected sensor and is made available at Analog Output (AO) pin. The same signal is fed to an LM393 High Precision Comparator to digitize it and is made available at a Digital Output (DO) pin. The module has a built-in potentiometer for sensitivity adjustment of the digital output (DO).
You can set a threshold by using a potentiometer; So that when the sensor resistance goes low beyond the comparator threshold value, the module will output LOW otherwise HIGH.
Apart from this, the module has two LEDs. The Power LED will light up when the module is powered. The Status LED will light up when the digital output goes LOW.