Here we connect 3 3v 5v of external power.
Arduino soil moisture sensor circuit.
This establishes power for the sensor.
The sensor has 4 terminals for connection vcc for power gnd analog output and digital output.
The soil moisture sensor module built around the lm393 comparator gives an active low l level output when the soil is dry determined by a pre setted threshold value.
We connect vcc to 5v on the arduino board and gnd to gnd on the arduino.
The arduino soil moisture sensor circuit we will build to read the moisture of soil is shown below.
The sensor module contains a potentiometer with it which is used to set the threshold value.
Let s start with the i2c 16 2 lcd.
This soil moisture sensor circuit is pretty simple.
Vcc and ground are how the sensor gets the power it needs to operate.
I2c 16 2 lcd 12vdc water pump and capacitive soil moisture sensor interfacing with arduino uno.
If you type in arduino soil moisture sensor into ebay you will see the complete type of sensor needed to build this circuit.
All the 16 pins of the pcf8574 driver module are connected with the lcd pins.
Digital mode interfacing arduino and soil moisture sensor to connect the soil moisture sensor fc 28 in the digital mode we will connect the digital output of the sensor to the digital pin of the arduino.
We can adjust the threshold using the potentiometer in the sensor.
To connect the soil moisture sensor fc 28 in the digital mode we have to use digital output of the sensor and a digital input of arduino.