Hw-133-v1.0 Datasheet

Dust and residue on the sensor pad can act like water. The datasheet implies pure water; reality says clean your sensor with alcohol regularly.

/*
  Hw-133-v1.0 Rain Sensor Demo
  Reads digital (rain alert) and analog (water level) values.
*/

const int DIGITAL_PIN = 2;  // DO pin
const int ANALOG_PIN = A0;   // AO pin


void setup() 
Serial.begin(9600);
pinMode(DIGITAL_PIN, INPUT);
Serial.println("Hw-133-v1.0 Sensor Ready");
 Hw-133-v1.0 Datasheet


void loop() 
int digitalValue = digitalRead(DIGITAL_PIN);
int analogValue = analogRead(ANALOG_PIN);


Serial.print("Digital (DO): ");
Serial.print(digitalValue);
Serial.print(" 
 Dust and residue on the sensor pad can act like water

  • I2C bus:
  • Power:

    • Interfacing the Hw-133-v1.0 with a microcontroller is straightforward. Below is the most common connection for an Arduino Uno. I2C bus:

  • Pass criteria: Device ID correct, register R/W error rate <0.01%, ADC offset/gain within specified limits, no thermal exceedance.

    • Unlike complex ICs, this board is simple. Looking at the 4-pin header, you will find: