How to Use FeeTech STS3032: Examples, Pinouts, and Specs

The FeeTech STS3032 is a high-precision temperature and humidity sensor designed for accurate environmental monitoring. It provides a digital output, making it easy to integrate into a wide range of electronic systems. With its compact design and reliable performance, the STS3032 is ideal for applications such as HVAC systems, weather stations, smart home devices, and industrial automation.

• HVAC (Heating, Ventilation, and Air Conditioning) systems
• Weather monitoring stations
• Smart home automation
• Industrial environmental monitoring
• IoT (Internet of Things) devices

The FeeTech STS3032 is engineered for precision and reliability. Below are its key technical specifications:

The STS3032 has a 4-pin interface for easy connection to microcontrollers and other devices. Below is the pinout description:

1. Power Supply: Connect the VCC pin to a 3.3V or 5V power source and the GND pin to the ground.
2. I²C Communication: Connect the SDA and SCL pins to the corresponding I²C pins on your microcontroller. Use pull-up resistors (typically 4.7kΩ) on the SDA and SCL lines if not already present in your circuit.
3. Address Configuration: The default I²C address is 0x40. Ensure no other devices on the I²C bus share this address.

• Avoid exposing the sensor to extreme conditions (e.g., condensation, high humidity for prolonged periods) to maintain accuracy.
• Place the sensor in a location with good airflow for accurate readings.
• Use decoupling capacitors (e.g., 0.1µF) near the VCC pin to reduce noise.

Below is an example of how to interface the STS3032 with an Arduino UNO using the Wire library for I²C communication.

#include <Wire.h>

// I2C address of the STS3032 sensor
#define STS3032_ADDRESS 0x40

void setup() {
  Wire.begin(); // Initialize I2C communication
  Serial.begin(9600); // Start serial communication for debugging
  Serial.println("STS3032 Sensor Initialization...");
}

void loop() {
  Wire.beginTransmission(STS3032_ADDRESS); // Start communication with sensor
  Wire.write(0xE3); // Command to read temperature
  Wire.endTransmission();
  delay(50); // Wait for sensor to process the command

  Wire.requestFrom(STS3032_ADDRESS, 2); // Request 2 bytes of data
  if (Wire.available() == 2) {
    uint16_t rawData = (Wire.read() << 8) | Wire.read(); // Combine two bytes
    float temperature = -46.85 + (175.72 * rawData / 65536.0); // Convert to °C
    Serial.print("Temperature: ");
    Serial.print(temperature);
    Serial.println(" °C");
  }

  delay(1000); // Wait 1 second before the next reading
}

• The 0xE3 command is used to read the temperature. Refer to the sensor's datasheet for additional commands (e.g., for humidity readings).
• Ensure the I²C pull-up resistors are properly connected for reliable communication.

1. No Data from the Sensor

   • Ensure the sensor is powered correctly (check VCC and GND connections).
   • Verify the I²C address (default is 0x40) and ensure no address conflicts on the bus.
   • Check the pull-up resistors on the SDA and SCL lines.

2. Inaccurate Readings

   • Ensure the sensor is not exposed to condensation or extreme environmental conditions.
   • Verify that the sensor is placed in an area with good airflow.
   • Check for noise in the power supply and add decoupling capacitors if necessary.

3. I²C Communication Errors

   • Confirm the SDA and SCL lines are connected to the correct pins on the microcontroller.
   • Check the I²C clock speed; the STS3032 supports standard (100kHz) and fast (400kHz) modes.

Q: Can the STS3032 measure both temperature and humidity simultaneously?
A: Yes, the sensor can measure both parameters, but you need to send separate commands for each measurement.

Q: What is the maximum cable length for I²C communication with the STS3032?
A: The maximum cable length depends on the pull-up resistor values and the I²C clock speed. For standard mode (100kHz), a length of up to 1 meter is typically reliable.

Q: Is the STS3032 waterproof?
A: No, the sensor is not waterproof. Avoid exposing it to water or condensation to maintain accuracy and longevity.

Q: Can I use the STS3032 with a 3.3V microcontroller?
A: Yes, the sensor operates within a voltage range of 3.3V to 5.5V, making it compatible with both 3.3V and 5V systems.