7Semi SHT2x Arduino Library

Arduino driver for the Sensirion SHT2x series temperature and humidity sensors (SHT20, SHT21, SHT25).

The SHT2x sensors provide accurate relative humidity and temperature measurements with low power consumption and digital I²C interface, making them ideal for environmental monitoring applications.

Features

• Full SHT2x command support

• Temperature measurement (°C)

• Relative humidity measurement (%RH)

• Configurable resolution

• Heater control

• CRC validation for data integrity

• Serial number reading

• Low power operation

---

Connections / Wiring

The SHT2x communicates using I²C interface.

I²C Connection

SHT2x Pin	MCU Pin	Notes
VCC	3.3V	3.3V only
GND	GND	Common ground
SDA	SDA	I²C data
SCL	SCL	I²C clock

---

I²C Notes

• Default I²C address: 0x40

• Supported bus speeds:

  • 100 kHz
  • 400 kHz (recommended)

---

Installation

• Arduino Library Manager

  1. Open Arduino IDE
  2. Go to Library Manager
  3. Search for 7Semi SHT2x
  4. Click Install

• Manual Installation

  1. Download this repository as ZIP
  2. Arduino IDE → Sketch → Include Library → Add .ZIP Library

---

Library Overview

Reading Temperature

float temperature;

sensor.readTemperature(temperature);

• Returns temperature in °C

Combined Reading

float temperature, humidity;

sensor.readTempHum(temperature, humidity);

• Reads both temperature and humidity

Reads both temperature and humidity

The SHT2x allows adjusting measurement resolution:

sensor.setResolution(SHT2x_RES_12_14);

Heater Control

Enable or disable internal heater:

sensor.setHeater(true);

• Useful for condensation removal

Reading Serial Number

uint64_t serial;

sensor.readSerialNumber(serial);

• Returns unique device ID

Soft Reset

sensor.softReset();

• Resets sensor to default state