The **SHT41-AD1B-R3** is a high-precision digital sensor designed by Sensirion. It is part of the fourth-generation (SHT4x) series, specifically engineered for measuring relative humidity and temperature with ultra-low power consumption in a miniature form factor. --- ### 1. Key Technical Specifications | Parameter | Specification | | :--- | :--- | | **Interface** | I2C (Standard, Fast Mode Plus) | | **Supply Voltage (VDD)** | 1.08 V to 3.6 V | | **Average Current** | 0.4 µA (at 1 Hz sample rate) | | **Idle Current** | 80 nA | | **Temperature Range** | -40°C to +125°C | | **Humidity Range** | 0% to 100% RH | | **Package Type** | 4-pin DFN (1.5 x 1.5 x 0.5 mm) | --- ### 2. Sensor Performance Accuracy The SHT41 version offers improved accuracy over the standard SHT40 model. * **Relative Humidity Accuracy:** Typical accuracy of **±2% RH** (from 0 to 100% RH). * **Temperature Accuracy:** Typical accuracy of **±0.2°C** (from 0 to 75°C). --- ### 3. Core Features and Components * **Integrated Heater:** The chip includes an internal power-programmable heater. This is used to remove condensed water from the sensor surface or to prevent "creep" in high-humidity environments. * **Fully Calibrated Digital Output:** The sensor provides linearized, compensation-free digital signals via the I2C protocol. * **I2C Address:** The "AD1B" suffix specifically refers to the I2C address. The standard address for this specific part is **0x44**. * **NIST Traceability:** The sensor is factory-calibrated and the calibration is traceable to NIST (National Institute of Standards and Technology). --- ### 4. Pin Configuration (DFN-4) | Pin # | Name | Description | | :--- | :--- | :--- | | 1 | **SCL** | I2C Serial Clock input | | 2 | **VSS** | Ground | | 3 | **SDA** | I2C Serial Data I/O | | 4 | **VDD** | Supply Voltage | --- ### 5. Application Circuit Example To integrate the SHT41, you typically only need two pull-up resistors for the I2C lines and one decoupling capacitor for power stability. ```cpp // Typical I2C connection logic // VDD -> 100nF Capacitor -> GND // SDA -> 4.7k Ohm Resistor -> VDD // SCL -> 4.7k Ohm Resistor -> VDD ``` --- ### 6. Typical Applications * **Mobile Devices:** Due to the extremely low power draw (smartphones, wearables). * **HVAC Systems:** For climate monitoring and control. * **Medical Equipment:** Respiratory devices and incubators. * **Logistics:** Cold chain monitoring and smart packaging. ---