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SHT40-BD1B-R3

SENSHT40-BD1B-R3

Sensirion AG
Humidity, Temperature 0 ~ 100% RH I2C ±1.8% RH 4 s Surface Mount
Active13,394 in stock
Datasheet Digi-Key Compare Prices

Overview

The SHT40-BD1B-R3 is a high-accuracy digital humidity and temperature sensor from Sensirion SHT4x series. It provides calibrated 16-bit digital outputs over an I2C interface while maintaining extremely low power consumption and a wide supply voltage range from 1.08V to 3.6V. This sensor is housed in a compact 4-pin UDFN package measuring 1.5mm x 1.5mm x 0.5mm.

Why Choose This Part

The sensor features a high-performance integrated heater for self-decontamination in high-humidity environments. Its extremely low power profile, requiring only 0.4uA typical current for periodic measurements, makes it ideal for energy-harvesting applications. The wide 1.08V to 3.6V operating range simplifies power rail design by allowing direct connection to many lithium or alkaline batteries.

Applications

Battery-Powered IoT Nodes
Utilizes the 80nA idle current and 1.08V minimum supply voltage to maximize battery life in remote wireless sensors.
HVAC Systems
Provides reliable climate monitoring with +/-1.8% RH accuracy for energy-efficient building automation.
Industrial Cold Chain
Operates across a wide -40C to 125C range to monitor temperature-sensitive pharmaceutical or food transport.
Wearable Electronics
The ultra-small 1.5mm footprint and low profile allow for integration into space-constrained health monitoring devices.

Key Specifications

Output 16b
Accuracy +/-1.8% RH
Output Type I2C
Sensor Type Humidity, Temperature
Mounting Type Surface Mount
Response Time 4 s
Humidity Range 0 ~ 100% RH
Package / Case 4-UDFN Exposed Pad
Voltage - Supply 1.08V ~ 3.6V
Operating Temperature -40degC ~ 125degC
Supplier Device Package 4-DFN (1.5x1.5)

Getting Started

Engineers can evaluate this sensor using the Sensirion SEK-SHT4x evaluation kit or by connecting it to an I2C bus on an MCU like an ESP32 or STM32. Sensirion provides comprehensive C drivers on GitHub that handle CRC checking and the sensor's specific measurement commands. Ensure the exposed pad is soldered to a floating plane or GND as per the datasheet to maintain thermal performance.

SHT40 Family

Comparing specs that differ across variants. The current part is highlighted.

Part Number Package Stock
SHT40-BD1B-R3 (this part) UDFN-4 13,394
SHT40-AD1F-R2 WDFN-4 20,597
SHT40-AD1B-R2 (Sensirion) WDFN-4 13,387
SHT40-AD1B-R3 (Sensirion) WDFN-4 59,057

Also Consider

SHT31-DIS-B SENSensirion AG - A more established industry standard with a slightly different package size and I2C addressing scheme.
HDC2010 TITexas Instruments - An alternative ultra-low power humidity sensor with a WLCSP package for even smaller footprints.
BME280 Bosch Sensortec - Integrated pressure, humidity, and temperature sensing in a single package for environmental monitoring.
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