SHT21
NRND±2% Digital humidity and temperature sensor
The digital SHT2x humidity sensor series is used in high volumes in a wide variety of applications and has today become the de facto industry standard. The SHT2x series consists of a low-cost version with the SHT20 humidity sensor, a standard version with the SHT21 humidity sensor, and a high-end version with the SHT25 humidity sensor. The open cavity mold package - which encapsulates the complete chip except for the humidity sensor area - protects the capacitive humidity sensor against external impact and facilitates excellent long-term stability. The SHT2x sensors are available both in large and small volumes. Embedded in a reflow solderable dual-flat no-leads (DFN) package of 3 × 3 × 1.1 mm³, the SHT2x provides calibrated, linearized sensor signals in digital, I²C format. The SHT2x humidity sensor series contains a capacitive-type humidity sensor, a band-gap temperature sensor, and specialized analog and digital integrated circuits – all on a single CMOSens® chip. This yields superior sensor performance in terms of accuracy and stability as well as minimal power consumption. Every sensor is individually calibrated and tested. Lot identification is printed on the sensor and an electronic identification code is stored on the chip – which can be read out on command. Furthermore, the resolution of the SHT2x humidity sensor can be changed on command (8/12 bit up to 12/14 bit for RH/T) and a checksum helps to improve communication reliability. With this set of features and its proven reliability and long-term stability, the SHT2x humidity sensor series offers an outstanding price-performance ratio. To test a humidity sensor from the SHT2x series, two evaluation kits, EK-H4 and EK-H5, are available.
Successor product
| Name | Description | Series | Category |
|---|---|---|---|
 SHT41 | ±1.8% / max. ±2.5% RH Digital humidity and temperature sensor | SHT4x | Humidity |
Specification
| Humidity | |||
|---|---|---|---|
| Typ. relative humidity accuracy
2
| 2 | %RH | |
| Operating relative humidity range
0 - 100
| 0 - 100 | %RH | |
| Response time (τ63%)
8
| 8 | s | |
| Calibration certificate
Factory calibration
| Factory calibration |
| Temperature | |||
|---|---|---|---|
| Typ. temperature accuracy
0.3
| 0.3 | °C | |
| Operating temperature range [°C]
-40 - 125
| -40 - 125 | °C | |
| Response time (τ63%)
5
| 5 | s |
| Generic | |||
|---|---|---|---|
| Supply voltage
2.1 - 3.6
| 2.1 - 3.6 | V | |
| Average supply current
300
| 300 | uA | |
| Max. supply current
330
| 330 | uA | |
| Interfaces
I²C
| I²C | ||
| Size (LxWxH)
3 x 3 x 1.1
| 3 x 3 x 1.1 | mm³ | |
| Packaging size
400, 1500, 5000
| 400, 1500, 5000 | pcs (T&R) |
Downloads
Accessories
| Name | Description | Series | Category |
|---|---|---|---|
 SF2 filter cap | Filter cap for SHT2x to SHT4x humidity and temperature sensors | SFx filter cap | Humidity |
Latest Humidity sensors
SHT40I-BD1B
±2% Digital humidity and temperature sensor / 0x45 I2C Output
- Sensor
- Humidity
SHT40-CD1B
±1.8% / max. ±3.5% RH Digital humidity & temp. sensor / 0x46 I2C Output
- Sensor
- Humidity
SHT40-BD1B
±1.8% / max. ±3.5% RH Digital humidity & temp. sensor / 0x45 I2C Output
- Sensor
- Humidity
SHT41A-BD1B
±2% humidity sensor for automotive applications / I2C interface
- Sensor
- Humidity
SHT41A-FD1B
±2% humidity sensor for automotive applications / PWM interface
- Sensor
- Humidity
SHT43
Digital humidity sensor with ISO17025 certification
- Sensor
- Humidity
SEK-SHT40-AD1F
Evaluation kit for SHT40 humidity sensor with filter membrane
- Evaluation kit
- Humidity
Smart sensors for your application
Sensirion's sensor solutions are used in a wide range of applications and markets. Our reliable environmental and flow sensors improve energy efficiency, increase health and ensure safety and comfort.