Overview
The HTS221TR from STMicroelectronics is an ultracompact sensor designed for measuring relative humidity and temperature. Although it is currently in the process of being terminated and not recommended for new designs, it remains a significant component in existing systems. The HTS221 includes a sensing element and a mixed signal ASIC, providing measurement information through digital serial interfaces. The sensing element is a polymer dielectric planar capacitor structure, manufactured using a dedicated ST process, capable of detecting relative humidity variations. The sensor is available in a small top-holed cap land grid array (HLGA) package and operates over a temperature range from -40 °C to +120 °C.
Key Specifications
| Parameter | Specification |
|---|---|
| Relative Humidity Range | 0 to 100% |
| Supply Voltage | 1.7 to 3.6 V |
| Power Consumption | 2 µA @ 1 Hz ODR |
| Output Data Rate (ODR) | Selectable from 1 Hz to 12.5 Hz |
| Humidity Sensitivity | 0.004% rH/LSB |
| Humidity Accuracy | ± 3.5% rH, 20 to +80% rH |
| Temperature Accuracy | ± 0.5 °C, 15 to +40 °C |
| ADC Resolution | 16-bit |
| Output Data Format | 16-bit humidity and temperature output data |
| Interfaces | SPI and I²C |
| Calibration | Factory calibrated |
| Package Dimensions | 2 x 2 x 0.9 mm |
| Environmental Compliance | ECOPACK compliant |
Key Features
- Ultracompact design in a 2 x 2 x 0.9 mm HLGA package
- High relative humidity sensitivity: 0.004% rH/LSB
- Low power consumption: 2 µA @ 1 Hz ODR
- Selectable output data rate from 1 Hz to 12.5 Hz
- Embedded 16-bit ADC for precise measurements
- 16-bit humidity and temperature output data
- SPI and I²C digital serial interfaces
- Factory calibrated for accuracy
- Operates over a wide temperature range: -40 °C to +120 °C
- ECOPACK compliant for environmental sustainability
Applications
- Air conditioning, heating, and ventilation systems
- Air humidifiers
- Refrigerators
- Wearable devices
- Smart home automation
- Industrial automation
- Respiratory equipment
- Asset and goods tracking
Q & A
- What is the relative humidity range of the HTS221TR?
The HTS221TR measures relative humidity from 0 to 100%.
- What is the supply voltage range for the HTS221TR?
The supply voltage range is from 1.7 to 3.6 V.
- What are the available output data rates for the HTS221TR?
The output data rate is selectable from 1 Hz to 12.5 Hz.
- What is the humidity accuracy of the HTS221TR?
The humidity accuracy is ± 3.5% rH, 20 to +80% rH.
- What is the temperature accuracy of the HTS221TR?
The temperature accuracy is ± 0.5 °C, 15 to +40 °C.
- Does the HTS221TR support multiple communication interfaces?
- Is the HTS221TR factory calibrated?
- What is the package size of the HTS221TR?
The package dimensions are 2 x 2 x 0.9 mm.
- Is the HTS221TR environmentally compliant?
- Why is the HTS221TR not recommended for new designs?
The HTS221TR is in the process of being terminated, and STMicroelectronics recommends using the SHT40-AD1B from Sensirion as a replacement.
