Si7021-A20 I2C Humidity and Temperature Sensor
The Si7021 I2C Humidity and Temperature Sensor is a monolithic CMOS IC designed for accurate environmental monitoring. It integrates humidity and temperature sensor elements, an analog-to-digital converter, signal processing, and calibration data, all accessible via an I2C interface. Leveraging patented low-K polymeric dielectrics for humidity sensing, it offers low power consumption, minimal drift and hysteresis, and excellent long-term stability. The sensor is factory-calibrated and fully interchangeable, requiring no recalibration or software changes. Available in a 3x3 mm DFN package, it serves as a drop-in upgrade for existing sensors, providing precision sensing over a wider range with reduced power usage. An optional factory-installed cover offers protection from liquids and particulates. The Si7021 is ideal for applications such as HVAC/R, thermostats, respiratory therapy, white goods, indoor weather stations, micro-environments, automotive climate control, asset tracking, and mobile devices.
Product Attributes
- Brand: Silicon Laboratories
- Model: Si7021-A20
- Material: Monolithic CMOS IC
- Package: 3x3 mm DFN
- Certifications: Patent Protected
Technical Specifications
| Parameter | Symbol | Test Condition | Min | Typ | Max | Unit |
| General Specifications | ||||||
| Power Supply | VDD | 1.9 | 3.6 | V | ||
| Operating Temperature (I and Y grade) | TA | 40 | +125 | C | ||
| Operating Temperature (G grade) | TA | 40 | +85 | C | ||
| Input Voltage High | VIH | SCL, SDA pins | 0.7xVDD | V | ||
| Input Voltage Low | VIL | SCL, SDA pins | 0.3xVDD | V | ||
| Input Voltage Range | VIN | SCL, SDA pins with respect to GND | 0.0 | VDD | V | |
| Input Leakage | IIL | SCL, SDA pins | 1 | A | ||
| Output Voltage Low | VOL | SDA pin; IOL = 2.5 mA; VDD = 3.3 V | 0.6 | V | ||
| Output Voltage Low | VOL | SDA pin; IOL = 1.2 mA; VDD = 1.9 V | 0.4 | V | ||
| Current Consumption (RH conversion) | IDD | 150 | 180 | A | ||
| Current Consumption (Temp conversion) | IDD | 90 | 120 | A | ||
| Current Consumption (Standby, 40 to +85 C) | IDD | No conversion or I2C transaction | 0.06 | 0.62 | A | |
| Current Consumption (Standby, 40 to +125 C) | IDD | No conversion or I2C transaction | 0.06 | 3.8 | A | |
| Peak Current (Powerup) | IDD | 3.5 | 4.0 | mA | ||
| Peak Current (I2C operations) | IDD | 3.5 | 4.0 | mA | ||
| Heater Current | IHEAT | HTRE bit enabled | 3.1 to 94.2 | mA | ||
| Conversion Time (12-bit RH) | tCONV | 10 | 12 | ms | ||
| Conversion Time (11-bit RH) | tCONV | 5.8 | 7 | ms | ||
| Conversion Time (10-bit RH) | tCONV | 3.7 | 4.5 | ms | ||
| Conversion Time (8-bit RH) | tCONV | 2.6 | 3.1 | ms | ||
| Conversion Time (14-bit temperature) | tCONV | 7 | 10.8 | ms | ||
| Conversion Time (13-bit temperature) | tCONV | 4 | 6.2 | ms | ||
| Conversion Time (12-bit temperature) | tCONV | 2.4 | 3.8 | ms | ||
| Conversion Time (11-bit temperature) | tCONV | 1.5 | 2.4 | ms | ||
| Powerup Time | tPU | VDD 1.9 V to ready for conversion, 25 C | 18 | 25 | ms | |
| Powerup Time | tPU | VDD 1.9 V to ready for conversion, full temperature range | 80 | ms | ||
| Powerup Time | tPU | After software reset command | 5 | 15 | ms | |
| I2C Interface Specifications | ||||||
| Hysteresis | VHYS | High-to-low vs low-to-high transition | 0.05 x VDD | V | ||
| SCLK Frequency | fSCL | 400 | kHz | |||
| SCL High Time | tSKH | 0.6 | s | |||
| SCL Low Time | tSKL | 1.3 | s | |||
| Start Hold Time | tSTH | 0.6 | s | |||
| Start Setup Time | tSTS | 0.6 | s | |||
2411041634_SILICON-LABS-SI7021-A20-IM1R_C2836034.pdf
Please Use Our Online Inquiry Contact Form Below If You Have Any Questions, Our Team Will Get Back To You As Soon As Possible
