Product Overview
The Si7021 I2C Humidity and Temperature Sensor is a monolithic CMOS IC that integrates humidity and temperature sensor elements, an analog-to-digital converter, signal processing, calibration data, and an I2C Interface. It is factory-calibrated for interchangeability and features low-power, monolithic CMOS sensor ICs with low drift and hysteresis, and excellent long-term stability. Available in a 3x3 mm DFN package, it offers a drop-in upgrade for existing RH/temperature sensors with precision sensing over a wider range and lower power consumption. The optional factory-installed cover protects the sensor from liquids and particulates. This sensor is ideal for measuring humidity, dew-point, and temperature in various applications including HVAC/R, thermostats, respiratory therapy, white goods, indoor weather stations, micro-environments/data centers, automotive climate control, asset tracking, and mobile devices.
Product Attributes
- Brand: Silicon Laboratories
- Model: Si7021-A20
- Package: 3x3 mm DFN
- Optional Feature: Factory-installed protective cover
- Certifications: Patent Protected
Technical Specifications
| Parameter | Symbol | Test Condition | Min | Typ | Max | Unit |
| 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 (SCL, SDA) | VIH | 0.7xVDD | V | |||
| Input Voltage Low (SCL, SDA) | VIL | 0.3xVDD | V | |||
| Input Voltage Range (SCL, SDA) | VIN | with respect to GND | 0.0 | VDD | V | |
| Input Leakage (SCL, SDA) | IIL | 1 | A | |||
| Output Voltage Low (SDA) | VOL | IOL = 2.5 mA; VDD = 3.3 V | 0.6 | V | ||
| Output Voltage Low (SDA) | VOL | 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 Consumption (powerup) | IDD | 3.5 | 4.0 | mA | ||
| Peak Current Consumption (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 (VDD 1.9 V to ready, 25 C) | tPU | 18 | 25 | ms | ||
| Powerup Time (VDD 1.9 V to ready, full temp range) | tPU | 80 | ms | |||
| Powerup Time (after software reset) | tPU | 5 | 15 | ms | ||
| 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 |
2411261532_SILICON-LABS-SI7021-A20-GM1R_C132603.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
