The SHT21 digital humidity and temperature sensor from Sensirion (Westlake Village, CA) is encapsulated in a 3 × 3 × 1.1 mm DFN 3-0 package. Over-molding provides protection against harsh environments. It is fully calibrated and provides an I2C digital interface. Analog output modes are available upon request. Typical sensor accuracy is ±2% RH over 20-80% RH and ±0.3°C over 25 to 42 °C. Provided on tape and reel, the reflow-solderable SHT21 is suitable for high-volume applications.