AM2103 Capacitive Digital Humidity And Temperature Sensor is a new high precision single bus temperature and humidity detector, which is based on AM2103 humidity capacitive digital temperature and humidity sensor chip. The AM2103 chip is a high quality, fast response, anti-interference, but a little expensive chip. This sensor is composed of a capacitive humid sensor to detect humidity in a wide range from zero up to 100% and a high precision temperature sensor in climate range from -40? up to +80?, which is connected to a high-performance 8-bit microcontroller. The humid and temperature sensor is calibrated in the clean room (laboratory), then calculates calibration coefficients and stored in the microcontroller program, to call it while sensing and during signal processing.