New Digital Thermostat Development

A new digital thermostat with features as Microcontroller unit-based, programmable, friendly-user interface, ultra-low power consumption, and "Green" has been developed. The design of hardware and software are discussed in detail in this paper. The hardware includes power supply circuit, MCU-based control circuit, voltage divider circuit and LCD display circuit, Software design is innovative as well, which includes temperature and humidity measurement and calibration algorithm, thermistor compensation algorithm, PWM signal modulation algorithm and PID algorithm so on. The purpose of digital thermostat research is to reduce power consumption and accomplish automatic fail-safe protection. In addition, cost analysis, bill of material, compliance tests are simply introduced to qualify the product design. Because of its pb-free electronic components and mechanical parts, plus power saving, the digital thermostat is a "Green" product, its performance and reliability are guaranteed by comprehensive hardware and software consideration. Therefore, the digital thermostat development will benefit to sustainable and green product development.