Abstract:When the temperature environment of the MEMS accelerometer changes drastically, the measurement accuracy is greatly affected, resulting in drift errors, and it is difficult to meet the needs of high-precision navigation. Therefore, it is urgent to design a constant temperature circuit to make the accelerometer work in a stable long-term In the working environment, study the working state of the accelerometer under constant temperature. For the requirement of constant temperature control, Aiming at the requirement of constant temperature control, a constant temperature control circuit based on DSP2812 is designed. The sensor is surrounded by heating circuit and insulation layer to reduce heat dissipation, a software control system based on DSP and high-precision digital temperature sensor TMP116 is presented. The PID control is deeply studied and a new control method is proposed. The experiment outputs PWM duty cycle, control temperature and detection temperature data, after experimental testing, at -40°C working environment, the system overshoot is 1% after PID control, and the temperature rises from 57°C to 70°C within two minutes and stabilizes. After stabilization, the temperature can be accurately controlled at 70±0.06℃, which can effectively maintain the system constant temperature.