How much does temperature change affect Hall effect sensors?

1. Change in sensitivity
Temperature changes can cause changes in the sensitivity of Hall effect sensors. As temperature increases, the sensitivity of Hall sensors generally decreases. This is because when the temperature increases, the mobility of carriers decreases, resulting in a decrease in the absolute value of the Hall potential. For example, at 10°C, the sensitivity of the Hall sensor is 1.12 V/mm, while at 28°C, the sensitivity decreases to 0.81 V/mm.
2. Zero drift
Temperature changes can cause zero drift in the Hall sensor, resulting in an overall shift in the output value. This drift can affect the measurement accuracy of the sensor, especially in applications with high precision requirements.
3. Linearity changes
Temperature changes can also affect the linearity of the Hall sensor. At different temperatures, the output characteristic curve of the Hall sensor may change, resulting in poor linearity. For example, at 10°C, the linearity of the Hall sensor is 7.27%, while at 28°C, the linearity decreases to 9.94%.
4. The importance of temperature compensation
Temperature compensation is usually required to reduce the impact of temperature changes on the performance of Hall effect sensors. Temperature compensation can be achieved through the following methods:
Constant current source compensation: Using a constant current source to supply power can reduce the temperature influence of the input end, because the constant current source can stably control the current and reduce the influence of input resistance changing with temperature.
Synchronous compensation of input and output ends: The synchronous compensation of input and output ends can further improve the temperature characteristics of the sensor and improve its environmental adaptability.
Neural network compensation: Using the chaotic adaptive whale optimized BP neural network (CIWOA-BP) for temperature compensation can significantly improve the measurement accuracy and stability of the sensor. The research results show that after temperature compensation, the sensitivity temperature coefficient αs of the Hall effect force sensor is reduced from 5.08×10^-3/℃ to 9.8×10^-5/℃, which is reduced by 2 orders of magnitude, and the temperature additional relative error is reduced from 19.82% before compensation to 0.38%, which is reduced by more than 52 times.