适用于霍尔电流传感器的温漂补偿电路设计

Design of temperature drift compensation circuit for Hall current sensor

霍尔电流传感器中存在的温漂会影响传感器的精度,特别是在极端高温和低温下影响更加明显,这限制了霍尔传感器应用的场合。针对该问题本文设计实现了一种适用于霍尔电流传感器的宽温度范围温漂补偿电路。温漂补偿电路通过将增益补偿与带隙补偿相结合,在霍尔电压放大电路中采用与霍尔元件形状材料均一致的负载电阻,补偿了霍尔元件的温漂误差;同时利用带隙基准电路产生的高低温补偿电流实现对放大器电路的尾电流的温度补偿,使得霍尔电流传感器可以在更宽的温度范围内保持灵敏度稳定。采用GF0.18μm BiCMOS工艺制程,仿真验证表明,在5 V电源电压下,电路在-40℃~140℃的宽温度范围内,灵敏度温漂误差小于0.3%,温漂系数达到35 ppm/℃。相较于其他温度补偿设计,该设计实现了对霍尔传感器高阶温度误差的补偿,使得霍尔传感器具有更宽的工作温度范围以及更小的温漂误差,且不需要额外的数字处理电路,具有较高的工程应用价值。

The temperature drift in Hall current sensors can affect the accuracy of the sensor,especially in extreme high and low temperatures,which limits the application of Hall sensors.This article designs and implements a wide temperature range temperature drift compensation circuit suitable for Hall current sensors to address this issue.The temperature drift compensation circuit compensates for the temperature drift error of the Hall element by combining gain compensation with bandgap compensation,and using a load resistor that is consistent with the shape and material of the Hall element in the Hall voltage amplification circuit.At the same time,using the high and low temperature compensation current generated by the bandgap reference circuit to achieve temperature compensation for the tail current of the amplifier circuit,the Hall current sensor can maintain sensitivity stability over a wider temperature range.Adopting GF0.18μm BiCMOS process,simulation verification shows that under a 5 V power supply voltage,the circuit has a wide temperature range of-40℃~140℃,a sensitivity temperature drift error of less than 0.3%,and a temperature drift coefficient of 35 ppm/℃.Compared to other temperature compensation designs,this design achieves compensation for high-order temperature errors of Hall sensors,resulting in a wider operating temperature range and smaller temperature drift errors.It does not require additional digital processing circuits and has high engineering application value.