公开(公告)号：US20140327437A1

公开(公告)日：2014-11-06

申请号：US14368299

申请日：2012-10-30

Applicant: Jiangsu Multidimension Technology Co., Ltd.

Inventor： Liansheng Han ,  Jianmin Bai ,  Wei Li ,  Songsheng Xue

IPC: G01R19/00 ,  G01R33/06

CPC classification number: G01R19/0092 ,  G01R15/205 ,  G01R17/10 ,  G01R19/32 ,  G01R33/06 ,  G01R33/098

Abstract: This patent discloses a current sensor comprising a sensor bridge (14), which consists of several magnetic tunnel junction (MTJ) elements (R11, R12, R21, R22), a MTJ temperature compensation resistor (16), and a current lead (20), which are integrated onto the same chip. The current lead (20) is positioned close to the sensor bridge (14), and it is used to carry the test current (19). A permanent magnet (17) is arranged at the periphery of the MTJ temperature compensation resistor (16). The permanent magnet (17) rigidly aligns the magnetization direction (7) of the free layer of the MTJ temperature compensation resistor (16) anti-parallel to the magnetization direction (8) of a pinning layer; so that the MTJ temperature compensation resistor (16) remains in a high resistance state providing a resistance value that changes as a function of temperature. The sensor bridge (14) is connected in series with the MTJ temperature compensation resistor (16) in order to temperature compensate the sensor bridge (14). A magnetic field (21) generated by the test current (19) produces an output voltage at the output of the temperature compensated sensor bridge that is proportional to the test current value. As a result of this temperature compensated structure, the current sensor has the advantages of high sensitivity, wide linear range, low power consumption, and excellent temperature stability.

Abstract translation: 该专利公开了一种电流传感器，包括传感器桥（14），其由若干磁性隧道结（MTJ）元件（R11，R12，R21，R22），MTJ温度补偿电阻（16）和电流引线 ），它们集成到同一个芯片上。 电流引线（20）位于传感器桥（14）附近，用于承载测试电流（19）。 永磁体（17）布置在MTJ温度补偿电阻器（16）的外围。 永磁体（17）使与MTJ温度补偿电阻器（16）的自由层的磁化方向（7）刚性对准，该磁化方向与销钉层的磁化方向（8）反平行; 使得MTJ温度补偿电阻器（16）保持在高电阻状态，提供随温度变化的电阻值。 传感器桥（14）与MTJ温度补偿电阻（16）串联连接，以便对传感器桥（14）进行温度补偿。 由测试电流（19）产生的磁场（21）在温度补偿传感器桥的输出处产生与测试电流值成比例的输出电压。 作为该温度补偿结构的结果，电流传感器具有灵敏度高，线性范围宽，功耗低，温度稳定性优异的优点。