Tmr high-sensitivity single-chip push-pull bridge magnetic filed sensor

A TMR high-sensitivity single-chip push-pull bridge magnetic field sensor, comprising:

• a substrate;
• two comb-shaped soft ferromagnetic flux concentrators located on the substrate,
• wherein one comb-shaped soft ferromagnetic flux concentrator comprises a comb seat and N rectangular comb teeth with length×width being Lx×Ly, and the other comb-shaped soft ferromagnetic flux concentrator comprises a comb seat and N−1 rectangular comb teeth with length×width being Lx×Ly, N being an integer greater than 1;
• wherein the comb teeth of the two comb-shaped soft ferromagnetic flux concentrators are interdigitated to form an interdigitated structure;
• wherein gaps are formed between the comb teeth of one comb-shaped soft ferromagnetic flux concentrator and the comb seat of the other comb-shaped soft ferromagnetic flux concentrator in an X direction, and the length of the gap is Lgx;
• adjacent comb teeth form space gaps which are divided into 2m−1 odd space gaps and 2m even space gaps respectively formed in a +Y direction;
• and
• wherein the length of the space gap is Lsx, the width of the space gap is Lsy, and m is an integer greater than zero and less than N;
• and
• push magnetoresistive sensing element strings and pull magnetoresistive sensing element strings;
• wherein the push magnetoresistive sensing element strings and the pull magnetoresistive sensing element strings are located respectively in the odd space gaps and the even space gaps and are parallel to the X direction;
• wherein the push magnetoresistive sensing element strings are electrically interconnected into a push arm, the pull magnetoresistive sensing element strings are electrically interconnected into a pull arm, and the push arm and the pull arm are electrically interconnected into a push-pull magnetoresistive sensor bridge;
• wherein the push magnetoresistive sensing element string comprises multiple push magnetoresistive sensing elements, and the pull magnetoresistive sensing element string comprises multiple pull magnetoresistive sensing elements;
• wherein the magnetization alignment directions of the ferromagnetic pinned layers of the push magnetoresistive sensing elements and pull magnetoresistive sensing elements are +Y or −Y direction;
• and
• wherein a magnetic field gain coefficient ANS between the external magnetic field B(x-ext) in the X or −X direction and a By magnetic-field component in the gaps in the Y or −Y direction is given as to By/B(x-ext), and it is greater than 1.