A single-chip differential free layer push-pull magnetic field sensor bridge, comprising: a substrate on an X-Y plane; a soft magnetic flux concentrator array, wherein each soft magnetic flux concentrator has sides parallel to an X-axis and a Y-axis, extends by Lx in the X-axis direction and Ly in the Y-axis direction, and has four corners sequentially labeled as A, B, C and D clockwise from an upper left position; and a magnetoresistive sensing unit array on the substrate, comprising a plurality of magnetoresistive sensing units (31, 32, 33, 34); wherein the magnetoresistive sensing units (31, 33) near the A and C corner positions of the soft magnetic flux concentrators are referred to as push magnetoresistive sensing units; the magnetoresistive sensing units (32, 34) near the B and D corner positions of the soft magnetic flux concentrators are referred to as pull magnetoresistive sensing units; all the push magnetoresistive sensing units are electrically interconnected into one or more push arms; all the pull magnetoresistive sensing units are electrically interconnected into one or more pull arms; and all the push arms and all the pull arms are electrically interconnected to form a push-pull sensor bridge; characterized in that the soft magnetic flux concentrator array comprises first and second sub-arrays (11, 12), each sub-array comprising a plurality of columns parallel to the Y-axis direction and a plurality of rows parallel to the X-axis direction, each column comprising a plurality of soft magnetic flux concentrators, wherein the columns of the first and second sub-arrays are located in an alternating arrangement along the X-axis direction, the rows of each sub-array are spaced apart by ygap, and wherein the rows of the second sub-array are offset in the Y-axis direction from the rows of the first sub-array by (Ly + ygap)/2; and wherein each magnetoresistive sensing unit is located in a gap between a soft magnetic flux concentrator of the first sub-array and an adjacent soft magnetic flux concentrator of the second sub-array. a substrate on an X-Y plane; a soft magnetic flux concentrator array, wherein each soft magnetic flux concentrator has sides parallel to an X-axis and a Y-axis, extends by Lx in the X-axis direction and Ly in the Y-axis direction, and has four corners sequentially labeled as A, B, C and D clockwise from an upper left position; and a magnetoresistive sensing unit array on the substrate, comprising a plurality of magnetoresistive sensing units (31, 32, 33, 34); wherein the magnetoresistive sensing units (31, 33) near the A and C corner positions of the soft magnetic flux concentrators are referred to as push magnetoresistive sensing units; the magnetoresistive sensing units (32, 34) near the B and D corner positions of the soft magnetic flux concentrators are referred to as pull magnetoresistive sensing units; all the push magnetoresistive sensing units are electrically interconnected into one or more push arms; all the pull magnetoresistive sensing units are electrically interconnected into one or more pull arms; and all the push arms and all the pull arms are electrically interconnected to form a push-pull sensor bridge; characterized in that the soft magnetic flux concentrator array comprises first and second sub-arrays (11, 12), each sub-array comprising a plurality of columns parallel to the Y-axis direction and a plurality of rows parallel to the X-axis direction, each column comprising a plurality of soft magnetic flux concentrators, wherein the columns of the first and second sub-arrays are located in an alternating arrangement along the X-axis direction, the rows of each sub-array are spaced apart by ygap, and wherein the rows of the second sub-array are offset in the Y-axis direction from the rows of the first sub-array by (Ly + ygap)/2; and wherein each magnetoresistive sensing unit is located in a gap between a soft magnetic flux concentrator of the first sub-array and an adjacent soft magnetic flux concentrator of the second sub-array.