Offset rejection electrodes

A Microelectromechanical System (MEMS) sensor comprising:

• a sensing element positioned on a surface forming a sensing reference plane;
• an anchor coupled to the surface;
• a proof mass coupled to the anchor, wherein the proof mass moves under an external excitation;
• wherein the sensing element comprises a first plurality of sensing elements coupled between the sensing reference plane and the proof mass to detect motion normal to the sensing reference plane and a second plurality of sensing elements coupled between the sensing reference plane and the proof mass to detect motion normal to the sensing reference plane,
• wherein the first plurality of sensing elements has partial symmetry with the second plurality of sensing elements based on polarities of sensing elements, areas of sensing elements, and distance of sensing elements to the anchor generates an offset that is substantially constant for curvature angles of the sensing reference plane that ranges between 0° to 360° degrees, wherein the offset that is substantially constant is greater than zero and is less than a maximum offset for a MEMS sensor with curvature angles of the sensing reference planes that ranges between 0° to 360° degrees with sensing elements that form a perfect symmetry based on polarities of its corresponding sensing elements, areas of its corresponding sensing elements, and distance of its corresponding sensing elements to the anchor;
• and
• a signal processing circuit configured to combine electrical charges generated by the first plurality of sensing elements and the second plurality of sensing elements to provide an output that is proportional to the external excitation.

A Microelectromechanical System (MEMS) sensor comprising:

• a first plurality of sensing elements positioned on a surface forming a sensing reference plane;
• an anchor coupled to the surface;
• a proof mass coupled to the anchor, wherein the proof mass moves under an external excitation;
• wherein the first plurality of sensing elements is configured to detect motion normal to the sensing reference plane;
• a signal processing circuit configured to combine electrical charges generated by the plurality of sensing elements to provide an output in response to the external excitation,
• wherein an axis line formed between the plurality of sensing elements is a straight line that goes through a center of the anchor, and wherein the axis line forms a first sensing elements section and a second sensing elements section from the plurality of sensing elements
• wherein placement, size, and shape associated with each sensing element of the first sensing elements section and the second sensing elements section forms a partial symmetry,
• wherein the partial symmetry between the first sensing elements section and the second sensing elements section is defined as a difference between a first function and a second function,
• wherein the first function results in a zero summation and wherein the second function results in a non-zero summation,
• wherein the first function is based on a product of polarity, area, and a first polynomial of a distance of each sensing element of the first sensing elements section to the axis line,
• wherein the second function is based on a product of polarity, area, and a second polynomial of a distance of each sensing element of the second sensing elements section to the axis line.