5.3.2 Standard Electrode Design
The MGC3140 electrode system is typically a double-layer design with a Tx transmit electrode at the bottom layer to shield against device ground and, thus, ensure high-receive sensitivity. Up to five comparably smaller Rx electrodes are placed above the Tx layer providing the spatial resolution of the GestIC system. Tx and Rx are separated by a thin isolating layer. The Rx electrodes are typically arranged in a frame configuration as shown in the figure below.
The frame defines the inside sensing area.
Larger dimensions yield in higher sensitivity of the system.
For more information on sensor design as well as the function of the center electrode, see "GestIC Design Guide" (DS40001716).
The electrode shapes can be designed solid or structured. In addition to the distance and the material between the Rx and Tx electrodes, the shape structure density also controls the capacitance CRxTx and thus, the sensitivity of the system.