Silicon Laboratories Inc.
Shielding in a unit capacitor array

Abstract:

An array of capacitors on an integrated circuit includes a plurality of unit capacitors. Each unit capacitor includes an isolated capacitor node formed in a pillar structure. Each unit capacitor further includes a shared capacitor adjacent to the isolated capacitor node. The shared capacitor node is electrically coupled to shared capacitor nodes of other unit capacitors in the array. Each unit capacitor further includes a shield node coupled to a low impedance node and formed adjacent to the isolated capacitor node to reduce the chance of capacitance forming between conductors to the isolated nodes and the shared nodes thereby preventing unwanted charge from entering the shared nodes and reducing linearity of the array.