Transcapacitive touch and force sensing in an input device

A processing system for force and proximity sensing at an input device, the processing system comprising:

• one or more processors;
• and
• a memory storing instructions that, when executed by the one or more processors, cause the processing system to be operable in at least a proximity sensing mode and a force sensing mode and:
• when operating in the proximity sensing mode:
• drive one or more touch transmitter electrodes with touch transmitter signals and determine a position of an input object within a sensing region based at least in part on touch resulting signals acquired from one or more touch receiver electrodes, wherein the sensing region is defined by the one or more touch transmitter electrodes and the one or more touch receiver electrodes;
• when operating in the force sensing mode:
• drive a plurality of force electrodes, disposed on a force electrode layer, with force transmitter signals, wherein the force electrode layer is separated from the touch transmitter electrodes and the touch receiver electrodes by a resilient material layer having an original shape;
• and
• determine a force of the input object based at least in part on force resulting signals acquired from at least one of the touch transmitter electrodes or the touch receiver electrodes based at least in part on a change in capacitance between the plurality of force electrodes and the at least one of the touch transmitter electrodes or the touch receiver electrodes wherein the resilient material layer is configured to deform from its original shape when a force is applied to the input device to cause the one or more of the touch transmitter electrodes or the touch receiver electrodes to deflect towards the force layer;
• determine a transcapacitive proximity measurement based on the touch resulting signals;
• and
• determine a transcapacitive force measurement from the force resulting signals.

A method of force and proximity sensing at an input device operable in at least a proximity sensing mode and a force sensing mode, the method comprising:

• when operating in the proximity sensing mode:
• driving one or more touch transmitter electrodes with touch transmitter signals and determining a position of an input object within a sensing region based at least in part on touch resulting signals acquired from one or more touch receiver electrodes, wherein the sensing region is defined by the one or more touch transmitter electrodes and the one or more touch receiver electrodes;
• when operating in the force sensing mode:
• driving a plurality of force electrodes, disposed on a force electrode layer, with force transmitter signals, wherein the force electrode layer is separated from the touch transmitter electrodes and the touch receiver electrodes by a resilient material layer having an original shape;
• and
• determining a force of the input object based at least in part on force resulting signals acquired from at least one of the touch transmitter electrodes or the touch receiver electrodes based at least in part on a change in capacitance between the plurality of force electrodes and the at least one of the touch transmitter electrodes or the touch receiver electrodes wherein the resilient material layer is configured to deform from its original shape when a force is applied to the input device to cause the one or more of the touch transmitter electrodes or the touch receiver electrodes to deflect towards the force layer;
• determining a transcapacitive proximity measurement based on the touch resulting signals;
• and
• determining a transcapacitive force measurement from the force resulting signals.