Patent attributes
In one embodiment, a system includes a touch sensor, measurement circuits, and a monitoring circuit. The measurement circuits are respectively coupled to electrodes of the touch sensor. Each measurement circuit includes a first component, a second component, and a third component. The first component of each measurement circuit is activated in a first power mode and the second and third components of each measurement circuit are deactivated in the first power mode. The monitoring circuit is coupled to the measurement circuits and includes a first component, a second component, and a third component. The monitoring circuit is configured to perform operations in the first power mode. The operations include receiving signals from the measurement circuits and generating an output signal that is proportional to a sum of the signals received from the measurement circuits. A value of the generated output signal indicates whether activity has occurred on the touch sensor.