Capacitive sensor coupling correction

A touch sensor apparatus having a touch sensor panel, the apparatus adapted to normalize the effects of parasitic coupling in the touch sensor panel, the apparatus comprising:

• a drive structure comprises one of a plurality of drive lines on the touch sensor panel, each drive line comprising a plurality of drive line conductive elements, the drive line conductive elements being coupled together by a plurality of connecting traces, the connecting traces extend parallel to a plurality of sense lines and disposed between the plurality of sense lines and the plurality of drive line conductive elements
• one or more of the plurality of sense lines on the touch sensor panel, each sense line comprising at least one sense line conductive element, the plurality of sense lines being disposed transverse to the plurality of drive lines;
• a first module adapted to stimulate a set of drive lines of the plurality of drive lines;
• a second module adapted to sense at least one sense signal on at least one of the plurality of sense lines for each drive line stimulated;
• and
• a third module adapted to correct the magnitude of the at least one sense signal by utilizing a set of correctional coefficients, wherein at least one correctional coefficient depends upon an expected signal and a set of sensed signals;
• and
• wherein the set of sensed signals is determined after positioning a conductive element proximate to a sensing portion of the touch sensor panel.

A mobile phone comprising a touch sensor panel, the mobile phone adapted to normalize the effects of parasitic coupling, the mobile phone comprising:

• a drive structure comprises one of a plurality of drive lines on the touch sensor panel, each drive line comprising a plurality of drive line conductive elements, the drive line conductive elements being coupled together by a plurality of connecting traces, the connecting traces extend parallel to a plurality of sense lines and disposed between the plurality of sense lines and the plurality of drive line conductive elements
• one or more of the plurality of sense lines on the touch sensor panel, each sense line comprising at least one sense line conductive element, the plurality of sense lines being disposed transverse to the plurality of drive lines;
• a first module adapted to stimulate a set of drive lines of the plurality of drive lines;
• a second module adapted to sense at least one sense signal on at least one of the plurality of sense lines for each drive lines stimulated;
• and
• a third module adapted to correct the magnitude of a signal by utilizing a set of correctional coefficients, wherein at least one correctional coefficient depends upon an expected signal and a set of sensed signal;
• and
• wherein the set of sensed signals is determined after positioning a conductive element proximate to a sensing portion of the touch sensor panel.

A digital media player comprising a touch sensor panel, the digital media player adapted to normalize the effects of parasitic coupling, the digital media player comprising:

• a drive structure comprises one of a plurality of drive lines on the touch sensor panel, each drive line comprising a plurality of drive line conductive elements, the drive line conductive elements being coupled together by a plurality of connecting traces, the connecting traces extend parallel to a plurality of sense lines and disposed between the plurality of sense lines and the plurality of drive line conductive elements
• one or more of the plurality of sense lines on the touch sensor panel, each sense line comprising at least one sense line conductive element, the plurality of sense lines being disposed transverse to the plurality of drive lines;
• a first module adapted to stimulate a set of drive lines of the plurality of drive lines;
• a second module adapted to sense at least one sense signal on at least one of the plurality of sense lines for each drive lines stimulated;
• and
• a third module adapted to correct the magnitude of a signal by utilizing a set of correctional coefficients, wherein at least one correctional coefficient depends upon an expected signal and a set of sensed signals;
• and
• wherein the set of sensed signals is determined after positioning a conductive element proximate to a sensing portion of the touch sensor panel.

A personal computer comprising a touch sensor panel, the personal computer adapted to normalize the effects of parasitic coupling, the personal computer comprising:

• a drive structure comprises one of a plurality of drive lines on the touch sensor panel, each drive line comprising a plurality of drive line conductive elements, the drive line conductive elements being coupled together by a plurality of connecting traces, the connecting traces extend parallel to a plurality of sense lines and disposed between the plurality of sense lines and the plurality of drive line conductive elements
• one or more of the plurality of sense lines on the touch sensor panel, each sense line comprising at least one sense line conductive element, the plurality of sense lines being disposed transverse to the plurality of drive lines;
• a first module adapted to stimulate a set of drive lines of the plurality of drive lines;
• a second module adapted to sense at least one sense signal on at least one of the plurality of sense lines for each drive structure stimulated;
• and
• a third module adapted to correct the magnitude of the at least one sense signal by utilizing a set of correctional coefficients, wherein at least one correctional coefficient depends upon an expected signal and a set of sensed signals;
• and
• wherein the set of sensed signals is determined after positioning a conductive element proximate to a sensing portion of the touch sensor panel.

A method of normalizing the effects of parasitic coupling in a touch sensor panel, the method comprising:

• stimulating a drive structure;
• detecting a signal at a sense structure in response to stimulating the drive structure;
• and
• correcting the signal by utilizing a set of correctional coefficients, wherein the set of correctional coefficients is based at least in part upon a set of previously sensed signals,
• wherein the set of previously sensed signals is determined by a process comprising:
• completely covering the touch sensor panel with a conductive element;
• stimulating a plurality of drive structures;
• and
• sensing a signal for each drive structure stimulated.

A method of normalizing the effects of parasitic coupling in a touch sensor panel, the method comprising:

• stimulating a drive structure;
• detecting a signal at a sense structure in response to stimulating the drive structure;
• and
• correcting the signal by utilizing a set of correctional coefficients, wherein the set of correctional coefficients is based at least in part upon a set of previously sensed signals
• wherein the set of previously sensed signals is determined by a process comprising:
• completely covering a conductive element upon the touch sensor panel;
• stimulating a plurality of drive structures;
• and
• sensing a signal for each drive structure stimulated.

An apparatus adapted to normalize the effects of parasitic coupling, the apparatus comprising:

• a memory unit adapted to store data;
• a first module adapted to stimulate a set of drive structures;
• a second module adapted to sense a signal for each drive structure stimulated;
• and
• a third module adapted to correct a signal by utilizing a set of correctional coefficients, wherein at least one correctional coefficient depends upon an expected signal and a set of sensed signals;
• wherein:
• the set of correctional coefficients is adapted to correct for changes to parasitic capacitive coupling associated with one or more connecting traces coupled to the set of drive structures;
• and
• the expected signal is set to be equal to a first sensed signal;
• and
• wherein the first sensed signal is obtained from a drive structure having a shorter connecting trace than any other drive structure of the set of drive structures.

An apparatus adapted to normalize the effects of parasitic coupling, the apparatus comprising:

• a memory unit adapted to store data;
• a first module adapted to stimulate a set of drive structures;
• a second module adapted to sense a signal for each drive structure stimulated;
• and
• a third module adapted to correct a signal by utilizing a set of correctional coefficients, wherein at least one correctional coefficient depends upon an expected signal and a set of sensed signals;
• wherein:
• the set of correctional coefficients is adapted to correct for changes to parasitic capacitive coupling associated with one or more metal traces coupled to the set of drive structures;
• the expected signal is derived from a function adapted to fit a plurality of sensed signals from the set of sensed signals;
• and
• the function comprises a third-order fit polynomial function.