Negative pixel compensation

A circuit comprising:

• multiple first lines, at least one of the first lines being configured to drive the circuit with a stimulation signal and at least one other first lines being configured to receive a first capacitance between an object proximate to the circuit and ground wherein the first lines also include switching circuitry capable of switching each of the first lines into a configuration to drive the circuit with a stimulation signal, and switching each of the first lines into a configuration to receive the first capacitance;
• multiple second lines associated with to the first lines to form pixels and configured to sense a second capacitance at the pixels indicative of a touch by the object;
• and
• a processor programmable for compensating the second capacitance with the first capacitance by calculating a compensation factor based on a grounding condition of the object and adjusting the second capacitance using the compensation factor.

A method comprising:

• switching one or more drive lines of a touch sensitive device to be coupled to a stimulation circuit and switching one or more drive lines of the touch sensitive device to be coupled to a compensation circuit, wherein each drive line can be selectively switched between being coupled to a stimulation circuit and being coupled to a compensation circuit;
• transmitting a stimulation signal to at least one drive line that has been coupled to a stimulation circuit of the touch sensitive device having multiple drive and sense lines;
• receiving a capacitance signal from the at least one drive line that has been coupled to a compensation circuit and sensing a grounding condition of an object touching a touch sensitive device with at least one other drive line;
• and
• compensating sense signals detected on one or more of the sense lines based on the sensed grounding condition by calculating a ratio between a signal indicative of the sensed grounding condition and an estimate based on at least one sense signal.

A touch sensitive device comprising:

• a touch sensor panel configured to sense an object proximate thereto;
• scan logic couplable to the touch sensor panel and configured to perform a scan sequence on the panel to measure a touch by the object at the panel and to measure grounding of the object, by receiving a capacitance signal on at least one of the plurality of drive lines transmitted by at least another one of the plurality of drive lines, wherein the plurality of drive lines can be switchably configured to receive a capacitance signal and to transmit a capacitance signal;
• and
• a processor configured to compensate touch measurements by calculating a compensation factor based on the measured touch by the object and the measured grounding of the object.