Touch sensing architecture for small form factors
A touch sensor panel operable within small form factor devices utilizes a plurality of discrete column electrodes arranged in a plurality of columns, and a plurality of continuous row electrodes arranged in a plurality of rows. Each column is divided into a plurality of regions, with each region formed from a plurality of electrically connected discrete column electrodes within that column. A scan plan includes a series of mutual capacitance scans wherein discrete column electrode(s) in all regions in all columns are sequentially stimulated, and AC signals indicative of mutual capacitance at certain the continuous row electrode(s) is measured. The scan plan includes a series of projection self-capacitance scans, wherein AC signals indicative of self-capacitance at a plurality of continuous row electrodes is measured for all rows, and AC signals indicative of self-capacitance at the discrete column electrodes in each region of all columns is measured.
1 . A touch sensing system for detecting one or more touches on a device surface occurring at least partially at a same time, comprising:
a touch sensor panel including:
a plurality of discrete column electrodes arranged in a plurality of columns; and
one or more regions in each of the plurality of columns, each region in a particular column including one or more of the discrete column electrodes situated in that column, wherein:
all of the one or more discrete column electrodes in a particular region are electrically connected together, and
the one or more discrete column electrodes in the particular region in the particular column are separated by at least one discrete column electrode associated with a different region;
a plurality of continuous row electrodes arranged in a plurality of rows;
wherein a first continuous row electrode of the plurality of continuous row electrodes situated in a first row surrounds a first subset of the plurality of discrete column electrodes situated in the first row; and
a touch controller communicatively coupled with the touch sensor panel and configured to perform touch sensing by driving the one or more discrete column electrodes in the particular region in the particular column with a stimulation signal.
2 . The touch sensing system of claim 1 , wherein the plurality of discrete column electrodes and the plurality of continuous row electrodes are formed on a same layer.
3 . The touch sensing system of claim 1 , wherein the one or more discrete column electrodes in the particular region in the particular column that are electrically connected together are driven with the stimulation signal from a particular driving circuit.
4 . The touch sensing system of claim 1 , the touch controller further configured to implement a scan plan including both mutual capacitance sensing and self-capacitance sensing utilizing the touch sensor panel.
5 . The touch sensing system of claim 4 , the touch controller further configured to perform the mutual capacitance sensing by:
sequentially driving the one or more discrete column electrodes in each of the one or more regions in each of the plurality of columns with the stimulation signal; and
in accordance with driving the one or more discrete column electrodes in the particular region of the particular column with the stimulation signal, measuring an AC signal at each of the one or more continuous row electrodes at which stimulated one or more discrete column electrodes of the particular region are situated, each measured AC signal indicative of a mutual capacitance at a touch pixel defined at an intersection of each of measured continuous row electrodes and one of the stimulated one or more discrete column electrodes.
6 . The touch sensing system of claim 5 , the touch controller further configured to:
in accordance with driving the one or more discrete column electrodes in the particular region of the particular column with the stimulation signal, couple one or more unstimulated discrete column electrodes to a reference voltage.
7 . The touch sensing system of claim 5 , the touch controller further configured to:
in accordance with the measuring of the AC signal at each of the one or more continuous row electrodes at which the stimulated one or more discrete column electrodes of the particular region are situated, couple one or more unmonitored continuous row electrodes to a reference voltage.
8 . The touch sensing system of claim 4 , the touch controller further configured to perform the self-capacitance sensing by:
driving one or more of the plurality of continuous row electrodes with the stimulation signal; and
in accordance with driving each of the one or more continuous row electrodes with the stimulation signal, measuring an AC signal at each of driven one or more continuous row electrodes, the AC signal measured at each driven continuous row electrode indicative of the self-capacitance at the driven continuous row electrode.
9 . The touch sensing system of claim 8 , the touch controller further configured to:
in accordance with the measuring of the AC signal at each of the driven one or more continuous row electrodes, couple one or more undriven continuous row electrodes to a reference voltage.
10 . The touch sensing system of claim 8 , the touch controller further configured to perform the self-capacitance sensing by:
driving the one or more discrete column electrodes in each region of one or more columns with the stimulation signal; and
in accordance with driving the one or more discrete column electrodes in each region of the one or more columns with the stimulation signal, measuring an AC signal at driven one or more discrete column electrodes in each region of the one or more columns, the AC signal measured indicative of the self-capacitance at that region.
11 . The touch sensing system of claim 10 , the touch controller further configured to:
in accordance with the measuring of the AC signal at the driven one or more discrete column electrodes in each region of the one or more columns, coupling one or more undriven discrete column electrodes to a reference voltage.
12 . A method for detecting one or more touches occurring at least partially at a same time on a touch sensor panel having a plurality of discrete column electrodes arranged in a plurality of columns and a plurality of continuous row electrodes arranged in a plurality of rows, the method comprising:
performing mutual capacitance touch sensing by:
sequentially driving one or more discrete column electrodes in each of one or more regions in each of the plurality of columns with a stimulation signal, wherein:
each region in a particular column includes one or more of the discrete column electrodes situated in that column, the one or more discrete column electrodes in a particular region are separated by at least one discrete column electrode associated with a different region, and
all of the one or more discrete column electrodes in the particular region are electrically connected together, and
in accordance with driving the one or more discrete column electrodes in the particular region, that are electrically connected together and separated by the at least one discrete column electrode associated with the different region, with the stimulation signal, measuring an AC signal at each of the one or more continuous row electrodes at which stimulated one or more discrete column electrodes of the particular region are situated, each measured AC signal indicative of a mutual capacitance at a touch pixel defined at an intersection of each of measured continuous row electrodes and one of the stimulated one or more discrete column electrodes; and
performing self-capacitance touch sensing by:
driving one or more of the plurality of continuous row electrodes with the stimulation signal, and
in accordance with driving the one or more continuous row electrodes with the stimulation signal, measuring an AC signal at each of driven one or more continuous row electrodes, the measured AC signal at each driven continuous row electrode indicative of a self-capacitance at the driven continuous row electrode.
13 . The method of claim 12 , further comprising performing the mutual capacitance sensing by:
in accordance with driving the one or more discrete column electrodes in the particular region with the stimulation signal, coupling one or more unstimulated discrete column electrodes to a reference voltage.
14 . The method of claim 12 , further comprising performing the mutual capacitance sensing by:
in accordance with the measuring of the AC signal at each of the one or more continuous row electrodes at which the stimulated one or more discrete column electrodes of the particular region are situated, coupling one or more unmeasured continuous row electrodes to a reference voltage.
15 . The method of claim 12 , further comprising performing the self-capacitance touch sensing by:
in accordance with the measuring of the AC signal at each of the driven one or more continuous row electrodes, coupling one or more undriven continuous row electrodes to a reference voltage.
16 . The method of claim 12 , further comprising performing the self-capacitance touch sensing by:
driving the one or more discrete column electrodes in each region of one or more columns with the stimulation signal; and
in accordance with driving the one or more discrete column electrodes in each region of the one or more columns with the stimulation signal, measuring an AC signal at driven one or more discrete column electrodes in each region of the one or more columns, the measured AC signal indicative of the self-capacitance at that region.
17 . The method of claim 16 , further comprising:
in accordance with the measuring of the AC signal at the driven one or more discrete column electrodes in each region of the one or more columns, coupling one or more undriven discrete column electrodes to a reference voltage.
18 . A non-transitory computer-readable storage medium storing instructions that, when executed by one or more processors at a touch sensing device including a touch sensor panel, causes the one or more processors to perform a method for detecting one or more touches occurring at least partially at a same time on the touch sensor panel having a plurality of discrete column electrodes arranged in a plurality of columns and a plurality of continuous row electrodes arranged in a plurality of rows, the method comprising:
performing mutual capacitance touch sensing by:
sequentially driving one or more discrete column electrodes in each of one or more regions in each of the plurality of columns with a stimulation signal, wherein:
each region in a particular column includes one or more of the discrete column electrodes situated in that column, the one or more discrete column electrodes in a particular region are separated by at least one discrete column electrode associated with a different region, and
all of the one or more discrete column electrodes in the particular region are electrically connected together, and
in accordance with driving the one or more discrete column electrodes in the particular region, that are electrically connected together and separated by the at least one discrete column electrode associated with the different region, with the stimulation signal, measuring an AC signal at each of the one or more continuous row electrodes at which stimulated one or more discrete column electrodes of the particular region are situated, each measured AC signal indicative of a mutual capacitance at a touch pixel defined at an intersection of each of measured continuous row electrodes and one of the stimulated one or more discrete column electrodes; and
performing self-capacitance touch sensing by:
driving one or more of the plurality of continuous row electrodes with a stimulation signal, and
in accordance with driving the one or more continuous row electrodes with the stimulation signal, measuring an AC signal at each of driven one or more continuous row electrodes, the measured AC signal at each driven continuous row electrode indicative of a self-capacitance at the driven continuous row electrode.
19 . The non-transitory computer-readable storage medium of claim 18 , storing instructions which, when executed by the one or more processors, further causes the one or more processors to:
drive the one or more discrete column electrodes in each region of one or more columns with the stimulation signal; and
in accordance with driving the one or more discrete column electrodes in each region of the one or more columns with the stimulation signal, measure an AC signal at driven one or more discrete column electrodes in each region of the one or more columns, the measured AC signal indicative of the self-capacitance at that region.