Architecture for differential drive and sense touch technology
Differential driving and/or sensing can reduce noise in a touch screen. In some examples, the touch screen can include column and row electrodes routed vertically in the active area. In some examples, the touch electrodes and/or routing traces can be implemented using metal mesh in first and second metal layers. To improve optical performance, overlapping portions of metal mesh can be designed to provide an appearance of uniform width/area. In some examples, a dielectric layer can have an increased thickness and/or a reduced dielectric constant, and/or metal mesh in the first metal layer can be flooded with a transparent conductive material. In some examples, routing traces can be disposed beneath touch electrodes and/or metal mesh for touch electrodes can be flooded with a transparent conductive material without flooding metal mesh for routing traces. In some examples, touch electrodes can be interleaved within a touch node to improve differential cancelation.
1 . A touch screen comprising:
a plurality of display data lines along a first axis;
a plurality of differential driving pairs of touch electrodes along the first axis, wherein a respective differential driving pair comprises a first touch electrode formed of a first plurality of segments in a first layer and a second touch electrode formed of a second plurality of segments in the first layer, wherein the first plurality of segments and the second plurality of segments are interleaved along the first axis; and
a plurality of sensing touch electrodes along a second axis, the plurality of sensing touch electrodes comprising a third touch electrode formed of a third plurality of segments in the first layer and a fourth touch electrode formed of a fourth plurality of segments in the first layer;
wherein a first touch node comprises:
multiple of the first plurality of segments interleaved along the first axis with multiple of the second plurality of segments; and
multiple of the third plurality of segments interleaved along the first axis with multiple of the fourth plurality of segments.
2 . The touch screen of claim 1 , wherein:
a portion of each of the multiple of the first plurality of segments for the first touch node are disposed around a portion of each of the multiple of the third plurality of segments for the first touch node; and
a portion of each of the multiple of the second plurality of segments for the first touch node are disposed around a portion of each of the multiple of the fourth plurality of segments for the first touch node.
3 . The touch screen of claim 1 , wherein the first axis and the second axis are orthogonal.
4 . The touch screen of claim 1 , wherein a pitch a first segment of the third plurality of segments and a first segment of the fourth plurality of segments closest to the first segment of the third plurality of segments is less than a quarter of the pitch of the first touch node.
5 . The touch screen of claim 4 , wherein the third plurality of segments are interconnected at a border region at an edge or outside an active area of the touch screen.
6 . The touch screen of claim 1 , wherein the plurality of sensing touch electrodes is coupled to sensing circuitry in a sensed single-end configuration.
7 . The touch screen of claim 1 , wherein the first plurality of segments is interconnected in an active area of the touch screen and the second plurality of segments is interconnected in the active area of the touch screen.
8 . The touch screen of claim 1 , wherein the first touch node includes at least a pair of the first plurality of segments interleaved with a pair of the second plurality of segments, and at least a pair of the third plurality of segments interleaved with a pair of the fourth plurality of segments.
9 . The touch screen of claim 1 , further comprising:
driving circuitry configured to apply complimentary drive signals to the plurality of differential driving pairs of touch electrodes.
10 . An electronic device comprising:
an energy storage device;
communication circuitry; and
a touch screen comprising:
a plurality of display data lines along a first axis;
a plurality of differential driving pairs of touch electrodes along the first axis, wherein a respective differential driving pair comprises a first touch electrode formed of a first plurality of segments in a first layer and a second touch electrode formed of a second plurality of segments in the first layer, wherein the first plurality of segments and the second plurality of segments are interleaved along the first axis; and
a plurality of sensing touch electrodes along a second axis, the plurality of sensing touch electrodes comprising a third touch electrode formed of a third plurality of segments in the first layer and a fourth touch electrode formed of a fourth plurality of segments in the first layer;
wherein a first touch node comprises:
multiple of the first plurality of segments interleaved along the first axis with multiple of the second plurality of segments; and
multiple of the third plurality of segments interleaved along the first axis with multiple of the fourth plurality of segments.
11 . A touch sensor panel comprising:
a plurality of differential driving pairs of touch electrodes along a first axis parallel to a plurality of display data lines, wherein a respective differential driving pair comprises a first touch electrode formed of a first plurality of segments in a first layer and a second touch electrode formed of a second plurality of segments in the first layer, wherein the first plurality of segments and the second plurality of segments are interleaved along the first axis; and
a plurality of sensing touch electrodes along a second axis, the plurality of sensing touch electrodes comprising a third touch electrode formed of a third plurality of segments in the first layer and a fourth touch electrode formed of a fourth plurality of segments in the first layer;
wherein a first touch node comprises:
multiple of the first plurality of segments interleaved along the first axis with multiple of the second plurality of segments; and
multiple of the third plurality of segments interleaved along the first axis with multiple of the fourth plurality of segments.
12 . The touch sensor panel of claim 11 , wherein:
a portion of each of the multiple of the first plurality of segments for the first touch node are disposed around a portion of each of the multiple of the third plurality of segments for the first touch node; and
a portion of each of the multiple of the second plurality of segments for the first touch node are disposed around a portion of each of the multiple of the fourth plurality of segments for the first touch node.
13 . The touch sensor panel of claim 11 , wherein the first axis and the second axis are orthogonal.
14 . The touch sensor panel of claim 11 , wherein a pitch a first segment of the third plurality of segments and a first segment of the fourth plurality of segments closest to the first segment of the third plurality of segments is less than a quarter of the pitch of the first touch node.
15 . The touch sensor panel of claim 14 , wherein the third plurality of segments are interconnected at a border region at an edge or outside an active area of the touch sensor panel.
16 . The touch sensor panel of claim 11 , wherein the plurality of sensing touch electrodes is coupled to sensing circuitry in a sensed single-end configuration.
17 . The touch sensor panel of claim 11 , wherein the first touch node includes at least a pair of the first plurality of segments interleaved with a pair of the second plurality of segments, and at least a pair of the third plurality of segments interleaved with a pair of the fourth plurality of segments.
18 . The touch sensor panel of claim 11 , further comprising:
driving circuitry configured to apply complimentary drive signals to the plurality of differential driving pairs of touch electrodes.
19 . The touch sensor panel of claim 11 integrated with a display including the display data lines as a touch screen.
20 . The touch sensor panel of claim 19 , wherein the first plurality of segments is interconnected in an active area of the touch screen and the second plurality of segments is interconnected in the active area of the touch screen.