Input device, processing system and method for operating electrodes to reduce electromagnetic emissions

Abstract

A method for operating multiple electrodes, as well as a related processing system and input device, is disclosed. The method includes driving a plurality of sensor electrodes with a first signal during a first time period. A first portion of the plurality of sensor electrodes defines a first sensing region within a first zone, and a second portion of the plurality of sensor electrodes defines a first boundary region within the first zone. The method also includes driving a plurality of mitigation electrodes with a second, opposite polarity signal to mitigate electromagnetic emissions generated by driving the plurality of sensor electrodes. The plurality of mitigation electrodes define a second region adjacent to the first boundary region. The method also includes acquiring a first capacitive measurement using the first portion in response to driving the plurality of sensor electrodes.

Description

Technical Field

[0001] Embodiments disclosed herein relate generally to electronic devices and, more particularly, to techniques for actively reducing electromagnetic emissions from input devices using multiple sensor electrodes. Background Art

[0002] Input devices including proximity sensor devices (also commonly referred to as touchpads or touch sensor devices) are widely used in a wide variety of electronic systems. Proximity sensor devices typically include a sensing area, typically distinguished by a surface, in which the proximity sensor device determines the presence, position, and / or motion of one or more input objects. Proximity sensor devices can be used to provide an interface for an electronic system. For example, proximity sensor devices are commonly used as input devices for larger computing systems (such as opaque touchpads integrated into or external to laptop or desktop computers). Proximity sensor devices are also commonly used in smaller computing systems (such as touch screens integrated into cellular phones). Summary of the Invention

[0003] One embodiment described herein is an input device that includes a plurality of sensor electrodes defining a first zone, wherein a first portion of the plurality of sensor electrodes defines a sensing zone within the first zone, and wherein a second portion of the plurality of sensor electrodes defines a boundary zone within the first zone. The input device also includes a plurality of mitigation electrodes defining a second zone adjacent to the boundary zone. The input device also includes a processing system configured to drive the plurality of sensor electrodes with a first signal while driving the plurality of sensor electrodes with a second signal having an opposite polarity to the first signal to mitigate electromagnetic emissions generated by driving the plurality of sensor electrodes. The processing system is further configured to acquire capacitive measurements using the first portion of the plurality of sensor electrodes in response to driving the plurality of sensor electrodes with the first signal.

[0004] Another embodiment described herein is a processing system that includes sensor circuitry for operating a plurality of electrodes, the sensor circuitry configured to drive a plurality of sensor electrodes from the plurality of electrodes with a first signal for a first time period, the plurality of sensor electrodes defining a first region, wherein a first portion of the plurality of sensor electrodes defines a sensing region within the first region, and wherein a second portion of the plurality of sensor electrodes defines a boundary region within the first region. The sensor circuitry is further configured to, while driving the plurality of sensor electrodes for the first time period, drive a plurality of mitigation electrodes from the plurality of electrodes with a second signal having an opposite polarity to the first signal, the plurality of mitigation electrodes defining a second region adjacent to the boundary region to mitigate electromagnetic emissions generated by driving the plurality of sensor electrodes. The sensor circuitry is further configured to acquire a first capacitive measurement using the first portion of the plurality of sensor electrodes during the first time period and in response to driving the plurality of sensor electrodes.

[0005] Another embodiment described herein is a method for operating a plurality of electrodes. The method includes: driving a plurality of sensor electrodes from a plurality of electrodes with a first signal during a first time period, the plurality of sensor electrodes defining a first region, wherein a first portion of the plurality of sensor electrodes defines a sensing region within the first region, and wherein a second portion of the plurality of sensor electrodes defines a boundary region within the first region. The method also includes driving a plurality of mitigation electrodes from the plurality of electrodes with a second signal having an opposite polarity to the first signal while driving the plurality of sensor electrodes during the first time period, the plurality of mitigation electrodes defining a second region adjacent to the boundary region to mitigate electromagnetic emissions generated by driving the plurality of sensor electrodes. The method also includes obtaining a first capacitive measurement using the first portion of the plurality of sensor electrodes in response to driving the plurality of sensor electrodes. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] In order that the above-described features of the present disclosure may be understood in detail, a more particular description of the present disclosure, briefly summarized above, may be given by reference to embodiments, some of which are illustrated in the accompanying drawings. It is noted, however, that the drawings illustrate only exemplary embodiments and are therefore not to be considered limiting of the scope of the invention, as the present disclosure may admit to equally effective embodiments.

[0007] Figure 1 is a schematic block diagram of an input device according to embodiments described herein.

[0008] Figure 2 and Figure 3 Illustrated are portions of an exemplary sensor electrode implementation according to embodiments described herein.

[0009] Figure 4 An exemplary processing system for active reduction of electromagnetic emissions according to embodiments described herein is illustrated.

[0010] Figure 5 A method of performing active reduction of electromagnetic emissions according to embodiments described herein is illustrated.

[0011] Figure 6 A method of determining parameters for performing active reduction of electromagnetic emissions according to embodiments described herein is illustrated.

[0012] Figure 7 is a diagram illustrating an exemplary arrangement of sensor electrodes for performing active reduction of electromagnetic emissions according to embodiments described herein.

[0013] Figure 8 is a diagram illustrating an exemplary arrangement of sensor electrodes for performing active reduction of electromagnetic emissions according to embodiments described herein.

[0014] Figure 9 is a diagram illustrating an exemplary scanning sequence when performing active reduction of electromagnetic emissions according to embodiments described herein.

[0015] Figure 10 is a diagram illustrating an exemplary arrangement with a mitigation zone at least partially surrounding a sensing region according to embodiments described herein.

[0016] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements shared by the accompanying drawings. It is contemplated that elements disclosed in one embodiment may be advantageously used in other embodiments without specific reference. Unless specifically noted, the drawings referred to herein should not be understood as being drawn to scale. Furthermore, for clarity of presentation and explanation, the drawings are often simplified and details or components are omitted. The drawings and discussion serve to illustrate the principles discussed below, where identical reference numerals represent identical elements. DETAILED DESCRIPTION

[0017] The following specific implementations are merely exemplary in nature and are not intended to limit the present disclosure or the application and use of the present disclosure. In addition, there is no intention to be bound by any express or implied theory presented in the foregoing background technology, the invention summary or the following detailed description.

[0018] Various embodiments of the present disclosure provide input devices and methods for improving usability. An input device may include electrodes that operate as sensor electrodes to detect interaction between the input device and an input object (e.g., a stylus or a user's finger). The input device typically drives a sensing signal onto the sensor electrodes to obtain capacitive measurements corresponding to a sensing area. In order to improve the sensing performance of the input device, it may be beneficial to drive the sensing signal onto a large number of sensor electrodes simultaneously (e.g., to measure a larger portion of the sensing area, to protect the measured sensor electrodes from moisture, to reduce the background capacitance presented by the protected sensor electrodes, etc.).

[0019] However, driving the sensing signal over a large portion of the sensing area may generate unacceptably large electromagnetic (EM) emissions. In some cases, specified standards may regulate acceptable levels of EM emissions for specific types of equipment and for specific markets. Some non-limiting examples of regulatory regulations for the automotive market include United Nations Economic Commission for Europe (ECE) Regulation 10, Society of Automotive Engineers (SAE) J1113 series, and CISPR (International Special Committee on Radio Interference) 25.

[0020] According to various embodiments discussed herein, an input device includes a processing system configured to simultaneously drive a first plurality of sensor electrodes with a first signal while driving a plurality of mitigation electrodes with a second signal having an opposite polarity to the first signal. The plurality of mitigation electrodes may include dedicated mitigation electrodes that are not included in capacitive measurements, or may include a second plurality of sensor electrodes. Driving the plurality of mitigation electrodes generally provides a desired mitigation of electromagnetic emissions generated by driving the first plurality of sensor electrodes. In some embodiments, the first plurality of sensor electrodes defines a substantially continuous first region, and the plurality of mitigation electrodes defines a second region adjacent to a boundary region defined within the first region. The processing system uses a first portion of the first plurality of sensor electrodes to obtain capacitive measurements of the sensing region, and uses a second portion of the first plurality of sensor electrodes corresponding to the boundary region to protect the first portion from driving the plurality of mitigation electrodes with the second (opposite polarity) signal. Some potential benefits of the processing system include reduced EM emissions (e.g., within specified standards) without a corresponding reduction in sensing performance (e.g., reduced signal-to-noise ratio).

[0021] Exemplary Input Device Implementations

[0022] Figure 1 1 is a schematic block diagram of an input device 100 according to an embodiment of the present technology. In various embodiments, the input device 100 includes a display device integrated with a sensing device. The input device 100 can be configured to provide input to an electronic system 150. As used in this document, the term "electronic system" (or "electronic device") broadly refers to any system that can electronically process information. Some non-limiting examples of electronic systems include personal computers of all sizes and shapes, such as desktop computers, laptop computers, netbook computers, tablet computers, web browsers, e-book readers, and personal digital assistants (PDAs). Additional example electronic systems include composite input devices, such as a physical keyboard including the input device 100 and a separate joystick or key switch. Other example electronic systems include peripheral devices, such as data input devices (including remote controls and mice) and data output devices (including display screens and printers). Other examples include remote terminals, information stations, and video game consoles (e.g., video game consoles, portable game devices, etc.). Other examples include communication devices (including cellular phones such as smartphones) and media devices (including recorders, editors, and players such as televisions, set-top boxes, music players, digital photo frames, and digital cameras). Additionally, an electronic system can be a host or slave to an input device.

[0023] The input device 100 may be implemented as a physical part of the electronic system, or may be physically separate from the electronic system. As appropriate, the input device 100 may communicate with portions of the electronic system using any one or more of the following: buses, networks, and other wired or wireless interconnects. Example communication protocols include Inter-Integrated Circuit (IC) 2 C), Serial Peripheral Interface (SPI), Personal System / 2 (PS / 2), Universal Serial Bus (USB), Radio Frequency (RF) and Infrared Data Association (IrDA) communication protocols.

[0024] exist Figure 1 , the input device 100 is shown as a proximity sensor device (also commonly referred to as a "touchpad" or "touch sensor device") configured to sense input provided by one or more input objects 140 in a sensing region 170. Example input objects include fingers and styluses, such as Figure 1 As shown in .

[0025] The sensing region 170 encompasses any space above, around, within, and / or near the input device 100 in which the input device 100 is capable of detecting user input (e.g., user input provided by one or more input objects 140). The size, shape, and location of a particular sensing region can vary greatly depending on the embodiment. In some embodiments, the sensing region 170 extends from the surface of the input device 100 in one or more directions into space until the signal-to-noise ratio prevents sufficiently accurate object detection. In various embodiments, the distance to which the sensing region 170 extends in a particular direction can be approximately less than one millimeter, several millimeters, several centimeters, or more, and can vary significantly depending on the type of sensing technology used and the desired accuracy. Thus, in some embodiments, sensed input can include no contact with any surface of the input device 100, contact with an input surface of the input device 100 (e.g., a touch surface), contact with an input surface of the input device 100 coupled with some amount of applied force or pressure, and / or combinations thereof. In various embodiments, the input surface can be provided by a surface of a housing in which the sensor electrodes are located, by a panel applied to the sensor electrodes or any housing, and / or the like. In some embodiments, the sensing region 170 has a rectangular shape when projected onto the input surface of the input device 100 .

[0026] The input device 100 can utilize any combination of sensor components and sensing technologies to detect user input in the sensing region 170. The input device 100 includes a plurality of sensor electrodes 120 for detecting user input. The input device 100 can include one or more sensor electrodes 120 combined to form a sensor electrode. As several non-limiting examples, the input device 100 can use capacitive, inverse dielectric, resistive, inductive, magnetoacoustic, ultrasonic, and / or optical technologies.

[0027] Some implementations are configured to provide images that span one, two, three, or higher dimensional spaces.Some implementations are configured to provide projections of input along a particular axis or plane.

[0028] In some resistive implementations of the input device 100, a flexible and conductive first layer is separated from a conductive second layer by one or more spacer elements. During operation, one or more voltage gradients are created across the layers. Pressing the flexible first layer can cause it to deflect sufficiently to create electrical contact between the layers, resulting in a voltage output reflecting the contact point(s) between the layers. These voltage outputs can be used to determine position information.

[0029] In some inductive implementations of the input device 100, one or more sensor electrodes 120 pick up a loop current induced by a resonant coil or coil pair. Some combination of the amplitude, phase, and frequency of the current can then be used to determine position information.

[0030] In some capacitive implementations of input device 100, a voltage or current is applied to create an electric field. Nearby input objects cause changes in the electric field and produce detectable changes in capacitive coupling that can be detected as changes in voltage, current, etc.

[0031] Some capacitive implementations utilize arrays or other regular or irregular patterns of capacitive sensor electrodes 120 to create an electric field. In some capacitive implementations, separate sensor electrodes 120 can be ohmically shorted together to form a larger sensor electrode. Some capacitive implementations utilize a resistive sheet, which can be uniformly resistive.

[0032] As discussed above, some capacitive implementations utilize a "self-capacitance" (or "absolute capacitance") sensing method based on changes in the capacitive coupling between the sensor electrodes 120 and the input object. In one embodiment, the processing system 110 is configured to drive a voltage having a known amplitude onto the sensor electrodes 120 and measure the amount of charge required to charge the sensor electrodes to the driving voltage. In other embodiments, the processing system 110 is configured to drive a known current and measure the resulting voltage. In various embodiments, an input object near the sensor electrodes 120 changes the electric field near the sensor electrodes 120, thereby changing the measured capacitive coupling. In one implementation, the absolute capacitance sensing method operates by modulating the sensor electrodes 120 relative to a reference voltage (e.g., system ground) using a modulated signal and by detecting the capacitive coupling between the sensor electrodes 120 and the input object 140.

[0033] Additionally, as discussed above, some capacitive implementations utilize a "mutual capacitance" (or "transcapacitive") sensing method based on changes in the capacitive coupling between sensing electrodes. In various embodiments, an input object 140 near the sensing electrodes changes the electric field between the sensing electrodes, thereby changing the measured capacitive coupling. In one implementation, as further described below, a transcapacitive sensing method operates by detecting the capacitive coupling between one or more transmitter sensing electrodes (also referred to as "transmitter electrodes") and one or more receiver sensing electrodes (also referred to as "receiver electrodes"). The transmitter sensing electrodes can be electrically modulated relative to a reference voltage (e.g., system ground) to transmit a transmitter signal. The receiver sensing electrodes can be maintained substantially constant relative to the reference voltage to facilitate reception of the generated signal. The generated signal can include (one or more) effects corresponding to the one or more transmitter signals and / or corresponding to one or more sources of environmental interference (e.g., other electromagnetic signals). The sensing electrodes can be dedicated transmitter electrodes or receiver electrodes, or can be configured to both transmit and receive.

[0034] exist Figure 1 , the processing system 110 is shown as part of the input device 100. The processing system 110 is configured to operate the hardware of the input device 100 to detect input in the sensing area 170. The processing system 110 includes some or all of other circuit components and / or one or more integrated circuits (ICs). For example, a processing system for a mutual capacitance sensor device may include a transmitter circuit configured to transmit signals using transmitter sensor electrodes and / or a receiver circuit configured to receive signals using receiver sensor electrodes. In some embodiments, the processing system 110 also includes electronically readable instructions, such as firmware code, software code, etc. In some embodiments, the components that make up the processing system 110 are located together, such as near the (one or more) sensor electrodes 120 of the input device 100. In other embodiments, the components of the processing system 110 are physically separated, with one or more components being close to the (one or more) sensor electrodes 120 of the input device 100 and one or more components being elsewhere. For example, the input device 100 can be a peripheral device coupled to a desktop computer, and the processing system 110 can include software configured to run on the desktop computer's central processing unit and one or more ICs (possibly with associated firmware) separate from the central processing unit. As another example, the input device 100 can be physically integrated into a mobile device such as a phone, and the processing system 110 can include circuitry and firmware that is part of the phone's main processor. In some embodiments, the processing system 110 is dedicated to implementing the input device 100. In other embodiments, the processing system 110 also performs other functions, such as operating a display screen, driving a haptic actuator, etc.

[0035] The processing system 110 can be implemented as a collection of modules that handle different functions of the processing system 110. Each module can include circuitry, firmware, software, or a combination thereof that is part of the processing system 110. In various embodiments, different combinations of modules can be used. Example modules include hardware operation modules for operating hardware such as sensor electrodes and display screens; data processing modules for processing data such as sensor signals and position information; and reporting modules for reporting information. Additional example modules include a sensor operation module configured to operate the sensor electrodes 120 to detect input, a recognition module configured to recognize gestures (such as mode change gestures), and a mode change module for changing the operating mode. The processing system 110 can also include one or more controllers.

[0036] In some embodiments, processing system 110 directly responds to user input (or lack of user input) in sensing region 170 by causing one or more actions. Example actions include changing operating modes and graphical user interface (GUI) actions such as cursor movement, selection, menu navigation, and other functions. In some embodiments, processing system 110 provides information about the input (or lack of input) to some portion of the electronic system (e.g., to a central processing system of the electronic system that is separate from processing system 110, if such a separate central processing system exists). In some embodiments, some portion of the electronic system processes the information received from processing system 110 to act on the user input, such as to facilitate a full range of actions (including mode change actions and GUI actions).

[0037] For example, in some embodiments, the processing system 110 operates the sensor electrode(s) 120 of the input device 100 to generate an electrical signal indicating an input (or lack of input) in the sensing area 170. The processing system 110 may perform any appropriate amount of processing on the electrical signal when generating information provided to the electronic system. For example, the processing system 110 may digitize the analog electrical signal obtained from the sensor electrode 120. As another example, the processing system 110 may perform filtering or other signal conditioning. As yet another example, the processing system 110 may subtract or otherwise account for a baseline so that the information reflects the difference between the electrical signal and the baseline. As yet other examples, the processing system 110 may determine position information, recognize input as a command, recognize handwriting, and the like.

[0038] As used herein, "position information" broadly encompasses absolute position, relative position, velocity, acceleration, and other types of spatial information. Exemplary "zero-dimensional" position information includes near / far or contact / no-contact information. Exemplary "one-dimensional" position information includes position along an axis. Exemplary "two-dimensional" position information includes motion in a plane. Exemplary "three-dimensional" position information includes instantaneous or average velocity in space. Additional examples include other representations of spatial information. Historical data regarding one or more types of position information may also be determined and / or stored, including, for example, historical data tracking position, motion, or instantaneous velocity over time.

[0039] In some embodiments, input device 100 is implemented with additional input components that are operated by processing system 110 or by some other processing system. These additional input components may provide redundant functionality for input in sensing region 170 or some other functionality. Figure 1 A button 130 is shown near the sensing region 170, which can be used to facilitate selection of items using the input device 100. Other types of additional input components include sliders, balls, wheels, switches, etc. Conversely, in some embodiments, the input device 100 can be implemented without additional input components.

[0040] In some embodiments, the input device 100 includes a touch screen interface, and the sensing area 170 overlaps at least partially with the active area of ​​the display screen of the display device 160. For example, the input device 100 may include a substantially transparent sensor electrode 120 covering the display screen and provide a touch screen interface for the associated electronic system. The display screen can be any type of dynamic display capable of displaying a visual interface to the user, and can include any type of light emitting diode (LED), organic LED (OLED), cathode ray tube (CRT), liquid crystal display (LCD), plasma, electroluminescence (EL) or other display technology. The input device 100 and the display device 160 can share physical elements. For example, some embodiments can utilize some of the same electrical components for display and sensing. As another example, the display device 160 can be operated in part or in whole by the processing system 110.

[0041] It should be understood that while many embodiments of the technology are described in the context of a fully functional device, the mechanisms of the technology can be distributed as a program product (e.g., software) in a variety of forms. For example, the mechanisms of the technology can be implemented and distributed as a software program on an information-bearing medium that is readable by an electronic processor (e.g., a non-transitory computer-readable and / or recordable / writable information-bearing medium readable by processing system 110). Additionally, embodiments of the technology are equally applicable regardless of the specific type of medium used to perform the distribution. Examples of non-transitory, electronically readable media include various disks, memory sticks, memory cards, memory modules, and the like. Electronically readable media can be based on flash memory technology, optical storage technology, magnetic storage technology, holographic storage technology, or any other storage technology.

[0042] Exemplary sensor electrode implementations

[0043] Figure 2 and Figure 3 FIG2 illustrates a portion of an exemplary sensor electrode arrangement according to embodiments described herein. Specifically, according to several embodiments, arrangement 200 ( Figure 2 ) illustrates a portion of a pattern of sensor electrodes configured to sense in a sensing region 170 associated with a pattern. For clarity of illustration and description, Figure 2 The sensor electrodes are shown in a simple rectangular pattern, and various associated components are not shown. The pattern of sensing electrodes includes a first plurality of sensor electrodes 205 (e.g., 205-1, 205-2, 205-3, 205-4) and a second plurality of sensor electrodes 215 (e.g., 215-1, 215-2, 215-3, 215-4). The sensor electrodes 205, 215 are each an example of the sensor electrodes 120 discussed above. In one embodiment, the processing system 110 operates the first plurality of sensor electrodes 205 as a plurality of transmitter electrodes and the second plurality of sensor electrodes 215 as a plurality of receiver electrodes. In another embodiment, the processing system 110 operates the first plurality of sensor electrodes 205 and the second plurality of sensor electrodes 215 as absolute capacitive sensing electrodes.

[0044] The first plurality of sensor electrodes 205 and the second plurality of sensor electrodes 215 are typically ohmically isolated from one another. That is, one or more insulators separate the first plurality of sensor electrodes 205 from the second plurality of sensor electrodes 215 and prevent them from electrically shorting to one another. In some embodiments, the first plurality of sensor electrodes 205 and the second plurality of sensor electrodes 215 can be disposed on a common layer. The plurality of sensor electrodes 205, 215 can be electrically separated by an insulating material disposed at the intersection regions between them; in such a configuration, the first plurality of sensor electrodes 205 and / or the second plurality of sensor electrodes 215 can be formed as jumpers having different portions connecting the same electrode. In some embodiments, the first plurality of sensor electrodes 205 and the second plurality of sensor electrodes 215 are separated by one or more layers of insulating material. In some embodiments, the first plurality of sensor electrodes 205 and the second plurality of sensor electrodes 215 are separated by one or more substrates; for example, they can be disposed on opposite sides of the same substrate, or on different substrates laminated together.

[0045] The plurality of sensor electrodes 205, 215 can be formed into any desired shape. Furthermore, the size and / or shape of the sensor electrodes 205 can be different from the size and / or shape of the sensor electrodes 215. In addition, the sensor electrodes 205, 215 located on the same side of the substrate can have different shapes and / or sizes. In one embodiment, the first plurality of sensor electrodes 205 can be larger (e.g., have a larger surface area) than the second plurality of sensor electrodes 215, although this is not a requirement. In other embodiments, the first plurality of sensor electrodes 205 and the second plurality of sensor electrodes 215 can have similar sizes and / or shapes.

[0046] In one embodiment, the first plurality of sensor electrodes 205 extend substantially in a first direction, and the second plurality of sensor electrodes 215 extend substantially in a second direction. Figure 2 As shown in FIG, first plurality of sensor electrodes 205 extend in one direction, while second plurality of sensor electrodes 215 extend in a direction substantially perpendicular to sensor electrodes 205. Other orientations are possible (eg, parallel or other relative orientations).

[0047] In some embodiments, both the first and second pluralities of sensor electrodes 205, 215 are positioned together to form the exterior of a plurality of (or display stack) layers of the display device 160. One example of a display stack may include layers such as a lens layer, one or more polarizer layers, a color filter layer, one or more display electrode layers, a display material layer, a thin film transistor (TFT) glass layer, and a backlight layer. However, other implementations of a display stack are possible. In other embodiments, one or both of the first and second pluralities of sensor electrodes 205, 215 are located within the display stack, whether included as a separate layer or part of a display-related layer. For example, a Vcom electrode within a particular display electrode layer can be configured to perform both display updating and capacitive sensing.

[0048] Figure 3 Arrangement 300 illustrates a portion of a pattern of sensor electrodes configured to sense in sensing region 170 according to several embodiments. For clarity of illustration and description, Figure 3 The sensor electrodes 120 are shown in a simple rectangular pattern and other associated components are not shown. An exemplary pattern includes sensor electrodes 120 arranged in X columns and Y rows. X，Y , where X and Y are positive integers, although one of X and Y may be zero. It is contemplated that the pattern of sensor electrodes 120 may have other configurations, such as an annular array, a repeating pattern, a non-repeating pattern, a single row or column, or other suitable implementations. Furthermore, in various embodiments, the number of sensor electrodes 120 may vary from row to row and / or column to column. In one embodiment, at least one row and / or column of sensor electrodes 120 is offset from the other rows and / or columns such that it extends further in at least one direction than the other rows. The sensor electrodes 120 are coupled to the processing system 110 and are used to determine the presence (or absence) of an input object in the sensing area 170.

[0049] In the first operating mode, the sensor electrodes 120 (120 1,1 , 120 2,1 , 120 3,1 ,……,120 X,Y ) arrangement can be used to detect the presence of an input object via absolute sensing techniques. That is, the processing system 110 is configured to modulate the sensor electrodes 120 to obtain measurements of changes in capacitive coupling between the modulated sensor electrodes 120 and the input object to determine the position of the input object. The processing system 110 is also configured to determine changes in absolute capacitance based on measurements of the resulting signals received using the modulated sensor electrodes 120.

[0050] In some embodiments, arrangement 300 includes one or more grid electrodes (not shown) disposed between at least two of sensor electrodes 120. The grid electrode(s) can at least partially surround a plurality of sensor electrodes 120 as a group, and can also (or in the alternative) completely or partially surround one or more of sensor electrodes 120. In one embodiment, the grid electrode is a planar body having a plurality of apertures, each of which surrounds a respective one of sensor electrodes 120. In other embodiments, the grid electrode(s) include a plurality of segments or two or more segments that can be driven individually or in groups. The grid electrode(s) can be manufactured similarly to sensor electrodes 120. The grid electrode(s) along with sensor electrodes 120 can be coupled to processing system 110 using conductive routing traces and used for input object detection.

[0051] The sensor electrodes 120 are typically ohmically isolated from each other and are also ohmically isolated from the grid electrode(s). That is, one or more insulators separate the sensor electrodes 120 from the grid electrode(s) and prevent them from electrically shorting to each other. In some embodiments, the sensor electrodes 120 are separated from the grid electrode(s) by an insulating gap, which may be filled with an electrically insulating material, or may be an air gap. In some embodiments, the sensor electrodes 120 and the grid electrode(s) are vertically separated by one or more layers of insulating material. In some other embodiments, the sensor electrodes 120 and the grid electrode(s) are separated by one or more substrates; for example, they may be disposed on opposite sides of the same substrate, or on different substrates. In still other embodiments, the grid electrode(s) may be comprised of multiple layers on the same substrate or on different substrates. In one embodiment, a first grid electrode may be formed on a first substrate (or a first side of a substrate), and a second grid electrode may be formed on a second substrate (or a second side of a substrate). For example, the first grid electrode comprises a substrate disposed on the display device 160 ( Figure 1 ), and the second grid electrode is disposed on the color filter glass of the display device 160. The sizes of the first and second grid electrodes may be the same or different in at least one dimension.

[0052] In the second mode of operation, when the transmitter signal is driven onto the grid electrode(s), the sensor electrodes 120 (120 1,1 , 120 2,1 , 120 3,1 ,……,120 X,Y) can be used to detect the presence of an input object via transcapacitive sensing technology. That is, the processing system 110 is configured to drive the grid electrode(s) with a transmitter signal and is configured to receive the resulting signal with each sensor electrode 120, wherein the resulting signal includes a contribution corresponding to the transmitter signal, which is utilized by the processing system 110 or other processor to determine the position of the input object.

[0053] In a third operating mode, sensor electrodes 120 may be divided into groups of transmitter electrodes and receiver electrodes for detecting the presence of an input object via transcapacitive sensing. That is, processing system 110 may drive a first group of sensor electrodes 120 with a transmitter signal and receive a resulting signal using a second group of sensor electrodes 120, where the resulting signal includes contributions corresponding to the transmitter signal. The resulting signal is then used by processing system 110 or another processor to determine the location of the input object.

[0054] The input device 100 may be configured to operate in any one of the modes described above.The input device 100 may also be configured to switch between any two or more of the modes described above.

[0055] An area of ​​capacitively coupled local capacitive sensing may be referred to as a "capacitive pixel," "touch pixel," "tixel," etc. Capacitive pixels may be formed between a single sensor electrode 120 and a reference voltage in a first operating mode, between a sensor electrode 120 and (one or more) grid electrodes in a second operating mode, and between groups of sensor electrodes 120 serving as transmitter and receiver electrodes (e.g., Figure 2 The capacitive coupling changes with the proximity and movement of an input object in the sensing region 170 associated with the sensor electrode 120 and can therefore be used as an indicator of the presence of an input object in the sensing region of the input device 100.

[0056] In some embodiments, the sensor electrodes 120 are "scanned" to determine these capacitive couplings. That is, in one embodiment, one or more of the sensor electrodes 120 are driven to transmit a transmitter signal. The transmitter can be operated so that one transmitter electrode transmits at a time, or so that multiple transmitter electrodes transmit simultaneously. In the case where multiple transmitter electrodes transmit simultaneously, the multiple transmitter electrodes can transmit the same transmitter signal and thereby create an effectively larger transmitter electrode. Alternatively, the multiple transmitter electrodes can transmit different transmitter signals. For example, the multiple transmitter electrodes can transmit different transmitter signals according to one or more encoding schemes that enable their combined impact on the generated signal of the receiver electrode to be independently determined. In one embodiment, the multiple transmitter electrodes can transmit the same transmitter signal simultaneously, and the receiver electrodes receive the impact and are measured according to the scanning scheme.

[0057] The sensor electrodes 120 configured as receiver sensor electrodes can be operated individually or in multiples to obtain the generated signals. The generated signals can be used to determine the measurement results of the capacitive coupling at the capacitive pixel. The processing system 110 can be configured to receive using the sensor electrodes 120 in a scanning manner and / or multiplexed manner to reduce the number of simultaneous measurements to be performed and the size of the supporting electrical structure. In one embodiment, one or more sensor electrodes are coupled to the receiver of the processing system 110 via a switching element such as a multiplexer. In such an embodiment, the switching element can be inside the processing system 110 or outside the processing system 110. In one or more embodiments, the switching element can also be configured to couple the sensor electrode 120 to a transmitter or other signal and / or voltage potential. In one embodiment, the switching element can be configured to couple more than one receiver electrode to a common receiver at the same time.

[0058] In other embodiments, "scanning" the sensor electrodes 120 to determine these capacitive couplings includes modulating one or more of the sensor electrodes and measuring the absolute capacitance of the one or more sensor electrodes. In another embodiment, the sensor electrodes can be operated such that more than one sensor electrode is driven and configured to receive at a time. In such an embodiment, absolute capacitive measurements can be obtained simultaneously from each of the one or more sensor electrodes 120. In one embodiment, each of the sensor electrodes 120 is driven and configured to receive simultaneously, and absolute capacitive measurements are obtained from each of the sensor electrodes 120 simultaneously. In various embodiments, the processing system 110 can be configured to selectively modulate a portion of the sensor electrodes 120. For example, the sensor electrodes can be selected based on, but not limited to, an application running on the host processor, the state of the input device, and the operating mode of the sensing device. In various embodiments, the processing system 110 can be configured to selectively shield at least a portion of the sensor electrodes 120 and to selectively shield or transmit with the grid electrode(s) 122 while selectively receiving and / or transmitting with other sensor electrodes 120.

[0059] The collection of measurements from the capacitive pixels forms a "capacitive image" (also called a "capacitive frame") that represents the capacitive coupling at the pixel. Multiple capacitive images can be acquired over multiple time periods, and the differences between them are used to derive information about the input in the sensing region. For example, consecutive capacitive images acquired over consecutive time periods can be used to track the motion of one or more input objects entering, leaving, and within the sensing region.

[0060] In any of the above embodiments, a plurality of sensor electrodes 120 may be coupled together such that the sensor electrodes 120 are modulated simultaneously or used to receive simultaneously. Compared to the methods described above, coupling a plurality of sensor electrodes together may produce a coarse capacitive image that may not be useful for discerning precise position information. However, the coarse capacitive image may be used to sense the presence of an input object. In one embodiment, the coarse capacitive image may be used to move the processing system 110 or the input device 100 out of a "doze" mode or a low-power mode. In one embodiment, the coarse capacitive image may be used to move a capacitive sensing IC out of a "doze" mode or a low-power mode. In another embodiment, the coarse capacitive image may be used to move at least one of a host IC and a display driver out of a "doze" mode or a low-power mode. The coarse capacitive image may correspond to the entire sensor area or only a portion of the sensor area.

[0061] The background capacitance of the input device 100 is the capacitive image associated with the absence of an input object in the sensing area 170. The background capacitance varies with environmental and operating conditions and can be estimated in various ways. For example, when no input object is determined to be in the sensing area 170, some embodiments employ "baseline images" and use those baseline images as estimates of their background capacitance. Background capacitance or baseline capacitance can exist due to stray capacitive coupling between two sensor electrodes or due to stray capacitive coupling between a receiver electrode and a nearby modulation electrode (where one sensor electrode is driven with a modulated signal and the other remains fixed relative to system ground). In many embodiments, the background or baseline capacitance can be relatively fixed over the time period when the user is inputting a gesture.

[0062] The capacitive image can be adjusted for the background capacitance of the input device 100 for more efficient processing. Some embodiments achieve this by “baselining” the measurements of the capacitive coupling at the capacitive pixels to produce a “baselined capacitive image.” That is, some embodiments compare the measurements forming the capacitive image with appropriate “baseline values” of a “baseline image” associated with those pixels and determine changes based on the baseline image.

[0063] In some touch screen embodiments, one or more of the sensor electrodes 120 include one or more display electrodes for updating the display screen's display. The display electrodes may include one or more elements of an active matrix display, such as one or more segments of a segmented Vcom electrode (common electrode(s), source drive lines, gate lines, anode subpixel electrodes, or cathode pixel electrodes, or any other suitable display element. These display electrodes may be disposed on an appropriate display screen substrate. For example, the common electrode may be disposed on a transparent substrate (glass substrate, TFT glass, or any other transparent material) in some display screens (e.g., in-plane switching (IPS), fringe field switching (FFS), or plane-line switching (PLS) organic light emitting diodes (OLEDs)), on the bottom of the color filter glass (e.g., patterned vertical alignment (PVA) or multi-domain vertical alignment (MVA)) in some display screens, above the emissive layer (OLED), and the like. In such embodiments, the display electrode may also be referred to as a "combination electrode" because it performs multiple functions. In various embodiments, each of the sensor electrodes 120 includes one or more common electrodes. In other embodiments, at least two sensor electrodes 120 may share at least one common electrode. Although the following description may describe the sensor electrodes 120 and / or (one or more) grid electrodes as comprising one or more common electrodes, various other display electrodes as described above may also be used in conjunction with or as an alternative to the common electrodes. In various embodiments, the sensor electrodes 120 and (one or more) grid electrodes comprise the entire common electrode layer (Vcom electrode).

[0064] In various touch screen embodiments, the "capacitive frame rate" (the rate at which continuous capacitive images are acquired) can be the same as or different from the "display frame rate" (the rate at which the displayed image is updated, including refreshing the screen to re-display the same image). In various embodiments, the capacitive frame rate is an integer multiple of the display frame rate. In other embodiments, the capacitive frame rate is a fractional multiple of the display frame rate. In yet other embodiments, the capacitive frame rate can be any fractional or integer multiple of the display frame rate. In one or more embodiments, the display frame rate can change (e.g., to reduce power or provide additional image data such as 3D display information) while the touch frame rate remains constant. In other embodiments, the display frame rate can remain constant when the touch frame rate is increased or decreased.

[0065] Continue to refer Figure 3The processing system 110 coupled to the sensor electrodes 120 includes a sensor module 310 and an optional display driver module 320. The sensor module 310 includes circuitry configured to drive at least one of the sensor electrodes 120 for capacitive sensing during a period of desired input sensing. In one embodiment, the sensor module 310 is configured to drive a modulated signal onto at least one sensor electrode 120 to detect a change in absolute capacitance between the at least one sensor electrode and an input object. In another embodiment, the sensor module 310 is configured to drive a transmitter signal onto at least one sensor electrode 120 to detect a change in transcapacitance between the at least one sensor electrode and another sensor electrode 120. The modulated and transmitter signals are typically varying voltage signals that include multiple voltage transitions within a time period allocated for input sensing. In various embodiments, the sensor electrodes 120 and / or the grid electrode(s) can be driven differently in different operating modes. In one embodiment, the sensor electrodes 120 and / or the grid electrode(s) can be driven with signals (modulated signal, transmitter signal, and / or shielding signal) that can differ in any of phase, amplitude, and / or shape. In various embodiments, the modulated signal and the transmitter signal are similar in at least one aspect of shape, frequency, amplitude, and / or phase. In other embodiments, the modulated signal and the transmitter signal are different in frequency, shape, phase, amplitude, and phase. The sensor module 310 can be selectively coupled to one or more of the sensor electrodes 120 and / or (one or more) grid electrodes. For example, the sensor module 310 can be coupled to a selected portion of the sensor electrodes 120 and operate in an absolute or transcapacitive sensing mode. In another example, the sensor module 310 can be a different portion of the sensor electrodes 120 and operate in an absolute or transcapacitive sensing mode. In yet another example, the sensor module 310 can be coupled to all sensor electrodes 120 and operate in an absolute or transcapacitive sensing mode.

[0066] Sensor module 310 is configured to operate the grid electrode(s) as shield electrodes, which can shield sensor electrodes 120 from the effects of nearby conductors. In one embodiment, the processing system is configured to operate the grid electrode(s) as shield electrodes, which can "shield" sensor electrodes 120 from the effects of nearby conductors and protect sensor electrodes 120 from the grid electrode(s), thereby at least partially reducing parasitic capacitance between the grid electrode(s) and sensor electrodes 120. In one embodiment, a shield signal is driven onto the grid electrode(s). The shield signal can be a ground signal, such as a system ground or other ground, or any other constant voltage (i.e., unmodulated) signal. In another embodiment, operating the grid electrode(s) as shield electrodes can include electrically floating the grid electrodes. In one embodiment, the grid electrode(s) can operate as effective shield electrodes while being electrically floated due to their large coupling to other sensor electrodes. In other embodiments, the shield signal can be referred to as a "guard signal," where the guard signal is a varying voltage signal having at least one of a phase, frequency, and amplitude similar to the modulating signal driven onto the sensor electrodes. In one or more embodiments, due to the routing beneath the grid electrode(s) and / or sensor electrode 120 , the routing traces may be shielded from responding to input objects and therefore may not be part of the active sensor electrodes, shown as sensor electrode 120 .

[0067] In one or more embodiments, capacitive sensing (or input sensing) and display updating may occur during at least partially overlapping periods. For example, when a common electrode is driven for display updating, the common electrode may also be driven for capacitive sensing. In another embodiment, capacitive sensing and display updating may occur during non-overlapping periods (also referred to as non-display update periods). In various embodiments, the non-display update period may occur between display line update periods for two display lines of a display frame and may be at least as long in time as the display update period. In such embodiments, the non-display update period may be referred to as a "long horizontal blanking period," "long h-blanking period," or "distributed blanking period," where the blanking period occurs between two display update periods and is at least as long as the display update period. In one embodiment, the non-display update period occurs between the display line update periods of a frame and is long enough to allow multiple transitions of the transmitter signal to be driven onto the sensor electrodes 120. In other embodiments, the non-display update period may include a horizontal blanking period and a vertical blanking period. The processing system 110 may be configured to drive the sensor electrodes 120 for capacitive sensing during any one or more or any combination of the different non-display update times. Synchronization signals can be shared between the sensor module 310 and the display driver module 320 to provide accurate control of overlapping display update and capacitive sensing periods with repeatable coherent frequency and phase. In one embodiment, these synchronization signals can be configured to allow relatively stable voltages at the beginning and end of the input sensing period to coincide with display update periods with relatively stable voltages (e.g., near the end of the input integrator reset time and near the end of the display charge sharing time). The modulation frequency of the modulation signal or transmitter signal can be at a harmonic of the display line update rate, with the phase determined to provide nearly constant charge coupling from the display elements to the receiver electrodes, thereby allowing this coupling to be part of the baseline image.

[0068] The sensor module 310 includes circuitry configured to receive generated signals using the sensor electrodes 120 and / or the grid electrode(s) including the effect corresponding to the modulated signal or transmitter signal during a period of desired input sensing. The sensor module 310 may determine the position of an input object in the sensing region 170, or may provide a signal including information indicating the generated signals to another module or processor (e.g., a determination module or processor of an associated electronic device 150 (i.e., a host processor)) for use in determining the position of an input object in the sensing region 170.

[0069] Display driver module 320 may be included in or separate from processing system 110. Display driver module 320 includes circuitry configured to provide display image update information to the display of display device 160 during non-sensing (eg, display updating) periods.

[0070] In one embodiment, the processing system 110 includes a first integrated controller that includes the display driver module 320 and at least a portion of the sensor module 310 (i.e., the transmitter module and / or the receiver module). In another embodiment, the processing system 110 includes a first integrated controller that includes the display driver module 320; and a second integrated controller that includes the sensor module 310. In yet another embodiment, the processing system includes a first integrated controller that includes the display driver module 320 and a first portion of the sensor module 310 (e.g., one of the transmitter module and the receiver module); and a second integrated controller that includes a second portion of the sensor module 310 (e.g., the other of the transmitter module and the receiver module). In those embodiments that include multiple integrated circuits, a synchronization mechanism can be coupled between them and configured to synchronize display update periods, sensing periods, transmitter signals, display update signals, etc.

[0071] Example arrangements for active reduction of electromagnetic emissions

[0072] Figure 4 An exemplary processing system for active reduction of electromagnetic emissions according to embodiments described herein is illustrated. More specifically, arrangement 400 provides one possible implementation of the processing system 110 discussed above. Furthermore, arrangement 400 can be used in conjunction with various embodiments discussed herein, such as those discussed above with respect to Figure 2 and Figure 3 Arrangements 200 , 300 of sensor electrodes are discussed.

[0073] In arrangement 400, sensor module 310 is configured to determine a plurality of sensor electrode sets 405. The plurality of sensor electrode sets 405 can be predetermined, dynamically determined, and / or dynamically updated. In some embodiments, the sensor electrodes of a first set S1 define a sensing region, the sensor electrodes of a second set S2 define a boundary region, and the sensor electrodes of a third set S3 define a mitigation region. The sensor electrodes of the first set S1 can be driven with a sensing signal 430, the sensor electrodes of the second set S2 can be driven with a guard signal 435, and the sensor electrodes of the third set S3 can be driven with a mitigation signal 440. In some alternative embodiments, the sensor electrodes of the third set S3 can be replaced by dedicated mitigation electrodes that are used for EM emission mitigation and are not included in the capacitive measurements acquired by sensor module 310. The dedicated mitigation electrodes can be included in the same layer as the sensor electrodes or in a different layer than the sensor electrodes. For example, the dedicated mitigation electrode can be formed from the same conductive material(s) as the sensor electrodes (e.g., a substantially transparent material such as indium tin oxide (ITO), a transparent conductive oxide (TCO), a carbon nanotube film, a nanowire mesh, etc.), or from a different conductive material(s) (e.g., a non-transparent metal trace). In some cases, the dedicated mitigation electrode can be visually obscured, for example, by being disposed beneath a black mask layer surrounding the visible portion of the display device. In these cases, one or more sensor electrodes of the second set S2 (i.e., the border region) can also be visually obscured. In some alternative embodiments, the sensor electrodes of the second set S2 can also be replaced by dedicated mitigation electrodes that are not included in the capacitive measurements.

[0074] In some embodiments, the sensor module 310 is configured to perform a scan of multiple sensor electrodes (e.g., obtaining capacitive measurements corresponding to a complete sensing frame) by updating a first set S1 of sensor electrodes during one or more sensing periods. In one non-limiting example, the first set S1 corresponds to half of the first sensing axis during the first period and to the other half of the first sensing axis during the second period. Other fractional portions are also possible and may include non-overlapping or overlapping portions. The first set S1 may also correspond to half of the second sensing axis during the third period and to the other half of the second sensing axis during the fourth period. In some embodiments, the second sensing axis is substantially perpendicular to the first sensing axis. In this way, the sensor module 310 can be configured to perform capacitive sensing for the entire sensing axis sequentially for one or more sensing axes.

[0075] The properties of sensing signal 430, guard signal 435, and / or mitigation signal 440 can be selected to perform active reduction of EM emissions caused at least in part by driving sensing signal 430 onto first set S1 of sensor electrodes. Sensing signal 430 can be a time-varying voltage signal (i.e., a modulated signal) having a first polarity. Guard signal 435 typically has a similar phase, frequency, and / or amplitude as sensing signal 430. In some embodiments, guard signal 435 is substantially identical to sensing signal 430. Based on the selected properties, guard signal 435 and sensing signal 430 can have substantially the same first polarity. In some embodiments, mitigation signal 440 has a second polarity that is opposite to the first polarity. For example, mitigation signal 440 can be based on an inverted or phase-shifted copy of sensing signal 430.

[0076] The sensor module 310 is configured to determine one or more of a plurality of signal amplitudes 415 for generating a sensing signal 430, a guard signal 435, and / or a mitigation signal 440. In some embodiments, the guard signal 435 and the sensing signal 430 have the same amplitude M1. The amplitude M2 ​​of the mitigation signal 440 can be selected to provide a desired mitigation of the EM emissions generated by driving the sensing signal 430 and the guard signal 435, the amplitude M2 ​​being selected based, in some cases, at least in part, on the amplitude M1. Although not explicitly discussed, in alternative embodiments, different mitigation signals can be driven (e.g., having different amplitude values) onto different sensor electrodes of the second set S2.

[0077] In some embodiments, amplitude M2 ​​may also be based on at least one of the following: the number of sensor electrodes included in the first set S1, the area defined by the first set S1, the number of sensor electrodes included in the second set S2, the area defined by the second set S2, the number of sensor electrodes included in the third set S3, and the area defined by the third set S3 (or alternatively, the area defined by multiple dedicated mitigation electrodes). In one example, the first zone includes the sensing zone defined by the first set S1 and the boundary zone defined by the second set S2, and the second zone includes the mitigation zone defined by the third set S3. As discussed herein, the first zone includes a "substantially continuous" zone in which substantially all of the sensor electrodes included therein are driven with signals having the same polarity(ies). The substantially continuous zone may include non-sensing areas, such as insulating areas between different sensor electrodes. Although substantially all of the sensor electrodes of a substantially continuous zone are driven with signals having the same polarity(ies), in some cases, the substantially continuous zone may include one or more other sensor electrodes that are driven with different signals (e.g., a DC signal or AC signal having another polarity), are grounded, are electrically floating, etc. In this case, one or more other sensor electrodes should only comprise a relatively small portion of the zone, such as 10% or less of the zone. In some cases, the substantially continuous first zone corresponds to a first area that is larger than a second area that corresponds to the second zone. To appropriately mitigate EM emissions from driving sensor electrodes within the (larger) substantially continuous first zone, amplitude M2 ​​can be selected to be greater than amplitude M1.

[0078] In some embodiments, the sensor module 310 is configured to determine one or more of a plurality of zone values ​​410. In some embodiments, the first zone A1 corresponds to a sensing zone (defined by the first set S1), the second zone A2 corresponds to a boundary zone (defined by the second set S2), and the third zone A3 corresponds to a mitigation zone (defined by the third set S3). The sensor module 310 may determine the first zone (corresponding to a substantially continuous first zone) based on the first zone A1 and the second zone A2, and / or may determine the second zone based on the third zone A3. In some cases, the sensor module 310 is configured to select sensor electrodes for one or more of the first set S1, the second set S2, and the third set S3 based on expected values ​​for the first zone A1, the second zone A2, and / or the third zone A3.

[0079] In some embodiments, sensor module 310 is configured to determine the properties of the generated signal and / or one or more of the plurality of sensor electrode sets 405 based on one or more emission parameters 420. For example, emission parameters 420 may include broadband emission limits and / or narrowband emission limits included in a prescribed standard. Some non-limiting examples of regulatory regulations that provide prescribed standards for the automotive market include UNECE Regulation 10, SAE J1113 series, and CISPR 25. Emission parameters 420 may be defined in power units such as milliwatts (mW) or decibel milliwatts (dBm), in field strength units such as decibel microvolts (dBuV), or any alternative suitable units. Sensor module 310 may also include one or more emission measurements 425. In one embodiment, sensor module 310 is communicatively coupled to an antenna (e.g., disposed at a prescribed distance from the radiation sensor electrodes) and acquires emission measurements 425 using the antenna (not shown). In another embodiment, sensor module 310 is communicatively coupled to a test device and receives emission measurements 425 from the test device (not shown). The sensing module 310 is further configured to adjust the generated signal and / or properties of one or more of the plurality of sensor electrode sets 405 based on the emission measurements 425. For example, if the one or more emission measurements 425 indicate that the emission limit(s) included in the one or more emission parameters 420 are exceeded, the sensing module 310 may be configured to perform at least one of the following: (1) change the composition and / or size of the first set S1 and / or the second set S2; (2) change the composition and / or size of the third set S3; (3) reduce the amplitude M1; and (4) increase the amplitude M2 ​​of the mitigation signal 440.

[0080] Figure 5 A method 500 for performing active reduction of electromagnetic emissions according to embodiments described herein is illustrated. The method 500 may be combined with other embodiments such as Figure 4 More specifically, the method 500 may be performed during operation of the sensor module 310 of the arrangement 400.

[0081] Method 500 begins at block 505, where a sensor module drives a first plurality of sensor electrodes with a first signal for a first period of time. The first plurality of sensor electrodes may define a substantially continuous first region. Within the substantially continuous first region, a first portion of the first plurality of sensor electrodes defines a first sensing region, and a second portion of the first plurality of sensor electrodes defines a first boundary region.

[0082] At block 515, the sensor module drives a plurality of mitigation electrodes with a second signal having an opposite polarity to the first signal while driving the first plurality of sensor electrodes. The plurality of mitigation electrodes define a second region adjacent to the first boundary region. In some embodiments, the plurality of mitigation electrodes are dedicated mitigation electrodes that are not included in the acquired capacitive measurements. In other embodiments, the plurality of mitigation electrodes comprise the second plurality of sensor electrodes.

[0083] At block 525, the sensor module acquires a first capacitive measurement using a first portion of the first plurality of sensor electrodes in response to driving the first plurality of sensor electrodes. The first capacitive measurement corresponds to a first sensing region. The first capacitive measurement may reflect an absolute capacitive measurement and / or a mutual capacitive measurement acquired using the first portion of the first plurality of sensor electrodes. In some embodiments, a second portion of the first plurality of sensor electrodes operates as a guard electrode for the first portion of the first plurality of sensor electrodes, and the first capacitive measurement does not include the second portion of the first plurality of sensor electrodes.

[0084] At block 535, the sensor module drives a third plurality of sensor electrodes with a third signal for a second period of time. The third plurality of sensor electrodes may define a substantially continuous third region that is different from the substantially continuous first region. Within the substantially continuous third region, a third portion of the third plurality of sensor electrodes defines a second sensing region, and a fourth portion of the third plurality of sensor electrodes defines a second boundary region.

[0085] At block 545, the sensor module drives a second plurality of mitigation electrodes with a fourth signal having an opposite polarity to the third signal while driving the third plurality of sensor electrodes. The second plurality of mitigation electrodes defines a fourth region adjacent to the second boundary region. The second plurality of mitigation electrodes may include dedicated mitigation electrodes that are not included in the acquired capacitive measurements, or may include a fourth plurality of sensor electrodes.

[0086] At block 555, in response to driving the third plurality of sensor electrodes, the sensor module acquires a second capacitive measurement using the third portion. In some embodiments, the first capacitive measurement and the second capacitive measurement can be used to perform a complete scan of the plurality of sensor electrodes along one or more sensing axes. Method 500 ends after block 555 is completed.

[0087] Figure 6 A method 600 for determining parameters for performing active reduction of EM emissions according to embodiments described herein is illustrated. The method 600 may be combined with other embodiments such as Figure 4 The processing system of arrangement 400 and / or Figure 5More specifically, the method 600 may be performed as part of a sensor module that initially determines and / or updates a capacitive sensing configuration.

[0088] Method 600 begins at block 605, where the sensor module determines a first amplitude of a first signal to be driven onto a plurality of sensor electrodes defining a substantially continuous first region. In some embodiments, the first amplitude is a predetermined value.

[0089] At block 615, the sensor module determines a first set of sensor electrodes corresponding to a first portion of the first plurality of sensor electrodes. The first portion of the plurality of sensor electrodes defines a sensing zone within the substantially continuous first zone. At block 625, the sensor module determines a second set of sensor electrodes corresponding to a second portion of the first plurality of sensor electrodes. The second portion of the plurality of sensor electrodes defines a protection zone within the substantially continuous first zone. At block 635, the sensor module determines a third set of sensor electrodes corresponding to a plurality of mitigation electrodes to be driven with a second signal having an opposite polarity to the first signal. The plurality of mitigation electrodes define a mitigation zone adjacent to the protection zone. In some alternative embodiments, the plurality of mitigation electrodes includes a dedicated mitigation electrode that is not included in the acquired capacitive measurements.

[0090] At block 645, the sensor module determines a second amplitude of the second signal based on the first amplitude of the first signal. The second amplitude is also based on at least one of: the number of sensor electrodes included in the first set, the area defined by the first set, the number of sensor electrodes included in the second set, the area defined by the second set, the number of sensor electrodes included in the third set, and the area defined by the third set. In some alternative embodiments with dedicated mitigation electrodes, the second amplitude may be based on the area defined by the dedicated mitigation electrode. Method 600 ends after block 645 is completed. Although blocks 605-645 have been depicted in a particular sequence, the individual blocks may be performed in any other suitable order. In addition, blocks 605-645 may be performed during non-overlapping time periods, or two or more individual blocks may be performed during overlapping time periods.

[0091] Figure 7 is a diagram illustrating an exemplary arrangement 700 of sensor electrodes for performing active reduction of electromagnetic emissions according to embodiments described herein. The sensor electrodes depicted in arrangement 700 may be operated in conjunction with other embodiments, such as using Figure 4 The processing system of arrangement 400 and / or Figure 5 Method 500.

[0092] As shown, the plurality of sensor electrodes depicted in arrangement 700 are arranged in a repeating grid pattern defining a plurality of ten (10) rows and a plurality of eleven (11) columns, although other sizes are possible. Although the plurality of sensor electrodes have diamond shapes of the same size in arrangement 700, other sensor electrode shapes and / or sizes are possible. Some non-limiting examples of sensor electrode shapes include rectangular shapes and hexagonal shapes. Furthermore, the sensor electrodes included in the plurality of rows are different from the sensor electrodes included in the plurality of columns, although this is not a requirement.

[0093] In arrangement 700, each sensor electrode included in a particular row or a particular column is electrically connected so that a desired signal can be driven onto each individual row and onto each individual column during operation. However, other implementations may include individually driven sensor electrodes or different groupings of sensor electrodes.

[0094] As shown, sensor electrodes 120 included in rows 1-5 may be driven with sense signal 430, sensor electrodes 120 in rows 7-10 may be driven with mitigation signal 440, and sensor electrodes 120 included in row 6 may be driven with guard signal 435. In some embodiments, sense signal 430 and guard signal 435 are the same, but sensor electrodes 120 driven with guard signal 435 are not included in the capacitive measurement. Sensor electrodes 120 included in columns 1-11 may be driven with guard signal 435.

[0095] A substantially continuous first region 705 is defined by a first plurality of sensor electrodes 120 driven with either sense signal 430 or guard signal 435. As shown, continuous first region 705 includes sensor electrodes 120 included in rows 1-6 and sensor electrodes 120 of columns 1-11 disposed above row 1 between rows 6 and 7.

[0096] Second region 720 is defined by a second plurality of sensor electrodes 120 driven with mitigation signal 440. As shown, second region 720 includes sensor electrodes 120 included in rows 7-10. Second region 720 also includes sensor electrodes 120 driven with guard signal 435 included in columns 1-11, which are arranged between rows 7 and 8 and below row 10.

[0097] Within first region 705, sensing region 710 is defined by sensor electrodes 120 driven with sensing signal 430. As shown, sensing region 710 extends to include rows 1-5 of sensor electrodes 120. Furthermore, sensor electrodes 120 driven with sensing signal 430 (first portion) and sensor electrodes 120 driven with guard signal 435 (third portion) are arranged in an alternating pattern within sensing region 710.

[0098] Boundary region 715 is defined within continuous first region 705 and is disposed adjacent to second region 720. Sensor electrodes 120 disposed within boundary region 715 may be configured to protect sensing region 120 from mitigation signal 440 driven onto sensor electrodes in second region 120. In some embodiments, the size of boundary region 715 may be determined based on the relative sizes of sensing region 710 and / or second region 720, and / or the relative magnitudes of sensing signal 430 and / or mitigation signal 440.

[0099] Described another way, in some embodiments, during a first time period, a first portion of the first plurality of sensor electrodes (i.e., defining sensing area 710) includes at least the first row of the plurality of rows. A second portion of the plurality of sensor electrodes (i.e., defining boundary area 715) includes at least the second row of the plurality of rows. A second plurality of sensor electrodes (i.e., defining second area 720 adjacent to boundary area 715) includes at least the third row of the plurality of rows. In some embodiments, during the first time period, the sensor electrodes included in the plurality of columns are operated as guard sensor electrodes. During a different second time period, the first portion, the second portion, and the second plurality of sensor electrodes correspond to different (one or more) columns of the plurality of columns. During the second time period, the sensor electrodes included in the plurality of rows are operated as guard sensor electrodes.

[0100] In some embodiments, the magnitude of the mitigation signal 440 (i.e., M2) can be determined based on the magnitude of the sensing signal 430 (i.e., M1) and the relative areas driven at the first and second magnitudes. For example, the magnitude M2 ​​can be determined according to the following relationship:

[0101]

[0102] Where M1 represents the amplitude of the sensing signal 430 and the amplitude of the protection signal 435, A M1 represents the area of ​​the arrangement 700 driven at amplitude M1, and A M2 represents a region of the arrangement 700 driven at amplitude M2. Figure 7, and assuming that rows 1-10 and columns 1-11 each correspond to a respective 50% of the sensor area, approximately 25% of the total sensor area is driven with sense signal 430 (i.e., rows 1-5), and approximately 55% of the total sensor area is driven with guard signal 435 (i.e., 50% of columns 1-11 and 5% of row 6), which totals to 80% of area A. M1 The remaining 20% ​​of the total sensor area is driven with the mitigation signal 440, corresponding to 20% of area A. M2 Thus, according to equation (1), M2 can be selected as (80% / 20%) times M1, or (4*M1). Thus, driving the sensor electrodes 120 of arrangement 700 with amplitudes M1, M2 results in substantially equal and opposite EM emissions at a particular distance from the plurality of sensor electrodes 120.

[0103] Thus, driving the sensor electrodes of arrangement 700 in the depicted manner may be suitable for acquiring a first capacitive measurement corresponding to half of the first (vertical) sensing axis, including rows 1-5, during a first time period. During a second time period, a second capacitive measurement corresponding to the other half of the first sensing axis may be acquired. In this case, sensor electrodes 120 in rows 6-10 may be driven with sense signal 430, row 5 may be driven with guard signal 435, and rows 1-4 may be driven with mitigation signal 440. Driving the sensor electrodes in columns 1-11 with guard signal 435 may continue. During other time periods, capacitive measurements may be acquired for the second (horizontal) sensing axis, for example, by driving a first portion of sensor electrodes 120 included in columns 1-11 with sense signal 430, a second portion with guard signal 435, and a third portion with mitigation signal 440. Sensor electrodes 120 included in rows 1-10 may be driven with guard signal 435.

[0104] One or more other factors may be considered in determining amplitude M2. The one or more other factors may be applied uniformly across the sensor area (or "symmetrically") and / or differently to different portions of the sensor area (or "asymmetrically"). In some embodiments, and based on the one or more other factors, mitigation is performed during a first time period by driving a first number of sensor electrodes with a mitigation signal 440 having a first amplitude, and mitigation is performed during a second time period using a different, second number of sensor electrodes and / or a different, second amplitude mitigation signal 440. A non-limiting example of the one or more other factors that may affect amplitude M2 ​​is EM emissions from wiring electrodes coupled to sensor electrodes 120. The factors may be applied asymmetrically based on the placement of the wiring electrodes relative to the sensor area. Other non-limiting examples of the one or more other factors include the RC time constants of the sensor electrodes driven with different signals, the polarization of the different signals, and the like.

[0105] Figure 8 is a diagram illustrating an exemplary arrangement 800 of sensor electrodes for performing active reduction of electromagnetic emissions according to embodiments described herein. The sensor electrodes depicted in arrangement 800 may be operated in conjunction with other embodiments, such as using Figure 4 The processing system of arrangement 400 and / or Figure 5 Method 500.

[0106] As shown, the plurality of sensor electrodes depicted in arrangement 800 are arranged in a repeating grid pattern defining a plurality of six (6) rows and a plurality of eight (8) columns, although other sizes are possible. Each of the sensor electrodes in arrangement 800 is included in a particular row and a particular column. In addition, each of the sensor electrodes depicted in arrangement 800 is at least partially surrounded by a grid electrode (such as grid electrodes 805-1A, 805-1B). As shown, each grid electrode surrounds four sensor electrodes, although other numbers of sensor electrodes are possible. In addition, the grid electrodes are arranged in a repeating grid pattern. As shown, grid electrodes 805-1A, 805-1B are arranged in row 1, grid electrode 805-1A is arranged in grid column A, and grid electrode 805-1B is arranged in grid column B.

[0107] In some embodiments, each sensor electrode of arrangement 800 included in a particular row is electrically connected so that a desired signal can be driven onto each individual row during operation. However, other implementations can include individually driven sensor electrodes or sensor electrodes in different groups. For example, each group of four (4) sensor electrodes surrounded by a particular grid electrode can be electrically connected and driven together.

[0108] As shown, the sensor electrodes 120 included in rows 1-3 are driven with a sense signal 430, the sensor electrodes 120 in rows 5 and 6 are driven with a mitigation signal 440, and the sensor electrodes 120 included in row 4 are driven with a guard signal 435. In some embodiments, the sense signal 430 and the guard signal 435 are the same, but the sensor electrodes 120 driven with the guard signal 435 are not included in the capacitive measurement results. Each of the grid electrodes can be driven with the guard signal 435, although in other embodiments, one or more of the grid electrodes can be driven with different signals. For example, the grid electrodes included in rows 5 and 6 (which surround the sensor electrodes 120 driven with the mitigation signal 440) can also be driven with the mitigation signal 440.

[0109] The continuous first region 705 is defined by the first plurality of sensor electrodes 120 driven with the sense signal 430 or with the guard signal 435. As shown, the continuous first region 705 includes the sensor electrodes 120 and the grid electrodes included in rows 1-4.

[0110] The second region 720 is defined by a second plurality of sensor electrodes 120 driven with the mitigation signal 440. As shown, the second region 720 includes sensor electrodes 120 included in rows 5 and 6. In some embodiments, the second region 720 may also include a grid electrode driven with the mitigation signal 440.

[0111] Sensing region 710 is defined by sensor electrodes 120 driven with sensing signal 430. As shown, sensing region 710 extends to include rows 1-3 of sensor electrodes 120. A border region 715 is defined within the continuous first region 705 and is disposed adjacent to the second region 720. Sensor electrodes 120 disposed within border region 715 are generally configured to protect sensing region 120 from mitigation signal 440 driven onto sensor electrodes in the second region 120. In some embodiments, the size of border region 715 can be determined based on the relative sizes of sensing region 710 and / or second region 720, and / or the relative amplitudes of sensing signal 430 and / or mitigation signal 440. In some alternative embodiments, if the grid electrodes (such as grid electrodes 805-1A and 805-1B) are sufficiently large, a distinct border region 715 may not be required to adequately protect the sensor electrodes of sensing region 710.

[0112] Thus, driving the sensor electrodes of arrangement 800 in the depicted manner may be suitable for acquiring a first capacitive measurement during a first time period that includes rows 1-3 of sensor electrodes 120 and corresponds to half of the first (vertical) sensing axis. Consistent with the discussion above, additional capacitive measurements may be acquired along the first sensing axis and / or the second (horizontal) sensing axis during other time periods.

[0113] Figure 9 FIG900 is a diagram illustrating an exemplary scanning sequence when performing active reduction of electromagnetic emissions according to embodiments described herein. The scanning sequence may be performed in conjunction with other embodiments, such as using Figure 7 and Figure 8 900. In the scanning sequence shown in diagram 900, sensing occurs along a first (vertical) sensing axis between times 905-1 and 905-3, and along a second (horizontal) sensing axis between times 905-4 and 905-6.

[0114] At time 905-1, sensing region 710 comprises the uppermost portion of the first sensing axis. Sensing region 710 is separated from second region 720 (i.e., to mitigate signal drive) by boundary region 715. At time 905-2, capacitive measurements are taken from the two separated sensing regions 710-1, 710-2, with second region 720 positioned midway along the first sensing axis. In this case, first boundary region 715-1 separates second region 720 from sensing region 710-1, and second boundary region 715-2 separates second region 720 from sensing region 710-2. At time 905-3, sensing region 710 comprises the lowermost portion of the first sensing axis.

[0115] At time 905-4, sensing region 710 comprises the rightmost portion of the second sensing axis. Sensing region 710 is separated from second region 720 by boundary region 715. At time 905-5, capacitive measurements are taken from the two separated sensing regions 710-1, 710-2, with second region 720 positioned midway along the second sensing axis. In this case, first boundary region 715-1 separates second region 720 from sensing region 710-1, and second boundary region 715-2 separates second region 720 from sensing region 710-2. At time 905-6, sensing region 710 comprises the leftmost portion of the second sensing axis.

[0116] Figure 10 is a diagram illustrating an exemplary arrangement 1000, 1050 with a mitigation zone at least partially surrounding a sensing region according to embodiments described herein. The scanning sequence may be performed in conjunction with other embodiments, such as using Figure 7 and Figure 8 The arrangement 700, 800 of sensor electrodes is depicted in FIG.

[0117] In arrangement 1000, sensing region 710 is partially surrounded by mitigation region(s). More specifically, sensing region 710 is disposed between a first mitigation region (shown as second region 720-1) and a second mitigation region (shown as second region 720-2). In this case, a first boundary region 715-1 separates second region 720-1 from sensing region 710, and a second boundary region 715-2 separates second region 720-2 from sensing region 710. In arrangement 1050, sensing region 710 is completely surrounded by mitigation region (i.e., second region 720). In this case, boundary region 715 also surrounds sensing region 710.

[0118] In some embodiments, the sensing regions 710 of arrangements 1000 and 1050 can have relatively static positioning. Arrangements 1000 and 1050 can be beneficial because capacitive measurements can be acquired for the entire sensing region 710 (e.g., along one or more sensing axes) in a single time period, while the mitigation region(s) can mitigate EM emissions generated by driving the sensor electrodes of the sensing region 710. In some cases, such as in arrangements 1000 and 1050, the mitigation region(s) and the border region(s) can extend along the longest dimension of the sensing region 710. In some cases, such as in arrangement 1050, the mitigation region(s) and / or the border region(s) can have a greater thickness along the longest dimension of the sensing region 710 and a thinner thickness along another dimension of the sensing region 710.

[0119] The features described herein may be embodied in suitable alternative forms. In one non-limiting example, a mitigation signal may be driven for a grouping of software-defined 1D slider buttons and / or software-defined 2D buttons. In the case of 2D buttons, given sufficient distance between the 2D buttons, the processing system may perform capacitive measurements corresponding to one set of 2D buttons by driving a sensing waveform, and may simultaneously measure another set of 2D buttons (having approximately the same area) by driving an inverted waveform. In another non-limiting example, for a system defining multiple touch-sensitive areas, an inverted waveform of appropriate amplitude may be used to achieve net cancellation of the sum across the sensing area.

[0120] Therefore, the embodiments and examples set forth herein are presented in order to best explain embodiments according to the present technology and its specific applications, and to thereby enable those skilled in the art to make and use the present disclosure. However, those skilled in the art will recognize that the foregoing description and examples have been presented for purposes of illustration and example only. The set forth description is not intended to be exhaustive or to limit the present disclosure to the precise forms disclosed.

[0121] In view of the foregoing, the scope of the present disclosure is determined by the following claims.

Claims

1. An input device comprising: a first plurality of sensor electrodes defining a first region, wherein a first portion of the first plurality of sensor electrodes defines a sensing region within the first region, and wherein a second portion of the first plurality of sensor electrodes defines a boundary region within the first region; a plurality of mitigation electrodes comprising a second plurality of sensor electrodes and defining a second region adjacent the boundary region within the first region; a third plurality of sensor electrodes defining a third region different from the first region, wherein a third portion of the third plurality of sensor electrodes defines a sensing region within the third region, and wherein a fourth portion of the third plurality of sensor electrodes defines a boundary region within the third region; a fourth plurality of sensor electrodes defining a fourth region adjacent the boundary region within the third region; and A processing system configured to: driving the plurality of mitigation electrodes with a second signal having an opposite polarity to the first signal while driving the first plurality of sensor electrodes with a first signal during a first time period to mitigate electromagnetic emissions generated by driving the first plurality of sensor electrodes; acquiring capacitive measurements using the first portion of the first plurality of sensor electrodes in response to driving the first plurality of sensor electrodes with the first signal during the first time period; driving the fourth plurality of sensor electrodes with a fourth signal having an opposite polarity to the third signal while driving the third plurality of sensor electrodes with a third signal during a different second time period to mitigate electromagnetic emissions generated by driving the third plurality of sensor electrodes; as well as During the second time period, in response to driving the third plurality of sensor electrodes, second capacitive measurements are acquired using the third portion of the third plurality of sensor electrodes. 2 . The input device of claim 1 , wherein the second signal has an amplitude selected to provide a desired mitigation of electromagnetic emissions.

3. The input device according to claim 2, wherein the first zone corresponds to a first area and the second zone corresponds to a second area smaller than the first area, and The amplitude is greater than the amplitude of the first signal.

4. The input device of claim 1 , wherein the sensing region comprises a third portion of the first plurality of sensor electrodes, and wherein the sensor electrode of the third portion is configured to operate as a guard sensor electrode for the sensor electrode of the first portion.

5. The input device of claim 1 , wherein the first plurality of sensor electrodes are arranged in a repeating grid pattern defining a plurality of rows and a plurality of columns, and in, During the first time period: the first portion of the first plurality of sensor electrodes comprising at least a first row of the plurality of rows, The second portion of the first plurality of sensor electrodes includes at least a second row of the plurality of rows, and The second plurality of sensor electrodes includes at least a third row of the plurality of rows.

6. The input device according to claim 5, wherein the sensor electrodes included in the plurality of rows are different from the sensor electrodes included in the plurality of columns, and in, During the first time period: The sensor electrodes included in the plurality of columns are configured to operate as guard sensor electrodes.

7. The input device according to claim 5, wherein During the second time period: the first portion of the first plurality of sensor electrodes comprising at least a first column of the plurality of columns, The second portion of the first plurality of sensor electrodes includes at least a second column of the plurality of columns, and the second plurality of sensor electrodes includes at least a third column of the plurality of columns.

8. An input device according to claim 1, wherein at least one of (i) a first number of sensor electrodes included in the second portion and (ii) a second number of the plurality of mitigation electrodes are selected to provide a desired mitigation of electromagnetic emissions generated by driving the first plurality of sensor electrodes.

9. The input device of claim 1, wherein the capacitive measurements comprise absolute capacitive sensing measurements of the first portion of sensor electrodes.

10. A processing system comprising: A sensor circuit for operating a plurality of electrodes, the sensor circuit being configured to: driving a first plurality of sensor electrodes of the plurality of electrodes with a first signal for a first time period, the first plurality of sensor electrodes defining a first zone, wherein a first portion of the first plurality of sensor electrodes defines a first sensing region within the first zone, and wherein a second portion of the first plurality of sensor electrodes defines a first boundary region within the first zone; driving a plurality of mitigation electrodes of the plurality of electrodes with a second signal having an opposite polarity to the first signal while driving the first plurality of sensor electrodes during the first time period, the plurality of mitigation electrodes defining a second region adjacent to the first boundary region to mitigate electromagnetic emissions generated by driving the first plurality of sensor electrodes; as well as acquiring a first capacitive measurement using the first portion of the first plurality of sensor electrodes during the first time period and in response to driving the first plurality of sensor electrodes, wherein during the first time period, the plurality of mitigation electrodes includes a second plurality of sensor electrodes in the plurality of electrodes, wherein the sensor circuit is further configured to: driving a third plurality of sensor electrodes among the plurality of electrodes with a third signal for a second, different time period, the third plurality of sensor electrodes defining a third region different from the first region, wherein a third portion of the third plurality of sensor electrodes defines a second sensing region within the third region, and wherein a fourth portion of the third plurality of sensor electrodes defines a second boundary region within the third region; driving a fourth plurality of sensor electrodes of the plurality of electrodes with a fourth signal having an opposite polarity to the third signal while driving the third plurality of sensor electrodes during the second time period, the fourth plurality of sensor electrodes defining a fourth region adjacent to the second boundary region to mitigate electromagnetic emissions generated by driving the third plurality of sensor electrodes; as well as During the second time period and in response to driving the third plurality of sensor electrodes, a second capacitive measurement is acquired using the third portion of the third plurality of sensor electrodes. 11 . The processing system of claim 10 , wherein the first sensing region corresponds to a first sensing axis, and wherein the second sensing region corresponds to the first sensing axis or to a second sensing axis substantially perpendicular to the first sensing axis.

12. The processing system of claim 10, wherein the plurality of electrodes are arranged in a repeating grid pattern defining a plurality of rows and a plurality of columns, wherein said first portion of said first plurality of sensor electrodes comprises at least a first row of said plurality of rows, Wherein the second portion of the first plurality of sensor electrodes includes at least a second row of the plurality of rows, and wherein the plurality of mitigation electrodes includes at least a third row of the plurality of rows.

13. The processing system of claim 12, wherein the sensor electrodes included in the plurality of rows are different from the sensor electrodes included in the plurality of columns, and in, During the first time period, the sensor electrodes included in the plurality of columns are configured to operate as guard sensor electrodes.

14. The processing system of claim 10 , wherein the sensor circuit is further configured to select at least one of (i) a first number of sensor electrodes included in the second portion, (ii) a second number of the plurality of mitigation electrodes, and (iii) an amplitude of the second signal to provide a desired mitigation of electromagnetic emissions generated by driving the first plurality of sensor electrodes.

15. A method of operating a plurality of electrodes, the method comprising: driving a first plurality of sensor electrodes of the plurality of electrodes with a first signal for a first time period, the first plurality of sensor electrodes defining a first zone, wherein a first portion of the first plurality of sensor electrodes defines a first sensing region within the first zone, and wherein a second portion of the first plurality of sensor electrodes defines a first boundary region within the first zone; driving a plurality of mitigation electrodes of the plurality of electrodes with a second signal having an opposite polarity to the first signal while driving the first plurality of sensor electrodes during the first time period, the plurality of mitigation electrodes defining a second region adjacent to the first boundary region to mitigate electromagnetic emissions generated by driving the first plurality of sensor electrodes; as well as acquiring a first capacitive measurement using the first portion of the first plurality of sensor electrodes in response to driving the first plurality of sensor electrodes, wherein during the first time period, the plurality of mitigation electrodes includes a second plurality of sensor electrodes of the plurality of electrodes, the method further comprising: driving a third plurality of sensor electrodes among the plurality of electrodes with a third signal for a second, different time period, the third plurality of sensor electrodes defining a third region different from the first region, wherein a third portion of the third plurality of sensor electrodes defines a second sensing region within the third region, and wherein a fourth portion of the third plurality of sensor electrodes defines a second boundary region within the third region; driving a fourth plurality of sensor electrodes of the plurality of electrodes with a fourth signal having an opposite polarity to the third signal while driving the third plurality of sensor electrodes during the second time period, the fourth plurality of sensor electrodes defining a fourth region adjacent to the second boundary region, wherein driving the fourth plurality of sensor electrodes provides a desired mitigation of electromagnetic emissions generated by driving the third plurality of sensor electrodes; as well as In response to driving the third plurality of sensor electrodes, a second capacitive measurement is acquired using the third portion of the third plurality of sensor electrodes. 16 . The method of claim 15 , wherein the first sensing region corresponds to a first sensing axis, and wherein the second sensing region corresponds to the first sensing axis or to a second sensing axis substantially perpendicular to the first sensing axis.

17. The method according to claim 15, further comprising: At least one of (i) a first number of sensor electrodes included in the second portion, (ii) a second number of the plurality of mitigation electrodes, and (iii) an amplitude of the second signal are selected to provide desired mitigation of electromagnetic emissions generated by driving the first plurality of sensor electrodes.

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