CN112840303A

CN112840303A - Digital signal processor and related chip and handheld device

Info

Publication number: CN112840303A
Application number: CN201980002091.3A
Authority: CN
Inventors: 徐荣贵; 徐建昌; 林永福; 徐嘉骏
Original assignee: Shenzhen Goodix Technology Co Ltd
Current assignee: Shenzhen Goodix Technology Co Ltd
Priority date: 2019-09-25
Filing date: 2019-09-25
Publication date: 2021-05-25
Also published as: WO2021056235A1

Abstract

The application discloses a digital signal processor (10) and a related chip and a handheld device. The digital signal processor is used for sensing signals (S) based on a plurality of digital signals_D1～S_Dn) Judging whether an object is close to the upper part of the touch screen or not, wherein the digital signal processor comprises: a signal integration circuit (100) for receiving the plurality of digital sensing signals, generating a plurality of to-be-integrated sensing signal combinations corresponding to the plurality of digital sensing signals according to the plurality of digital sensing signals, and performing a signal integration operation on the plurality of to-be-integrated sensing signal combinations to generate a plurality of integrated sensing signals (S)_I1～S_I(n‑K+1)) The plurality of sensing signal combinations to be integrated each comprise at least two digital sensing signals of the plurality of digital sensing signals; and a proximity event determining circuit (102), coupled to the signal integration circuit, for determining the touch event based on the integrated sensing signalsWhether the object is close to the upper part of the touch screen.

Description

Digital signal processor and related chip and handheld device

Technical Field

The present invention relates to digital signal processing technology, and more particularly, to a digital signal processor, a chip and a handheld device.

Background

With the development and progress of science and technology, mobile electronic devices such as mobile phones, digital cameras, tablet computers, notebook computers and the like have become indispensable tools in people's lives. These electronic devices are often equipped with a touch-operated interface. The touch interfaces include touch keys, touch sliders or touch pulleys, and touch panels or touch screens. In the scheme of the touch screen, the touch screen is used for sensing a capacitance defined by the touch screen and an object and generating an analog sensing signal according to the capacitance. The analog front-end circuit is used for performing analog-to-digital conversion on an analog sensing signal to generate a digital sensing signal, so that the digital signal processor performs subsequent processing based on the digital sensing signal.

The operation of the touch screen, analog front end circuitry, and digital signal processor often affects the ability of the electronic device to sense objects. However, in consideration of design cost, it is impossible to increase the design complexity of the touch screen, the analog front end circuit, and the digital signal processor without limitation. Therefore, in order to simultaneously achieve the sensing capability and the design cost, improving the processing manner of the sensing signal has become an important work item.

Disclosure of Invention

An objective of the present invention is to disclose a digital signal processing technology, and more particularly, to a digital signal processor and related chip and handheld device, so as to solve the above problems.

An embodiment of the application discloses a digital signal processor, is coupled to analog front end circuit, analog front end circuit is coupled to the touch-sensitive screen, the touch-sensitive screen includes a plurality of sensing channels, a plurality of sensing channels are respectively exported a plurality of analog sensing signals according to the electric capacity variation volume that detects in real time, analog front end circuit is used for right a plurality of sensing channels are exported a plurality of analog sensing signals carry out analog-to-digital conversion in order to produce a plurality of digital sensing signals and correspond a plurality of sensing channels respectively. The digital signal processor is used for judging whether an object is close to the touch screen or not based on the plurality of digital sensing signals, and the digital signal processor comprises: a signal integration circuit, coupled to the analog front-end circuit, for receiving the digital sensing signals, generating a plurality of to-be-integrated sensing signal combinations corresponding to the digital sensing signals according to the digital sensing signals, and performing a signal integration operation on the to-be-integrated sensing signal combinations to generate a plurality of integrated sensing signals, wherein the to-be-integrated sensing signal combinations each include at least two digital sensing signals of the digital sensing signals; and a proximity event determining circuit, coupled to the signal integrating circuit, for determining whether the object is in proximity above the touch screen based on the plurality of integrated sensing signals.

An embodiment of the present application discloses a chip. The chip comprises the digital signal processor.

An embodiment of the present application discloses an electronic device. The electronic device comprises the digital signal processor.

The digital signal processor disclosed by the application can improve the signal-to-noise ratio of the sensing signal for judging whether an object approaches the touch screen, so that the accuracy of a judgment result can be improved.

Drawings

FIG. 1 is a block diagram illustrating an embodiment of a digital signal processor applied to a touch screen.

Fig. 2 is a block diagram of the digital signal processor of fig. 1.

Fig. 3 is a schematic diagram of an exemplary operation of the touch screen of fig. 1 sensing an object.

Fig. 4 is a schematic diagram of the digital signal processor of fig. 2 operating under the exemplary operation of fig. 3.

Fig. 5 shows a schematic diagram of sensing signals under the exemplary operation of fig. 3.

Fig. 6 shows a schematic diagram of sensing signals under the exemplary operation of fig. 3.

Fig. 7 is a block diagram of another embodiment of a digital signal processor according to the present application.

Fig. 8 is a schematic diagram of the digital signal processor of fig. 7 operating under the exemplary operation of fig. 3.

Fig. 9 is a block diagram of a digital signal processor according to yet another embodiment of the present application.

Fig. 10 is a schematic diagram of an embodiment of an electronic device in which a chip including the digital signal processor shown in fig. 1, 7 or 9 is applied.

Wherein the reference numerals are as follows:

10 digital signal processor

20 analog front-end circuit

30 touch screen

40 object

50 digital signal processor

60 electronic device

62 chip

64 display screen assembly

100 signal integration circuit

102 proximity event judging circuit

500 weight circuit

502 trial integration circuit

504 integration judgment circuit

506 weight evaluation circuit

510 signal integration circuit

S _D1～S _DnDigital sensing signal

S _A1～S _AnAnalog sensing signal

S _I1～S _I(n-K+1)Integrating sensing signals

S _T1～S _T(n-K+1)Trial and error integration results

S _W1～S _WnWeight signal

X1-Xn sensing channel

Y1-Ym sensing channel

EN enable signal

Detailed Description

The following disclosure provides various embodiments or illustrations that can be used to implement various features of the disclosure. The embodiments of components and arrangements described below serve to simplify the present disclosure. It is to be understood that such descriptions are merely illustrative and are not intended to limit the present disclosure. For example, in the description that follows, forming a first feature on or over a second feature may include certain embodiments in which the first and second features are in direct contact with each other; and may also include embodiments in which additional elements are formed between the first and second features described above, such that the first and second features may not be in direct contact. In addition, the present disclosure may repeat reference numerals and/or characters in the various embodiments. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed.

Moreover, spatially relative terms, such as "under," "below," "over," "above," and the like, may be used herein to facilitate describing a relationship between one element or feature relative to another element or feature as illustrated in the figures. These spatially relative terms are intended to encompass a variety of different orientations of the device in use or operation in addition to the orientation depicted in the figures. The device may be otherwise oriented (e.g., rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

Although numerical ranges and parameters setting forth the broad scope of the application are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain standard deviations found in their respective testing measurements. As used herein, "the same" generally means that the actual value is within plus or minus 10%, 5%, 1%, or 0.5% of a particular value or range. Alternatively, the term "the same" means that the actual value falls within the acceptable standard error of the mean, subject to consideration by those of ordinary skill in the art to which this application pertains. It is understood that all ranges, amounts, values and percentages used herein (e.g., to describe amounts of materials, length of time, temperature, operating conditions, quantitative ratios, and the like) are "the same" unless otherwise specifically indicated or indicated. Accordingly, unless indicated to the contrary, the numerical parameters set forth in the specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained. At the very least, these numerical parameters are to be understood as meaning the number of significant digits recited and the number resulting from applying ordinary carry notation. Herein, numerical ranges are expressed from one end to the other or between the two ends; unless otherwise indicated, all numerical ranges set forth herein are inclusive of the endpoints.

The touch screen is used for sensing capacitance defined by the touch screen and an object and generating an analog sensing signal according to the capacitance, wherein the capacitance is positively correlated to the magnitude of the analog sensing signal. The analog front-end circuit is used for performing analog-to-digital conversion on an analog sensing signal to generate a digital sensing signal, wherein the magnitude of the analog sensing signal is positively correlated to the magnitude of the digital sensing signal.

It should be noted that, in this document, the description "the magnitude of the digital sensing signal" does not mean the magnitude of the amplitude of the digital sensing signal, but means the magnitude of the capacitance corresponding to the encoding of the digital sensing signal.

The digital signal processor determines whether an object is close to the touch screen based on the digital sensing signal, for example, so as to provide a determination result. When the judgment result is more accurate, the more the judgment result can reflect the real situation between the object and the touch screen. The accuracy of the determination result is often affected by the magnitude of the analog sensing signal and the digital sensing signal. More specifically, the accuracy of the determination result is positively correlated to the signal-to-noise ratio of the analog sensing signal and the signal-to-noise ratio of the digital sensing signal. Therefore, it is at least good to improve the signal-to-noise ratio of the digital sensing signal to improve the accuracy of the determination result. The signal processing method of the digital signal processor of the present application can improve the signal-to-noise ratio of the digital sensing signal, and thus can improve the accuracy of the determination result, which is described in detail below.

Fig. 1 is a block diagram illustrating an embodiment of a digital signal processor 10 applied to a touch screen 30. Referring to fig. 1, a digital signal processor 10 is coupled to an analog front end circuit 20. The analog front end circuit 20 is coupled to a touch screen 30. The touch screen 30 includes a plurality of sensing channels X1 to Xn and Y1 to Ym, where n and m are positive integers. The sensing channels X1 to Xn and Y1 to Ym are arranged in an array. In some embodiments, n and m are equal. The operation of the sense channels X1-Xn and Y1-Ym is the same, and for brevity, the sense channels X1-Xn are described as examples.

The sensing channels are used for detecting the capacitance (not shown) in real time. In detail, when no object 40 is close to the touch screen 30, the sensing channels detect a capacitance (not shown), wherein the detected capacitance may be a stray capacitance. On the other hand, when an object 40 approaches the touch screen 30, the sensing channels detect a capacitance (not shown) defined by the touch screen 30 and the object 40. At this time, after the capacitor and the stray capacitor are properly processed, the difference between the capacitor and the stray capacitor, that is, the capacitance variation can be obtained. For simplicity, the function of the sensing channel can be described as: the sensing channel detects the capacitance variation in real time. Accordingly, the channel basis is sensedThe detected capacitance variation outputs an analog sensing signal S_A. In detail, the sensing channel X1 outputs the sensing signal S_A1(ii) a The sensing channel X2 outputs a sensing signal S_A2(ii) a And, the sensing channel Xn outputs the sensing signal S_AnAnd so on.

The analog front-end circuit 20, for example, for the sensing channel X1, is used to output the analog sensing signal S for the sensing channel X1_A1Performs analog-to-digital conversion to generate a digital sensing signal S_D1. Accordingly, the digital sensing signal S_D1Corresponding to sense channel X1. Similarly, the analog front-end circuit 20 also outputs the analog sensing signal S for the other sensing channels X2 to Xn_A2To S_AnThe analog-to-digital conversion is performed, and will not be described herein.

The digital signal processor 10 is used for sensing a plurality of digital sensing signals S_D1To S_DnIt is determined whether an object 40 is in proximity above the touch screen 30. In some embodiments, the digital signal processor 10 is configured to base on a plurality of digital sensing signals S_D1To S_DnIt is determined whether a hover event caused by the object 40 occurs over the touch screen 30. The actual operation of the digital signal processor 10 will be described in detail in the embodiment of fig. 2.

Fig. 2 is a block diagram of the digital signal processor 10 of fig. 1. Referring to fig. 2, the digital signal processor 10 includes a signal integration circuit 100 and a proximity event determination circuit 102.

The signal integration circuit 100 is coupled to the analog front-end circuit 20 of fig. 1 for receiving a plurality of digital sensing signals S_D1To S_DnAnd according to a plurality of digital sensing signals S_D1To S_DnGenerating a plurality of combinations of sensing signals [ S ] to be integrated_D1、S _D2、…、S _D(1+K-1)]、[S _D2、S _D3、…、S _D(2+K-1)]、[S _D3、S _D4、…、S _D(3+K-1)]…, and [ S_D(n-K+1)、S _D(n-K+2)、S _Dn]Which isWhere K represents the number of digital sensing signals in a combination of sensing signals to be integrated. Each combination of the sensing signals to be integrated comprises a plurality of digital sensing signals S_D1To S_DnAt least two digital sensing signals. In some embodiments, each combination of sensing signals to be integrated includes the same number of digital sensing signals. In some embodiments, each combination of sensing signals to be integrated is different from each other. In some embodiments, multiple to-be-integrated sensing signals are combined [ S ]_D1、S _D2、…、S _D(1+K-1)]、[S _D2、S _D3、…、S _D(2+K-1)]、[S _D3、S _D4、…、S _D(3+K-1)]…, and [ S_D(n-K+1)、S _D(n-K+2)、S _Dn]Two of which include at least one common digital sensing signal. For example, the combination of sensing signals [ S ] to be integrated_D1、S _D2、…、S _D(1+K-1)]And [ S ]_D2、S _D3、…、S _D(2+K-1)]Comprising a common digital sensing signal S_D2。

Multiple sensing signal combination [ S ] to be integrated_D1、S _D2、…、S _D(1+K-1)]、[S _D2、S _D3、…、S _D(2+K-1)]、[S _D3、S _D4、…、S _D(3+K-1)]…, and [ S_D(n-K+1)、S _D(n-K+2)、S _Dn]Respectively corresponding to a plurality of digital sensing signals S_D1To S_Dn. In particular, with the combination of the sensing signals [ S ] to be integrated_D1、S _D2、…、S _D(1+K-1)]Take the digital sensing signal S as an example_D1The initial signal for the combination of the sensing signals to be integrated is followed by (K-1) signals. The (K-1) signals and the digital sensing signal S_D1Are combined with the same sensing signal to be integrated. For example, the touch screen 30 includes 7 sensing channels X1-X7, i.e., n is 7;and, one sensing signal combination to be integrated includes 2 digital sensing signals, i.e., K ═ 2. In this example, the signal S is sensed digitally_D1Is the initial signal and is pushed back by 1 signal to obtain the digital sensing signal S_D2Wherein the digital sensing signal S_D1And S_D2Corresponding to two adjacent sensing channels X1 and X2 of the multiple sensing channels X1-X7. Digital sensing signal S_D1And S_D2Belonging to the same sensing signal combination to be integrated, i.e. corresponding to the digital sensing signal S_D1The sensing signals to be integrated are combined as [ S ]_D1、S _D2]。

In addition, the signal integration circuit 100 combines [ S ] a plurality of sensing signals to be integrated_D1、S _D2、…、S _D(1+K-1)]、[S _D2、S _D3、…、S _D(2+K-1)]、[S _D3、S _D4、…、S _D(3+K-1)]…, and [ S_D(n-K+1)、S _D(n-K+2)、S _Dn]Respectively performing signal integration operation to generate multiple integrated sensing signals S_I1To S_I(n-K+1). Combining [ S ] with the sensing signal to be integrated_D1、S _D2、…、S _D(1+K-1)]For example, the signal integration circuit 100 combines [ S ] the sensing signals to be integrated_D1、S _D2、…、S _D(1+K-1)]Performing a signal integration operation to generate an integrated sensing signal S_I1And so on.

In some embodiments, the signal integration circuit 100 generates a plurality of integrated sensing signals S by adding at least two digital sensing signals of each combination of sensing signals to be integrated_I1To S_I(n-K+1). Combining [ S ] with the sensing signal to be integrated_D1、S _D2、…、S _D(1+K-1)]For example, the signal integration circuit 100 combines the sensing signals to be integrated by [ S ]_D1、S _D2、…、S _D(1+K-1)]Digital sensing signal S _D1、S _D2、…、S _D(1+K-1)Adding them to generate an integrated sensing signal S_I1And so on.

The proximity event determining circuit 102 is coupled to the signal integration circuit 100 for integrating the sensing signals S according to a plurality of integration sensing signals S_I1To S_I(n-K+1)It is determined whether an object 40 is in proximity above the touch screen 30. In some embodiments, the proximity event determining circuit 102 is based on a plurality of integrated sensing signals S_I1To S_I(n-K+1)It is determined whether a hover event occurs over the touch screen 30.

Since the proximity event determining circuit 102 determines whether the object 40 is in proximity to the touch screen 30 based on the integrated sensing signal rather than the digital sensing signal, the accuracy of the determination result of the proximity event determining circuit 102 is higher than the accuracy of the determination result obtained by the proximity event determining circuit 102 based on the digital sensing signal. This is because the signal-to-noise ratio of the integrated sensing signal is better than the signal-to-noise ratio of the digital sensing signal.

In detail, the signal-to-noise ratio of the integrated sensing signal can be expressed as the following equation (1), wherein in the following equation (1), the integrated sensing signal S is used_I1For example, and one combination of sense signals to be integrated includes 2 digital sense signals.

Wherein the SNR_I1Representing the integrated sensing signal S_I1The signal-to-noise ratio of (c); and, N_I1Representing the integrated sensing signal S_I1The noise of (2).

Integrating the sensing signal S_I1Is a digital sensing signal S_D1And S_D2The sum of (a) and (b). Also, the digital sensing signal S_D1And S_D2Representing the capacitance variation detected by the sensing channels X1 and X2, respectively. Accordingly, the digital sensing signal S_D1And S_D2The sum of the values can be represented by the total capacitance variation detected by the sensing channels X1 and X2. Thus, the sensing signal S is integrated_I1Can be expressed as equation (2) below.

S _I1＝dC1+dC2 (2)

Wherein dC1 represents the capacitance variation detected by the sensing channel X1; and dC2 represents the capacitance change detected by the sensor channel X2.

Integrating the sensing signal S_I1Noise N of_I1Noise associated with the capacitance variations dC1 and dC2 detected by the sense channels X1 and X2. The noise of the capacitance change dC1 and dC2 is further related to the standard deviation of the capacitance change dC1 and the standard deviation of the capacitance change dC2, respectively, which can be expressed as the following equation (3).

Wherein σ C1 represents the standard deviation of the capacitance change dC 1; and σ C2 represents the standard deviation of the capacitance change dC 2.

By substituting equations (2) and (3) into equation (1), the following equation (4) can be obtained.

The standard deviations σ C1 and σ C2 are substantially the same. Equation (4) can be further simplified to equation (5) below.

Since the sense channel X1 is adjacent to the sense channel X2, the difference between the capacitance change amounts dC1 and dC2 is substantially not large, and can be expressed as the following equation (6).

dC2＝p×dC1 (6)

Where p represents the ratio between the capacitance changes dC1 and dC2, and p is close to 1.

By substituting equation (6) into equation (5), equation (7) below can be obtained.

On the other hand, the snr of the digital sensing signal can be expressed as the following equation (8), wherein in the following equation (8), the digital sensing signal S is used as the signal-to-noise ratio_D1For example.

Wherein the SNR_D1Representing the digital sensing signal S_D1The signal-to-noise ratio of (c); and, N_D1Representing the digital sensing signal S_D1The noise of (2).

Digital sensing signal S_D1Representing the capacitance variation detected by the sensing channel X1. Accordingly, the digital sensing signal S_D1Can be represented by the capacitance change dC1 detected by the sensing channel X1. Thus, the digital sensing signal S_D1Can be expressed as the following equation (9).

S _D1＝dC1 (9)

The noise of the capacitance variation dC1 detected by the sensing channel X1 is related to the standard deviation of the capacitance variation dC1, which can be expressed as the following equation (10).

N _D1＝σC1 (10)

By appropriately substituting equations (9) and (10) into equation (8), equation (11) below can be obtained.

Comparing equations (7) and (11), it is clear that the integrated sensing signal S is_I1SNR of_I1Is substantially greater than the digital sensing signal S_D1SNR of_D1Is/are as follows

P is substantially equal to 1, so that, in brief, the sensing signal S is integrated_I1SNR of_I1Substantially comparing the digital sensing signal S_D1SNR of_D1Big (a)

And (4) doubling.

Therefore, the accuracy of the determination result obtained by the proximity event determination circuit 102 based on the integrated sensing signal is higher than that obtained based on the digital sensing signal.

Fig. 3 is a schematic diagram of an exemplary operation of the touch screen 30 of fig. 1 sensing an object 40. Referring to fig. 3, in this embodiment, the touch screen 30 includes 7 sensing channels X1-X7 and 7 sensing channels Y1-Y7. For simplicity, in the following description, the sensing channels X1 to X7 are taken as examples.

The projected point of the object 40 on the touch screen 30 is located at the intersection of the sensing channels X4 and Y4. Therefore, in the sense channels X1-X7, ideally, the capacitance variation detected by the sense channel X4 is the largest, and the capacitance variations detected by the sense channels X3 and X5 are the second largest. In short, the farther away the sensing channel X4 is, the smaller the capacitance variation detected by the sensing channel is.

Fig. 4 is a diagram illustrating the digital signal processor 10 of fig. 2 operating under the exemplary operation of fig. 3, wherein K is 2 in this embodiment. Referring to fig. 4, the signal integration circuit 100 receives a plurality of digital sensing signals S_D1To S_D7. Signal integration circuit 100Data digital sensing signal S_D1Generating a combination of sensing signals [ S ] to be integrated_D1、S _D2](ii) a According to the digital sensing signal S_D2Generating a combination of sensing signals [ S ] to be integrated_D2、S _D3](ii) a And according to the digital sensing signal S_D3Generating a combination of sensing signals [ S ] to be integrated_D3、S _D4]And so on.

The signal integration circuit 100 combines the sensing signals to be integrated into a [ S ]_D1、S _D2]Performing a signal integration operation to convert the digital sensing signal S into a digital sensing signal S_D1And S_D2Adding to generate an integrated sensing signal S_I1(ii) a To-be-integrated sensing signal combination [ S ]_D2、S _D3]Performing a signal integration operation to convert the digital sensing signal S into a digital sensing signal S_D2And S_D3Adding to generate an integrated sensing signal S_I2(ii) a And, combining [ S ] the sensing signals to be integrated_D3、S _D4]Performing a signal integration operation to convert the digital sensing signal S into a digital sensing signal S_D3And S_D4Adding to generate an integrated sensing signal S_I3And so on.

The proximity event determining circuit 102 is based on a plurality of integrated sensing signals S_I1To S_I6It is determined whether an object 40 is in proximity above the touch screen 30. The proximity event determination circuit 102 obtains a determination result based on the integrated sensing signal with higher accuracy than that based on the digital sensing signal.

Fig. 5 and 6 show schematic diagrams of sensing signals under the exemplary operation of fig. 3. Referring to fig. 5, the horizontal axis represents a sensing channel; and the vertical axis represents the capacitance variation. In fig. 5, only the sensing channels X2, X3, X4, X5, and X6 and the corresponding capacitance variation are illustrated for simplicity. As can be observed from fig. 5, a plurality of digital sensing signals S_D1To S_DnThe corresponding sensing channels X1 to Xn have a gaussian distribution in capacitance variation as a whole. In some comparative embodiments, the digital signal processor 10 is based on a plurality of numbersSensing signal S_D1To S_DnIt is determined whether there is an object 40 above the touch screen 30, and as described in the embodiment of fig. 2, the accuracy of the determination result obtained by the comparative embodiment is low.

Referring to FIG. 6, the horizontal axis represents the equivalent sensing channel; and the vertical axis represents the capacitance variation. It should be noted that the equivalent sensing channel represents the sensing channel equivalent to the integrated sensing signal. The equivalent sensing channel is not a physical channel on the touch screen 30, that is, the equivalent sensing channel is not one of the sensing channels X1-X7.

The present embodiment includes 6 equivalent sensing channels X1 'to X6' corresponding to a plurality of integrated sensing signals S_I1To S_I6. In detail, the equivalent sensing channel X2' represents the integrated sensing signal S_I2The equivalent corresponding sensing channel; and, the equivalent sensing channel X3' represents the integrated sensing signal S_I3The corresponding sensing channel is equivalent, and so on. In FIG. 5, only the equivalent sensing channels X2 ', X3', X4 'and X5' and the corresponding capacitance variation are illustrated for simplicity. As can be observed from FIG. 5, a plurality of integrated sensing signals S_I1To S_I6The corresponding equivalent sensing channels X1 'to X6' have a non-Gaussian distribution in capacitance variation.

In general, if the distribution of the signals for determining whether the object 40 is close to the touch screen 30 is known, it can be determined whether to use the operation mode of the comparative embodiment or the operation mode of the embodiment of fig. 2.

Fig. 7 is a block diagram of another embodiment of a digital signal processor 50 according to the present application. Referring to fig. 7, the dsp 50 is similar to the dsp 10 of fig. 2, except that the dsp 50 further includes a weighting circuit 500, and the signal integration circuit 510 is further modified from the signal integration circuit 100 in response to the weighting circuit 500.

The weighting circuit 500 is coupled to the analog front-end circuit 20 and the signal integration circuit 510 of FIG. 1 for receiving a plurality of digital sensing signalsNumber S_D1To S_DnAnd based on a plurality of digital sensing signals S_D1To S_DnGenerating a plurality of weight signals S_W1To S_WnTo the signal integration circuit 510. Multiple weight signals S_W1To S_WnRespectively corresponding to a plurality of digital sensing signals S_D1To S_Dn。

In some embodiments, the weight circuit 500 is based on a plurality of digital sensing signals S_D1To S_DnDetermine a plurality of weight signals S according to the relative magnitude therebetween_W1To S_WnThereby generating a plurality of weight signals S_W1To S_Wn. In some embodiments, the magnitude of the digital sensing signal is positively correlated to the magnitude of the weight signal.

The operation of the signal integration circuit 510 is similar to that of the signal integration circuit 100 of FIG. 1, with the difference that the signal integration circuit 510 is further based on a plurality of weight signals S_W1To S_WnRespectively combining a plurality of sensing signals to be integrated_D1、S _D2、…、S _D(1+K-1)]、[S _D2、S _D3、…、S _D(2+K-1)]、[S _D3、S _D4、…、S _D(3+K-1)]…, and [ S_D(n-K+1)、S _D(n-K+2)、S _Dn]Performing a signal integration operation.

In some embodiments, the signal integration circuit 510 generates a plurality of integrated sensing signals S by multiplying at least two digital sensing signals of each sensing signal combination to be integrated by corresponding weight signals respectively and then adding the signals_I1To S_I(n-K+1). Combining [ S ] with the sensing signal to be integrated_D1、S _D2、…、S _D(1+K-1)]For example, the digital sensing signal S_D1Corresponding weight signal S_W1(ii) a Digital sensing signal S_D2Corresponding weight signal S_W2(ii) a And, a digital sensing signal S_D(1+K-1)Corresponding weight signalNumber S_W1(1+K-1)And so on. Integrating the sensing signal S_I1Can be expressed as equation (12) below.

S _I1＝S _D1xS _W1+...+S _D(1+K-1)xS _W1(1+K-1) (12)

The rest of the integrated sensing signal S_I2To S_I(n-K+1)Can be obtained based on an equation similar to equation (12). In such an example, the sensing signal S is integrated_I1SNR of_I1Can be expressed as equation (13) below, where in this embodiment, K is 2.

Based on equation (6), equation (13) can be further simplified to equation (14) below.

When equations (11) and (14) are compared, it is clear that the integrated sensing signal S is_I1SNR of_I1Is substantially greater than the digital sensing signal S_D1SNR of_D1. Therefore, the accuracy of the determination result obtained by the proximity event determination circuit 102 based on the integrated sensing signal is higher than that obtained based on the digital sensing signal.

In the embodiment, the weight circuit 500 includes a trial integration circuit 502, an integration judgment circuit 504 and a weight evaluation circuit 506. The way of trying to integrate the signals by the integration circuit 502 is substantially the same as the way of integrating the signals by the signal integration circuit 100 of fig. 2, and therefore the description of trying to integrate the signals by the integration circuit 502 will be omitted.

The pilot integration circuit 502 is used for receivingMultiple digital sensing signals S_D1To S_DnAnd according to a plurality of digital sensing signals S_D1To S_DnGenerating a plurality of combinations of sensing signals [ S ] to be integrated_D1、S _D2、…、S _D(1+K-1)]、[S _D2、S _D3、…、S _D(2+K-1)]、[S _D3、S _D4、…、S _D(3+K-1)]…, and [ S_D(n-K+1)、S _D(n-K+2)、S _Dn]. Multiple sensing signal combination [ S ] to be integrated_D1、S _D2、…、S _D(1+K-1)]、[S _D2、S _D3、…、S _D(2+K-1)]、[S _D3、S _D4、…、S _D(3+K-1)]…, and [ S_D(n-K+1)、S _D(n-K+2)、S _Dn]Respectively corresponding to a plurality of digital sensing signals S_D1To S_Dn. The trial integration circuit 502 is used to add at least two digital sensing signals combined by each sensing signal to be integrated with the same weight, for example, the weights are all 1, to generate a plurality of trial integration results S_T1To S_T(n-K+1). Combining [ S ] with the sensing signal to be integrated_D1、S _D2、…、S _D(1+K-1)]For example, the trial integration circuit 502 combines the sensing signals to be integrated by_D1、S _D2、…、S _D(1+K-1)]Digital sensing signal S_D1、S _D2、…、S _D(1+K-1)The weights 1 are added to generate the trial integration result S_T1And so on.

The integration judgment circuit 504 is coupled to the trial integration circuit 502 for determining a plurality of trial integration results S_T1To S_T(n-K+1)Determining a plurality of digital sensing signals S_D1To S_DnThe relative size therebetween.

The weight evaluation circuit 506 is coupled to the integration judgment circuit 504 for sensing based on a plurality of numbersSignal S_D1To S_DnDetermine a plurality of weight signals S according to the relative magnitude therebetween_W1To S_Wn. In some embodiments, the magnitude of the digital sensing signal is positively correlated to the magnitude of the weight signal. The weight evaluation circuit 506 will evaluate the larger weight signal when the digital sensing signal is larger.

Fig. 8 is a diagram illustrating the digital signal processor 50 of fig. 7 operating under the exemplary operation of fig. 3, wherein K is 2 in this embodiment. Referring to fig. 8, the trial integration circuit 502 receives a plurality of digital sensing signals S_D1To S_D7. The trial integration circuit 502 is based on the digital sensing signal S_D1Generating a combination of sensing signals [ S ] to be integrated_D1、S _D2](ii) a According to the digital sensing signal S_D2Generating a combination of sensing signals [ S ] to be integrated_D2、S _D3](ii) a And according to the digital sensing signal S_D3Generating a combination of sensing signals [ S ] to be integrated_D3、S _D4]And so on.

The trial integration circuit 502 combines the sensing signals to be integrated [ S ]_D1、S _D2]Two digital sensing signals S_D1And S_D2Adding the same weight 1 to generate a trial integration result S_T1(ii) a To-be-integrated sensing signal combination [ S ]_D2、S _D3]Two digital sensing signals S_D2And S_D3Adding the same weight 1 to generate a trial integration result S_T2(ii) a And, combining [ S ] the sensing signals to be integrated_D3、S _D4]Two digital sensing signals S_D3And S_D4Adding the same weight 1 to generate a trial integration result S_T3And so on.

Generally, since the capacitance variation detected by the sensing channel X4 is the largest, the digital sensing signal S corresponding to the sensing channel X4 is_D4And max. Integrating results S in trial_T1To S_T6In (1) because of trial integration result S_T3And S_T4Each including a maximum digital sensing signal S_D4Thus, compared to the result S in trial integration_T1To S_T6The rest of the trial integration results in (1), trial integration result S_T3And S_T4Is the largest.

Integration result S due to maximum trial_T3And S_T4Collectively comprising a digital sense signal S_D4The integration decision circuit 504 can reversely derive the digital sensing signal S_D1To S_D7In the middle, the digital sensing signal S_D4Is the largest. In addition, the integration decision circuit 504 is coupled to correspond to the digital sensing signal S_D4The sensing channel X4 is the center point, and the digital sensing signal S corresponding to the sensing channels X3 and X5 of the adjacent sensing channel X4 is determined_D3And S_D5The second largest, and so on.

A weight evaluation circuit 506 responsive to the digital sensing signal S_D4To a maximum, the digital sensing signal S is evaluated_D4Weight signal S_W4Is at a maximum; in response to a digital sense signal S_D3And S_D5At the second largest, the digital sensing signal S is evaluated_D3And S_D5Weight signal S_W3And S_W5The second largest, and so on. The weight evaluation circuit 506 outputs the weight signal S_W1To S_W7Output to the signal integration circuit 510.

The signal integration circuit 510 combines the sensing signals to be integrated_D1、S _D2]Two digital sensing signals S_D1And S_D2Respectively multiplied by corresponding weight signals S_W1And S_W2Post-adding to generate an integrated sensing signal S_I1；To-be-integrated sensing signal combination [ S ]_D2、S _D3]Two digital sensing signals S_D2And S_D3Respectively multiplied by corresponding weight signals S_W2And S_W3Post-adding to generate an integrated sensing signal S_I2；Andcombining the sensing signals to be integrated [ S ]_D3、S _D4]Two digital sensing signals S_D3And S_D4Respectively multiplied by corresponding weight signals S_W3And S_W4Post-adding to generate an integrated sensing signal S_I3And so on.

Fig. 9 is a block diagram of still another embodiment of the digital signal processor 70 of the present application. Referring to fig. 9, the digital signal processor 70 is similar to the digital signal processor 10 of fig. 2, with the difference that the digital signal processor 70 further includes an activation module 700 and a touch module 702.

The start-up module 700 is coupled to the analog front-end circuit 20 of fig. 1 for receiving a plurality of digital sensing signals S_D1To S_DnAnd according to a plurality of digital sensing signals S_D1To S_DnThe enable signal EN is selectively sent to the signal integration circuit 100 or the touch module 702.

When the signal integration circuit 100 receives the enable signal EN and is enabled in response to the enable signal EN, the signal integration circuit 100 generates a plurality of combinations of the sensing signals [ S ] to be integrated_D1、S _D2、…、S _D(1+K-1)]、[S _D2、S _D3、…、S _D(2+K-1)]、[S _D3、S _D4、…、S _D(3+K-1)]…, and [ S_D(n-K+1)、S _D(n-K+2)、S _Dn]. Alternatively, when the signal integration circuit 100 does not receive the enable signal EN and is thus not enabled, the signal integration circuit 100 does not generate the combination of the sensing signals [ S ] to be integrated_D1、S _D2、…、S _D(1+K-1)]、[S _D2、S _D3、…、S _D(2+K-1)]、 [S _D3、S _D4、…、S _D(3+K-1)]…, and [ S_D(n-K+1)、S _D(n-K+2)、S _Dn]The approach event determination circuit 102 is disabled accordingly.

When the touch module 702 receivesThe touch module 702 is configured to generate a plurality of digital sensing signals S according to the enable signal EN and the enable signal EN_D1To S_DnThe touch of the object 40 to the touch screen 30 is judged.

In some embodiments, the starting module 700 is used for a plurality of digital sensing signals S_D1To S_DnWhen at least one of the signals exceeds a threshold, the touch module 702 is enabled and the signal integration circuit 100 is disabled, and the plurality of digital sensing signals S are applied_D1To S_DnWhen the threshold is not reached, the signal integration circuit 100 is enabled and the touch module 702 is not enabled. In some embodiments, the threshold is a particular value. In some embodiments, the threshold is a particular range of values.

In some embodiments, the start module 700 is further configured to turn on the touch screen 30 when the start module 700 enables the signal integration circuit 100. However, the present application is not limited thereto. In some embodiments, the touch screen 30 may be caused by other modules to illuminate.

In some embodiments, when the start module 700 enables the signal integration circuit 100, the signal integration circuit 100 integrates the plurality of integrated sensing signals S_I1To S_I(n-K+1)Transmitting to a Central Processing Unit (CPU) based on a plurality of integrated sensing signals S_I1To S_I(n-K+1)Determining a plurality of equivalent coordinates respectively corresponding to a plurality of integrated sensing signals S_I1To S_I(n-K+1)。

In some embodiments, the digital signal processor 50 of fig. 7 may also include an activation module 700 and a touch module 702.

In some embodiments, a chip includes the

digital signal processor

10 or 50, for example, the chip may be a semiconductor chip implemented by different processes.

Fig. 10 is a schematic diagram of an embodiment of an electronic device 60 to which a chip 62 including a

digital signal processor

10, 50, or 70 is applied. Referring to fig. 9, the electronic device 60 includes a chip 62 and a display screen assembly 64. The display screen assembly 64 includes the touch screen 30. The electronic device 60 may be any handheld electronic device such as a smart phone, a personal digital assistant, a handheld computer system, or a tablet computer.

The foregoing description has set forth briefly the features of certain embodiments of the present application so that those skilled in the art may more fully appreciate the various aspects of the present disclosure. Those skilled in the art should appreciate that they may readily use the present disclosure as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein. Those skilled in the art should understand that they can still make various changes, substitutions and alterations herein without departing from the spirit and scope of the present disclosure.

Claims

A digital signal processor, coupled to analog front end circuit, analog front end circuit is coupled to the touch-sensitive screen, the touch-sensitive screen includes a plurality of sensing channels, a plurality of sensing channels are output a plurality of analog sensing signals respectively according to the electric capacity variation amount that detects in real time, analog front end circuit is used for right a plurality of analog sensing signals that sensing channels output carry out analog-to-digital conversion in order to produce a plurality of digital sensing signals and correspond a plurality of sensing channels respectively, its characterized in that, digital signal processor is used for based on a plurality of digital sensing signals judge in whether there is the object to be close above the touch-sensitive screen, digital signal processor includes:

a signal integration circuit, coupled to the analog front-end circuit, for receiving the digital sensing signals, generating a plurality of to-be-integrated sensing signal combinations according to the digital sensing signals, and performing a signal integration operation on the to-be-integrated sensing signal combinations to generate a plurality of integrated sensing signals, wherein the number of the to-be-integrated sensing signal combinations is the same as the number of the digital sensing signals, and each of the to-be-integrated sensing signal combinations includes at least two of the digital sensing signals; and

and the proximity event judging circuit is coupled to the signal integration circuit and used for judging whether the object is close to the touch screen or not based on the plurality of integrated sensing signals.
The digital signal processor of claim 1, wherein the at least two digital sensing signals in each combination of sensing signals to be integrated correspond to adjacent at least two sensing channels of the plurality of sensing channels.
The digital signal processor of claim 1, wherein the signal integration circuit generates the plurality of integrated sensing signals by summing the at least two digital sensing signals combined for each sensing signal to be integrated.
The digital signal processor of claim 1, further comprising:

the weight circuit is coupled to the analog front-end circuit and the signal integration circuit, and is configured to receive the plurality of digital sensing signals and generate a plurality of weight signals to the signal integration circuit based on the plurality of digital sensing signals, wherein the plurality of weight signals respectively correspond to the plurality of digital sensing signals.
The digital signal processor of claim 4, wherein the weight circuit determines the plurality of weight signals based on a relative magnitude between the plurality of digital sense signals.
The digital signal processor of claim 5, wherein the signal integration circuit further performs the signal integration operation based on the plurality of weight signals.
The digital signal processor as claimed in claim 6, wherein the signal integration circuit generates the plurality of integrated sensing signals by multiplying the at least two digital sensing signals combined by each sensing signal to be integrated by the corresponding weight signal respectively and then adding the signals.
The digital signal processor of claim 5, wherein each combination of sensing signals to be integrated comprises the same number of digital sensing signals.
The digital signal processor of claim 8, wherein each combination of sensing signals to be integrated is different from each other.
The digital signal processor of claim 9, wherein two of the plurality of combinations of sense signals to be integrated comprise at least one common digital sense signal.
The digital signal processor of claim 4, wherein the weight circuit comprises:

the trial integration circuit is used for receiving the plurality of digital sensing signals, generating a plurality of to-be-integrated sensing signal combinations respectively corresponding to the plurality of digital sensing signals according to the plurality of digital sensing signals, and adding the at least two digital sensing signals of each to-be-integrated sensing signal combination by the same weight to generate a plurality of trial integration results.
The digital signal processor of claim 11, wherein the weight circuit further comprises:

the integration judgment circuit is coupled to the trial integration circuit and used for judging the relative magnitude of the digital sensing signals based on the trial integration results.
The digital signal processor of claim 12, wherein the weight circuit further comprises:

a weight evaluation circuit, coupled to the integration judgment circuit, for determining the weight signals based on the relative magnitudes of the digital sensing signals.
The digital signal processor as claimed in claim 1, wherein the capacitance variation corresponding to the integrated sensing signals is non-gaussian distributed as a whole.
The digital signal processor of claim 1, wherein the signal integration circuit is configured to generate the plurality of combinations of sensing signals to be integrated when enabled, wherein the digital signal processor further comprises:

the touch module is used for judging the touch of the object on the touch screen based on the digital sensing signals when the touch module is enabled; and

and the starting module is coupled with the signal integration circuit and the touch module and used for enabling the touch module and not enabling the signal integration circuit when at least one of the digital sensing signals exceeds a threshold, and enabling the signal integration circuit and not enabling the touch module when none of the digital sensing signals reaches the threshold.
The digital signal processor as claimed in claim 15, wherein when the enabling module enables the signal integration circuit, the enabling module is configured to turn on the touch screen and the signal integration circuit transmits the integrated sensing signals to a central processing unit, wherein the central processing unit determines equivalent coordinates corresponding to the integrated sensing signals based on the integrated sensing signals.
A chip, wherein the chip comprises:

the digital signal processor of any of claims 1-16.
An electronic device, comprising:

the touch screen; and

the chip of claim 17.