KR101063878B1 - Proximity sensor using random algorithm, proximity sensor module and proximity sensing method - Google Patents

Abstract

A proximity sensor using a random algorithm, a proximity sensor module and a proximity sensing method using the same are disclosed. The proximity sensor for detecting the capacitance change of the touch pad, the capacitance of which changes in capacitance when approaching and touching the conductor according to an embodiment of the present invention, the reference clock signal generator for generating a reference clock signal whose frequency can be changed in response to a control signal. A delay sensing unit configured to receive the reference clock signal, detect a change in the capacitance as a delay of the reference clock signal, and output a reference clock delay signal; and a voltage level of the detected voltage in response to the reference clock delay signal When the voltage level is greater than the voltage level, the delay integrating unit outputting the delay integration signal of the first level and the time until the delay integration signal of the first level is generated are checked, and a plurality of delay integration signals of the first level are generated. An average filter unit for calculating an average time value of time is provided.

Description

Proximity sensor using random algorithm and proximity sensor module and proximity sensing method}

The present invention relates to a proximity sensor using a random algorithm, a proximity sensor module using the same, and a proximity sensing method. In particular, a proximity sensor module having a high sensitivity and high sensitivity to noise by applying a random algorithm and an integration algorithm to a proximity sensing method and a proximity sensor module using the same And a proximity sensing method.

At present, the switch used in home appliances, liquid crystal monitors, etc. is being switched from the conventional push switch method to the touch switch method (touch sensor method). The touch switch installs an electrode inside the front cover of the product and touches the electrode part with a finger to sense a change in capacitance induced between the electrode and a person, and the sensing signal is converted into a microprocessor or a microcomputer. It's a way to deliver.

In the touch switch method, a change in capacitance induced between a pre-installed electrode and a person in contact with the electrode is detected, or a change in inductance or impedance is detected. There is a way to detect. However, the touch switch method has a problem in that the touch panel is damaged or malfunctions due to touch pressure when the touch is continued.

As a complementary method, a proximity sensing method has been developed instead of a touch method.

Proximity sensor method is to detect the proximity of the human body or the conductor, a slightly different method than the touch sensor method. The touch sensor method recognizes a contact of an object, but the proximity sensor method recognizes a proximity of a conductor even without contact.

However, the proximity sensor method is difficult to detect the proximity of the conductor because the change of the detection signal for detecting the proximity is very small, and also vulnerable to noise caused by the surrounding environment. If a sensitive sensing circuit is used to recognize the proximity of the conductor, it will react sensitively to the noise around it, making it more susceptible to noise. Conversely, using less sensitive sensing circuits to be more resistant to noise can make proximity sensing difficult.

Therefore, there is a need to develop a proximity sensor that is strong in noise and high in sensitivity.

The technical problem to be achieved by the present invention is to provide a proximity sensor and a proximity sensor module that is resistant to noise and has high sensitivity by using a random algorithm and an integration algorithm.

Another object of the present invention is to provide a proximity sensing method that is resistant to noise and has high sensitivity by using an integration algorithm.

In order to achieve the above technical problem, a proximity sensor for detecting a change in capacitance of a touch pad whose capacitance changes when approaching and touching a conductor according to an embodiment of the present invention is provided.

A reference clock signal generator for generating a reference clock signal whose frequency can be changed in response to a control signal, receiving the reference clock signal, and detecting the change in capacitance as a delay of the reference clock signal to output a reference clock delay signal A delay integrating unit for outputting a delay integrating signal of a first level and a delay integrating signal of the first level when a voltage level of a sensing voltage becomes greater than a voltage level of a reference voltage in response to the reference clock delay signal; And a mean filter section for checking the time until the time lapse and calculating an average time value of the generation times of the plurality of first level delay integration signals.

The average filter unit outputs the average time value generated when the conductor does not approach the touch pad as a first average time value, and the proximity sensor generates a time when the delay integration signal of the first level is generated. The electronic device further includes a detection unit recognizing that the conductor is close to the touch pad when it is faster than the average time value, and recognizing that there is no proximity of the conductor when it is later than the first average time value.

The delay sensing unit generates a reference clock delay signal corresponding to a delay difference between the first signal and the second signal generated in response to the reference clock signal, and when the conductor is close to the touch pad, the second signal is added. A delay is generated to generate the reference clock delay signal in response to a delay difference between the first signal and the second signal.

The delay difference between the first signal and the second signal is detected by a phase detector or a phase-frequency detector to generate the reference clock delay signal.

The delay sensing unit further includes a dummy sensor unit for adjusting the delay of the first signal.

The delay integrating unit outputs the delay integrating signal having the first level when the value of accumulating the sensing voltage is greater than the reference voltage in response to the reference clock delay signal.

The delay sensing unit may include: a first node receiving the reference clock signal; a first delay unit delaying the reference clock signal received from the first node and outputting the first clock signal as a first signal; and in response to a change in the capacitance. A second delay unit for delaying the reference clock signal received from the first node and outputting it as a second signal;

And a reference clock delay signal generator for detecting a phase difference between the first signal and the second signal and outputting the reference clock delay signal.

 The delay integrator is an integrator configured to accumulate voltage levels of a sensing voltage node that is a node that is turned on or turned off in response to the reference clock delay signal to generate the sensing voltage, and a voltage level of the sensing voltage and the reference voltage. Comparing the voltage level and the voltage level of the sensing voltage is greater than the voltage level of the reference voltage includes a comparator for generating a delay integrated signal of the first level and a reset unit for resetting the voltage level of the sensing voltage node.

The reference clock signal generator further includes a bit generator for generating at least one bit or more frequency control signals in response to the control signal and a clock generator for generating the reference clock signal having a variable frequency in response to the frequency control signal. do.

The detection unit recognizes that the conductor is close to the touch pad when the delay integration signal of the first level occurs within a predetermined threshold time, and generates an error when the delay integration signal of the first level occurs later than the threshold time. Recognize.

According to another aspect of the present invention for achieving the technical problem, a touch panel and a frequency changeable reference clock signal coupled with a plurality of touch pads of which capacitance changes in proximity and touch of a conductor are received, and the capacitance Detecting the delay of the reference clock signal according to the change and integrating the detection voltage in response to the detected delay of the reference clock signal, the time when the voltage level of the detection voltage is greater than the voltage level of the reference voltage than the first average time value As early as possible, the touch panel includes a controller IC which recognizes that the conductor is in proximity or touch.

The controller IC receives the reference clock signal, detects a delay of the reference clock signal according to a change in the capacitance, and integrates a sensing voltage in response to the detected delay of the reference clock signal to thereby detect the voltage of the detection voltage. When the level is greater than the voltage level of the reference voltage, the delay integrated signal of the first level is generated, and the proximity sensor for checking the time until the delay integrated signal of the first level is generated and the delay integrated signal are the first integrated signal. The detection unit recognizes that the conductor is close or touched to the touch pad when it occurs earlier than the average time value, and recognizes that there is no proximity of the conductor when the delay integrated signal of the first level occurs later than the first average time value. It is provided.

The proximity sensor includes a reference clock signal generation unit for generating the reference clock signal whose frequency can be changed in response to a control signal, the reference clock signal, and a reference clock signal delayed in response to a change in capacitance. A delay integrating unit for outputting a clock delay signal, a delay integrating unit for outputting a delay integration signal of the first level, and a delay integrating signal of the first level when the detection voltage is greater than the reference voltage in response to the reference clock delay signal; Confirm the time until is generated, calculate the average time value of the time of occurrence of the delay integrated signals of the plurality of first levels, and calculate the average time value generated when the conductor does not approach the touch pad. An average filter portion for outputting as one average time value is provided.

The delay sensing unit generates a reference clock delay signal corresponding to a delay difference between the first signal and the second signal generated in response to the reference clock signal, and when the conductor is close to the touch pad, the second signal is added. A delay is generated to generate the reference clock delay signal in response to a delay difference between the first signal and the second signal.

The delay difference between the first signal and the second signal is detected by a phase detector or a phase-frequency detector to generate the reference clock delay signal.

Proximity sensing method according to another embodiment of the present invention for achieving the above technical problem, detecting the capacitance change of the touch pad, the capacitance changes during proximity and touch of the conductor, receiving a reference clock signal, Detecting a change in capacitance as a delay of the reference clock signal and outputting a reference clock delay signal; and when a value in which a sense voltage is integrated in response to the reference clock delay signal is greater than a reference voltage, a delay integrated signal of a first level is output. Outputting and recognizing that the conductor is close to the touch pad when the delay integrated signal of the first level occurs earlier than the first average time value, and conducting the conductor when the delay integrated signal occurs later than the first average time value. Recognizing that there is no proximity of.

Proximity sensor, proximity sensor module and proximity sensing method according to an embodiment of the present invention is very resistant to the surrounding noise by using a digital sensing method, fine detection is possible according to the proximity of the conductor by applying a random algorithm and integration algorithm. There is a strong advantage against external noise.

In addition, since the reference voltage or the reference clock signals used in the proximity sensor are not a reference for detecting the proximity of the conductor, even if these values are changed, they do not affect the detection of proximity and are insensitive to changes in the internal circuit. The delay circuit is not a high impedance circuit and therefore is insensitive to external and internal noise.

In addition, the amount of delay of the reference clock signal can be adjusted using the dummy sensor, thereby controlling the sensitivity of the proximity sensor and responding to environmental changes.

In order to fully understand the present invention, operational advantages of the present invention, and objects achieved by the practice of the present invention for achieving the above technical problem, reference should be made to the accompanying drawings which illustrate preferred embodiments of the present invention. do.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Like reference numerals in the drawings denote like elements.

1 is a conceptual diagram illustrating a structure of a proximity sensor according to an embodiment of the present invention.

FIG. 2 is a circuit diagram of a proximity sensor corresponding to the conceptual diagram of the proximity sensor of FIG. 1.

1 and 2, the proximity sensor 100 according to an exemplary embodiment of the present invention relates to a proximity sensor that detects a change in capacitance of a touch pad TP in which capacitance changes during proximity and touch of a conductor. .

The proximity sensor 100 includes a reference clock signal generator 101, a delay sensing unit 110, a delay integration unit 120, and an average filter unit AF.

The reference clock signal generator 101 generates a reference clock signal CLK whose frequency can be changed in response to the control signal CTL. The delay sensing unit 110 receives the reference clock signal CLK, detects the change in capacitance as a delay of the reference clock signal CLK, and outputs the reference clock delay signal DCLK. The delay integrating unit 120 outputs the delay integrating signal SIG of the first level when the level of the sensing voltage SV becomes greater than the level of the reference voltage VREF in response to the reference clock delay signal DCLK. Here, the first level is regarded as a high level for convenience of description, but is not limited thereto. The first level may be a low level depending on the configuration of the circuit.

The average filter AF checks the time until the delay integrated signal SIG of the first level is generated and calculates an average time value of the generation times of the delay integrated signals SIG of the plurality of first levels. .

The average filter unit AF outputs an average time value generated when the conductor does not approach the touch pad TP as a first average time value. In addition, the proximity sensor 100 recognizes that the conductor is close to the touch pad TP when the time at which the delay integrated signal SIG of the first level occurs is earlier than the first average time value, and the first average time value. It is further provided with a detection unit (DDL) for recognizing that there is no proximity of the conductor. The detection unit DDL is composed of digital logic.

1 and 2, a touch pad TP is disclosed for convenience of understanding. The touch pad TP has a structure in which capacitance changes when a conductor such as a human body is in close proximity, and a detailed description thereof will be omitted since the structure can be understood by those skilled in the art. The touch panel is formed by a plurality of touch pads TP. Usually, since the touch pad TP constitutes a touch panel, the touch pad is formed on the touch panel side, and the proximity sensor 100 recognizes a change in capacitance of the touch pad TP to detect a touch or proximity position. Is formed). The touch sensor module is composed of a touch panel and a controller IC as described above. This will be described later.

The reference clock signal generator 101 will be described in more detail. The reference clock signal generation unit 101 has a variable frequency in response to the bit generation unit RBG and the frequency control signal FCTL generating at least one bit or more of the frequency control signal FCTL in response to the control signal CTL. And a clock generator DCO for generating the reference clock signal CLK.

The bit generator RBG randomly generates a frequency control signal FCTL in response to a control signal input from the outside as a random bit generator. The control signal CTL may vary and may be input by an external user or automatically generated. The frequency control signal FCTL is a signal of at least one bit or more, and for example, a four-bit signal is randomly generated as 1011, 1000, 0101, etc. in response to the control signal CTL.

The clock generator DCO may be configured as a digital controlled oscillator, and the frequency of the reference clock signal CLK generated in response to the frequency control signal FCTL is changed. That is, the frequency of the reference clock signal CLK generated when the frequency control signal FCTL is 1011 and 1000 is different. Thus, as shown in FIG. 3, the period of the reference clock signal CLK may be randomly changed.

The reference clock signal generator 101 is configured with circuits for generating the reference voltage VREF. Since the reference voltage and the reference clock signal are not used as a reference for detecting the proximity of the conductor in the embodiment of the present invention, even if a change in the external environment occurs, the sensitivity of the proximity sensor 100 is not affected. Therefore, the proximity sensor 100 according to the embodiment of the present invention has an advantage of not requiring the sophisticated reference voltage or the reference clock signal CLK.

When the reference clock signal CLK is delayed due to a change in capacitance, the delay sensing unit 110 compares the delayed reference clock signal CLK with the original reference clock signal CLK to determine the reference clock delay signal DCLK. Will occur). The delay integrating unit 120 integrates the sensing voltage SV in response to the reference clock delay signal DCLK, and when the level of the sensing voltage SV is greater than the level of the reference voltage VREF, the delay integrating signal SIG is integrated. Occurs. That is, there is a difference in the time at which the delay integrated signal SIG is generated when there is no proximity between the conductors, and the difference is detected by the detector DDL to recognize that there is a proximity of the conductors.

In more detail, the delay sensing unit 110 generates a first signal S1 and a second signal S2 having a delay in response to the reference clock signal CLK.

The reference clock delay signal DCLK is generated in response to the delay difference between the first signal S1 and the second signal S2.

The delay difference between the first signal S1 and the second signal S2 is detected by a phase detector or a phase-frequency detector to generate a reference clock delay signal DCLK. As an example, in FIG. 2, the reference clock delay signal DCLK is shown to be generated by the exclusive logic sum XOR of the first signal S1 and the second signal S2, which is only one example. It doesn't happen.

The second signal S2 has an additional delay in response to a change in capacitance generated by the conductor approaching the touch pad TP. Referring to FIG. 2, the delay sensing unit 110 delays a first node NA that receives a reference clock signal CLK, and a reference clock signal CLK received from the first node NA to delay the first signal. The first delay unit 111 outputting as S1 and the second delaying unit outputs the reference clock signal CLK received from the first node NA in response to the change in capacitance, and outputs it as the second signal S2. The delay unit 113 and the reference clock delay signal generator 115 for detecting a delay difference between the first signal S1 and the second signal S2 and outputting the reference clock delay signal DCLK are provided. The reference clock delay signal generator 115 may be configured as a phase detector or a phase frequency detector. In FIG. 2, an exclusive logic element is used for convenience of description. As shown in FIG. 2, the first delay unit 111 and the second delay unit 113 may use a plurality of delay buffers, and the first signal S1 and the first delay unit 111 may not be close to the touch pad TP. The delay amount of the two signals S2 causes a constant difference.

The second delay unit 113 is connected to the touch pad TP by the bonding pad 117. Therefore, when the conductor of the touch pad TP is changed to change the capacitance of the touch pad TP (exactly, the capacitance is increased), the delay of the second signal S2 becomes larger.

The delay sensing unit 110 further includes a dummy sensor unit 130 connected to the first delay unit 111 to adjust the delay of the first signal S1. The dummy sensor unit 130 adjusts the delay of the first delay unit 111 by compensating for parasitic capacitance such as a bonding pad 117 connected to the second delay unit 113. The dummy sensor unit 130 may include a plurality of capacitors and switches connected to the capacitors as shown in FIG. 1. By connecting the switches, the capacitance can be increased or decreased, thereby adjusting the delay amount of the first signal S1.

By adjusting the dummy sensor unit 130, the amount of delay of the reference clock signal CLK may be adjusted, thereby adjusting sensitivity and changing the environment. In addition, when the proximity sensor 100 is applied to a module or a product, the operating environment varies greatly according to the environment of each product. In order to respond to such a change, the reference clock signal CLK is used by using the dummy sensor unit 130. By adjusting the delay amount, the operation can be performed in various environments.

This operation will be understood by those skilled in the art, and thus a detailed description thereof will be omitted.

The delay integrating unit 120 outputs the delay integrating signal SIG to the first level when the value of accumulating the sensing voltage SV in response to the reference clock delay signal DCLK is greater than the reference voltage VREF. In detail, the delay integrator 120 accumulates voltage levels of the sensing voltage node SVN, which is a node that is turned on or turned off in response to the reference clock delay signal DCLK to generate the sensing voltage SV. The voltage level of the detection voltage SV and the voltage level of the reference voltage VREF are compared with each other and the delay level integration of the first level is performed when the voltage level of the detection voltage SV is greater than the voltage level of the reference voltage VREF. Comparing unit 123 for generating signal SIG and reset unit NTR2 for resetting the voltage level of sensing voltage node SVN.

As illustrated in FIG. 2, the integrating unit 121 is connected to a current source IREF connected to a power supply voltage VCC, and a second stage is connected to a capacitor C connected to ground, and a reference clock delay signal. The transistor NTR1 is turned on or off by the DCLK. The connection node between the second terminal of the transistor NTR1 and the capacitor C is a sensing voltage node SVN for generating the sensing voltage SV. Instead of the transistor NTR1, a switch for turning on or turning off may be connected and used.

The comparator 123 includes a comparator that receives the sensing voltage SV and the reference voltage VREF. In addition, the reset unit NTR2 includes a transistor NTR2 connected between the sensing voltage node SVN and the ground and turned on or off in response to the reset signal RST. The reset signal RST is generated every reference time TRST to turn on the transistor NTR2 to reset the sensing voltage node SVN to the ground voltage.

Such a circuit configuration can be understood by those skilled in the art, and it can be understood that modifications can be made.

The average filter unit AF checks the time until the delay integration signal SIG of the first level is generated in the delay integration unit 120. To check the time, a timer (not shown) and a main clock (not shown) inside the proximity sensor are used. That is, the number of main clocks is counted until the delay integrated signal SIG of the first level is generated, and the time is confirmed. The average filter AF calculates an average time value of generation times of the delay integrated signals SIG of the plurality of first levels. In particular, the average filter unit AF outputs the average time value AVT generated when the conductor does not approach the touch pad TP as the first average time value TH. The average filter unit AF may check the generation times of the first-level delay integrated signal SIG when the conductor is not close to the touch pad TP, and obtain the average time value AVT. The average time value AVT is stored in the detector DDL as the first average time value. Then, it is compared with the generation time of the delay integrated signal SIG of the first level when the conductor approaches the touch pad TP.

Considering the case where the conductor does not approach the touch pad TP, since the frequency of the reference clock signal CLK changes randomly, the generation time of the delay integrated signal SIG having the first level also changes randomly. do. However, if one repeats the method of selecting one of the natural numbers from 1 to 100 and averaging the average, the average value is close to 50, which is an intermediate value between 1 and 100. Similarly, if the frequency of the reference clock signal CLK is changed randomly, the generation time of the delay integrated signal SIG having the first level is continuously changed, but if the average of these times is continuously averaged, the average time value (AVT) converges at a constant time value. This is the principle of the random algorithm.

The change in the frequency of the reference clock signal CLK has a similar effect to the increase in the noise of the surrounding environment in the proximity sensor, but in this way, the reference clock signal in which the frequency is changed using the average filter unit AF. The average time value AVT, which is less susceptible to the effects of noise, can be obtained by averaging several times the generation time of the first-level delay integrated signal SIG obtained through the integration algorithm from CLK.

Therefore, the average time value AVT is stored in the detection unit DDL as a first average time value, and the time at which a later-input delay integrated signal SIG of the first level is generated is compared with the first average time value. It may be determined whether the proximity of the conductor occurs to the touch pad TP.

3 is a timing diagram illustrating the operation of a proximity sensor when the conductor is not close to the touch pad.

4 is a timing diagram illustrating the operation of the proximity sensor when the conductor is close to the touch pad.

First, referring to FIG. 3, a reference clock signal CLK having a variable frequency is input to the delay sensing unit 110. 3, it can be seen that the frequency of the reference clock signal CLK changes randomly. The reference clock signal CLK is delayed by a predetermined time to generate the first signal S1. The first delay unit 111 has a plurality of buffers and may delay the reference clock signal CLK as desired. When the conductor is not close to the touch pad TP, the second signal S2 is also delayed by a predetermined time than the reference clock signal CLK, and is delayed more than the delay of the first signal S1 due to parasitic resistance. do. Then, the reference clock delay signal generator 115 generates the reference clock delay signal DCLK as shown in FIG. 3.

The reference clock delay signal DCLK is generated at a high level every predetermined time, and whenever the reference clock delay signal DCLK is at a high level, the transistor NTR1 is turned on so that the voltage level of the sensing voltage SV is as shown in FIG. 3. It accumulates little by little and rises. Then, when the voltage level of the sensing voltage SV becomes greater than the voltage level of the reference voltage VREF, the comparator 123 generates the delay integration signal SIG at a first level, that is, at a high level.

The average filter AF checks the time TH at which the delay integrated signal SIG is generated at a high level as described above, calculates the average, generates an average time value AVT, and transmits the average time value AVT to the detector DDL. do. The detector DDL stores the average time value AVT as a first average time value. Here, depending on the circuit configuration, the low level and the high level may be changed, and the embodiment of the present invention is not limited to such a logic value.

Referring to FIG. 4, the reference clock signal CLK having a change in frequency is input to the delay sensing unit 110. 4, it can be seen that the frequency of the reference clock signal CLK changes randomly. The reference clock signal CLK is delayed to generate the first signal S1. When the conductor is close to the touch pad TP, the capacitance of the touch pad TP changes, and the change of the capacitance of the touch pad TP delays the second signal S2 than the reference clock signal CLK. . In this case, the amount of delay is greater than the amount of delay of the second signal S2 in FIG. 3.

The reference clock delay signal generator 115 detects a phase difference between the first signal S1 and the second signal S2 to generate the reference clock delay signal DCLK. For example, an exclusive logic sum of the first signal S1 and the second signal S2 generates a reference clock delay signal DCLK as shown in FIG. 4. Since the first delay unit 111 and the second delay unit 113 are not circuits having a high impedance, they are insensitive to external or internal noise.

During the period in which the reference clock delay signal DCLK occurs at a high level, the transistor NTR1 of the integrating unit 121 is turned on and the sensing voltage SV of the sensing voltage node SVN is constant by the capacitor C. Rise to the level. While the high level section of the reference clock delay signal DCLK is repeated, the voltage level of the sensing voltage SV continues to rise as shown in FIG. Then, a time point TH becomes greater than the voltage level of the reference voltage VREF at any moment, and the comparator 123 generates the delay integration signal SIG at a high level at this time point TH. However, the reference clock delay signal DCLK takes a longer time when the conductor is closer to the touch pad TP than when the conductor is not near the touch pad TP. The time for accumulating the voltage level is fast, and the time for generating the delay integrated signal SIG at a high level is also faster than the first average time value.

The detector DDL recognizes that the conductor is close to the touch pad TP when the time TH at which the delay integrated signal SIG is generated at the first level is earlier than the first average time value.

Subsequently, the reset part NTR2 resets the sensing voltage SV by the reset signal RST, and the sensing of the touch pad TP is started again.

As described above, when the time TH at which the delay integrated signal SIG occurs at a high level (or at a low level according to a circuit configuration) is earlier than the first average time value, the detector DDL is not close to the conductor. Since the first average time value is a value calculated by a random algorithm and an integration algorithm, the first average time value may be stronger to environmental changes or noise than to measure the sensing of the proximity sensor only by the integration algorithm without a random algorithm.

Also, if the delay integration signal SIG occurs within a predetermined threshold time, the detection unit DDL recognizes that the conductor is close to the touch pad TP. If the delay integration signal SIG occurs later than the threshold time, the detection unit DDL generates an error. I can recognize it. As such, if the delay integrated signal SIG occurs earlier than the first average time value, the delay integrated signal SIG may be regarded as a proximity of a conductor. When the delay integrated signal SIG is generated at a high level later than the threshold time TH, the proximity operation may be recognized as an error operation, thereby further increasing the accuracy of the proximity sensor 100.

5 is a view illustrating a proximity sensor module according to another embodiment of the present invention.

The proximity sensor module 500 according to another embodiment of the present invention includes a touch panel 510 in which a plurality of touch pads TP whose capacitance is changed in proximity and touch of a conductor and a reference clock signal whose frequency is changeable ( Receives CLK, detects the delay of the reference clock signal CLK according to the change in capacitance, and integrates the detection voltage SV in response to the detected delay of the reference clock signal CLK to detect the detection voltage SV. The controller IC 520 recognizes that the conductor is close to or touched on the touch panel 510 when the time when the voltage level becomes greater than the voltage level of the reference voltage VREF is faster than the first average time value.

The controller IC 520 receives the reference clock signal CLK, detects a delay of the reference clock signal CLK according to the change in capacitance, and applies the detection voltage SV in response to the detected delay of the reference clock signal. When the voltage level of the detection voltage SV becomes greater than the voltage level of the reference voltage by integrating, the proximity sensor 100 and the delay integration signal SIG generating the delay integration signal SIG of the first level are larger than the first average time value. The detection unit recognizes that the conductor is close or touched to the touch pad TP when it occurs early, and recognizes that there is no proximity of the conductor when the delay integrated signal SIG of the first level occurs later than the first average time value. DDL).

The proximity sensor module 500 having such a configuration includes a touch panel 510 and a controller IC 520, and the controller IC 520 further includes a proximity sensor 100 and a detector DDL. Since the proximity sensor 100 has the same operation and structure as described above, a detailed description thereof will be omitted.

6 is a flowchart according to another embodiment of the present invention.

Proximity sensing method 600 according to an embodiment of the present invention for achieving the above another technical problem, step 610 of detecting the capacitance change of the touch pad that changes the capacitance when the proximity and the touch of the conductor, the reference clock signal And receiving a change in the capacitance as a delay of the reference clock signal and outputting a reference clock delay signal. In step 620, when the detected voltage is greater than the reference voltage in response to the reference clock delay signal, the delay integration of the first level is performed. In step 630 and 640 for outputting a signal, and if the delay integrated signal is faster than the first average time value, the conductor is recognized as being close to the touch pad, and if the delay integrated signal occurs later than the first average time value, It has 650 steps to recognize that there is no proximity.

Since the proximity sensing method 600 is similar to the operation of the proximity sensor 100 as a sensing method using the proximity sensor 100 of FIG. 2, a detailed description thereof will be omitted.

As described above, optimal embodiments have been disclosed in the drawings and the specification. Although specific terms have been used herein, they are used only for the purpose of describing the present invention and are not intended to limit the scope of the invention as defined in the claims or the claims. Therefore, those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

1 is a conceptual diagram illustrating a structure of a proximity sensor according to an embodiment of the present invention.

FIG. 2 is a circuit diagram of a proximity sensor corresponding to the conceptual diagram of the proximity sensor of FIG. 1.

3 is a timing diagram illustrating the operation of a proximity sensor when the conductor is not close to the touch pad.

4 is a timing diagram illustrating the operation of the proximity sensor when the conductor is close to the touch pad.

5 is a view illustrating a proximity sensor module according to another embodiment of the present invention.

6 is a flowchart according to another embodiment of the present invention.

Claims (16)

In the proximity sensor for detecting the change in capacitance of the touch pad, the capacitance of the change in proximity and touch of the conductor, A reference clock signal generator for generating a reference clock signal whose frequency can be changed in response to the control signal; A delay sensing unit configured to receive the reference clock signal, detect a change in the capacitance as a delay of the reference clock signal, and output a reference clock delay signal; A delay integrator for outputting a delay integrated signal of a first level when the voltage level of the sensed voltage becomes greater than the voltage level of the reference voltage in response to the reference clock delay signal; And And an average filter unit for checking a time until the delay integrated signal of the first level is generated and calculating an average time value of the generation times of the plurality of first level delay integrated signals. The method of claim 1, wherein the average filter unit, Outputting the average time value generated when the conductor does not approach the touch pad as a first average time value, The proximity sensor, A detection unit for recognizing that the conductor is close to the touch pad when the time for generating the delay integrated signal of the first level is earlier than the first average time value; Proximity sensor characterized in that it further comprises. The method of claim 2, wherein the delay sensing unit, A reference clock delay signal corresponding to a delay difference between the first signal and the second signal generated in response to the reference clock signal is generated. When the conductor is close to the touch pad, the second signal has an additional delay. And the reference clock delay signal is generated in response to a delay difference between the first signal and the second signal. The method of claim 3, wherein the delay difference between the first signal and the second signal is detected by a phase detector or a phase-frequency detector to generate the reference clock delay signal. Proximity sensor. The method of claim 3, wherein the delay sensing unit, Proximity sensor further comprises a dummy sensor for adjusting the delay of the first signal. The method of claim 2, wherein the delay integration unit, And the delay integrated signal of the first level is output when the value of accumulating the detection voltage is greater than the reference voltage in response to the reference clock delay signal. The method of claim 2, wherein the delay sensing unit, A first node receiving the reference clock signal; A first delay unit which delays the reference clock signal received from the first node and outputs the first clock signal as a first signal; A second delay unit for delaying and outputting the reference clock signal received from the first node in response to the change in capacitance; And And a reference clock delay signal generator for detecting a phase difference between the first signal and the second signal and outputting the reference clock delay signal. The method of claim 2, wherein the delay integration unit, An integrating unit accumulating voltage levels of a sensing voltage node, the node being turned on or off in response to the reference clock delay signal to generate the sensing voltage; A comparison unit comparing the voltage level of the sensing voltage with the voltage level of the reference voltage to generate a delay integration signal of the first level when the voltage level of the sensing voltage is greater than the voltage level of the reference voltage; And And a reset unit for resetting the voltage level of the sensing voltage node. The method of claim 2, wherein the reference clock signal generation unit, A bit generator for generating at least one bit or more frequency control signal in response to the control signal; And And a clock generator for generating the reference clock signal whose frequency is variable in response to the frequency control signal. The method of claim 2, wherein the detection unit, When the delay integration signal of the first level occurs within a predetermined threshold time, the conductor is recognized as being close to the touch pad, and when the delay integration signal of the first level occurs later than the threshold time, it is recognized as an error. Proximity sensor. A touch panel in which a plurality of touch pads whose capacitance changes in proximity and touch of a conductor are coupled; And Generating a reference clock signal whose frequency can be changed in response to a control signal, detecting a delay of the reference clock signal according to a change in the capacitance, and integrating the sensed voltage in response to the detected delay of the reference clock signal And a controller IC for recognizing that the conductor is in proximity or touch when the time when the voltage level of the voltage is greater than the voltage level of the reference voltage is faster than the first average time value. The method of claim 11, wherein the controller IC, The reference clock signal is generated in response to the control signal, detects a delay of the reference clock signal according to the change of the capacitance, and integrates a detection voltage in response to the detected delay of the reference clock signal to generate the reference clock signal. A proximity sensor generating a delay integration signal of a first level when the voltage level is greater than a voltage level of a reference voltage, and checking a time until the delay integration signal of the first level is generated; And When the delay integration signal is generated earlier than the first average time value, it is recognized that the conductor is close to or touched by the touch pad. When the delay integration signal of the first level occurs later than the first average time value, Proximity sensor module comprising a detection unit for recognizing that there is no proximity of the conductor. The method of claim 12, wherein the proximity sensor, A reference clock signal generator for generating the reference clock signal whose frequency can be changed in response to the control signal; A delay sensing unit configured to output a reference clock delay signal by comparing the reference clock signal with a reference clock signal delayed in response to a change in the capacitance; A delay integrator configured to output a delay integrated signal of the first level when the sensed voltage is greater than the reference voltage in response to the reference clock delay signal; And Check the time until the delay integrated signal of the first level is generated, calculate the average time value of the generation time of the delay integrated signal of a plurality of first levels, when the conductor does not approach the touch pad And a mean filter unit for outputting the generated mean time value as a first mean time value. The method of claim 13, wherein the delay sensing unit, A reference clock delay signal corresponding to a delay difference between the first signal and the second signal generated in response to the reference clock signal is generated. When the conductor is close to the touch pad, the second signal has an additional delay. And the reference clock delay signal is generated in response to a delay difference between the first signal and the second signal. 15. The method of claim 14, wherein the delay difference between the first signal and the second signal is detected by a phase detector or a phase-frequency detector to generate the reference clock delay signal. Proximity sensor module. Detecting a change in capacitance of the touch pad, the capacitance of which changes in proximity and touch of the conductor; Receiving a reference clock signal, sensing the change in capacitance as a delay of the reference clock signal, and outputting a reference clock delay signal; Outputting a delay integrated signal having a first level when a value in which a sense voltage is integrated is greater than a reference voltage in response to the reference clock delay signal; And When the delay integrated signal of the first level occurs earlier than the first average time value, the conductor is recognized as being close to the touch pad. When the delay integrated signal occurs later than the first average time value, there is no proximity of the conductor. Proximity sensing method using a proximity sensor characterized in that it comprises a step of recognizing.

Images