Moisture detection circuit and method for serial bus connector

Abstract

The present disclosure provides a moisture detection circuit for a serial bus connector, the circuit detecting moisture attached to a terminal of the serial bus connector, comprising: a current digital-to-analog converter, a terminal for receiving a first digital signal indicating a current reference value and outputting a current in an analog form having a magnitude corresponding to the first digital signal to the serial bus connector; the voltage digital-to-analog converter is used for receiving a second digital signal for indicating a voltage reference value and outputting an analog voltage corresponding to the second digital signal; the comparator is used for comparing the voltage of the terminal with the voltage output by the voltage digital-to-analog converter; and a controller for providing a first digital signal indicating the current reference value to the current digital-to-analog converter, providing a second digital signal indicating the voltage reference value to the voltage digital-to-analog converter, and determining whether moisture adheres to the terminal based on a comparison result of the comparator.

Description

[0001] CROSS REFERENCE TO RELATED APPLICATIONS This application claims priority to Korean Patent Application No. 10-2023-0171339, filed on November 30, 2023, which is incorporated herein by reference for all purposes as if fully set forth herein. Technical Field

[0002] The invention relates to a moisture detection circuit and method, which are used to detect whether a serial bus connector such as a USB-C has moisture attached thereto. Background Art

[0003] Some electronic devices communicate or supply power to external electronic devices via cables connected to connectors. If foreign matter such as moisture enters the connector, some terminals may short-circuit, corrode, or break, which may cause excessive power consumption in some cases, so it is necessary to detect whether moisture has entered the connector. In addition, when moisture is detected entering the connector, it should not be confused with the situation where a normal accessory is attached, so it is preferable to be able to determine whether a normal accessory is attached. Summary of the invention

[0004] Technical issues to be solved A technical problem to be solved by the present invention is to provide a circuit and a method, which can determine whether a serial bus connector is attached with moisture or is a normal accessory through a simple structure.

[0005] Another technical problem to be solved by the present invention is to reduce the area occupied by a semiconductor chip and the power consumption when realizing a circuit capable of determining whether a serial bus connector has moisture attached thereto or is a normal accessory.

[0006] The technical issues of the present invention are not limited to the above-mentioned issues, and may include other technical issues not mentioned herein.

[0007] Technical Solution In one aspect of the present invention, a moisture detection circuit for a serial bus connector, which detects moisture attached to a terminal of the serial bus connector, includes: a current digital-to-analog converter, which receives a first digital signal indicating a current reference value and outputs a current in an analog form corresponding to the first digital signal to the terminal of the serial bus connector; a voltage digital-to-analog converter, which receives a second digital signal indicating a voltage reference value and outputs a voltage in an analog form corresponding to the second digital signal; a comparator, which compares the voltage of the terminal with the analog form of the voltage output by the voltage digital-to-analog converter; and a controller, which provides the first digital signal indicating the current reference value to the current digital-to-analog converter, provides the second digital signal indicating the voltage reference value to the voltage digital-to-analog converter, and determines whether moisture is attached to the terminal based on the comparison result of the comparator.

[0008] In the moisture detection circuit for a serial bus connector, the current digital-to-analog converter can output a current of a first current reference value in a first time period and a second time period, and output a current of a second current reference value in a third time period and a fourth time period; the voltage digital-to-analog converter can output a voltage of a first voltage reference value in the first time period and the third time period, and output a voltage of a second voltage reference value in the second time period and the fourth time period; the comparator can compare the terminal voltage with the analog form of the voltage output by the voltage digital-to-analog converter in each of the first time period to the fourth time period; the controller can determine whether moisture is attached to the terminal based on the comparison results of the comparator in the first time period to the fourth time period, wherein the time sequence of the first time period to the fourth time period can be set arbitrarily.

[0009] In the moisture detection circuit for a serial bus connector, the controller determines that moisture is attached to the terminal when the following conditions are met: the first current reference value is less than the second current reference value, the first voltage reference value is greater than the second voltage reference value, the terminal voltage in the first time period is less than the first voltage reference value, the terminal voltage in the second time period is greater than the second voltage reference value, the terminal voltage in the third time period is greater than the first voltage reference value, and the terminal voltage in the fourth time period is greater than the second voltage reference value.

[0010] In the moisture detection circuit for the serial bus connector, when the following conditions are met, the controller can determine that a normal accessory is installed at the terminal: the first current reference value is less than the second current reference value, the first voltage reference value is greater than the second voltage reference value, the terminal voltage in the first time period is less than the first voltage reference value, the terminal voltage in the second time period is less than the second voltage reference value, the terminal voltage in the third time period is less than the first voltage reference value, and the terminal voltage in the fourth time period is greater than the second voltage reference value.

[0011] In the moisture detection circuit for a serial bus connector, the current digital-to-analog converter may be a 1-bit digital-to-analog converter that can selectively output a current of a first current reference value and a current of a second current reference value, and the voltage digital-to-analog converter may be a 1-bit digital-to-analog converter that can selectively output a voltage of a first voltage reference value and a voltage of a second voltage reference value.

[0012] The moisture detection circuit for the serial bus connector may also include an edge detector, which detects the rising edge or falling edge of the signal provided by the main controller to the terminal to generate an enable signal, and provides the enable signal to the controller.

[0013] In the moisture detection circuit for a serial bus connector, the controller may start a moisture detection action based on the enable signal output by the edge detector.

[0014] In the moisture detection circuit for the serial bus connector, if it is determined that moisture is attached to the terminal, the controller may disconnect the terminal connection switch connecting the main controller and the terminal.

[0015] In another aspect of the present invention, a moisture detection method for a serial bus connector is performed with the aid of a moisture detection circuit for a serial bus connector, comprising: a first time period comparison step, in a state where a current of a first current reference value is connected to a terminal of the connector, comparing a terminal voltage at the terminal with a first voltage reference value; a second time period comparison step, in a state where a current of the first current reference value is connected to the terminal, comparing the terminal voltage with a second voltage reference value; a third time period comparison step, in a state where a current of the second current reference value is connected to the terminal, comparing the terminal voltage with the first voltage reference value; a fourth time period comparison step, in a state where a current of the second current reference value is connected to the terminal, comparing the terminal voltage with the second voltage reference value; and a step of judging whether moisture is attached to the terminal based on the comparison results of the first time period comparison step to the fourth time period comparison step.

[0016] In the moisture detection method for a serial bus connector, when the following conditions are met, it can be determined that moisture is attached to the terminal: the first current reference value is less than the second current reference value, the first voltage reference value is greater than the second voltage reference value, the terminal voltage in the first time period comparison step is less than the first voltage reference value, the terminal voltage in the second time period comparison step is greater than the second voltage reference value, the terminal voltage in the third time period comparison step is greater than the first voltage reference value, and the terminal voltage in the fourth time period comparison step is greater than the second voltage reference value.

[0017] In the moisture detection method for a serial bus connector, when the following conditions are met, it can be determined that the terminal is equipped with normal accessories: the first current reference value is less than the second current reference value, the first voltage reference value is greater than the second voltage reference value, when the terminal voltage in the first time period comparison step is less than the first voltage reference value, the terminal voltage in the second time period comparison step is less than the second voltage reference value, the terminal voltage in the third time period comparison step is less than the first voltage reference value, and the terminal voltage in the fourth time period comparison step is greater than the second voltage reference value.

[0018] In the moisture detection method for a serial bus connector, the moisture detection method may be started based on a rising edge or a falling edge of a signal provided by a main controller to a terminal of the serial bus connector.

[0019] Effects of the Invention According to an embodiment of the present invention, a simple circuit can be implemented while determining whether the serial bus connector is wet or in good condition.

[0020] According to an embodiment of the present invention, when a circuit capable of determining whether a serial bus connector is attached with moisture or is a normal accessory is implemented, the area occupied on a semiconductor chip and the power consumption can be reduced.

[0021] The effects of the present invention are not limited to the above-mentioned effects, and may include other various effects not mentioned in this specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings, which are included in this application to provide a further understanding of the invention and constitute a part of this application, show detailed descriptions and embodiments of the invention to explain the principles of the invention.

[0023] Figure 1 A block diagram of a moisture detection circuit according to an embodiment of the present invention is shown.

[0024] Figure 21 is a waveform diagram exemplarily illustrating an operation of detecting moisture adhering to a serial bus connector according to an embodiment of the present invention.

[0025] Figure 3 2 is a waveform diagram exemplarily illustrating an operation of detecting a situation in which a normal accessory is attached to a serial bus connector according to an embodiment of the present invention.

[0026] Figure 4 A moisture detection method according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0027] Below, some embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, although the same components are shown in different figures, the same components will be designated by the same reference numerals. In addition, when describing the present invention, when it is judged that the detailed description of the relevant known structure or function will unnecessarily confuse the gist of the present invention, its detailed description will be omitted.

[0028] In addition, in the description of the components of the present invention, words like first, second, A, B, (a) and (b) are used. These are only for distinguishing one component from another component, and do not imply or suggest the nature, order or sequence of the components. If a component is recorded as being "connected", "coupled" or "linked" to another component, they can mean that the component is not only directly "connected", "coupled" or "linked" to another component, but also indirectly "connected", "coupled" or "linked" to another component through a third component.

[0029] Figure 1 A block diagram of a moisture detection circuit according to an embodiment of the present invention is shown.

[0030] Reference Figure 1 The moisture detection circuit 100 may be connected to a wiring connected to a connector (not shown) for serial communication with a main controller (not shown) to detect whether the connector is attached with moisture or a normal accessory. The connector for serial communication may be, for example, a connector for a Universal Serial Bus Type-C (USB-C). For example, Figure 1 As shown, the moisture detection circuit 100 can be connected to the configuration channel (CC) terminal CCx of the main controller and the wiring connected to the corresponding USB-C connector CC terminal CCx_con to perform operation. Figure 1 As shown, the operation of the moisture detection circuit 100 is explained by taking the case where the moisture detection circuit 100 is connected to the CC terminal wiring of the USB-C connector as an example, but the moisture detection circuit 100 of the present invention does not necessarily have to be connected to the CC terminal wiring of the USB-C connector.

[0031] The moisture detection circuit 100 can selectively include Figure 1 At least a portion of the components shown, for example, the current digital-to-analog converter 110, the voltage digital-to-analog converter 120, the comparator 130, the controller 140, the switch driver 150 and the edge detector 160. Obviously, in addition to Figure 1 In addition to the components shown, the moisture detection circuit 100 may further include other components as required.

[0032] The current digital-to-analog converter 110 may output a reference current Iref to the connector CC terminal CCx_con. Specifically, the current digital-to-analog converter 110 may receive a first digital signal DS1 indicating a current reference value from the controller 140, and output a reference current Iref to the connector CC terminal CCx_con, wherein the reference current Iref is a current in analog form corresponding to the first digital signal DS1.

[0033] The voltage DAC 120 may output a reference voltage Vref to the comparator 130. Specifically, the voltage DAC 120 may receive a second digital signal DS2 indicating a voltage reference value from the controller 140, and output a reference voltage Vref in an analog form corresponding to the second digital signal DS2.

[0034] The comparator 130 can compare the voltage Vccx_con of the connector CC terminal CCx_con with the voltage Vref output by the voltage digital-to-analog converter 120, and provide the result signal Co to the controller 140. The voltage Vccx_con is formed at the connector CC terminal by the current Iref output by the current digital-to-analog converter 110, and the magnitude of the voltage Vccx_con can be different depending on whether the connector CC terminal CCx_con is attached with moisture or a normal accessory. The voltage digital-to-analog converter 120 can output a reference voltage Vref, which can correspond to the current Iref output by the current digital-to-analog converter 110 to distinguish between the case where moisture is attached and the case where a normal accessory is attached, and the comparator 130 can judge the type of the external object attached to the connector CC terminal CCx_con by comparing the reference voltage Vref output by the voltage digital-to-analog converter 120 with the voltage Vccx_con actually formed at the connector CC terminal.

[0035] At this time, using a reference current Iref and a reference voltage Vref, the judgment of whether there is moisture attached or a normal accessory may not be accurate. Figure 2 and Figure 3To explain, while applying a plurality of reference currents Iref, a plurality of reference voltages Vref and the voltage Vccx_con of the connector CC terminal are compared, so that it can be more accurately determined whether moisture is attached or whether the accessory is normal.

[0036] The controller 140 may provide the first digital signal DS1 indicating the current reference value to the current digital-to-analog converter 110, provide the second digital signal DS2 indicating the voltage reference value to the voltage digital-to-analog converter 120, and determine whether the connector CC terminal CCx_con is attached with moisture or a normal accessory based on the comparison result of the comparator 130. For a specific method of determining whether the connector CC terminal CCx_con is attached with moisture or a normal accessory, refer to Figure 2 and Figure 3 Provide detailed explanation.

[0037] If it is determined that the connector CC terminal CCx_con is attached with moisture, the controller 140 may cut off the connection between the main controller and the connector. To this end, the terminal connection switch CC Switch may be provided between the main controller CC terminal CCx and the connector CC terminal CCx_con, and the controller 140 may drive the terminal connection switch CC Switch by providing a switch control signal SW_ctrl to the switch driver 150. If it is determined that the connector CC terminal CCx_con is attached with moisture, the controller 140 may disconnect the terminal connection switch CC Switch through the switch driver 150 to cut off the connection between the main controller CC terminal CCx and the connector CC terminal CCx_con.

[0038] In addition, if it is determined that moisture is attached to the connector CC terminal CCx_con, the controller 140 may provide a signal Moisture_det indicating that moisture is attached to the connector CC terminal CCx_con to the outside (eg, a main controller).

[0039] The edge detector 160 can detect the rising edge or falling edge of the signal provided by the main controller to the CC terminal CCx to generate an enable signal Enable, and provide the enable signal Enable to the controller 140. The controller 140 can start the moisture detection action based on the enable signal Enable output by the edge detector 160. In other words, the controller 140 can synchronize with the enable signal Enable output by the edge detector 160 to enable the current digital-to-analog converter 110 to output the reference current Iref and the voltage digital-to-analog converter 120 to output the reference voltage Vref.

[0040] Figure 2 1 is a waveform diagram exemplarily illustrating an operation of detecting moisture adhering to a serial bus connector according to an embodiment of the present invention.

[0041] Reference Figure 2 For example, at time t1, the voltage of the main controller CC terminal CCx can change from "low" to "high". The edge detector 160 can detect the rising edge of the voltage of the main controller CC terminal CCx and change the enable signal Enable from "low" to "high". The controller 140 can start the moisture detection action based on the enable signal Enable output by the edge detector 160. That is, the controller 140 can synchronize the time when the enable signal Enable output by the edge detector 160 changes from "low" to "high", so that the current digital-to-analog converter 110 outputs the reference current Iref and the voltage digital-to-analog converter 120 outputs the reference voltage Vref.

[0042] If the moisture detection action is started, the current digital-to-analog converter 110 can output a current of the first current reference value Iref1 in the first period P1 and the second period P2, and output a current of the second current reference value Iref2 in the third period P3 and the fourth period P4. As described above, the current reference value provided by the current digital-to-analog converter 110 for each period can be set based on the first digital signal DS1 provided by the controller 140. At this time, the first period P1 is the period between t1 and t2, the second period P2 is the period between t2 and t3, the third period P3 is the period between t3 and t4, and the fourth period P4 is the period between t4 and t5.

[0043] The voltage DAC 120 may output a voltage of a first voltage reference value Vref1 in the first period P1 and the third period P3, and output a voltage of a second voltage reference value Vref2 in the second period P2 and the fourth period P4. As described above, the voltage reference value provided by the voltage DAC 120 may be set based on the second digital signal DS2 provided by the controller 140.

[0044] The comparator 130 may compare the voltage Vccx_con of the connector CC terminal CCx_con with the voltage Vref output by the voltage digital-to-analog converter 120 in each of the first to fourth periods P1 to P4 and provide a result signal Co thereof to the controller 140 .

[0045] The controller 140 may determine whether moisture or a normal component is attached to the connector CC terminal CCx_con based on the comparison result Co of the comparator 130 in the first to fourth periods P1 to P4.

[0046] As an embodiment of the present invention, Figure 2As shown, the first current reference value Iref1 may be less than the second current reference value Iref2, and the first voltage reference value Vref1 may be greater than the second voltage reference value Vref2. In this case, when the following conditions are met, the controller 140 may determine that moisture is attached to the terminal CCx_con: the terminal voltage Vccx_con in the first period P1 is less than the first voltage reference value Vref1, the terminal voltage Vccx_con in the second period P2 is greater than the second voltage reference value Vref2, the terminal voltage Vccx_con in the third period P3 is greater than the first voltage reference value Vref1, and the terminal voltage Vccx_con in the fourth period P4 is greater than the second voltage reference value Vref2. That is, if the comparison result Co of the comparator 130 sequentially outputs the value of

[0111] in the first period P1 to the fourth period P4, the controller 140 may determine that moisture is attached to the terminal CCx_con. If it is determined that moisture is attached to the terminal CCx_con, the controller 140 may change the moisture determination signal Moisture_det from "low" to "high" and output it.

[0047] At this time, the time sequence of the first period P1 to the fourth period P4 can be set arbitrarily. Figure 2 In the figure, it is shown that the sequence is the first period P1, the second period P2, the third period P3, and the fourth period P4, but, for example, it can be performed in the order of the first period P1, the third period P3, the second period P2, and the fourth period P4. In the third period P3 and the fourth period P4, the two voltage reference values ​​Vref1 and Vref20 are compared for the second current reference value Iref2, and the four situations are compared in the four periods P1 to P4. As long as the comparison of these four situations can be performed, the order can also be changed. If the time sequence of the four periods changes, the code of the comparator output signal Co judged to be attached with moisture will also change accordingly. For example, when the sequence is the second period P2, the first period P1, the third period P3, and the fourth period P4, the code of the comparator output signal Co judged to be attached with moisture can be

[1011] .

[0048] According to an embodiment, the current digital-to-analog converter 110 may be a 1-bit digital-to-analog converter that can selectively output a current of a first current reference value Iref1 and a current of a second current reference value Iref2. The voltage digital-to-analog converter 120 may be a 1-bit digital-to-analog converter that can selectively output a voltage of a first voltage reference value Vref1 and a voltage of a second voltage reference value Vref2. In this case, Figure 2As shown, four cases can be compared, and whether moisture is attached can be determined based on the results. If the resolution of the current DAC 110 and the voltage DAC 120 is increased, more sufficient comparisons of the reference current and reference voltage should be performed to obtain more accurate determination results.

[0049] exist Figure 2 In the figure, “low” and “high” of each signal are only used to illustrate an example. Obviously, “low” and “high” can be implemented in opposite or different ways while operating on the same principle.

[0050] Figure 3 2 is a waveform diagram exemplarily illustrating an operation of detecting a situation in which a normal accessory is attached to a serial bus connector according to an embodiment of the present invention.

[0051] Reference Figure 3 The generation of the enable signal Enable of the edge detector 160, the generation of the reference current Iref of the current digital-to-analog converter 110, and the generation of the reference voltage Vref of the voltage digital-to-analog converter 120 can refer to Figure 2 The same method is applicable. Figure 3 and Figure 2 The difference is that a method for judging whether a normal accessory is added to the connector CC terminal CCx_con is shown.

[0052] As an embodiment of the present invention, the current digital-to-analog converter 110 may output a current of a first current reference value Iref1 in the first period P1 and the second period P2, and output a current of a second current reference value Iref2 in the third period P3 and the fourth period P4. The voltage digital-to-analog converter 120 may output a voltage of a first voltage reference value Vref1 in the first period P1 and the third period P3, and output a voltage of a second voltage reference value Vref2 in the second period P2 and the fourth period P4.

[0053] At this time, the first current reference value Iref1 may be less than the second current reference value Iref2, and the first voltage reference value Vref1 may be greater than the second voltage reference value Vref2. In this case, the controller 140 may determine that a normal accessory is installed at the terminal CCx_con when the following conditions are met: the terminal voltage Vccx_con in the first period P1 is less than the first voltage reference value Vref1, the terminal voltage Vccx_con in the second period P2 is less than the second voltage reference value Vref2, the terminal voltage Vccx_con in the third period P3 is less than the first voltage reference value Vref1, and the terminal voltage Vccx_con in the fourth period P4 is greater than the second voltage reference value Vref2.

[0054] The order may be changed, in which case the code of the comparison result Co of the comparator 130 that determines that a normal accessory has been added will also be changed.

[0055] Figure 4 A moisture detection method according to an embodiment of the present invention is shown.

[0056] For example, Figure 4 The moisture detection method shown can be referred to Figure 1 A description is given of a moisture detection circuit for a serial bus connector.

[0057] First, the CCx signal provided by the main controller to the terminal of the serial bus connector can be detected (S410), and it can be determined whether a rising edge or a falling edge occurs in the CCx signal (S420). If a rising edge or a falling edge occurs in the CCx signal, it can enter step S430 and start voltage comparison for determining foreign matter attachment. If a rising edge or a falling edge does not occur in the CCx signal, it can return to step S410 and repeat the edge detection of the CCx signal.

[0058] Next, you can refer to Figure 2 The voltage comparison (S430) is performed in the four time periods P1 to P4 exemplarily described. For example, the following steps can be performed in sequence: a first interval comparison step, in which the terminal voltage is compared with the first voltage reference value when the current of the first current reference value is connected to the terminal of the connector; a second interval comparison step, in which the terminal voltage is compared with the second voltage reference value when the current of the first current reference value is connected to the terminal; a third interval comparison step, in which the terminal voltage is compared with the first voltage reference value when the current of the second current reference value is connected to the terminal; and a fourth interval comparison step, in which the terminal voltage is compared with the second voltage reference value when the current of the second current reference value is connected to the terminal.

[0059] Next, whether the terminal has moisture attached to it or is a normal component may be determined based on the comparison results of the first to fourth period comparison steps ( S440 ).

[0060] For example, the first current reference value may be less than the second current reference value, and the first voltage reference value may be greater than the second voltage reference value. In this case, it can be determined that moisture is attached to the terminal when the following conditions are met: the terminal voltage in the first interval comparison step is less than the first voltage reference value, the terminal voltage in the second interval comparison step is greater than the second voltage reference value, the terminal voltage in the third interval comparison step is greater than the first voltage reference value, and the terminal voltage in the fourth interval comparison step is greater than the second voltage reference value.

[0061] For example, the first current reference value may be less than the second current reference value, and the first voltage reference value may be greater than the second voltage reference value. In this case, when the following conditions are met, it can be determined that the terminal is equipped with a normal accessory: the terminal voltage in the first interval comparison step is less than the first voltage reference value, the terminal voltage in the second interval comparison step is less than the second voltage reference value, the terminal voltage in the third interval comparison step is less than the first voltage reference value, and the terminal voltage in the fourth interval comparison step is greater than the second voltage reference value.

[0062] At this point, it is easy to understand that the order of the first to fourth time period comparison steps can be changed based on the same principle as above.

[0063] If it is determined in step S440 that moisture is attached to the terminal, the switch connecting the terminal of the main controller and the terminal of the serial bus connector may be turned off ( S450 ).

[0064] In some of the above embodiments, at least a portion of the current DAC 110, the voltage DAC 120, the comparator 130, the controller 140, the switch driver 150, and the edge detector 150 may be implemented together on one semiconductor chip. In this case, regardless of the spatial separation, each structure may be distinguished by its function.

[0065] In this embodiment, if Figure 2 and Figure 3 In the embodiment shown, only two 1-bit digital-to-analog converters and one comparator are used to compare the voltages of four situations divided into four time periods. If comparators are mainly used without digital-to-analog converters, a large number of comparators and complex circuits are required. The advantage of this embodiment is that only two low-resolution (only 1-bit) digital-to-analog converters and one comparator are used to implement this function. A digital-to-analog converter with a 1-bit resolution can be implemented with a very small area on a semiconductor chip, so compared with using multiple comparators, it not only has the advantages of occupying a small semiconductor chip area and low cost, but also has the advantage of low power consumption. By increasing the resolution of the digital-to-analog converter, the advantages of the present invention can be more clear. For example, when the current digital-to-analog converter and the voltage digital-to-analog converter are respectively implemented with a 2-bit resolution, comparison can be performed in 16 time periods composed of a combination of four reference current values ​​and four reference voltage values, thereby improving the accuracy of judgment of various external objects. If comparators are mainly used without digital-to-analog converters, the structure will become very complicated.

[0066] Terms such as "including", "comprising" or "having" described above mean that, unless otherwise specified, corresponding components may exist, and therefore should be interpreted as further including other components rather than excluding other components. Unless otherwise specified, all terms (including technical or scientific terms) may be interpreted as having the same meaning as those generally understood by ordinary technicians in the field to which the embodiments of the present invention belong. General terms such as terms defined in dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant field, and will not be interpreted in an idealized or excessive form of meaning unless so clearly defined in the present invention.

[0067] The above description is merely an illustration of the technical concept of the present invention, and a person skilled in the art to which the present invention belongs will be able to make various modifications and changes without departing from the essential features of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical concept of the present invention but to illustrate it, and the scope of the technical concept of the present invention is not limited by these embodiments. The protection scope of the present invention shall be interpreted by the attached claims, and shall be interpreted as all technical concepts within the equivalent scope thereof are included in the scope of the rights of the present invention.

[0068] Description of Reference Numerals 110: Current Digital-to-Analog Converter 120: Voltage digital-to-analog converter 130: Comparator 140: Controller 150: Switch driver 160: Edge detector Iref: reference current Iref1: first current reference value Iref2: Second current reference value Vref: reference voltage Vref1: first voltage reference value Vref2: Second voltage reference value DS1: First Digital Signal DS2: Second digital signal Co: comparator output signal SW_ctrl: switch control signal Enable: Enable signal

Claims

1. A moisture detection circuit for a serial bus connector, the moisture detection circuit detecting moisture attached to a terminal of the serial bus connector, comprising: a current digital-to-analog converter that receives a first digital signal indicating a current reference value and outputs a current in an analog form having a magnitude corresponding to the first digital signal to a terminal of the serial bus connector; a voltage digital-to-analog converter, the voltage digital-to-analog converter receiving a second digital signal indicating a voltage reference value and outputting a voltage in analog form having a magnitude corresponding to the second digital signal; a comparator that compares the voltage of the terminal with the analog voltage output by the voltage digital-to-analog converter; and A controller is provided to provide a first digital signal indicating the current reference value to the current digital-to-analog converter, a second digital signal indicating the voltage reference value to the voltage digital-to-analog converter, and determines whether moisture is attached to the terminal based on a comparison result of the comparator.

2. The moisture detection circuit for a serial bus connector according to claim 1, characterized in that: The current digital-to-analog converter outputs a current of a first current reference value in a first period P1 and a second period P2, and outputs a current of a second current reference value in a third period P3 and a fourth period P4, The voltage digital-to-analog converter outputs a voltage of a first voltage reference value in the first period P1 and the third period P3, and outputs a voltage of a second voltage reference value in the second period P2 and the fourth period P4, The comparator compares the voltage of the terminal with the analog voltage output by the voltage digital-to-analog converter in each of the first to fourth periods P1 to P4, The controller determines whether moisture is attached to the terminal based on the comparison result of the comparator in the first period P1 to the fourth period P4, The time sequence of the first period P1 to the fourth period P4 can be set arbitrarily.

3. The moisture detection circuit for a serial bus connector according to claim 2, characterized in that: When the following conditions are met, the controller determines that moisture is attached to the terminal: The first current reference value is smaller than the second current reference value, The first voltage reference value is greater than the second voltage reference value, The terminal voltage in the first period P1 is less than the first voltage reference value, The terminal voltage in the second period P2 is greater than the second voltage reference value, The terminal voltage in the third period P3 is greater than the first voltage reference value, and The terminal voltage in the fourth period P4 is greater than the second voltage reference value.

4. The moisture detection circuit for a serial bus connector according to claim 2, characterized in that: When the following conditions are met, the controller determines that a normal accessory is installed on the terminal: The first current reference value is smaller than the second current reference value, The first voltage reference value is greater than the second voltage reference value, The terminal voltage in the first period P1 is less than the first voltage reference value, The terminal voltage in the second period P2 is less than the second voltage reference value, The terminal voltage in the third period P3 is less than the first voltage reference value, and The terminal voltage in the fourth period P4 is greater than the second voltage reference value.

5. The moisture detection circuit for a serial bus connector according to claim 1, characterized in that: The current digital-to-analog converter is a 1-bit digital-to-analog converter that can selectively output a current of a first current reference value and a current of a second current reference value. The voltage digital-to-analog converter is a 1-bit digital-to-analog converter that can selectively output a voltage of a first voltage reference value and a voltage of a second voltage reference value.

6. The moisture detection circuit for a serial bus connector according to claim 1, characterized in that: An edge detector is also included, the edge detector detects a rising edge or a falling edge of a signal provided by the main controller to the terminal to generate an enable signal, and provides the enable signal to the controller.

7. The moisture detection circuit for a serial bus connector according to claim 6, characterized in that: The controller starts a moisture detection operation based on the enable signal output by the edge detector.

8. The moisture detection circuit for a serial bus connector according to claim 1, characterized in that: If it is determined that moisture is attached to the terminal, the controller disconnects the terminal connection switch connecting the main controller and the terminal.

9. A moisture detection method for a serial bus connector, the moisture detection method being performed by means of a moisture detection circuit for the serial bus connector, comprising: A first time period comparison step, in which a current of a first current reference value is connected to a terminal of the connector, comparing a terminal voltage at the terminal with a first voltage reference value; A second time period comparison step, in which the terminal voltage is compared with a second voltage reference value when the current of the first current reference value is connected to the terminal; A third time period comparison step, in a state where a current of a second current reference value is connected to the terminal, comparing the terminal voltage with the first voltage reference value; a fourth time period comparison step, comparing the terminal voltage with the second voltage reference value when the current of the second current reference value is connected to the terminal; and A step of determining whether moisture is attached to the terminal based on the comparison results of the first period comparison step to the fourth period comparison step.

10. The moisture detection method for a serial bus connector according to claim 9, characterized in that: When the following conditions are met, it is determined that moisture is attached to the terminal: The first current reference value is smaller than the second current reference value, The first voltage reference value is greater than the second voltage reference value, The terminal voltage in the first period comparison step is less than the first voltage reference value, The terminal voltage in the second period comparison step is greater than the second voltage reference value, The terminal voltage in the third period comparison step is greater than the first voltage reference value, and The terminal voltage in the fourth period comparison step is greater than the second voltage reference value.

11. The moisture detection method for a serial bus connector according to claim 9, characterized in that: When the following conditions are met, it is determined that the terminal is equipped with normal accessories: The first current reference value is smaller than the second current reference value, The first voltage reference value is greater than the second voltage reference value, The terminal voltage in the first period comparison step is less than the first voltage reference value, The terminal voltage in the second period comparison step is less than the second voltage reference value, The terminal voltage in the third period comparison step is less than the first voltage reference value, and When the terminal voltage in the fourth time period comparison step is greater than the second voltage reference value.

12. The moisture detection method for a serial bus connector according to claim 9, characterized in that: The moisture detection method starts based on a rising edge or a falling edge of a signal provided by a main controller to a terminal of the serial bus connector.

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