Type-C interface foreign matter detection device and detection method thereof

Abstract

The invention discloses a Type-C interface foreign matter detection device and a detection method thereof.The Type-C interface foreign matter detection device comprises a multiplexer switch MUX, an excitation signal source, a signal processing module, an ADC and a digital processing module, the multiplexer switch MUX selects one of multiple detection ports of a Type-C interface for foreign matter detection, the excitation signal source outputs a plurality of excitation signals, and the signal processing module outputs the excitation signals; the signal processing module samples the excitation signal and converts the excitation signal into a digital signal through an ADC to be calculated and processed by the digital processing module, and the digital processing module calculates the impedance of the detection port. Whether the foreign matter occurs at the port or not is judged by detecting the impedance of the foreign matter at the port.

Description

Technical Field

[0001] The technical problem to be solved by the present invention is to provide a foreign body detection device and a detection method thereof, in particular, a Type-C interface foreign body detection device and a detection method thereof, which belongs to the field of semiconductor integrated circuit technology. Background Art

[0002] Type-C interface is widely used in modern electronic devices due to its advantages such as supporting high-speed interface, fast charging and reversible insertion. The Type-C interface of most electronic devices is exposed when not connected, and it is easy to be introduced by foreign objects, such as tap water, sea water, juice, sweat and other liquids. These liquids will also adhere to various fines and corrode the pins between the interfaces, and the presence of electricity will accelerate the corrosion. Therefore, how to reliably detect foreign objects in the Type-C interface is a technical problem that technicians in this field need to solve urgently.

[0003] In the prior art, when the Type-C interface itself is performing CC detection, the resistors Rp, Ra, and Rd connected to CC1 (or CC2) have different values, and the current source has different values, such as 80uA, 180uA, and 330uA, to calculate the theoretical port voltage value. When a foreign object enters the Type-C interface, the port voltage will be tested to a voltage that deviates from the theoretical value, thereby determining that a foreign object has entered. Some existing foreign object detection solutions have the problem of a single judgment condition, and only detect the resistance value, which is prone to misjudgment and has low foreign object detection accuracy. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a Type-C interface foreign body detection device and a detection method thereof to improve the accuracy of foreign body detection.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is: A Type-C interface foreign body detection device comprises a multi-way selection switch MUX, an excitation signal source, a signal processing module, an ADC and a digital processing module. The input end of the multi-way selection switch MUX is respectively connected to multiple detection ports of the Type-C interface, the output end of the multi-way selection switch MUX is connected to the output end of the excitation signal source and the input end of the signal processing module, the output end of the signal processing module is connected to the input end of the ADC, the output end of the ADC is connected to the input end of the digital processing module, the multi-way selection switch MUX selects one of the multiple detection ports of the Type-C interface for foreign body detection, the excitation signal source outputs a plurality of excitation signals, the signal processing module samples the excitation signals and converts them into digital signals through the ADC for calculation and processing by the digital processing module, and the digital processing module calculates the impedance of the detection port.

[0006] Furthermore, the multiple detection ports of the Type-C interface include port DP, port DN, port SBU1, port SBU2, port CC1 and port CC2.

[0007] Furthermore, the excitation signal output by the excitation signal source includes a direct current excitation signal and an alternating current excitation signal.

[0008] Furthermore, the DC excitation signal includes a voltage source, a current source and a current sink.

[0009] Furthermore, the AC excitation signal includes a sine wave, a square wave and a triangle wave.

[0010] A detection method for a Type-C interface foreign body detection device comprises the following steps: S1. For a new Type-C interface, the multi-way selection switch MUX selects a detection port of the Type-C interface; S2, the excitation source generates several excitation signals in sequence, each excitation signal is sampled by the signal processing module and converted into a digital signal by the ADC, and finally the impedance of the port to be detected is calculated by the digital processing module; S3, the multi-way selection switch MUX selects the next detection port of the Type-C interface and repeats step S2 until all the detection ports of the Type-C interface are detected, and the parasitic resistance and parasitic capacitance of all the detection ports of the new Type-C interface are obtained; S4, when detecting foreign matter on the Type-C interface, the multi-way selection switch MUX selects a detection port of the Type-C interface; S5, the excitation source generates several excitation signals in sequence, each excitation signal is sampled by the signal processing module and converted into a digital signal by the ADC, and finally the impedance of the port to be detected is calculated by the digital processing module; S6. The multi-way selection switch MUX selects the next detection port of the Type-C interface and repeats step S5 until all the detection ports of the Type-C interface have completed the detection, and the current resistance and current capacitance of all the detection ports of the Type-C interface are obtained; S7, calculate the resistance difference between the current resistance and the parasitic resistance, calculate the capacitance difference between the current capacitance and the parasitic capacitance, and determine whether the resistance difference is greater than the resistance threshold. If so, there is a foreign object. If the capacitance difference is greater than the capacitance threshold, there is a foreign object.

[0011] Furthermore, the calculation process of the impedance of the port to be detected in steps S2 and S5 is: A current source or current sink is used to excite the port to be detected. The sampled excitation signal is processed by the signal processing module and quantized by the ADC to obtain the equation: ; Where R is the resistance matrix, I is the current matrix, and V is the voltage matrix, and they conform to: ; ; ; Among them, R11, R12, R21, R22 are the values ​​of the resistance matrix R, I11, I12 are the values ​​of the current matrix I, V11, V12 are the values ​​of the voltage matrix; Assume that the current of the current source of the excitation added to the port to be detected is I1, the current of the current sink is I2, the voltage of the port to be detected corresponding to the current I1 is V1, and the voltage of the port to be detected corresponding to the current I2 is V2, then: ; ; ; because , can be obtained ; Solving the above equation, we can get the values ​​of resistors R1 and R2; A sine wave is used to excite the port to be detected. The sampled excitation signal is processed by the signal processing module and quantized by the ADC. For different resistors R and capacitors C, there are different phase relationships between the current I of the port to be detected and the voltage V of the port to be detected: ; We can get: ; in, is the phase of the current I at the port to be detected, is the phase of the voltage V at the port to be detected, is the phase difference between current I and voltage V; R is the parallel value of resistor R1 and resistor R2, j is the imaginary number sign, is the frequency; According to the tested phase relationship between the current I and the voltage V of the port to be detected, the value of the equivalent capacitance C of the port to be detected is calculated; Furthermore, the calculation process of the impedance of the port to be detected in steps S2 and S5 is: A current source or current sink is used to excite the port to be detected. The sampled excitation signal is processed by the signal processing module and quantized by the ADC to obtain the equation: ; Where R is the resistance matrix, I is the current matrix, and V is the voltage matrix, and they conform to: ; ; ; Among them, R11, R12, R21, R22 are the values ​​of the resistance matrix R, I11, I12 are the values ​​of the current matrix I, and V11, V12 are the values ​​of the voltage matrix.

[0012] Assume that the current of the current source of the excitation added to the port to be detected is I1, the current of the current sink is I2, the voltage of the port to be detected corresponding to the current I1 is V1, and the voltage of the port to be detected corresponding to the current I2 is V2, then: ; ; ; because , can be obtained ; Solving the above equation, we can get the values ​​of resistors R1 and R2.

[0013] A sine wave is used to excite the port to be detected. The sampled excitation signal is processed by the signal processing module and quantized by the ADC. For different resistors R and capacitors C, there are different phase relationships between the current I of the port to be detected and the voltage V of the port to be detected: ; We can get: ; Among them, Im is the effective value of the current amplitude, and Vm is the effective value of the voltage amplitude.

[0014] According to the relationship between the tested current amplitude effective value Im and the voltage amplitude effective value Vm of the port to be detected, the value of the equivalent capacitance C of the port to be detected is calculated.

[0015] Compared with the prior art, the present invention has the following advantages and effects: The present invention provides a Type-C interface foreign body detection device and a detection method thereof, which can detect the impedance of the port foreign body to determine whether there is a foreign body in the port. At the same time, a calibration test scheme is proposed for the influence of port parasitic capacitance in actual production assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of a Type-C interface foreign body detection device of the present invention.

[0017] Figure 2 It is a detection schematic diagram of a Type-C interface foreign body detection device of the present invention.

[0018] Figure 3 It is a schematic diagram of a calibration scheme of a Type-C interface foreign body detection device of the present invention.

[0019] Figure 4 It is a flow chart of a Type-C interface foreign body detection method of the present invention.

[0020] Figure 5 It is a schematic diagram of the pin definition of the Type-C interface of the present invention. DETAILED DESCRIPTION

[0021] In order to elaborate on the technical scheme adopted by the present invention to achieve the predetermined technical purpose, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only partial embodiments of the present invention, rather than all embodiments, and the technical means or technical features in the embodiments of the present invention can be replaced without paying creative work. The present invention will be described in detail below with reference to the drawings and in conjunction with the embodiments.

[0022] like Figure 1 As shown, a Type-C interface foreign body detection device of the present invention includes a multi-way selection switch MUX, an excitation signal source, a signal processing module, an ADC and a digital processing module. The input end of the multi-way selection switch MUX is respectively connected to multiple detection ports of the Type-C interface, the output end of the multi-way selection switch MUX is connected to the output end of the excitation signal source and the input end of the signal processing module, the output end of the signal processing module is connected to the input end of the ADC, the output end of the ADC is connected to the input end of the digital processing module, the multi-way selection switch MUX selects one of the multiple detection ports of the Type-C interface for foreign body detection, the excitation signal source outputs a plurality of excitation signals, the signal processing module samples the excitation signal and converts it into a digital signal through the ADC for calculation and processing by the digital processing module, and the digital processing module calculates the impedance of the detection port.

[0023] like Figure 5 As shown, the multiple detection ports of the Type-C interface include port DP, port DN, port SBU1, port SBU2, port CC1 and port CC2.

[0024] The excitation signal output by the excitation signal source includes a DC excitation signal and an AC excitation signal. The DC excitation signal includes a voltage source, a current source, and a current sink. The AC excitation signal includes a sine wave, a square wave, and a triangle wave.

[0025] like Figure 2 As shown, the excitation signal source controls the switching-in of multiple excitation signal sources one by one through a switch.

[0026] like Figure 4 As shown, a detection method of a Type-C interface foreign body detection device comprises the following steps: S1. For a new Type-C interface (i.e., a Type-C interface without foreign objects), the multi-way selection switch MUX selects a detection port of the Type-C interface.

[0027] S2. The excitation source generates several excitation signals in sequence. Each excitation signal is sampled by the signal processing module and converted into a digital signal through the ADC. Finally, the impedance of the port to be detected is calculated by the digital processing module.

[0028] S3, the multi-way selection switch MUX selects the next detection port of the Type-C interface and repeats step S2 until all the detection ports of the Type-C interface have completed the detection, such as Figure 3 As shown, the parasitic resistances R3 and R4 and the parasitic capacitances C3 and C4 of all detection ports of the new Type-C interface are obtained.

[0029] S4. When detecting foreign objects on the Type-C interface, the multi-way selection switch MUX selects a detection port of the Type-C interface.

[0030] S5. The excitation source generates several excitation signals in sequence. Each excitation signal is sampled by the signal processing module and converted into a digital signal through the ADC. Finally, the impedance of the port to be detected is calculated by the digital processing module.

[0031] S6. The multi-way selection switch MUX selects the next detection port of the Type-C interface and repeats step S5 until all the detection ports of the Type-C interface are detected, and the current resistances R5 and R6 and the current capacitances C5 and C6 of all the detection ports of the Type-C interface are obtained.

[0032] S7, calculate the resistance difference between the current resistance and the parasitic resistance, calculate the capacitance difference between the current capacitance and the parasitic capacitance, and determine whether the resistance difference is greater than the resistance threshold. If so, there is a foreign object. If the capacitance difference is greater than the capacitance threshold, there is a foreign object.

[0033] In the present invention, steps S1-S3 can be tested before leaving the factory and used as calibration values. These calibration values ​​are subtracted during actual measurement to obtain accurate measurement values.

[0034] The calculation process of the impedance of the port to be detected in steps S2 and S5 is as follows: like Figure 2 As shown, a current source or a current sink is used to excite the port to be detected. The sampled excitation signal is processed by the signal processing module and quantized by the ADC to obtain the equation: ; Where R is the resistance matrix, I is the current matrix, and V is the voltage matrix, and they conform to: ; ; ; Among them, R11, R12, R21, R22 are the values ​​of the resistance matrix R, I11, I12 are the values ​​of the current matrix I, and V11, V12 are the values ​​of the voltage matrix.

[0035] Assume that the current of the current source of the excitation added to the port to be detected is I1, the current of the current sink is I2, the voltage of the port to be detected corresponding to the current I1 is V1, and the voltage of the port to be detected corresponding to the current I2 is V2, then: ; ; ; because , can be obtained ; Solving the above equation, we can get the values ​​of resistors R1 and R2.

[0036] A sine wave is used to excite the port to be detected. The sampled excitation signal is processed by the signal processing module and quantized by the ADC. For different resistors R and capacitors C, there are different phase relationships between the current I of the port to be detected and the voltage V of the port to be detected: ; ; in, is the phase of the current I at the port to be detected, is the phase of the voltage V at the port to be detected, is the phase difference between current I and voltage V, which can be directly measured at the port; R is the parallel value of resistor R1 and resistor R2, j is the imaginary number sign, It's the frequency.

[0037] According to the tested phase relationship between the current I and the voltage V of the port to be detected, the value of the equivalent capacitance C of the port to be detected is calculated.

[0038] In another embodiment, the calculation process of the impedance of the port to be detected in steps S2 and S5 is: like Figure 2 As shown, a current source or a current sink is used to excite the port to be detected. The sampled excitation signal is processed by the signal processing module and quantized by the ADC to obtain the equation: ; Where R is the resistance matrix, I is the current matrix, and V is the voltage matrix, and they conform to: ; ; ; Among them, R11, R12, R21, R22 are the values ​​of the resistance matrix R, I11, I12 are the values ​​of the current matrix I, and V11, V12 are the values ​​of the voltage matrix.

[0039] Assume that the current of the current source of the excitation added to the port to be detected is I1, the current of the current sink is I2, the voltage of the port to be detected corresponding to the current I1 is V1, and the voltage of the port to be detected corresponding to the current I2 is V2, then: ; ; ; because , can be obtained ; Solving the above equation, we can get the values ​​of resistors R1 and R2.

[0040] A sine wave is used to excite the port to be detected. The sampled excitation signal is processed by the signal processing module and quantized by the ADC. For different resistors R and capacitors C, there are different phase relationships between the current I of the port to be detected and the voltage V of the port to be detected: ; We can get: ; Among them, Im is the effective value of the current amplitude, and Vm is the effective value of the voltage amplitude.

[0041] According to the relationship between the tested current amplitude effective value Im and the voltage amplitude effective value Vm of the port to be detected, the value of the equivalent capacitance C of the port to be detected is calculated.

[0042] The present invention provides a Type-C interface foreign body detection device and a detection method thereof, which can detect the impedance of the port foreign body to determine whether there is a foreign body in the port. At the same time, a calibration test scheme is proposed for the influence of port parasitic capacitance in actual production assembly.

[0043] The above is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with this profession can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent replacement and improvement made to the above embodiments without departing from the content of the technical solution of the present invention, based on the technical essence of the present invention, within the spirit and principles of the present invention, still fall within the protection scope of the technical solution of the present invention.

Claims

1. A Type-C interface foreign body detection device, characterized in that: It includes a multi-way selection switch MUX, an excitation signal source, a signal processing module, an ADC and a digital processing module. The input end of the multi-way selection switch MUX is respectively connected to multiple detection ports of the Type-C interface, the output end of the multi-way selection switch MUX is connected to the output end of the excitation signal source and the input end of the signal processing module, the output end of the signal processing module is connected to the input end of the ADC, the output end of the ADC is connected to the input end of the digital processing module, the multi-way selection switch MUX selects one of the multiple detection ports of the Type-C interface for foreign body detection, the excitation signal source outputs several excitation signals, the signal processing module samples the excitation signal and converts it into a digital signal through the ADC for calculation and processing by the digital processing module, and the digital processing module calculates the impedance of the detection port.

2. A Type-C interface foreign body detection device according to claim 1, characterized in that: The multiple detection ports of the Type-C interface include port DP, port DN, port SBU1, port SBU2, port CC1 and port CC2.

3. A Type-C interface foreign body detection device according to claim 1, characterized in that: The excitation signal output by the excitation signal source includes a direct current excitation signal and an alternating current excitation signal.

4. A Type-C interface foreign body detection device according to claim 3, characterized in that: The DC excitation signal includes a voltage source, a current source and a current sink.

5. A Type-C interface foreign body detection device according to claim 3, characterized in that: The AC excitation signal includes a sine wave, a square wave and a triangle wave.

6. A detection method for a Type-C interface foreign body detection device according to any one of claims 1 to 5, characterized in that The following steps are involved: S1. For a new Type-C interface, the multi-way selection switch MUX selects a detection port of the Type-C interface; S2, the excitation source generates several excitation signals in sequence, each excitation signal is sampled by the signal processing module and converted into a digital signal by the ADC, and finally the impedance of the port to be detected is calculated by the digital processing module; S3, the multi-way selection switch MUX selects the next detection port of the Type-C interface and repeats step S2 until all the detection ports of the Type-C interface are detected, and the parasitic resistance and parasitic capacitance of all the detection ports of the new Type-C interface are obtained; S4, when detecting foreign matter on the Type-C interface, the multi-way selection switch MUX selects a detection port of the Type-C interface; S5, the excitation source generates several excitation signals in sequence, each excitation signal is sampled by the signal processing module and converted into a digital signal by the ADC, and finally the impedance of the port to be detected is calculated by the digital processing module; S6. The multi-way selection switch MUX selects the next detection port of the Type-C interface and repeats step S5 until all the detection ports of the Type-C interface have completed the detection, and the current resistance and current capacitance of all the detection ports of the Type-C interface are obtained; S7, calculate the resistance difference between the current resistance and the parasitic resistance, calculate the capacitance difference between the current capacitance and the parasitic capacitance, and determine whether the resistance difference is greater than the resistance threshold. If so, there is a foreign object. If the capacitance difference is greater than the capacitance threshold, there is a foreign object.

7. The detection method according to claim 6, characterized in that: The calculation process of the impedance of the port to be detected in steps S2 and S5 is: A current source or current sink is used to excite the port to be detected. The sampled excitation signal is processed by the signal processing module and quantized by the ADC to obtain the equation: ； Where R is the resistance matrix, I is the current matrix, and V is the voltage matrix, and they conform to: ； ； ； Among them, R11, R12, R21, R22 are the values ​​of the resistance matrix R, I11, I12 are the values ​​of the current matrix I, V11, V12 are the values ​​of the voltage matrix; Assume that the current of the current source of the excitation added to the port to be detected is I1, the current of the current sink is I2, the voltage of the port to be detected corresponding to the current I1 is V1, and the voltage of the port to be detected corresponding to the current I2 is V2, then: ； ； ； because , can be obtained ； Solving the above equation, we can get the values ​​of resistors R1 and R2; A sine wave is used to excite the port to be detected. The sampled excitation signal is processed by the signal processing module and quantized by the ADC. For different resistors R and capacitors C, there are different phase relationships between the current I of the port to be detected and the voltage V of the port to be detected: ； We can get: ； in, is the phase of the current I at the port to be detected, is the phase of the voltage V at the port to be detected, is the phase difference between current I and voltage V; R is the parallel value of resistor R1 and resistor R2, j is the imaginary number sign, is the frequency; According to the tested phase relationship between the current I and the voltage V of the port to be detected, the value of the equivalent capacitance C of the port to be detected is calculated.

8. The detection method according to claim 6, characterized in that: The calculation process of the impedance of the port to be detected in steps S2 and S5 is: A current source or current sink is used to excite the port to be detected. The sampled excitation signal is processed by the signal processing module and quantized by the ADC to obtain the equation: ； Where R is the resistance matrix, I is the current matrix, and V is the voltage matrix, and they conform to: ； ； ； Among them, R11, R12, R21, R22 are the values ​​of the resistance matrix R, I11, I12 are the values ​​of the current matrix I, V11, V12 are the values ​​of the voltage matrix; Assume that the current of the current source of the excitation added to the port to be detected is I1, the current of the current sink is I2, the voltage of the port to be detected corresponding to the current I1 is V1, and the voltage of the port to be detected corresponding to the current I2 is V2, then: ； ； ； because , can be obtained ； Solving the above equation, we can get the values ​​of resistors R1 and R2; A sine wave is used to excite the port to be detected. The sampled excitation signal is processed by the signal processing module and quantized by the ADC. For different resistors R and capacitors C, there are different phase relationships between the current I of the port to be detected and the voltage V of the port to be detected: ； We can get: ； Among them, Im is the effective value of the current amplitude, Vm is the effective value of the voltage amplitude; According to the relationship between the tested current amplitude effective value Im and the voltage amplitude effective value Vm of the port to be detected, the value of the equivalent capacitance C of the port to be detected is calculated.

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