WO2020000371A1

WO2020000371A1 - Usb seat operating circuit and terminal

Info

Publication number: WO2020000371A1
Application number: PCT/CN2018/093680
Authority: WO
Inventors: 马波; 王朝; 罗伟
Original assignee: 华为技术有限公司
Priority date: 2018-06-29
Filing date: 2018-06-29
Publication date: 2020-01-02
Also published as: CN112313928A; CN112313928B

Abstract

A USB seat operating circuit and a terminal, which relate to the technical field of circuits and which may meet RE testing requirements while ensuring wireless performance. The USB seat operating circuit comprises a USB seat (101), a switch circuit (102), a controller (103), and a capacitor array (104); the USB seat comprises one or more grounding pins (6, 7, 8, 9), and the capacitor array comprises one or more grounding capacitors (C311, C312); an end of the switch circuit is connected to a first grounding pin (6, 8) of the USB seat, while the other end is connected to the capacitor array; a controller is used to control the switch circuit to connect when data is being transmitted on the USB seat, and to control the switch circuit to disconnect when no data is transmitted on the USB seat.

Description

USB socket running circuit and terminal

Technical field

The present application relates to the field of circuit technology, and in particular, to a universal serial bus (Universal Serial Bus, USB) base operating circuit and a terminal.

Background technique

In the current design of terminals (such as mobile phones, tablets, etc.), the USB socket is usually set on the top or bottom of the motherboard inside the terminal and is close to the antenna. Users can plug the USB cable into the USB interface of the USB socket to charge the terminal and / Or data transfer. When the USB socket is directly grounded, the USB socket is a metal conductive shell and the shell is connected to the ground, so that when the antenna is in operation, the overflowed high-frequency harmonics will flow into the ground through the USB shell's metal shell, affecting the antenna performance.

In order not to affect the antenna performance, the existing USB socket is not directly soldered to the motherboard, that is, it cannot be directly grounded, but is set on the motherboard in a floating manner. For example, as shown in Figure 1, the USB socket is not directly connected to the motherboard, but is connected to the motherboard through multiple resistors, capacitors or inductors to achieve grounding. However, when the USB socket is suspended, the outer shielding layer of the cable end of the USB data cable is equivalent to the suspension, which will cause a large frequency interference during the USB signal transmission, which is not conducive to radiated interference during data transmission. , RE) test, making the RE test fail.

Therefore, how to meet the RE test requirements while ensuring antenna performance has become a technical issue that needs to be solved at present.

Summary of the invention

The application provides a USB socket operating circuit and a terminal, which can meet the RE test requirements while ensuring antenna performance.

In order to achieve the above purpose, this application uses the following technical solutions:

In a first aspect, the present application provides a USB base operating circuit. The USB base operating circuit includes a USB base, a switch circuit, a controller, and a capacitor array. The USB base includes one or more ground pins. The capacitor array includes one or more ground pins. One ground capacitor; one end of the switch circuit is connected to the first ground pin included in the USB socket, and the other end of the switch circuit is connected to the capacitor array; the controller is used to control the communication of the switch circuit when there is data transmission on the USB socket; When there is no data transmission on the USB socket, the control switch circuit is turned off. Based on the USB socket operating circuit provided in this application, when a user inserts a USB data cable into the USB interface of the USB socket and transmits data through the data pins of the USB socket, the controller 103 controls the switch circuit 102 to communicate, and the grounding lead of the USB socket Pin is grounded through a capacitor. Because the capacitor has the physical characteristics of blocking AC and DC, in this way, the frequency-multiplied signal generated in the case of USB interface data transmission can be transmitted to the ground through the grounding capacitor to achieve equivalent grounding for the cable shield and maximize attenuation of the USB. Frequency and octave signals to reduce or eliminate the impact on the RE test. When there is no data transmission on the USB interface, the controller 103 directly controls the switch circuit 102 to disconnect the connection to the ground capacitor, so that the ground capacitor is not connected to the transmission link. The shell of the USB socket is equivalent to an open circuit. The antenna is equivalent to a high-impedance state and will not affect antenna performance.

In a possible design, in combination with the first aspect, the first ground pin may be pin 6 and pin 8 of the USB socket.

In another possible design, in combination with the first aspect or the foregoing possible design, the USB base operating circuit further includes a first LC circuit, and the first LC circuit is composed of an inductor and a capacitor; one end of the first LC circuit is connected to the first base of the USB base. Two ground pins are connected, and the other end of the first LC circuit is grounded. The second ground pin may be two pins, pin7 and pin9 of the USB socket, so as to avoid the influence of the interference frequency signal generated by the USB socket 101 and the interference frequency signal generated when the antenna is running.

In another possible design, in combination with the first aspect or the foregoing possible design, the USB socket operating circuit further includes a second LC circuit, and the USB socket further includes a data pin; one end of the second LC circuit and the data pin of the USB socket Connected, the other end of the second LC circuit is grounded. In this way, the common-mode electromagnetic interference on the signal line can be filtered, and at the same time, the electromagnetic signal is prevented from being transmitted to the outside when the USB signal is transmitted, so as to avoid affecting the normal operation of other electronic devices in the same electromagnetic environment.

In a second aspect, the present application further provides a terminal, and the terminal may include the USB socket running circuit according to the first aspect or any possible design of the first aspect.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a floating design of an existing USB socket;

FIG. 2 is a schematic diagram of a USB socket operating circuit provided by an embodiment of the present application; FIG.

FIG. 3 is a schematic diagram of another USB socket running circuit according to an embodiment of the present application; FIG.

FIG. 4 is a schematic diagram of a terminal according to an embodiment of the present application.

detailed description

The embodiments of the embodiments of the present application will be described in detail below with reference to the drawings.

FIG. 2 shows a USB docking operating circuit 100. The USB docking running circuit may be provided on the motherboard of the terminal in a floating manner as shown in FIG. 1. The terminal may include, but is not limited to, a personal computer (PC), Personal digital assistants (PDAs), wireless handheld devices, tablet computers, smartphones, etc. As shown in FIG. 2, the shell circuit may include a USB socket 101, a switch circuit 102, a controller 103, and a capacitor array 104.

Among them, the USB socket 101 can charge a terminal and / or a USB data transmission interface connector, and can include a power pin, a data pin (D- and D +), an OTG (On The Go) pin, and multiple ground pins ( GND_1 ~ GND_5), these pins can be integrated on the same chip, and the chip can be fixed on the shell (not shown in Figure 2) of the USB socket. As shown in Figure 2, the power pin can be pin1, and the power pin can be used to connect the power supply for the USB socket to work. The data pins can be pin2 and pin3. The data pins are used to receive / send signals transmitted through the USB data line. The OTG pin can be pin4, which can be used to implement data transfer between devices without a host. GND_1 can be pin5, which is equivalent to the negative pole of the power supply. GND_2 to GND_5 correspond to pins 6 to pin 9 and can be used to fix the chip in the USB socket on the housing of the USB socket. Among them, the first ground pin in GND_2 to GND_5 can also be used to connect with the switching circuit 102, such as: A ground pin can be pin6 and pin8, and pin6 and pin8 are connected to the switch circuit 102. The shell of the USB socket can be a metal shell. It should be noted that FIG. 2 is only an exemplary drawing. In this application, the type of the USB socket 101 and the number of power pins and ground pins included in the USB socket 101 are not limited, and except for FIG. 2 In addition to the pins shown, the USB socket 101 may include other pins.

The switch circuit 102 is connected between the capacitor array 104 and a ground pin (such as pin 6 and pin 8) of the USB socket 101. The switch circuit 102 can be in a connected state or an off state under the control of the controller 103. Optionally, as shown in FIG. 2, the switching circuit 102 includes two contacts (contact 1 and contact 2) and a gate blade. The contact 1 is connected to the capacitor array 104, and the contact 2 is connected to the ground lead of the USB socket. The pins (pin6 and pin8) are connected, and one end of the gate blade is actively connected. Under the control of the controller 103, the gate blade in the switching circuit 102 is in contact with or away from the contact 1. When the gate blade is in contact with the contact 1 ( (Ie closed), the switch circuit 102 is communicated, and when the gate blade is away from the contact 1 (ie when opened), the switch circuit 102 is opened. It should be noted that the switch circuit 102 includes, but is not limited to, the form shown in FIG. 2, and may also be implemented in other ways. For details, refer to FIG. 3 described below.

The controller 103 may be a central processing unit (CPU), a specific integrated circuit (Application Specific Integrated Circuit, ASIC), or one or more integrated circuits configured to implement the embodiments of the present application. For example: one or more digital signal processors (DSPs), or one or more field programmable gate arrays (FPGAs). The controller 103 can be used to detect whether there is data transmission on the data pins on the USB socket 101 and to control the connection or disconnection of the switching circuit 102 according to the data transmission conditions on the data pins. For example, when the data pins on the data pins are detected, During data transmission, the control switch circuit 102 is connected; when no data transmission is detected on the data pin, the control switch circuit 102 is turned off. Specifically, the controller 103 may detect the current value on the data pin. If the detected current value is greater than a preset threshold, it is determined that there is data transmission on the data pin, otherwise, it is determined that there is no data transmission on the data pin. The preset threshold can be set as needed, without limitation.

The capacitor array 104 may be connected to the switching circuit 102. The capacitor array 104 may include one or more capacitors, and each capacitor may be grounded. In the embodiment of the present application, the grounded capacitor may be referred to as a grounded capacitor, as shown in FIG. 2, Both C311 and C312 can be called ground capacitors. It should be noted that the number of ground capacitors included in the capacitor array 104 and the capacitance value of each ground capacitor can be set as needed, without limitation. For example, the capacitance value of C311 can be set to 1n, and the capacitance value of C312 can be set to 470pF.

It can be seen from Figure 2 that the USB socket operating circuit is to add one or more ground capacitors between the ground pin of the USB socket and the ground terminal. When the user inserts the USB data cable into the USB interface of the USB socket, the data of the USB socket is passed. When the pin transmits data, the controller 103 controls the switch circuit 102 to communicate, and the ground pin of the USB socket is grounded through a capacitor. Because the capacitor has the physical characteristics of blocking AC and DC, in this way, the frequency-doubling signal generated during the USB interface data transmission can be transmitted to the ground through the grounding capacitor to achieve equivalent grounding for the cable shielding layer and maximize attenuation of the USB frequency and Frequency doubling signal to reduce or eliminate the impact on the RE test. When there is no data transmission on the USB interface, the controller 103 directly controls the switch circuit 102 to disconnect the connection to the ground capacitor, so that the ground capacitor is not connected to the transmission link. The shell of the USB socket is equivalent to an open circuit to the antenna. The equivalent high impedance state will not affect antenna performance.

Optionally, in order to avoid the influence of the interference frequency signal generated by the USB base 101 and the interference frequency signal generated when the antenna is running, as shown in FIG. 2, the USB base operating circuit 100 further includes a first LC circuit composed of an inductor and a capacitor: The LC circuit 1 is connected to the second ground pins (such as pin7 and pin9) of the USB base 101, and is used to absorb the interference frequency signals generated by the USB base 101 and the antenna.

Optionally, in order to filter out common-mode electromagnetic interference on the signal line, on the other hand, it is used to suppress the external electromagnetic interference when transmitting the USB signal, so as to avoid affecting the normal work of other electronic devices in the same electromagnetic environment. As shown in FIG. 2, the USB socket operating circuit 100 further includes a second LC circuit (LC circuit 2) and a third LC circuit (LC circuit 3) composed of an inductor and a capacitor. The LC circuit 2 and the LC circuit 3 are respectively connected with the USB socket. Data pin connection (LC circuit 2 is connected to pin2, LC circuit 3 is connected to pin3), because the LC circuit has the function of absorbing the frequency of the electromagnetic signal, so when the user sends data through the USB data cable, the user can absorb the data transmission through the LC circuit. Octave interference, such as attenuating the signal frequency by 3 or 4 times during data transmission.

It should be noted that FIG. 2 is only an exemplary drawing. In addition to the portion shown in FIG. 2, the USB socket operating circuit 100 also includes other pins connected to the pins 1, pin 2, pin 3, pin 4 and pin 5 of the USB socket 101. There are no restrictions.

Specifically, the switching circuit 102 and the controller 103 in FIG. 2 may be integrated in U301 shown in FIG. 3. When data is transmitted through the data pins of the USB socket 101 through the U301, the ground pin of the USB socket 101 is passed through a Or multiple capacitors are grounded to achieve the equivalent grounding of the cable shield, attenuate the USB frequency and multiplied signals to the maximum, and reduce or eliminate the impact on the RE test.

As shown in FIG. 3, it is another schematic diagram of a USB socket operation circuit provided in an embodiment of the present application. The USB socket operation circuit may include USB101, a capacitor array 104, and U301. Among them, USB101 and capacitor array 104 are shown in FIG. 2. The functions of the USB 101 and the capacitor array 104 are the same, and will not be described again. U301 can include radio frequency (RF) pins RF1 and RF2, CTL pins, enable (EN) pins, useless (NC) pins, power supply (VDD) pins, multiple ground pins (GND1 and GND2) and so on.

Among them, RF1 is equivalent to the contact 2 of the switching circuit 102 in FIG. 2, RF1 can be connected to the ground pin of the USB socket 101, RF2 is equivalent to the contact 1 of the switching circuit 101 in FIG. 2, and RF1 and RF2 can be in CTL. Connected or disconnected under the control of pins,

The CTL pin is equivalent to the controller 103 in FIG. 2 and is used to connect RF1 and RF2 when data transmission is detected on the data pin of the USB socket 101, and no data transmission is detected on the data pin of the USB socket 101. At this time, disconnect RF1 and RF2.

The functions of the enable (EN) pin, the useless (NC) pin, the power supply (VDD) pin, and multiple ground pins (GND1 and GND2) can be referred to in the prior art, and will not be described again.

In this way, when the user inserts the USB data cable into the USB interface of the USB socket and transmits data through the data pins of the USB socket, the CTL pin of U301 communicates with RF1 and RF2, and the ground pin of the USB socket is grounded through a capacitor. Because the capacitor has the physical characteristics of blocking AC and DC, it can transmit the multiplied signal generated by the USB interface during data transmission to the ground through the ground capacitor to achieve equivalent grounding for the cable shielding layer and maximize attenuation of the USB frequency and frequency Signal to reduce or eliminate the impact on the RE test. When there is no data transmission on the USB interface, the CTL pin of U301 disconnects the connection between RF1 and RF2, so that the ground capacitor is not connected to the transmission link. The shell of the USB socket is equivalent to an open circuit. For the antenna, etc. High-impedance state without affecting antenna performance.

FIG. 4 shows a block diagram of a terminal. As shown in FIG. 4, the terminal may include a USB socket running circuit 100. The USB socket running circuit 100 may be the USB socket running circuit shown in FIG. 2 or FIG. 3. The operating circuit of the USB cradle shown in FIG. 2 or FIG. 3 has the same function and will not be described again.

It should be noted that the device structure shown in FIG. 4 does not constitute a limitation on the terminal device, and may include more or fewer parts than shown in the figure, or some parts may be combined, or different parts may be arranged. Although not shown, the terminal device may further include a module such as a display, a battery, a camera, a Bluetooth module, a global positioning system (Global Positioning System, GPS), etc., and details are not described herein again.

Through the description of the above embodiments, those skilled in the art can clearly understand that, for the convenience and brevity of the description, only the division of the above functional modules is used as an example. In practical applications, the above functions can be allocated according to needs. It is completed by different functional modules, that is, the internal structure of the device is divided into different functional modules to complete all or part of the functions described above.

In the several embodiments provided in this application, it should be understood that the disclosed apparatus and method may be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the modules or units is only a logical function division. In actual implementation, there may be another division manner. For example, multiple units or components may be divided. The combination can either be integrated into another device, or some features can be ignored or not implemented. In addition, the displayed or discussed mutual coupling or direct coupling or communication connection may be indirect coupling or communication connection through some interfaces, devices or units, which may be electrical, mechanical or other forms.

The unit described as a separate component may or may not be physically separated, and the component displayed as a unit may be a physical unit or multiple physical units, that is, may be located in one place, or may be distributed to multiple different places. . Some or all of the units may be selected according to actual needs to achieve the objective of the solution of this embodiment.

In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each of the units may exist separately physically, or two or more units may be integrated into one unit. The above integrated unit may be implemented in the form of hardware or in the form of software functional unit.

When the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it may be stored in a readable storage medium. Based on such an understanding, the technical solutions of the embodiments of the present application essentially or partly contribute to the existing technology or all or part of the technical solutions may be embodied in the form of a software product, which is stored in a storage medium The instructions include a number of instructions for causing a device (which can be a single-chip microcomputer, a chip, or the like) or a processor to execute all or part of the steps of the method described in each embodiment of the present application. The foregoing storage medium includes various media that can store program codes, such as a U disk, a mobile hard disk, a ROM, a RAM, a magnetic disk, or an optical disk.

The above is only a specific implementation of this application, but the scope of protection of this application is not limited to this. Any changes or replacements within the technical scope disclosed in this application shall be covered by the scope of protection of this application. . Therefore, the protection scope of this application shall be subject to the protection scope of the claims.

Claims

A universal serial bus USB base operating circuit, characterized in that the USB base operating circuit includes a USB base, a switch circuit, a controller, and a capacitor array. The USB base includes one or more ground pins, and the capacitor array includes one Or multiple ground capacitors;

One end of the switch circuit is connected to a first ground pin included in the USB socket, and the other end of the switch circuit is connected to the capacitor array;

The controller is configured to control the switch circuit to communicate when there is data transmission on the USB socket, and to control the switch circuit to be disconnected when there is no data transmission on the USB socket.
The USB socket operating circuit according to claim 1, wherein:

The USB socket operating circuit further includes a first LC circuit, and the first LC circuit is composed of an inductor and a capacitor;

One end of the first LC circuit is connected to a second ground pin of the USB socket, and the other end of the first LC circuit is grounded.
The USB socket operating circuit according to claim 1 or 2, wherein:

The USB socket operating circuit further includes a second LC circuit, and the USB socket further includes a data pin;

One end of the second LC circuit is connected to a data pin of the USB socket, and the other end of the second LC circuit is grounded.
A terminal, characterized in that the terminal comprises: a universal serial bus USB socket operating circuit according to claim 1 to claim 3.