CN114156853A

CN114156853A - Terminal and charging protection circuit thereof

Info

Publication number: CN114156853A
Application number: CN202210027267.4A
Authority: CN
Inventors: 黄发良
Original assignee: Beijing Xiaomi Mobile Software Co Ltd
Current assignee: Beijing Xiaomi Mobile Software Co Ltd
Priority date: 2022-01-11
Filing date: 2022-01-11
Publication date: 2022-03-08

Abstract

The application provides a terminal and a charging protection circuit thereof, and belongs to the technical field of electronics. The charging protection circuit comprises a first clamping circuit, a second clamping circuit and an overvoltage protection circuit. The first clamping circuit can clamp a larger voltage generated at a charging pin of the charging interface to a smaller voltage. The overvoltage protection circuit can cut off the coupling of the charging pin and the rear-stage circuit based on the clamped small voltage, so that the voltage at the charging pin cannot be transmitted to the rear-stage circuit. The second clamping circuit can clamp the larger voltage of the backward circuit flowing to the overvoltage protection circuit to the lower voltage. So, not only can reliably prevent that back stage circuit from to the great voltage of charging the kneck backward flow, the protection kneck components and parts of charging do not damaged, but also can effectively avoid charging great voltage (for example, surge voltage) that the kneck produced and transmit to back stage circuit, and then reduce the risk that back stage circuit is burnt out. Therefore, the charging safety of the terminal is improved.

Description

Terminal and charging protection circuit thereof

Technical Field

The application relates to the technical field of electronics, in particular to a terminal and a charging protection circuit thereof.

Background

With the development of electronic technology, terminals (e.g., mobile phones) are becoming one of the indispensable electronic devices in people's daily work and life.

Currently, a terminal generally includes a charging interface coupled to a subsequent circuit (e.g., a display driving circuit) and the subsequent circuit. When the terminal needs to be charged, the charging interface of the terminal can be coupled to a power supply, and the charging interface can charge the rear-stage circuit based on the power supply voltage provided by the power supply.

However, the charging interface is affected by the unavoidable surge voltage, so that the problem of burning the post-stage circuit is easily caused in the charging process, and the charging safety is poor.

Disclosure of Invention

The embodiment of the application provides a terminal and a charging protection circuit thereof, which can solve the problem of poor charging safety of the terminal in the related art. The technical scheme is as follows:

in one aspect, a charging protection circuit of a terminal is provided, the terminal having a charging interface and a post-stage circuit, the charging protection circuit comprising: the overvoltage protection circuit comprises a first clamping circuit, a second clamping circuit and an overvoltage protection circuit;

the first clamping circuit is respectively coupled with an input pin of the overvoltage protection circuit and a pull-down power supply end and is also used for being coupled with a charging pin of the charging interface; the second clamping circuit is respectively coupled with an output pin of the overvoltage protection circuit and the pull-down power supply end and is also used for being coupled with the post-stage circuit; the input pin of the overvoltage protection circuit is also used for being coupled with the charging pin, and the output pin of the overvoltage protection circuit is also used for being coupled with the post-stage circuit;

the first clamping circuit is used for clamping the voltage at the charging pin to a first clamping voltage based on a pull-down power supply signal provided by the pull-down power supply end if the voltage at the charging pin is greater than or equal to a first voltage threshold; the overvoltage protection circuit is used for controlling the input pin and the output pin of the overvoltage protection circuit to be disconnected based on the first clamping voltage, and the first clamping voltage is smaller than the first voltage threshold;

the second clamping circuit is used for clamping the voltage at the output pin of the overvoltage protection circuit to a second clamping voltage based on the pull-down power supply signal if the voltage at the output pin of the overvoltage protection circuit is greater than or equal to a second voltage threshold, wherein the second clamping voltage is less than the second voltage threshold.

Optionally, the first clamping circuit includes: the first voltage threshold is the reverse working voltage of the first transient diode, and the first clamping voltage is the maximum clamping voltage of the first transient diode;

one end of the first transient diode is coupled with the input pin of the overvoltage protection circuit and is further used for being coupled with the charging pin, and the other end of the first transient diode is coupled with the pull-down power supply end.

Optionally, the first transient diode is a bidirectional transient diode.

Optionally, the second clamping circuit includes: a second transient diode, the second voltage threshold being a reverse operating voltage of the second transient diode, the second clamping voltage being a maximum clamping voltage of the second transient diode;

one end of the second transient diode is coupled to the output pin of the overvoltage protection circuit and is further used for being coupled to the post-stage circuit, and the other end of the second transient diode is coupled to the pull-down power supply terminal.

Optionally, the second transient diode is a bidirectional transient diode.

Optionally, the charging protection circuit further includes: a filter circuit;

the filter circuit is respectively coupled with an input pin of the overvoltage protection circuit and the pull-down power supply end; the filter circuit is used for filtering the voltage at the input pin of the overvoltage protection circuit based on the pull-down power supply signal.

Optionally, the filter circuit includes: a filter capacitor;

one end of the filter capacitor is coupled with an input pin of the overvoltage protection circuit, and the other end of the filter capacitor is coupled with the pull-down power supply end.

Optionally, the overvoltage protection circuit is further configured to control an input pin and an output pin of the overvoltage protection circuit to be turned on if the voltage at the charging pin is smaller than the first voltage threshold, and the voltage at the charging pin is transmitted to the post-stage circuit through the overvoltage protection circuit to charge the post-stage circuit.

Optionally, the overvoltage protection circuit is an overvoltage protection chip.

Optionally, the pull-down power supply end is a ground end.

Optionally, the charging interface is a universal serial bus charging interface.

In another aspect, a terminal is provided, which includes: charge interface, back stage circuit and as above-mentioned aspect charge protection circuit, charge protection circuit includes: the overvoltage protection circuit comprises a first clamping circuit, a second clamping circuit and an overvoltage protection circuit;

the first clamping circuit is respectively coupled with an input pin of the overvoltage protection circuit and a pull-down power supply end and is also used for being coupled with a charging pin of the charging interface; the second clamping circuit is respectively coupled with an output pin of the overvoltage protection circuit and the pull-down power supply end and is also used for being coupled with the post-stage circuit; the input pin of the overvoltage protection circuit is also used for being coupled with the charging pin, and the output pin of the overvoltage protection circuit is also used for being coupled with the post-stage circuit.

To sum up, the technical solution provided by the embodiment of the present application has at least the following beneficial effects:

a terminal and a charging protection circuit thereof are provided. The charging protection circuit comprises a first clamping circuit, a second clamping circuit and an overvoltage protection circuit. The first clamping circuit can clamp a larger voltage generated at a charging pin of the charging interface to a smaller voltage. The overvoltage protection circuit can cut off the coupling of the charging pin and the rear-stage circuit based on the clamped small voltage, so that the voltage at the charging pin cannot be transmitted to the rear-stage circuit. The second clamping circuit can clamp the larger voltage of the backward circuit flowing to the overvoltage protection circuit to the lower voltage. So, not only can reliably prevent that back stage circuit from to the great voltage of charging the kneck backward flow, the protection kneck components and parts of charging do not damaged, but also can effectively avoid charging great voltage (for example, surge voltage) that the kneck produced and transmit to back stage circuit, and then reduce the risk that back stage circuit is burnt out. Therefore, the charging safety of the terminal is improved.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to be able to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a charging protection circuit of a terminal according to an embodiment of the present disclosure;

fig. 2 is a schematic structural diagram of a charging protection circuit of another terminal according to an embodiment of the present disclosure;

fig. 3 is a schematic structural diagram of a charging protection circuit of another terminal according to an embodiment of the present disclosure;

fig. 4 is a schematic structural diagram of a terminal according to an embodiment of the present application;

fig. 5 is a schematic structural diagram of another terminal provided in an embodiment of the present application;

fig. 6 is a schematic structural diagram of another terminal provided in the embodiment of the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

Currently, the power source coupled to the charging interface of the terminal includes: the socket class fixed power that inserts the commercial power, or the precious portable power source that charges of similar. Also, the charging interface of the terminal is generally coupled with a stationary power source through a charging facility including a charging line and a charging connector, and is coupled with a mobile power source through the charging line.

However, no matter which kind of power supply, through detection, a large surge voltage is easily generated at the charging interface at the moment when the power supply is powered on the charging interface of the terminal, or in a hot plug (i.e., hot plugging) process, or under the influence of static electricity. The large surge voltage is further transmitted to the rear-stage circuit of the terminal, so that the rear-stage circuit is burnt out, and a potential risk of fire is caused. In addition, except for burning out the rear-stage circuit, when the rear-stage circuit at the terminal works unstably, the voltage of the rear-stage circuit is easy to flow backwards to the charging interface, so that components at the charging interface of the terminal are damaged. Therefore, the charging safety of the terminal is low, and the product quality of the terminal is poor.

Accordingly, the present disclosure provides a charging protection circuit coupled between a charging interface of a terminal and a post-stage circuit. This charging protection circuit not only can effectively solve great surge voltage and transmit to the back level circuit and lead to the problem that back level circuit is burnt out, can reliably avoid the voltage of back level circuit to flow backward to the kneck that charges moreover, realizes the protection to the kneck components and parts that charge to promote the product quality at terminal.

Fig. 1 is a schematic structural diagram of a charging protection circuit of a terminal according to an embodiment of the present disclosure. As shown in fig. 1, the terminal generally has a charging interface J1 and a subsequent stage circuit 11. The charging protection circuit 00 of the terminal includes: the circuit comprises a first clamping circuit 01, a second clamping circuit 02 and an overvoltage protection circuit 03.

The first clamping circuit 01 is coupled to the input pin IN and the pull-down power supply terminal of the overvoltage protection circuit 03, and is further configured to be coupled to the charging pin VBUS of the charging interface J1. The second clamping circuit 02 is coupled to the output pin OUT of the overvoltage protection circuit 03 and the pull-down power supply terminal, respectively, and is further configured to be coupled to the post-stage circuit 11. The input pin IN of the overvoltage protection circuit 03 is further configured to be coupled to the charging pin VBUS, and the output pin OUT of the overvoltage protection circuit 03 is further configured to be coupled to the post-stage circuit 11.

That is, as shown in fig. 1, the overvoltage protection circuit 03 is connected in series between the charging pin VBUS and the subsequent stage circuit 11, the first clamp circuit 01 is connected in series between a connection line between the overvoltage protection circuit 03 and the charging pin VBUS and the pull-down power supply terminal, and the second clamp circuit 02 is connected in series between the connection line between the overvoltage protection circuit 03 and the subsequent stage circuit 11 and the pull-down power supply terminal. Optionally, the pull-down power source terminal shown in fig. 1 is a ground terminal Gnd.

Based on the above coupling relationship, the first clamping circuit 01 is configured to clamp the voltage at the charging pin VBUS to a first clamping voltage based on a pull-down power supply signal provided by a pull-down power supply terminal if the voltage at the charging pin VBUS is greater than or equal to a first voltage threshold, and the first clamping voltage is less than the first voltage threshold. For example, the first clamping circuit 01 may release the voltage at the charging pin VBUS to the pull-down power source terminal, thereby clamping the voltage at the charging pin VBUS. The overvoltage protection circuit 03 is configured to control the input pin IN and the output pin OUT of the overvoltage protection circuit 03 to be disconnected based on the first clamping voltage.

That is, the first clamping circuit 01 may clamp the voltage at the charging pin VBUS to a lower voltage when the voltage at the charging pin VBUS is larger, so that the overvoltage protection circuit 03 disconnects the charging pin VBUS from the subsequent circuit 11 based on the lower voltage, that is, cuts off a path of the charging interface J1 for charging the subsequent circuit 11. Further, the larger voltage generated at the charging pin VBUS is not transmitted to the rear-stage circuit 11, and the rear-stage circuit 11 is not burned. Therefore, the first voltage threshold can be flexibly set by referring to the surge voltage so as to solve the problem that the larger surge voltage is transmitted to the rear-stage circuit to cause the rear-stage circuit to be burnt.

The second clamping circuit 02 is configured to clamp the voltage at the output pin OUT of the overvoltage protection circuit 03 to a second clamping voltage based on the pull-down power supply signal if the voltage at the output pin OUT of the overvoltage protection circuit 03 is greater than or equal to a second voltage threshold, and the second clamping voltage is less than the second voltage threshold. For example, the second clamping circuit 02 may release the voltage at the output pin OUT of the overvoltage protection circuit 03 to the pull-down power supply terminal, thereby clamping the voltage at the output pin OUT of the overvoltage protection circuit 03.

As can be seen from the structural coupling relationship shown in fig. 1, in the embodiment of the present application, the voltage clamped by the second clamping circuit 02 may be: the voltage of the rear-stage circuit 11 flowing backward to the charging pin J1 through the output pin OUT of the overvoltage protection circuit 03, that is, the voltage of the rear-stage circuit 11 flowing backward to the output pin OUT of the overvoltage protection circuit 03. That is, the second clamping circuit 02 can clamp the backward voltage to a lower voltage when the post-stage circuit 11 backward flows the voltage to the output pin OUT of the overvoltage protection circuit 03, so as to effectively solve the problem that the backward voltage directly flows to the charging interface J1, which causes the damage of the device at the charging interface J1.

Alternatively, the function performed by the overvoltage protection circuit 03 based on the first clamping voltage may be performed after the overvoltage protection circuit 03 is in the operating state. As such, the first clamp voltage may be within the input voltage range that triggers the overvoltage protection circuit 03 to begin operation. Furthermore, the overvoltage protection circuit 03 can have a maximum withstand voltage below which the overvoltage protection circuit 03 cannot be damaged. The second clamping voltage may be less than the maximum withstand voltage. In this way, reliable protection of the overvoltage protection circuit 03 can also be achieved.

In summary, the embodiment of the present application provides a charging protection circuit for a terminal, where the charging protection circuit includes a first clamp circuit, a second clamp circuit, and an overvoltage protection circuit. The first clamping circuit can clamp a larger voltage generated at a charging pin of the charging interface to a smaller voltage. The overvoltage protection circuit can cut off the coupling of the charging pin and the rear-stage circuit based on the clamped small voltage, so that the voltage at the charging pin cannot be transmitted to the rear-stage circuit. The second clamping circuit can clamp the larger voltage of the backward circuit flowing to the overvoltage protection circuit to the lower voltage. So, not only can reliably prevent that back stage circuit from to the great voltage of charging the kneck backward flow, the protection kneck components and parts of charging do not damaged, but also can effectively avoid charging great voltage (for example, surge voltage) that the kneck produced and transmit to back stage circuit, and then reduce the risk that back stage circuit is burnt out. Therefore, the charging safety of the terminal is improved.

Optionally, with reference to fig. 1, IN this embodiment of the application, the overvoltage protection circuit 03 may be further configured to control the input pin IN and the output pin OUT of the overvoltage protection circuit 03 to be turned on if the voltage at the charging pin VBUS is smaller than the first voltage threshold, and accordingly, the voltage at the charging pin VBUS may be transmitted to the subsequent-stage circuit 11 through the overvoltage protection circuit 03 to charge the subsequent-stage circuit 11.

That is, when the voltage at the charging pin VBUS of the charging pin J1 is small (e.g., has not yet reached the surge voltage or has recovered from a large surge voltage to a small normal voltage), the first clamping circuit 01 may not operate, and the input pin IN and the output pin OUT of the overvoltage protection circuit 03 may be IN a conductive state, i.e., may be automatically turned on, so that the charging pin VBUS is communicated with the subsequent stage circuit 11. Further, the voltage at the charging pin VBUS can be reliably transmitted to the subsequent circuit 11 to charge the subsequent circuit 11. In addition, the second clamping circuit 02 may not operate when the post-stage circuit 11 does not reverse the voltage, i.e., the voltage at the output pin OUT of the overvoltage protection circuit 03 is less than the second voltage threshold.

Fig. 2 is a schematic structural diagram of a charging protection circuit of another terminal according to an embodiment of the present disclosure. As shown in fig. 2, the charging protection circuit 00 provided in the embodiment of the present application may further include: and a filter circuit 04.

The filter circuit 04 may be coupled to the input pin IN of the overvoltage protection circuit 03 and the pull-down power supply terminal, respectively. Since the aforementioned embodiment describes that the input pin IN of the overvoltage protection circuit 03 is coupled to the charging pin VBUS of the charging interface J1 and coupled to the first clamp circuit 01, it can be seen from fig. 2 that the filter circuit 04 is actually coupled to the first clamp circuit 01 and the charging pin VBUS of the charging interface J1. That is, the filter circuit 04 is connected in series between the overvoltage protection circuit 03 and the connection line of the charging pin VBUS and the pull-down power supply terminal, as with the first clamp circuit 01.

The filter circuit 04 may be configured to filter the voltage at the input pin IN of the overvoltage protection circuit 03 based on the pull-down power signal. IN this way, the accuracy of the signal transmitted to the input pin IN of the overvoltage protection circuit 03 can be improved. Further, reliable operation of the overvoltage protection circuit 03 is ensured.

Optionally, as known from the above description of the embodiment and the coupling manner shown IN fig. 2, the voltage at the input pin IN of the filtered overvoltage protection circuit 03 herein includes: the voltage directly comes from the voltage at the charging interface VBUS, and the first clamping circuit 01 clamps the voltage at the charging interface VBUS.

Fig. 3 is a schematic structural diagram of a charging protection circuit of another terminal according to an embodiment of the present disclosure. As shown in fig. 3, the first clamp circuit 01 may include: a first Transient Voltage Super (TVS) TVS 1. Accordingly, the first voltage threshold may be a reverse operating voltage of the first transient diode TVS1, and the first clamping voltage may be a maximum clamping voltage of the first transient diode TVS 1. In addition, as described in the above embodiments, the first clamping voltage may be within the input voltage range of the overvoltage protection circuit 03. Therefore, the model of the first transient diode TVS1 can be flexibly selected based on the input voltage range of the overvoltage protection circuit 03, so that the maximum clamping voltage of the selected first transient diode TVS1 is within the input voltage range of the overvoltage protection circuit 03, and reliable operation of the overvoltage protection circuit 03 is ensured.

One end of the first transient diode TVS1 may be coupled to the input pin IN of the overvoltage protection circuit 03, and may also be configured to be coupled to the charging pin VBUS. The other terminal of the first transient diode TVS1 may be coupled to a pull-down power supply terminal.

Alternatively, as can be seen with continued reference to fig. 3, the second clamp circuit 02 may include: a second transient diode TVS 2. Accordingly, the second voltage threshold may be a reverse operating voltage of the second transient diode TVS2, and the second clamping voltage may be a maximum clamping voltage of the second transient diode TVS 2. In addition, in conjunction with the above embodiment, the second clamping voltage may be smaller than the maximum withstand voltage of the overvoltage protection circuit 03. Therefore, the model of the second transient diode TVS2 can be flexibly selected based on the maximum withstand voltage of the overvoltage protection circuit 03, so that the selected maximum clamping voltage of the second transient diode TVS2 is smaller than the maximum withstand voltage of the overvoltage protection circuit 03.

One end of the second transient diode TVS2 may be coupled to the output pin OUT of the overvoltage protection circuit 03 and may also be configured to be coupled to the post-stage circuit 11, and the other end of the second transient diode TVS2 may be coupled to a pull-down power supply terminal.

Alternatively, referring to fig. 3, the first transient diode TVS1 provided in the embodiment of the present application may be a bidirectional transient diode (also referred to as a bipolar transient diode). The second transient diode TVS2 may also be a bi-directional transient diode. Of course, in some other embodiments, the first transient diode TVS1 and/or the second transient diode TVS2 may also be unidirectional transient diodes.

The bidirectional transient diode is equivalent to a diode in which the cathodes of two zener diodes are connected, that is, the bidirectional transient diode can be regarded as having two cathodes and two anodes. Referring to fig. 3, for example, the first transient diode TVS1 is a bidirectional transient diode, one positive electrode of the bidirectional transient diode may be coupled to the input pin IN and the charging pin VBUS of the overvoltage protection circuit 03, respectively, and the other positive electrode of the bidirectional transient diode may be coupled to the pull-down power source terminal. The unidirectional transient diode has only one positive electrode and one negative electrode, and IN conjunction with fig. 3, taking the first transient diode TVS1 as the unidirectional transient diode as an example, the positive electrode of the unidirectional transient diode may be coupled to the input pin IN and the charging pin VBUS of the overvoltage protection circuit 03, respectively, and the negative electrode of the unidirectional transient diode may be coupled to the pull-down power source terminal. Bidirectional transient diodes are commonly used in alternating current scenarios; unidirectional transient diodes are commonly used in dc scenarios.

Optionally, as can be seen with continued reference to fig. 3, the filter circuit 04 may include: a filter capacitor C1.

One end of the filter capacitor C1 may be coupled to the input pin IN of the overvoltage protection circuit 03, and the other end of the filter capacitor C1 may be coupled to the pull-down power supply terminal.

Optionally, as shown in fig. 3, the overvoltage Protection circuit 03 according to the embodiment of the present application may be an overvoltage Protection (OVP) chip. Also, as can be seen from fig. 3, the OVP chip has a plurality of ground terminals GND (4 IN fig. 3) IN addition to the input pin IN and the output pin OUT, and each ground terminal GND is coupled to the ground terminal GND, i.e., grounded.

Alternatively, as can be seen with continued reference to fig. 3, the pull-down power source terminal described in the embodiment of the present application may be the ground terminal Gnd. Of course, in other embodiments, the pull-down power source terminal may be a pull-down power source terminal capable of providing a lower potential, such as VSS. Note that fig. 3 does not show the subsequent stage circuit 11.

Optionally, the charging interface J1 described in the embodiment of the present application may be a Universal Serial Bus (USB) charging interface. For example, the charging interface J1 may be a C-Type charging interface shown in any one of fig. 1 to 3, and may be simply referred to as a Type-C charging interface.

As can be seen from FIG. 1 to FIG. 3, the Type-C charging interface has 4 charging pins VBUS, which are VBUS/A4, VBUS/B9, VBUS/A9 and VBUS/B4. In addition, the Type-C charging interface has 4 ground pins GND/A1, GND/B12, GND/B1 and GND/A12, the 4 ground pins being coupled to ground GND. There are also 2 Channel Configuration (CC) pins CC1/A5 and CC2/B5, the Channel Configuration pin CC1/A5 is grounded through resistor R1, and the Channel Configuration pin CC2/B5 is grounded through resistor R2. There are also 2 Side Band Use (SBU) pins SBU1/A8 and SBU2/B8, 2 positive differential signal pins DP1/A6 and DP2/B6, and 2 negative differential signal pins DN1/A7 and DN 2/B7. In addition to the above-mentioned pins, other pins, such as a high-speed signal transmission pin TX, may be provided, which is not described in this embodiment.

Optionally, the charging interface J1 described in this embodiment of the application may be a dc charging interface, that is, the charging protection circuit 00 may be applied to a dc charging interface outlet, so as to effectively solve the problem that the post-stage circuit 11 is burned due to surge voltage or overvoltage generated at an electrostatic moment, an electrification moment or in a hot plug process, and also prevent the post-stage circuit 11 from flowing back voltage to the charging interface J1, thereby protecting components at the charging interface J1. Thereby effectively promoting the product quality of the terminal.

Fig. 4 is a schematic structural diagram of a terminal according to an embodiment of the present application. As shown in fig. 4, the terminal 10 includes: a charging interface J1, a subsequent stage circuit 11, and a charging protection circuit 00 as shown in any one of fig. 1 to 3. Also, as can be seen with reference to fig. 1, the charge protection circuit 00 includes: the circuit comprises a first clamping circuit 01, a second clamping circuit 02 and an overvoltage protection circuit 03.

The first clamping circuit 01 is coupled to an input pin IN of the overvoltage protection circuit 03, a pull-down power supply terminal, and a charging pin VBUS of the charging interface J1. The second clamping circuit 02 is coupled to the output pin OUT of the overvoltage protection circuit 03, the pull-down power supply terminal, and the post-stage circuit 11, respectively. The input pin IN of the overvoltage protection circuit 03 is further coupled to the charging pin VBUS, and the output pin OUT of the overvoltage protection circuit 03 is further coupled to the post-stage circuit 11. That is, as shown in fig. 4, the charging protection circuit 00 may be connected between the charging interface J1 and the rear-stage circuit 11 to control the on/off state between the charging interface J1 and the rear-stage circuit 11.

Optionally, the post-stage circuit 11 may include: a display driving circuit, a speaker driving circuit, a microphone driving circuit, a fingerprint acquisition circuit, and the like, as a series of circuit devices that may be provided to the terminal 10.

Optionally, the terminal 10 described in the embodiment of the present application may be an electronic device such as a mobile phone, a tablet, a notebook computer, or a digital camera. For example, taking the terminal 10 as a mobile phone as an example, fig. 5 shows a schematic configuration diagram of the terminal. Referring to fig. 5, it can be seen that, for the mobile phone, the charging interface J1 is generally located at the lower part. In the embodiment of the present application, the charging interface J1 may be coupled to the subsequent circuit 11 through the charging protection circuit 00, so as to improve the safety of charging the subsequent circuit 11.

Fig. 6 shows a block diagram of a terminal 600 according to an exemplary embodiment of the present application. The terminal 600 may be a portable mobile terminal such as: a smart phone, a tablet computer, a motion Picture Experts Group Audio Layer 3 (MP 3 player), a motion Picture Experts Group Audio Layer 4 (MP 4 player), a notebook computer or a desktop computer. The terminal 600 may also be referred to by other names such as user equipment, portable terminal, laptop terminal, desktop terminal, etc.

In general, the terminal 600 includes: a processor 601 and a memory 602.

The processor 601 may include one or more processing cores, such as a 4-core processor, an 8-core processor, and so on. The processor 601 may be implemented in at least one hardware form of Digital Signal Processing (DSP), Field-Programmable Gate Array (FPGA), and Programmable Logic Array (PLA). The processor 601 may also include a main processor and a coprocessor, where the main processor is a processor for Processing data in an awake state, and is also called a Central Processing Unit (CPU); a coprocessor is a low power processor for processing data in a standby state. In some embodiments, the processor 601 may be integrated with a Graphics Processing Unit (GPU) which is responsible for rendering and drawing the content required to be displayed by the display screen. In some embodiments, processor 601 may also include an Artificial Intelligence (AI) processor for processing computational operations related to machine learning.

The memory 602 may include one or more computer-readable storage media, which may be non-transitory. The memory 602 may also include high-speed random access memory, as well as non-volatile memory, such as one or more magnetic disk storage devices, flash memory storage devices. In some embodiments, a non-transitory computer readable storage medium in memory 602 is used to store at least one instruction for execution by processor 601 to implement the functions of a desired implementation.

In some embodiments, the terminal 600 may further optionally include: a peripheral interface 603 and at least one peripheral. The processor 601, memory 602, and peripheral interface 603 may be connected by buses or signal lines. Various peripheral devices may be connected to the peripheral interface 603 via a bus, signal line, or circuit board. Specifically, the peripheral device includes: at least one of a radio frequency circuit 604, a display 605, a camera assembly 606, an audio circuit 607, a positioning component 608, and a power supply 609.

The peripheral interface 603 may be used to connect at least one Input/Output (I/O) related peripheral to the processor 601 and the memory 602. In some embodiments, the processor 601, memory 602, and peripheral interface 603 are integrated on the same chip or circuit board; in some other embodiments, any one or two of the processor 601, the memory 602, and the peripheral interface 603 may be implemented on a separate chip or circuit board, which is not limited in this embodiment.

The Radio Frequency circuit 604 is used for receiving and transmitting Radio Frequency (RF) signals, also called electromagnetic signals. The radio frequency circuitry 604 communicates with communication networks and other communication devices via electromagnetic signals. The rf circuit 604 converts an electrical signal into an electromagnetic signal to transmit, or converts a received electromagnetic signal into an electrical signal. Optionally, the radio frequency circuit 604 comprises: an antenna system, an RF transceiver, one or more amplifiers, a tuner, an oscillator, a digital signal processor, a codec chipset, a subscriber identity module card, and so forth. The radio frequency circuitry 604 may communicate with other terminals via at least one wireless communication protocol. The wireless communication protocols include, but are not limited to: the world wide web, metropolitan area networks, intranets, generations of mobile communication networks (2G, 3G, 4G, and 5G), Wireless local area networks, and/or Wireless Fidelity (WiFi) networks. In some embodiments, rf circuitry 604 may also include Near Field Communication (NFC) related circuitry, which is not limited in this application.

The display 605 is used to display a User Interface (UI). The UI may include graphics, text, icons, video, and any combination thereof. When the display screen 605 is a touch display screen, the display screen 605 also has the ability to capture touch signals on or over the surface of the display screen 605. The touch signal may be input to the processor 601 as a control signal for processing. At this point, the display 605 may also be used to provide virtual buttons and/or a virtual keyboard, also referred to as soft buttons and/or a soft keyboard. In some embodiments, the display 605 may be one, disposed on the front panel of the terminal 600; in other embodiments, the display 605 may be at least two, respectively disposed on different surfaces of the terminal 600 or in a folded design; in other embodiments, the display 605 may be a flexible display disposed on a curved surface or a folded surface of the terminal 600. Even more, the display 605 may be arranged in a non-rectangular irregular pattern, i.e., a shaped screen. The Display 605 may be made of Liquid Crystal Display (LCD), Organic Light-Emitting Diode (OLED), or the like.

The camera assembly 606 is used to capture images or video. Optionally, camera assembly 606 includes a front camera and a rear camera. Generally, a front camera is disposed at a front panel of the terminal, and a rear camera is disposed at a rear surface of the terminal. In some embodiments, the number of the rear cameras is at least two, and each rear camera is any one of a main camera, a depth-of-field camera, a wide-angle camera and a telephoto camera, so that the main camera and the depth-of-field camera are fused to realize a background blurring function, and the main camera and the wide-angle camera are fused to realize panoramic shooting and a Virtual Reality (VR) shooting function or other fusion shooting functions. In some embodiments, camera assembly 606 may also include a flash. The flash lamp can be a monochrome temperature flash lamp or a bicolor temperature flash lamp. The double-color-temperature flash lamp is a combination of a warm-light flash lamp and a cold-light flash lamp, and can be used for light compensation at different color temperatures.

Audio circuitry 607 may include a microphone and a speaker. The microphone is used for collecting sound waves of a user and the environment, converting the sound waves into electric signals, and inputting the electric signals to the processor 601 for processing or inputting the electric signals to the radio frequency circuit 604 to realize voice communication. For the purpose of stereo sound collection or noise reduction, a plurality of microphones may be provided at different portions of the terminal 600. The microphone may also be an array microphone or an omni-directional pick-up microphone. The speaker is used to convert electrical signals from the processor 601 or the radio frequency circuit 604 into sound waves. The loudspeaker can be a traditional film loudspeaker or a piezoelectric ceramic loudspeaker. When the speaker is a piezoelectric ceramic speaker, the speaker can be used for purposes such as converting an electric signal into a sound wave audible to a human being, or converting an electric signal into a sound wave inaudible to a human being to measure a distance. In some embodiments, audio circuitry 607 may also include a headphone jack.

The positioning component 608 is used to locate the current geographic Location of the terminal 600 for navigation or Location Based Service (LBS). The Positioning component 608 can be a Positioning component based on the Global Positioning System (GPS) in the united states, the beidou System in china, or the galileo System in russia.

Power supply 609 is used to provide power to the various components in terminal 600. The power supply 609 may be ac, dc, disposable or rechargeable. When the power supply 609 includes a rechargeable battery, the rechargeable battery may be a wired rechargeable battery or a wireless rechargeable battery. The wired rechargeable battery is a battery charged through a wired line, and the wireless rechargeable battery is a battery charged through a wireless coil. The rechargeable battery may also be used to support fast charge technology.

In some embodiments, the terminal 600 also includes one or more sensors 610. The one or more sensors 610 include, but are not limited to: acceleration sensor 611, gyro sensor 612, pressure sensor 613, fingerprint sensor 614, optical sensor 615, and proximity sensor 616.

The acceleration sensor 611 may detect the magnitude of acceleration in three coordinate axes of the coordinate system established with the terminal 600. For example, the acceleration sensor 611 may be used to detect components of the gravitational acceleration in three coordinate axes. The processor 601 may control the display screen 605 to display the user interface in a landscape view or a portrait view according to the gravitational acceleration signal collected by the acceleration sensor 611. The acceleration sensor 611 may also be used for acquisition of motion data of a game or a user.

The gyro sensor 612 may detect a body direction and a rotation angle of the terminal 600, and the gyro sensor 612 and the acceleration sensor 611 may cooperate to acquire a 3D motion of the user on the terminal 600. The processor 601 may implement the following functions according to the data collected by the gyro sensor 612: motion sensing (such as changing the UI according to a user's tilting operation), image stabilization at the time of photographing, game control, and inertial navigation.

Pressure sensors 613 may be disposed on the side bezel of terminal 600 and/or underneath display screen 605. When the pressure sensor 613 is disposed on the side frame of the terminal 600, a user's holding signal of the terminal 600 can be detected, and the processor 601 performs left-right hand recognition or shortcut operation according to the holding signal collected by the pressure sensor 613. When the pressure sensor 613 is disposed at the lower layer of the display screen 605, the processor 601 controls the operability control on the UI interface according to the pressure operation of the user on the display screen 605. The operability control comprises at least one of a button control, a scroll bar control, an icon control and a menu control.

The fingerprint sensor 614 is used for collecting a fingerprint of a user, and the processor 601 identifies the identity of the user according to the fingerprint collected by the fingerprint sensor 614, or the fingerprint sensor 614 identifies the identity of the user according to the collected fingerprint. Upon identifying that the user's identity is a trusted identity, the processor 601 authorizes the user to perform relevant sensitive operations including unlocking the screen, viewing encrypted information, downloading software, paying, and changing settings, etc. The fingerprint sensor 614 may be disposed on the front, back, or side of the terminal 600. When a physical button or vendor Logo is provided on the terminal 600, the fingerprint sensor 614 may be integrated with the physical button or vendor Logo.

The optical sensor 615 is used to collect the ambient light intensity. In one embodiment, processor 601 may control the display brightness of display screen 605 based on the ambient light intensity collected by optical sensor 615. Specifically, when the ambient light intensity is high, the display brightness of the display screen 605 is increased; when the ambient light intensity is low, the display brightness of the display screen 605 is adjusted down. In another embodiment, the processor 601 may also dynamically adjust the shooting parameters of the camera assembly 606 according to the ambient light intensity collected by the optical sensor 615.

A proximity sensor 616, also known as a distance sensor, is typically disposed on the front panel of the terminal 600. The proximity sensor 616 is used to collect the distance between the user and the front surface of the terminal 600. In one embodiment, when proximity sensor 616 detects that the distance between the user and the front face of terminal 600 gradually decreases, processor 601 controls display 605 to switch from the bright screen state to the dark screen state; when the proximity sensor 616 detects that the distance between the user and the front face of the terminal 600 is gradually increased, the processor 601 controls the display 605 to switch from the breath-screen state to the bright-screen state.

Those skilled in the art will appreciate that the configuration shown in fig. 6 is not intended to be limiting of terminal 600 and may include more or fewer components than those shown or some components may be combined or a different arrangement of components may be used.

Optionally, the recitation of "a" or "an" and the like in the embodiments of the present application is not intended to be limiting in number, but rather to mean that there is at least one.

Similarly, the word "comprise" or "comprises", and the like, means that the element or item appearing before the word "comprises" or "comprising" covers the element or item listed after the word "comprising" or "comprises" and its equivalents, and does not exclude other elements or items.

"upper", "lower", "left", or "right", etc. are used merely to indicate relative positional relationships, which may also change accordingly when the absolute position of the object being described changes.

"and/or" means that three relationships may exist, e.g., A and/or B, may mean: a exists alone, A and B exist simultaneously, and B exists alone. The character "/" generally indicates that the former and latter associated objects are in an "or" relationship.

The above description is only exemplary of the present application and should not be taken as limiting, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A charge protection circuit (00) of a terminal, the terminal having a charging interface (J1) and a post-stage circuit (11), the charge protection circuit (00) comprising: the circuit comprises a first clamping circuit (01), a second clamping circuit (02) and an overvoltage protection circuit (03);

the first clamping circuit (01) is respectively coupled with an input pin (IN) and a pull-down power supply terminal of the overvoltage protection circuit (03), and is also used for being coupled with a charging pin (VBUS) of the charging interface (J1); the second clamping circuit (02) is respectively coupled with an output pin (OUT) of the overvoltage protection circuit (03) and the pull-down power supply end and is also used for being coupled with the post-stage circuit (11); the input pin (IN) of the overvoltage protection circuit (03) is also used for being coupled with the charging pin (VBUS), and the output pin (OUT) of the overvoltage protection circuit (03) is also used for being coupled with the post-stage circuit (11);

the first clamping circuit (01) is used for clamping the voltage at the charging pin (VBUS) to a first clamping voltage based on a pull-down power supply signal provided by the pull-down power supply terminal if the voltage at the charging pin (VBUS) is greater than or equal to a first voltage threshold; the overvoltage protection circuit (03) is used for controlling an input pin (IN) and an output pin (OUT) of the overvoltage protection circuit (03) to be disconnected based on the first clamping voltage, and the first clamping voltage is smaller than the first voltage threshold value;

the second clamping circuit (02) is configured to clamp the voltage at the output pin (OUT) of the overvoltage protection circuit (03) to a second clamping voltage based on the pull-down power supply signal if the voltage at the output pin (OUT) of the overvoltage protection circuit (03) is greater than or equal to a second voltage threshold, the second clamping voltage being less than the second voltage threshold.

2. The charge protection circuit (00) of claim 1, wherein the first clamp circuit (01) comprises: a first transient diode (TVS1), the first voltage threshold being a reverse operating voltage of the first transient diode (TVS1), the first clamping voltage being a maximum clamping voltage of the first transient diode (TSV 1);

wherein one end of the first transient diode (TVS1) is coupled to the input pin (IN) of the overvoltage protection circuit (03) and is further used for being coupled to the charging pin (VBUS), and the other end of the first transient diode (TVS1) is coupled to the pull-down power supply terminal.

3. The charge protection circuit (00) of claim 2, wherein the first transient diode (TVS1) is a bi-directional transient diode.

4. The charge protection circuit (00) of claim 1, wherein the second clamping circuit (02) comprises: a second transient diode (TVS2), the second voltage threshold being a reverse operating voltage of the second transient diode (TVS2), the second clamping voltage being a maximum clamping voltage of the second transient diode (TVS 2);

wherein, one end of the second transient diode (TVS2) is coupled with the output pin (OUT) of the overvoltage protection circuit (03) and is also used for being coupled with the rear-stage circuit (11), and the other end of the second transient diode (TVS2) is coupled with the pull-down power supply terminal.

5. The charge protection circuit (00) of claim 4, wherein the second transient diode (TVS2) is a bi-directional transient diode.

6. The charge protection circuit (00) according to any one of claims 1 to 5, wherein the charge protection circuit (00) further comprises: a filter circuit (04);

the filter circuit (04) is respectively coupled with an input pin (IN) of the overvoltage protection circuit (03) and the pull-down power supply end; the filter circuit (04) is used for filtering the voltage at the input pin (IN) of the overvoltage protection circuit (03) based on the pull-down power supply signal.

7. The charge protection circuit (00) according to claim 6, wherein the filter circuit (04) comprises: a filter capacitance (C1);

one end of the filter capacitor (C1) is coupled with an input pin (IN) of the overvoltage protection circuit (03), and the other end of the filter capacitor (C1) is coupled with the pull-down power supply terminal.

8. The charge protection circuit (00) according to any one of claims 1 to 5, wherein the over-voltage protection circuit (03) is further configured to control an input pin (IN) and an output pin (OUT) of the over-voltage protection circuit (03) to conduct if the voltage at the charging pin (VBUS) is less than the first voltage threshold, and the voltage at the charging pin (VBUS) is transmitted to the post-stage circuit (11) through the over-voltage protection circuit (03) to charge the post-stage circuit (11).

9. The charging protection circuit (00) according to any one of claims 1 to 5, wherein the overvoltage protection circuit (03) is an overvoltage protection chip.

10. The charge protection circuit (00) according to any one of claims 1 to 5, wherein the pull-down power supply terminal is a ground terminal (GND).

11. The charge protection circuit (00) according to any one of claims 1 to 5, wherein the charging interface (J1) is a universal serial bus charging interface.

12. A terminal, characterized in that the terminal comprises: a charging interface (J1), a post-stage circuit (11), and a charging protection circuit (00) according to any of claims 1 to 11, the charging protection circuit (00) comprising: the circuit comprises a first clamping circuit (01), a second clamping circuit (02) and an overvoltage protection circuit (03);

wherein the first clamping circuit (01) is respectively coupled with an input pin (IN) and a pull-down power supply terminal of the overvoltage protection circuit (03), and is further used for being coupled with a charging pin (VBUS) of the charging interface (J1); the second clamping circuit (02) is respectively coupled with an output pin (OUT) of the overvoltage protection circuit (03) and the pull-down power supply end and is also used for being coupled with the post-stage circuit (11); the input pin (IN) of the overvoltage protection circuit (03) is also used for being coupled with the charging pin (VBUS), and the output pin (OUT) of the overvoltage protection circuit (03) is also used for being coupled with the rear-stage circuit (11).