Multi-path charging circuit and mobile terminal

Abstract

The invention relates to a multi-path charging circuit and a mobile terminal, and the circuit comprises a plurality of charging interfaces which are used for receiving charging input from different power adapters; a plurality of load switches, wherein the IN ends of the load switches are connected to the charging interface; the charging chip is connected to the OUT end of the load switch and is used for receiving the charging current from the OUT end of the load switch so as to charge the battery; and the GPIO port of the microprocessor is connected with the VSYS end of the load switch and is used for receiving the charging state signal from the load switch. According to the multi-path charging circuit and the mobile terminal designed by the invention, power supply requirements in different scenes can be quickly responded through perfect and rich power supply switching logic, and the multi-path charging circuit and the mobile terminal have wide applicability and are suitable for any electronic product needing multi-path charging and OTG switching functions. In addition, according to the scheme, the problems of electric leakage, backward flow, logic judgment errors and the like in the multi-path charging and OTG switching process in the prior art are effectively solved.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic equipment power management, in particular to a multi-path charging circuit and a mobile terminal. Background Art

[0002] In the prior art, with the popularization of electronic devices, their usage scenarios are becoming increasingly diversified, and the demand for multi-power management is also growing. In order to meet the needs of charging and powering external devices in different scenarios, electronic devices need to have multiple charging and discharging interfaces. For example, modern smartphones are usually equipped with a USB Type-C interface, a back BACK_POGO-PIN interface, and a bottom BOTTOM_POGO-PIN interface, which can be charged from a variety of power sources. However, in multi-interface charging scenarios, it is necessary to manage the priority and power paths between different charging interfaces to avoid circulation and backflow problems caused by uncoordinated power paths. Minor circulation and backflow can shorten the life of the power supply or cause heating problems, while severe ones can cause equipment damage or even fire.

[0003] At present, the commonly used charging path switching method circuit is implemented as follows Figure 1 As shown in the figure, the circuit receives external power for charging through two different interfaces (U1 and U2). However, this circuit implementation has potential leakage and backflow risks, which will have a negative impact on the stability and safety of the system. This problem mainly stems from the difference in parasitic parameters of different PCB motherboards, resulting in different distributed capacitance, which in turn causes deviations in the closing and conduction time of the MOS switch, ultimately causing failures.

[0004] Specifically, if Figure 1 As shown in the figure, when both interfaces U1 and U2 are plugged into external power supplies, PMOS tube Q1 and NMOS tube Q2 are turned on, and the external power supply of interface U1 charges the battery through PMOS tube Q1. At the same time, NMOS tube Q5 is turned on, causing NMOS tube Q6, PMOS tube Q3 and PMOS tube Q4 to be turned off. Therefore, the external power supply of interface U2 is cut off and cannot supply power to the battery. When the power supply of interface U1 is unplugged, the gate voltage of NMOS tube Q2 will gradually decrease under the discharge of resistor R2 until it is lower than the threshold voltage V THQ2 When the PMOS tube Q1 and the NMOS tube Q2 are turned off, the gate voltage of the NMOS tube Q6 will increase due to the external power supply U2 and the resistor R4 until it reaches the threshold voltage V THQ6When the NMOS tube Q6 is turned on, the PMOS tube Q3 and the PMOS tube Q4 are also turned on; however, due to the influence of parasitic parameters, the gate voltage of the NMOS tube Q6 may reach the threshold before the gate voltage of the NMOS tube Q2, causing the power supply of the interface U2 to reach the source S and drain D of the PMOS tube Q1 through the PMOS tube Q3 and the PMOS tube Q4, and finally reach the gate of the NMOS tube Q2, so that the NMOS tube Q2 cannot be turned off, and finally the power supply of the interface U2 reaches the interface U1 through the PMOS tube, causing backflow and leakage at the interface U1. For products that need to be mass-produced, this potential failure problem is unacceptable. Summary of the invention

[0005] In order to solve the above problems, the present invention provides a multi-path charging circuit and a mobile terminal that can quickly respond to power requirements in different scenarios.

[0006] In order to achieve the above object, the present invention provides a multi-path charging circuit, comprising:

[0007] Multiple charging ports for receiving charging input from different power adapters;

[0008] Multiple load switches, where the IN terminals of the load switches are connected to the charging interface;

[0009] A charging chip is connected to the OUT terminal of the load switch and is used to receive the charging current from the OUT terminal of the load switch to charge the battery;

[0010] A microprocessor, wherein a GPIO port of the microprocessor is connected to a VSYS terminal of the load switch, and is used to receive a charging status signal from the load switch;

[0011] Multiple Schottky diodes;

[0012] Wherein, the ENN terminal of the load switch U1 is grounded through the resistor R1, the ENN terminal of the load switch U2 is grounded through the resistor R2, and the ENN terminal of the load switch U3 is grounded through the resistor R3;

[0013] The RXN terminal of the load switch U1 is divided into two paths, one of which is connected to the positive electrode of the Schottky diode D1, and the other is connected to the positive electrode of the Schottky diode D3; the cathode of the Schottky diode D1 is connected to the connection node between the load switch U2 and the resistor R2, and the cathode of the Schottky diode D3 is connected to the connection node between the load switch U3 and the resistor R3;

[0014] The RXN terminal of the load switch U2 is connected to the anode of the Schottky diode D2, and the cathode of the Schottky diode D2 is connected to the connection node between the load switch U3 and the resistor R3.

[0015] A further solution is that the resistance values ​​of the resistor R1, the resistor R2 and the resistor R3 are all 4.7K.

[0016] A further solution is that the model of the load switch is AW32102.

[0017] A further solution is to further include a power module connected to the battery, the power module being used to output a voltage to supply power to an external device;

[0018] Each charging interface has a detection terminal, and the microprocessor has an enable terminal that responds to an interrupt signal from the detection terminal;

[0019] When any charging interface is connected to an external device, the corresponding detection terminal generates an interrupt signal, and the microprocessor receives the interrupt signal and performs an interrupt response to pull the level of the corresponding enable terminal high;

[0020] When the level of any one or more enable terminals is pulled high, the microprocessor controls the power module to turn on, and the output voltage supplies power to external devices.

[0021] A further solution is that a current limiting chip for limiting current and an overvoltage protection chip for limiting voltage are connected in series between the power module and the charging interface.

[0022] A further solution is that the model of the current limiting chip is SGM2593, and the model of the overvoltage protection chip is SGM40666.

[0023] A further solution is that the model of the power module is ETA1090A.

[0024] Another aspect of the present invention provides a mobile terminal, comprising the multi-path charging circuit described in the above solution.

[0025] The multi-path charging circuit and mobile terminal designed by the present invention can quickly respond to power requirements in different scenarios through perfect and rich power switching logic, and have wide applicability, and are suitable for any electronic products that require multi-path charging and OTG switching functions. In addition, the solution effectively solves the problems of leakage, backflow, logical judgment errors, etc. in the multi-path charging and OTG switching process in the prior art, improves the power management efficiency and safety of electronic equipment, is suitable for large-scale mass production, and can meet the market demand for high-quality electronic products. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a circuit diagram of existing charging path switching;

[0027] Figure 2 This is a schematic diagram of multi-path charging provided by an embodiment of the present application;

[0028] Figure 3 It is a framework diagram of a multi-path charging circuit provided in an embodiment of the present application;

[0029] Figure 4 This is a connection diagram of a multi-path charging circuit provided in an embodiment of the present application. DETAILED DESCRIPTION

[0030] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0031] Example 1.

[0032] like Figure 1-4 As shown, this embodiment describes a multi-path charging circuit on one hand, the circuit comprising: a plurality of charging interfaces I1-3, for receiving charging inputs from different power adapters;

[0033] Multiple load switches U1-3, where the IN terminals of the load switches U1-3 are connected to the charging interface I1-3;

[0034] The charging chip 100 is connected to the OUT terminal of the load switch U1 - 3 and is used to receive the charging current from the OUT terminal of the load switch U1 - 3 to charge the battery 200;

[0035] A microprocessor 300, wherein a GPIO port of the microprocessor 300 is connected to a VSYS terminal of the load switch U1-3, and is used to receive a charging status signal from the load switch U1-3;

[0036] Multiple Schottky diodes D1-3;

[0037] Wherein, the ENN terminal of the load switch U1 is grounded through the resistor R1, the ENN terminal of the load switch U2 is grounded through the resistor R2, and the ENN terminal of the load switch U3 is grounded through the resistor R3;

[0038] The RXN terminal of the load switch U1 is divided into two paths, one of which is connected to the positive electrode of the Schottky diode D1, and the other is connected to the positive electrode of the Schottky diode D3; the cathode of the Schottky diode D1 is connected to the connection node between the load switch U2 and the resistor R2, and the cathode of the Schottky diode D3 is connected to the connection node between the load switch U3 and the resistor R3;

[0039] The RXN terminal of the load switch U2 is connected to the positive electrode of the Schottky diode D2, and the negative electrode of the Schottky diode D2 is connected to the connection node between the load switch U3 and the resistor R3. In this embodiment, the resistance values ​​of the resistors R1, R2 and R3 are all 4.7K.

[0040] Taking a mobile phone as an example, this embodiment is specifically applied to a mobile phone terminal equipped with three peripheral interfaces: a BOTTOM_POGO-PIN interface corresponding to the charging interface I1, a BACK_POGO-PIN interface corresponding to the charging interface I2, and a TYPE-C interface corresponding to the charging interface I3.

[0041] In different usage scenarios, different external power adapters can be connected to charge the mobile phone terminal separately: the microprocessor 300 controls the switch state of the load switch U1-3 in real time according to the charging state signal of the load switch U1-3, thereby realizing the priority management of different charging interfaces to ensure charging efficiency and safety. For example, when the mobile phone is connected to the bottom charging interface and the back charging interface at the same time, the microprocessor 300 will choose to use the bottom charging interface for charging first according to the preset priority rules to ensure the best charging efficiency.

[0042] Specifically, see Figure 3 and Figure 4 As shown, taking a mobile phone as an example, the working principle of the multi-path charging circuit is described in detail, wherein the model of the load switch U1-3 is AW32102.

[0043] Scenario 1: Connect the power adapter to the BOTTOM_POGO-PIN interface (charging interface I1).

[0044] When the BOTTOM_POGO-PIN interface (charging interface I1) is connected to the power adapter, the IN terminal of the load switch U1 receives a 5V voltage. Since the pull-down resistor R1 at the ENN terminal is 4.7K, the voltage at the ENN terminal is 0V, that is, a low level. According to the characteristics of the load switch U1, when the ENN terminal is at a low level, the RXN terminal signal RXN_BOTTOM is flipped to a high level, the VSYS terminal signal BOTTOM_SNS is at a high level, and is transmitted to the GPIO port of the microprocessor 300. The system generates a charging response, and the OUT terminal signal VBUS_IN of the load switch U1 is 5V, and the power supply 5V is transmitted to the charging chip 100 to charge the battery 200.

[0045] At the same time, the RXN_BOTTOM high-level signal of the load switch U1 is transmitted to the ENN terminal of the load switch U2 through the Schottky diode D1, making the ENN terminal of the load switch U2 high level, causing the IN terminal and OUT terminal of the load switch U2 to be disconnected. Even if the BACK_POGO-PIN interface (charging interface I2) is connected to the power adapter at this time, the load switch U2 cannot charge the battery.

[0046] Similarly, the RXN_BOTTOM high-level signal of the load switch U1 is transmitted to the ENN terminal of the load switch U3 through the Schottky diode D3, making the ENN terminal of the load switch U3 high level, causing the IN terminal and OUT terminal of the load switch U3 to be disconnected. Even if the TYPE-C interface (charging interface I3) is connected to the USB power adapter at this time, the load switch U3 cannot charge the battery.

[0047] Therefore, the BOTTOM_POGO-PIN interface (charging interface I1) has the highest charging priority. When the BOTTOM_POGO-PIN interface is charging, the power of other interfaces cannot charge the battery.

[0048] Scenario 2: The BOTTOM_POGO-PIN interface (charging interface I1) is left floating, and the BACK_POGO-PIN interface (charging interface I2) is connected to a power adapter.

[0049] When the BOTTOM_POGO-PIN interface (charging interface I1) is suspended and the BACK_POGO-PIN interface (charging interface I2) is connected to the power adapter, the ENN terminal of the load switch U1 is at a low level, RXN_BOTTOM is at a low level, and the ENN terminal of the load switch U2 is also at a low level under the action of the pull-down resistor R2. The RXN terminal signal RXN_BACK of the load switch U2 is flipped to a high level, the VSYS terminal signal BACK_SNS is at a high level, and is transmitted to the GPIO port of the microprocessor 300. The system generates a charging response, and the OUT terminal signal VBUS_IN of the load switch U2 is 5V, and the power supply 5V is transmitted to the charging chip 100 to charge the battery 200.

[0050] At the same time, the RXN_BACK high-level signal of the load switch U2 is transmitted to the ENN terminal of the load switch U3 through the Schottky diode D2, so that the ENN terminal of the load switch U3 is at a high level, causing the IN terminal and the OUT terminal of the load switch U3 to be disconnected. Even if the TYPE-C interface is connected to a USB power adapter at this time, the load switch U3 cannot charge the battery.

[0051] Therefore, the BACK_POGO-PIN interface (charging interface I2) has the second highest charging priority. When the BACK_POGO-PIN interface is charging, the power supply of the TYPE-C interface cannot charge the battery.

[0052] Scenario 3: The BOTTOM_POGO-PIN interface (charging interface I1) and the BACK_POGO-PIN interface (charging interface I2) are both suspended, and the TYPE-C interface (charging interface I3) is connected to a USB power adapter.

[0053] When the BOTTOM_POGO-PIN interface (charging interface I1) and the BACK_POGO-PIN interface (charging interface I2) are both suspended, and the TYPE-C interface (charging interface I3) is connected to the USB power adapter, the ENN terminals of the load switches U1 and U2 are both at a low level, and RXN_BOTTOM is also at a low level. At this time, the ENN terminal of the load switch U3 is at a low level under the action of the pull-down resistor R3, and the VSYS terminal signal VBUS_SNS is at a high level and is transmitted to the GPIO port of the microprocessor 300. The system generates a charging response, and the OUT terminal signal VBUS_IN of the load switch U3 is 5V, and the power supply 5V is transmitted to the charging chip 100 to charge the battery 200.

[0054] In some embodiments, see Figure 3 and Figure 4 As shown, it also includes a power module 400 connected to the battery 200, and the power module 400 is used to output voltage to power external devices;

[0055] Each charging interface I1-3 has a detection terminal OTG_DET1-3, and the microprocessor 300 has an enable terminal OTG_EN1-3 that responds to an interrupt signal from the detection terminal OTG_DET1-3;

[0056] When any charging interface I1-3 is connected to an external device, the corresponding detection terminal OTG_DET1-3 generates an interrupt signal, and the microprocessor 300 receives the interrupt signal and performs an interrupt response to pull the level of the corresponding enable terminal OTG_EN1-3 high;

[0057] When the level of any one or more enable terminals OTG_EN1-3 is pulled high, the microprocessor 300 controls the power module 400 to turn on, and the output voltage supplies power to the external device. In this embodiment, OTG_DET1 corresponds to OTG_EN1, OTG_DET2 corresponds to OTG_EN2, OTG_DET3 corresponds to OTG_EN3, and the model of the power module 400 is ETA1090A.

[0058] In specific implementation, in different scenarios, the mobile terminal can mount external devices through different interfaces, that is, the mobile terminal provided by this embodiment works in OTG mode without affecting multi-path charging, which means that the mobile terminal can mount external devices through different interfaces, such as USB flash drives, mice, mobile phones, handheld PDAs, etc. In OTG mode, the mobile phone can power external devices or perform data communications to meet the needs of various usage scenarios.

[0059] In this embodiment, see Figure 3 and Figure 4As shown, a current limiting chip U11-13 for limiting current and an overvoltage protection chip U21-23 for limiting voltage are also connected in series between the power module 400 and the charging interface I1-3. The model of the current limiting chip U11-13 is SGM2593; the model of the overvoltage protection chip U21-23 is SGM40666; the EN pins of the current limiting chip U11, the current limiting chip U12, and the current limiting chip U13 are connected to OTG_EN1, OTG_EN2, and OTG_EN3 respectively.

[0060] Specifically, the pull-down resistor value of each current limiting chip U11-13 is 4.7K, which is used to set the overcurrent protection threshold IL IMIT In this embodiment, the 4.7K pull-down resistor sets the IL IMIT is 1.5A, that is, when the current flowing through the current limiting chip U11, the current limiting chip U12, and the current limiting chip U13 is greater than 1.5A, the current limiting chip starts the protection mechanism and disconnects the internal connection to protect the subsequent circuit; and the ADI pin of the overvoltage protection chip U21-23 is used for resistor voltage division to set the overvoltage protection threshold V OVP In this embodiment, V is determined by setting a 48K voltage divider resistor and a 12K voltage divider resistor. OVP =6V, that is, when the VIN of the overvoltage protection chip U21, the overvoltage protection chip U22, and the overvoltage protection chip U23 is 6V, the overvoltage protection chip will cut off the path between VIN and VOUT to protect the subsequent circuit from damage by high voltage.

[0061] When working, illustratively:

[0062] When an external device is mounted on the BOTTOM_POGO_PIN interface and used as an OTG device, the BOTTOM_OTG_DET signal of the BOTTOM_POGO_PIN interface is short-circuited with GND. At this time, the microprocessor 300 receives an interrupt signal and responds to an interrupt, i.e., the enable terminal OTG_EN1 is pulled high, and then the enable signals of the current limiting chip U11, the current limiting chip U12, and the current limiting chip U13 are pulled high, so that the DCDC chip (power module 400) works and outputs OUT_5V=5V voltage. The current limiting chip U11 is turned on, the overvoltage protection chip U21 is turned on, and finally the 5V voltage is passed to the BOTTOM_OUTPUT signal to power the external device. The data of the external device is transmitted through the DP signal and the DM signal.

[0063] Similarly, when an external device is mounted on the BCAK_POGO_PIN interface, the power module 400 is turned on, the current limiting chip U12 is turned on, and the overvoltage protection chip U22 is turned on, and finally the 5V voltage is passed to the BACK_OUTPUT signal to power the external device. The data of the external device is transmitted through the DP signal and DM signal.

[0064] Similarly, when an external device is mounted on the TYPE_C interface, the power module 400 is turned on, the current limiting chip U13 is turned on, and the overvoltage protection chip U23 is turned on, and finally the 5V voltage is passed to the TYPE_C_VBUS signal to power the external device. The data of the external device is transmitted through the DP signal and DM signal.

[0065] Another aspect of this embodiment provides a mobile terminal, including the multi-path charging circuit described in the above scheme. For the convenience and simplicity of description, those skilled in the art can clearly understand that the specific working process of the system described above can refer to the corresponding process in the above multi-path charging circuit embodiment, and will not be repeated here.

[0066] The multi-path charging circuit and mobile terminal provided in this embodiment can quickly respond to power requirements in different scenarios through complete and rich power switching logic, and have wide applicability, and are suitable for any electronic products that require multi-path charging and OTG switching functions. In addition, this solution effectively solves the problems of leakage, backflow, logical judgment errors, etc. in the multi-path charging and OTG switching process in the prior art, improves the power management efficiency and safety of electronic equipment, is suitable for large-scale mass production, and can meet the market demand for high-quality electronic products.

[0067] In the description of the present invention, it should be noted that the terms "vertical", "up", "down", "horizontal", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0068] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0069] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A multi-path charging circuit, characterized in that: include: Multiple charging interfaces (I1-3) for receiving charging input from different power adapters; A plurality of load switches (U1-3), wherein an IN terminal of the load switch (U1-3) is connected to a charging interface (I1-3); A charging chip is connected to the OUT terminal of the load switch (U1-3) and is used to receive a charging current from the OUT terminal of the load switch (U1-3) to charge the battery; A microprocessor, wherein a GPIO port of the microprocessor is connected to a VSYS terminal of the load switch (U1-3) for receiving a charging status signal from the load switch (U1-3); Multiple Schottky diodes (D1-3); Wherein, the ENN terminal of the load switch U1 is grounded through the resistor R1, the ENN terminal of the load switch U2 is grounded through the resistor R2, and the ENN terminal of the load switch U3 is grounded through the resistor R3; The RXN terminal of the load switch U1 is divided into two paths, one of which is connected to the positive electrode of the Schottky diode D1, and the other is connected to the positive electrode of the Schottky diode D3; the cathode of the Schottky diode D1 is connected to the connection node between the load switch U2 and the resistor R2, and the cathode of the Schottky diode D3 is connected to the connection node between the load switch U3 and the resistor R3; The RXN terminal of the load switch U2 is connected to the anode of the Schottky diode D2, and the cathode of the Schottky diode D2 is connected to the connection node between the load switch U3 and the resistor R3.

2. The multi-path charging circuit according to claim 1, characterized in that: The resistance values ​​of the resistors R1, R2 and R3 are all 4.7K.

3. The multi-path charging circuit according to claim 1, characterized in that: The model of the load switch (U1-3) is AW32102.

4. The multi-path charging circuit according to claim 1, 2 or 3, characterized in that: Also included is a power module connected to the battery, the power module is used to output voltage to power external devices; Each charging interface (I1-3) has a detection terminal (OTG_DET1-3), and the microprocessor has an enable terminal (OTG_EN1-3) that responds to an interrupt signal of the detection terminal (OTG_DET1-3); When any charging interface (I1-3) is connected to an external device, the corresponding detection terminal (OTG_DET1-3) generates an interrupt signal, and the microprocessor receives the interrupt signal and performs an interrupt response to pull the level of the corresponding enable terminal (OTG_EN1-3) high; When the level of any one or more enable terminals (OTG_EN1-3) is pulled high, the microprocessor controls the power module to turn on, and the output voltage supplies power to the external device.

5. The multi-path charging circuit according to claim 4, characterized in that: A current limiting chip (U11-13) for limiting current and an overvoltage protection chip (U21-23) for limiting voltage are also connected in series between the power module and the charging interface (I1-3).

6. The multi-path charging circuit according to claim 5, characterized in that: The model of the current limiting chip (U11-13) is SGM2593, and the model of the overvoltage protection chip (U21-23) is SGM40666.

7. The multi-path charging circuit according to claim 4, characterized in that: The model of the power module is ETA1090A.

8. A mobile terminal, characterized in that: The invention comprises the multi-path charging circuit and the mobile terminal according to any one of claims 1 to 7.

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