Charging control circuit of intelligent display screen equipment and electrical equipment

Abstract

The invention discloses a charging control circuit of intelligent display screen equipment, which relates to the field of charging and comprises a capacitor, a first resistor and a second resistor. The capacitor is used for being connected with a VBUS which transmits a power supply signal after an adapter is inserted, the first resistor and the second resistor are connected with the capacitor in series, the first resistor and the second resistor are connected in parallel relative to a VDC pin, and the first resistor and the second resistor divide the voltage to enable the voltage detected by the detection pin VDC to be within the VDC voltage control range of the PMIC. When the adapter is inserted into the intelligent display screen equipment, the capacitor is charged, the capacitor is fully charged to disconnect the circuit after the VDC detects an instant high level, and the pin VDC does not detect the high level any more, so that the problem that the intelligent display screen equipment is not awakened or repeatedly awakened after shutdown under the condition that the intelligent display screen equipment is connected with the adapter is solved. Meanwhile, the circuit provided by the invention is simple in structure, reliable in operation, low in cost and convenient to popularize.

Description

Technical Field

[0001] The present invention relates to the field of charging, and in particular to a charging control circuit and electrical equipment of a smart display device. Background Art

[0002] A smart display device with a battery is an electronic device that integrates a battery and a smart display. A smart display device usually refers to a display device with smart functions. It combines the high-definition display function of a traditional display and the portability of a mobile device after being equipped with a battery, and has demonstrated its unique application value in many fields. However, as long as the smart display device is plugged in with an adapter, the detection pin of the internal power management integrated circuit (Power Management IC, PMIC for short) connected to the adapter will always be in a high-level state. When the detection pin is in a high-level state, the PMIC will automatically power the smart display device. Since the detection pin connected to the adapter is always in a high-level state, when the smart display device detects that the battery is fully charged and shuts down the software, the PMIC will turn on the smart display device again. When the smart display device detects that the battery is fully charged and shuts down again, it will fall into a shutdown and startup cycle problem, causing hidden dangers in the entire power supply system.

[0003] At present, in order to solve the above problems, the common practice is to implant a microcontroller unit (MCU) into the above devices to control the devices. However, the cost of implanting an MCU to prevent the smart display device from repeatedly turning on and off is high. At the same time, when some pins of the MCU are in a dormant state, it is difficult to wake up the smart display device for normal charging, which poses certain safety risks.

[0004] Therefore, there is an urgent need for a reliable charging solution to solve the problem of failure to wake up the smart display device and repeated wake-up after shutting down when the smart display device with a battery is connected to a device adapter. Summary of the invention

[0005] In view of this, the purpose of the present invention is to provide a charging control circuit and electrical equipment for a smart display device, which effectively solves the problem that the smart display device with a current battery is repeatedly awakened after being shut down when connected to a device adapter. The specific scheme is as follows:

[0006] In a first aspect, the present application provides a charging control circuit for a smart display device, comprising: a capacitor, a first resistor, and a second resistor;

[0007] The first end of the capacitor is connected to the positive electrode of VBUS, and the second end of the capacitor is connected to the first end of the first resistor;

[0008] The second end of the first resistor is connected to the first end of the second resistor, and a common end of the first resistor and the second resistor is connected to a detection pin of the PMIC;

[0009] The second end of the second resistor is connected to the negative electrode of VBUS, and the VBUS is a voltage supply connected to a power adapter.

[0010] Optionally, it also includes: a diode;

[0011] An anode of the diode is connected to the second end of the capacitor, and a cathode of the diode is connected to the first end of the first resistor.

[0012] Optionally, it also includes: a low power consumption circuit;

[0013] The low power consumption circuit comprises: a first switch tube, a second switch tube and a third resistor;

[0014] The first end of the first switch tube and the control end of the second switch tube are connected to the positive electrode of the VBUS;

[0015] The control end of the first switch tube is connected to the control signal end; wherein the control signal end is powered off when the smart display device is turned off;

[0016] The first end of the second switch tube is connected to the first end of the third resistor;

[0017] The second end of the third resistor is connected to the Vset pin.

[0018] Optionally, the first switch tube is an NMOS transistor;

[0019] The gate of the NMOS transistor is the control end of the first switch tube, the source of the NMOS transistor is the second end of the first switch tube, and the drain of the NMOS transistor is the first end of the first switch tube.

[0020] Optionally, the second switch tube is an NMOS tube;

[0021] The gate of the NMOS transistor is the control terminal of the second switch tube, the source of the NMOS transistor is the second terminal of the second switch tube, and the drain of the NMOS transistor is the first terminal of the second switch tube.

[0022] Optionally, the low power consumption circuit further includes: a fourth resistor and a fifth resistor;

[0023] The first end of the fourth resistor is connected to the control signal end;

[0024] The second end of the fourth resistor is connected to the control end of the first switch tube;

[0025] A first end of the fifth resistor is connected to the positive electrode of the VBUS, and a second end of the fifth resistor is connected to the first end of the first switch tube.

[0026] Optionally, the low power consumption circuit further includes: a sixth resistor;

[0027] The first end of the sixth resistor is connected to the control end of the first switch tube;

[0028] Optionally, the low power consumption circuit further includes: a seventh resistor;

[0029] The first end of the seventh resistor is connected to the first end of the first switch tube;

[0030] The second end of the seventh resistor is connected to the control end of the second switch tube.

[0031] Optionally, the low power consumption circuit further includes: an eighth resistor;

[0032] The first end of the eighth resistor is connected to the control end of the second switch tube;

[0033] The second end of the eighth resistor is connected to the second end of the second switch tube, and the common end is grounded.

[0034] In a second aspect, the present application provides an electrical device, including a charging control circuit of the smart display device.

[0035] A charging control circuit for a smart display screen device provided in the present application is composed of a capacitor, a first resistor, and a second resistor. The capacitor is connected to VBUS, which serves to disconnect the loop after the device is shut down. The detection pin VDC of the PMIC is connected in series with the capacitor, and is in a low-level state after the capacitor is disconnected, so the device can be shut down without being awakened when the adapter is connected. The voltage division of the first resistor and the second resistor makes the voltage detected by VDC within the VDC voltage control range of the PMIC. Therefore, the present application effectively solves the problem that the smart display screen device cannot be awakened 100% and repeatedly awakened after being shut down when the smart display screen device is connected to an adapter. At the same time, the circuit structure provided in the present application is simple, reliable in operation, low in cost, and easy to promote. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0037] Figure 1A charging control circuit diagram of a smart display device provided in an embodiment of the present application;

[0038] Figure 2 A timing diagram of a charging control circuit of a smart display device provided in an embodiment of the present application;

[0039] Figure 3 A low-power charging circuit diagram of a smart display device provided in an embodiment of the present application;

[0040] Figure 4 A timing diagram of a low-power charging circuit of a smart display device provided in an embodiment of the present application;

[0041] Figure 5 A charging control circuit flow chart of a smart display device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0042] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] The core of this application is to provide a charging control circuit and electrical equipment for a smart display screen device.

[0044] In order to enable those skilled in the art to better understand the present application, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0045] At present, when a smart display screen device is connected to an adapter, the pin of the internal PMIC connected to the adapter will always be in a high-level state. In this high-level state, the PMIC will automatically power the smart display screen device. Since the detection pin connected to the adapter is always in a high-level state, when the smart display screen device detects that the battery is fully charged and performs a software shutdown, the PMIC will turn the smart display screen device on again. When the smart display screen device detects that the battery is fully charged and shuts down again, it will fall into a shutdown and startup cycle, causing hidden dangers in the entire power supply system. In order to solve the above problems, a common practice is to implant an MCU into the above-mentioned devices to control the devices. However, the cost of implanting an MCU to prevent the smart display screen device from repeatedly turning on and off is high, and there is a situation where some of the MCU pins are in a dormant state and are difficult to wake up. For this reason, there is an urgent need for a reliable charging solution to solve the problem of smart display screen devices with batteries being repeatedly awakened after being shut down when connected to an adapter.

[0046] Figure 1A charging control circuit diagram of a smart display screen device provided in an embodiment of the present application. As shown in the figure, in order to solve the above problem, this embodiment provides a charging control circuit of a smart display screen device, including: a capacitor C1, a first resistor R1 and a second resistor R2;

[0047] A first end of the capacitor C1 is connected to the positive electrode of VBUS, and a second end of the capacitor C1 is connected to a first end of the first resistor R1;

[0048] The second end of the first resistor R1 is connected to the first end of the second resistor R2, and the common end of the first resistor R1 and the second resistor R2 is connected to the detection pin of the PMIC;

[0049] The second end of the second resistor R2 is connected to the negative electrode of VBUS, and VBUS is a voltage supply connected to a power adapter.

[0050] In the charging control circuit of the smart display device, if the capacitor C1 is not added in the shutdown state, after the adapter is inserted, the switch S1 is closed, the high level is detected at point C, and the VDC pin transmits the high level signal to the PMIC, and the PMIC automatically turns on to power the main control chip. When the power-off adapter is inserted, the smart display device will continue to charge until the smart display device is fully charged and completely shut down. At this time, as long as the adapter is connected, the VDC pin is still at a high level, and the PMIC will turn on again, causing the device to enter a repeated power-on and power-off cycle. This will not only cause the screen of the smart display device to light up in a cycle, affecting the user experience, but will also damage the battery of the smart display device and affect the battery life.

[0051] When capacitor C1 is connected in series to the circuit and the adapter is plugged into the smart display device, switch S1 is closed. At this time, VBUS charges capacitor C1. At the moment of closing, the path is equivalent to being turned on. Point C detects a high level, and the VDC pin transmits the high level signal to PMIC. PMIC automatically turns on to supply power to the main control chip. Since capacitor C1 is a capacitor with a very small capacitance, it can be quickly fully charged after the switch is closed. Due to the basic characteristics of the capacitor, after capacitor C1 is fully charged, Figure 1 The circuit is equivalent to being disconnected, and point C changes from a high level to a low level. Since the state of the VDC pin no longer affects the operation of the system after the PMIC system is turned on, the smart display device will no longer be awakened after being fully charged and turned off. At this time, the VDC pin is at a low level, and the PMIC will no longer automatically turn on to power the main control chip. It is understandable that Figure 1 The switch S1 in the circuit diagram is closed when the adapter is inserted. The switch S1 here is not a real switch device, but for the convenience of understanding, the adapter insertion action is abstracted as VBUS starting to supply power and switch S1 turning on.

[0052] Figure 2 This is a timing diagram of a charging control circuit of a smart display device provided in an embodiment of the present application. Figure 1 The timing diagram corresponding to the circuit shown is as follows: Figure 2 As shown, from t1 to t2, VBUS is suspended and defaults to 5V. From t1 to t2, the adapter is inserted, switch S1 is closed, and the capacitor is quickly charged to the VBUS voltage. In actual use, due to the resistance of electronic components and wires, there is power loss, so the VBUS voltage cannot be fully reached. Before the system is actually turned on, the smart display device enters the screen-off charging state, the first switch tube is turned on, and the system of the smart display device is in a 20V power supply to charge the smart display device. When the adapter is unplugged at t6, the capacitor is discharged, and a reverse voltage appears in the timing diagram. Due to the presence of the diode, the reverse voltage will not affect the PMIC.

[0053] It can be seen that a charging control circuit of a smart display screen device provided in an embodiment of the present application is composed of a capacitor, a first resistor, and a second resistor. The capacitor is connected to VBUS, which plays a role in disconnecting the loop after the device is shut down. The detection pin VDC of the PMIC is connected in series with the capacitor, and is in a low-level state after the capacitor is disconnected, so the device can be shut down without being awakened when the adapter is connected. The voltage division of the first resistor and the second resistor makes the voltage detected by VDC within the VDC voltage control range of the PMIC. Therefore, the present application effectively solves the problem of being repeatedly awakened after shutting down when the smart display screen device is connected to the adapter. At the same time, the circuit structure provided in the present application is simple, reliable in operation, low in cost, and easy to promote.

[0054] According to the above embodiment, this embodiment provides a specific solution, further comprising: a diode D1;

[0055] The anode of the diode is connected to the second end of the capacitor C1 , and the cathode of the diode D1 is connected to the first end of the first resistor R1 .

[0056] like Figure 1 A charging control circuit diagram of a smart display device is provided. During the charging and discharging process of capacitor C1, capacitor C1 converts electrical energy into electric field energy for storage. When capacitor C1 is charged, the electric field energy gradually accumulates inside the capacitor; when the voltage across capacitor C1 reaches a value close to the power supply voltage, the charge between the plates tends to stabilize to Q, and the capacitance C remains unchanged. According to the voltage U=Q / C, when the adapter is disconnected, VBUS is at a low level, and capacitor C1 begins to discharge at voltage U. During the discharge process, the charge flows from the negative plate of the capacitor through the conductor and the medium to the positive plate, so that the negative plate of the capacitor carries a positive charge and the positive plate carries a negative charge, which will generate a reverse voltage. At this time, point b is negative. If the component diode D1 is not added, the negative pressure will have an impact on point C. From the perspective of equipment safety, adding a diode D1 between capacitor C1 and the first resistor R1 can effectively reduce the impact of the negative pressure at point b on point C.

[0057] It can be seen that the solution provided in the embodiment of the present application can cope with the situation where the adapter is unplugged. After the adapter is unplugged and the capacitor is discharged, due to the unidirectional conductivity of the diode, the current cannot flow backwards, thereby reducing the impact of the negative pressure at point b on point C.

[0058] According to the above embodiment, this embodiment provides a specific solution, further comprising: a low power consumption circuit;

[0059] The low power consumption circuit includes: a first switch tube T1, a second switch tube T2 and a third resistor R3;

[0060] The first end of the first switch tube T1 and the control end of the second switch tube T2 are connected to the positive electrode of VBUS;

[0061] The control end of the first switch tube T1 is connected to the control signal end; wherein the control signal end is powered off when the smart display device is turned off;

[0062] A first end of the second switch tube T2 is connected to a first end of the third resistor R3;

[0063] The second end of the third resistor R3 is connected to the Vset pin.

[0064] Figure 3 A low-power charging circuit diagram of a smart display device provided in an embodiment of the present application, such as Figure 3 As shown, Vin is the internal voltage input of the smart display device. When the smart display device is turned on, Vin inputs a stable voltage value. When the smart display device software is shut down, Vin has no input. When the smart display device is turned on, the Vin input at point D is connected to the control end of the first switch tube T1, the first switch tube T1 is turned on, VBUS is grounded, and the voltage at point F is the ground voltage connected to the second switch tube T2, and the second switch tube T2 is not turned on. At this time, the smart display device is connected to a 20V input voltage for charging. When the smart display device is fully charged in the shutdown state, the smart display device starts the software shutdown. At this time, Vin has no input, the first switch tube T1 is not turned on, and point F is connected to the VBUS input and the control end of the second switch tube T2. At this time, the second switch tube T2 is turned on. Vset is pulled down by the third resistor R3 and configured to the 12V position of the PD sink IC to power the system.

[0065] Figure 4 This is a timing diagram of a charging control circuit of a smart display device provided in an embodiment of the present application. Figure 3 The timing diagram corresponding to the circuit shown is as follows: Figure 4As shown, the adapter provides voltage through VBUS. When no adapter is inserted, the default voltage is 5V. When the smart display device is turned off and the adapter is connected, before the system is turned on, the smart display device is configured with a voltage of 12V. When the smart display device is turned on, the smart display device is configured with a voltage of 20V. When the smart display device is turned on, the control signal end will stabilize at a specific voltage value.

[0066] It can be seen that the embodiment of the present application provides a low-power circuit. After the smart display screen device is fully charged and shut down by software, the adapter's power supply to the smart display screen device is configured to 12V by the Vset pull-down resistor, and the shutdown power is greatly reduced, thereby achieving low power consumption of the smart display screen device as a whole.

[0067] According to the above embodiment, this embodiment provides a specific solution, including: the first switch tube T1 is an NMOS transistor;

[0068] The gate of the NMOS transistor is the control terminal of the first switch tube T1 , the source of the NMOS transistor is the second terminal of the first switch tube T1 , and the drain of the NMOS transistor is the first terminal of the first switch tube T1 .

[0069] In this embodiment, when Vin has a voltage input, the control terminal of the first switch tube T1, that is, the gate voltage is greater than the source ground voltage, and the first switch tube T1 is turned on.

[0070] According to the above embodiment, this embodiment provides a specific solution, including: the second switch tube T2 is an NMOS tube;

[0071] The gate of the NMOS transistor is the control terminal of the second switch tube T2 , the source of the NMOS transistor is the second terminal of the second switch tube T2 , and the drain of the NMOS transistor is the first terminal of the second switch tube T2 .

[0072] In this embodiment, when Vin has voltage input, the first switch tube T1 is turned on, and point F is connected to the gate of the second switch tube T2 and grounded. At this time, the gate voltage of the second switch tube T2 is not greater than the source of the second switch tube T2, the second switch tube T2 is turned off, Vset is suspended, and VBUS is 20V. When the smart display device software is shut down, Vin has no input, the first switch tube T1 is not turned on, point F is connected to the VBUS input and the gate of the second switch tube T2, at this time, the gate voltage of the second switch tube T2 is greater than the source voltage, the second switch tube T2 is turned on, Vset is grounded through the third resistor, and VBUS is 12V.

[0073] In the embodiment of the present application, the second switch tube T2 uses an NMOS tube to help the charging control circuit effectively control the voltage conversion, so that the overall power consumption of the smart display device is reduced when it is turned off. During actual operation, the NMOS tube can be replaced with other switch tube models, which is not limited here.

[0074] According to the above embodiment, this embodiment provides a specific solution, further comprising: a fourth resistor R4 and a fifth resistor R5;

[0075] A first end of the fourth resistor R4 is connected to the control signal end Vin;

[0076] The second end of the fourth resistor R4 is connected to the control end of the first switch tube T1;

[0077] A first end of the fifth resistor R5 is connected to the positive electrode of VBUS, and a second end of the fifth resistor R5 is connected to the first end of the first switch tube T1.

[0078] like Figure 3 As shown, in this embodiment, the fourth resistor R4 is connected to the gate of the first switch tube T1. It can be seen from the above embodiment that Vin is used as the conduction voltage of the first switch tube T1. The fourth resistor R4 is connected between Vin and the control end of the first switch tube T1 to limit the rate of gate charging and discharging, and prevent the gate voltage from generating noise due to rapid changes. The fifth resistor R5 serves as a pull-up resistor for the drain of the first switch tube T1, providing a default level state for the drain, while limiting the current flowing through the first switch tube T1 to prevent the first switch tube T1 from being damaged due to excessive current. It should be noted that when the smart display screen is turned off, the adapter is inserted for charging. The smart display screen device first enters the power display interface to detect the charging status, and enters the screen-off charging state after a period of time. At this time, Vin has a voltage input, and the smart display screen device adapter input is configured to charge at 20V; when the smart display screen device is plugged in the adapter when it is turned on, the smart display screen device is manually turned off, and Vin has no voltage input. At this time, the smart display screen device adapter input is configured to charge at 12V.

[0079] According to the above embodiment, this embodiment provides a specific solution, further comprising: a sixth resistor;

[0080] A first end of the sixth resistor is connected to the control end of the first switch tube T1 , a second end of the sixth resistor R6 is connected to the second end of the first switch tube T1 , and a common end is grounded.

[0081] In this embodiment, the sixth resistor R6 and the fourth resistor R4 can play a role of voltage division, so that the control pin of the first switch tube T1 is not damaged due to excessive voltage shock.

[0082] According to the above embodiment, this embodiment provides a specific solution, the low power consumption circuit further includes: a seventh resistor;

[0083] A first end of the seventh resistor R7 is connected to a first end of the first switch tube;

[0084] The second end of the seventh resistor R7 is connected to the control end of the second switch tube T2.

[0085] According to the above embodiment, this embodiment provides a specific solution, the low power consumption circuit further includes: an eighth resistor R8;

[0086] A first end of the eighth resistor R8 is connected to the control end of the second switch tube T2;

[0087] The second end of the eighth resistor R8 is connected to the second end of the second switch tube T2, and the common end is grounded.

[0088] In this embodiment, the seventh resistor R7 and the eighth resistor R8 play a role of voltage division, so that the control pin of the second switch tube T2 is not damaged due to excessive voltage shock.

[0089] The technical solution in this application can adapt to different charging states according to different states of the smart display device. Figure 5 As shown in the figure, when the smart display device is in the off state and the adapter is inserted, as shown on the left side of the flowchart, after the adapter is inserted, the basic hardware of the smart display device is turned on. At this time, the system is not fully turned on, and the power display interface is entered to detect the charging status. After a period of time, it enters the screen-off charging state. In this state, the VDC detection pin detects a high level and runs Figure 1 As shown in the circuit 1, the PMIC starts to power the system. Figure 3 Circuit 2 configures the smart display device adapter input to 20V, and the smart display device enters the 20V charging state. When the battery is fully charged, the system automatically shuts down. At this time, the smart display device passes Figure 3 Circuit 2 configures the smart display device adapter input to 12V. At this time, the smart display device can achieve power consumption of less than or equal to 0.5W after shutdown. When the smart display device is powered on and the adapter is inserted, Figure 5 As shown on the right, VDC runs after detecting a high level Figure 1 In the circuit 1 shown, the smart display device adapter input is configured to 20V, and the smart display device enters the 20V charging state when it is turned on. After the smart display device is fully charged, the user can shut down the smart display device through software. Figure 3 Circuit 2 configures the smart display device adapter input to 12V. When the battery is fully charged, the power consumption of the smart display device is less than or equal to 0.5W after the system is shut down. The above are all power consumptions tested when the adapter is plugged in.

[0090] The above is a detailed introduction to the charging control circuit and electrical equipment of a smart display device provided by the present application. The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the embodiments can refer to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part description. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present application, several improvements and modifications can be made to the present application, and these improvements and modifications also fall within the scope of protection of the claims of the present application.

[0091] It should also be noted that, in this specification, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

Claims

1. A charging control circuit for a smart display device, characterized in that: include: A capacitor, a first resistor, and a second resistor; The first end of the capacitor is connected to the positive electrode of VBUS, and the second end of the capacitor is connected to the first end of the first resistor; The second end of the first resistor is connected to the first end of the second resistor, and a common end of the first resistor and the second resistor is connected to a detection pin of the PMIC; The second end of the second resistor is connected to the negative electrode of VBUS, and the VBUS is a voltage supply connected to a power adapter.

2. The charging control circuit of the smart display device according to claim 1, characterized in that: Also includes: diode; An anode of the diode is connected to the second end of the capacitor, and a cathode of the diode is connected to the first end of the first resistor.

3. The charging control circuit of the smart display device according to claim 1 or 2, characterized in that: Also includes: Low power circuit; The low power consumption circuit comprises: a first switch tube, a second switch tube and a third resistor; The first end of the first switch tube and the control end of the second switch tube are connected to the positive electrode of the VBUS; The control end of the first switch tube is connected to the control signal end; wherein the control signal end is powered off when the smart display device is turned off; The first end of the second switch tube is connected to the first end of the third resistor; The second end of the third resistor is connected to the Vset pin.

4. The charging control circuit of the smart display device according to claim 3, characterized in that: The first switch tube is an NMOS transistor; The gate of the NMOS transistor is the control end of the first switch tube, the source of the NMOS transistor is the second end of the first switch tube, and the drain of the NMOS transistor is the first end of the first switch tube.

5. The charging control circuit of the smart display device according to claim 3, characterized in that: The second switch tube is an NMOS tube; The gate of the NMOS transistor is the control terminal of the second switch tube, the source of the NMOS transistor is the second terminal of the second switch tube, and the drain of the NMOS transistor is the first terminal of the second switch tube.

6. The charging control circuit of the smart display device according to claim 4, characterized in that: The low power consumption circuit further includes: a fourth resistor and a fifth resistor; The first end of the fourth resistor is connected to the control signal end; The second end of the fourth resistor is connected to the control end of the first switch tube; A first end of the fifth resistor is connected to the positive electrode of the VBUS, and a second end of the fifth resistor is connected to the first end of the first switch tube.

7. The charging control circuit of the smart display device according to claim 4, characterized in that: The low power consumption circuit further includes: a sixth resistor; A first end of the sixth resistor is connected to the control end of the first switch tube, a second end of the sixth resistor is connected to the second end of the first switch tube, and a common end is grounded.

8. The charging control circuit of the smart display device according to claim 5, characterized in that: The low power consumption circuit further includes: a seventh resistor; The first end of the seventh resistor is connected to the first end of the first switch tube; The second end of the seventh resistor is connected to the control end of the second switch tube.

9. The charging control circuit of the smart display device according to claim 5, characterized in that: The low power consumption circuit further includes: an eighth resistor; The first end of the eighth resistor is connected to the control end of the second switch tube; The second end of the eighth resistor is connected to the second end of the second switch tube, and the common end is grounded.

10. An electrical device, characterized in that: A charging control circuit comprising the smart display device as described in any one of claims 1 to 9.

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