Anti-overcharging hot plug charging circuit and charging device

Abstract

The utility model discloses an anti-overcharge hot plug charging circuit and a charging device, comprising a power supply voltage regulation module, a charging switch module, a sampling comparison module, a current sampling module and a control module, the input end of the power supply voltage regulation module is used for being connected with a power supply, and the output end of the power supply voltage regulation module is connected with the head end of the charging switch module; the tail end of the charging switch module is connected with the charging connecting plug, the sampling comparison module comprises a comparison unit and a reference unit, the first input end of the comparison unit is connected with the tail end of the charging switch module, the reference unit is used for providing reference voltage, and the second input end of the comparison unit is connected with the reference unit; the sampling end of the current sampling module is connected with the head end of the charging switch module, the control module is connected with the output end of the current sampling module, the output end of the comparison unit and the controlled end of the charging switch module, and the design is accurate in detection, automatic in charging operation and safe and reliable in use.

Description

Technical Field

[0001] The utility model relates to the technical field of charging equipment, and in particular to an overcharging prevention hot-swap charging circuit and a charging device. Background Art

[0002] Charging equipment is used in all walks of life. Users can use the charging connector in the charging equipment to plug in the charging load, and then charge the charging load. In the past, the charging equipment could not know whether the charging load is connected to the charging connector or whether the charging load is fully charged. Therefore, the charging connector remains charged for a long time. However, when the charging load is fully charged or the charging connector and the charging load become loose and fall off, it is easy to cause overcharging and the risk of electric shock, and the safety level is low.

[0003] Therefore, some manufacturers will set up hot plug detection circuits in charging equipment, but the sensitivity is relatively low and the response is inaccurate. Utility Model Content

[0004] The utility model aims to solve at least one of the technical problems existing in the prior art. To this end, the utility model provides an overcharge prevention hot-swap charging circuit and a charging device, which have accurate detection, automatic charging operation, and are safe and reliable to use.

[0005] According to the first aspect of the utility model, an overcharge prevention hot-swap charging circuit includes: a power supply voltage regulating module, the input end of the power supply voltage regulating module is used to connect to the power supply, and the power supply voltage regulating module is used to modulate the output voltage of the power supply into a charging voltage; a charging switch module, the output end of the power supply voltage regulating module is connected to the head end of the charging switch module, and the tail end of the charging switch module is connected to the charging plug connector, and the charging plug connector is used to connect to the charging load; a sampling and comparison module, including a comparison unit and a reference unit, the first input end of the comparison unit is connected to the tail end of the charging switch module, the reference unit is used to provide a reference voltage, and the second input end of the comparison unit is connected to the reference unit; a current sampling module, the sampling end of the current sampling module is connected to the head end of the charging switch module; a control module, respectively connected to the output end of the current sampling module, the output end of the comparison unit and the controlled end of the charging switch module.

[0006] According to an overcharge prevention hot-swap charging circuit of an embodiment of the utility model, at least the following beneficial effects are achieved:

[0007] In the utility model, before the charging load is connected to the charging plug connector, the first input end of the comparison unit obtains the load connection voltage at the charging plug connector. Since there is no charging load connected, the control module can learn the comparison between the load connection voltage and the reference voltage provided by the reference unit from the signal output by the comparison unit, and learn that there is no charging load connected, the charging switch module remains turned off, and there is no charging voltage input to the charging plug connector. When the charging load is connected to the charging plug connector, the load connection voltage changes, and the comparison unit outputs a signal to the control module. The control module controls the charging switch module to turn on, and the charging voltage is provided to the charging plug connector, so that the charging load can be charged. During the charging process, the charging load and the charging plug connector are loose, which also causes the load connection voltage to change. The control module can control the charging switch module to turn off in time, and use the comparison unit to compare the load connection voltage with the reference voltage, so that the detection result is more accurate. In addition, in the process of tending to be fully charged, the charging current will gradually decrease, and the charging current can be sampled by the current sampling module. The control module can also control the charging switch module to turn off according to the change of the charging current. The design has accurate detection, automatic charging operation, and is safe and reliable to use.

[0008] According to some embodiments of the present utility model, the charging plug connector includes a positive terminal and a negative terminal, the positive terminal is connected to the tail end of the charging switch module, the negative terminal is grounded, the charging plug connector is connected to a charging load, and the positive terminal and the negative terminal are conducted through the charging load.

[0009] According to some embodiments of the present invention, the sampling and comparing module further includes a diode D1 , an anode of the diode D1 is connected to the first input terminal of the comparing unit, and a cathode of the diode D1 is connected to the tail end of the charging switch module.

[0010] According to some embodiments of the present invention, the reference unit includes a resistor R19 and a resistor R20, one end of the resistor R19 is connected to a power supply, the other end of the resistor R19 is respectively connected to one end of the resistor R20 and the second input end of the comparison unit, and the other end of the resistor R20 is grounded.

[0011] According to some embodiments of the present utility model, the charging switch module includes a switch tube Q1, a switch tube Q5 and a resistor R2, the input end of the switch tube Q1 is respectively connected to the output end of the power supply voltage regulating module and one end of the resistor R2, the output end of the switch tube Q1 is respectively connected to the other end of the resistor R2 and the charging plug, the input end of the switch tube Q5 is connected to the controlled end of the switch tube Q1, the output end of the switch tube Q5 is grounded, and the control module is connected to the controlled end of the switch tube Q5.

[0012] According to some embodiments of the present utility model, the current sampling module includes a sampling resistor R3, a resistor R7 and a resistor R8, one end of the sampling resistor R3 is respectively connected to the output end of the power supply voltage regulation module and one end of the resistor R7, the other end of the sampling resistor R3 is connected to the head end of the charging switch module and one end of the resistor R8, and the control module is respectively connected to the other end of the resistor R7 and the other end of the resistor R8.

[0013] According to some embodiments of the utility model, the power supply voltage regulation module includes an energy storage step-down unit and a starting switch unit, the input end of the starting switch unit is used to connect to the power supply, the output end of the starting switch unit is connected to the input end of the energy storage step-down unit, and the output end of the energy storage step-down unit is connected to the head end of the charging switch module.

[0014] According to some embodiments of the utility model, the energy storage step-down unit includes a switching power supply chip and an energy storage inductor L1, the input end of the switching power supply chip is connected to the output end of the starting switch unit, the output end of the switching power supply chip is connected to one end of the energy storage inductor L1, and the other end of the energy storage inductor L1 is connected to the head end of the charging switch module.

[0015] According to some embodiments of the present utility model, the starting switch unit includes a first switch component, a second switch component and a switch tube Q4, the first switch component includes a switch tube Q2 and a first diode connected in parallel, the second switch component includes a switch tube Q3 and a second diode connected in parallel, the positive electrode of the first diode is used to connect to the power supply, the negative electrode of the first diode is connected to the negative electrode of the second diode, the positive electrode of the second diode is connected to the input end of the energy storage step-down unit, the input end of the switch tube Q4 is respectively connected to the controlled end of the switch tube Q2 and the controlled end of the switch tube Q3, the output end of the switch tube Q4 is grounded, and the control module is connected to the controlled end of the switch tube Q4.

[0016] The charging device according to the second aspect of the present invention includes the overcharge prevention hot-swap charging circuit disclosed in any one of the above embodiments.

[0017] The charging device according to the embodiment of the utility model has at least the following beneficial effects:

[0018] The charging device of the utility model applies the overcharge prevention hot-swap charging circuit disclosed in any of the above embodiments, has accurate detection, automatic charging operation, and is safe and reliable to use.

[0019] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0021] Figure 1 This is a principle structure block diagram of one embodiment of the overcharge prevention hot-swap charging circuit of the utility model;

[0022] Figure 2 A circuit diagram of one embodiment of a power supply voltage regulator module;

[0023] Figure 3 The circuit diagram of one embodiment of a sampling and comparison module, a charging switch module and a current sampling module is shown.

[0024] Reference numerals:

[0025] Power supply voltage regulation module 100; energy storage voltage reduction unit 110; start switch unit 120; first switch element 121; second switch element 122; charging switch module 200; sampling and comparison module 300; comparison unit 310; reference unit 320; current sampling module 400; control module 500; charging plug connector 600. DETAILED DESCRIPTION

[0026] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0027] In the description of the present invention, it should be understood that descriptions involving orientation, such as the orientations or positional relationships indicated by terms such as "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside", etc., are 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, and do not indicate or imply 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.

[0028] In the description of the present utility model, "several" means one or more, "more" means more than two, "greater than", "less than", "exceed" etc. are understood to exclude the number itself, and "above", "below", "within" etc. are understood to include the number itself. If there is a description of "first" or "second", it is only used for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0029] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" 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 components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0030] like Figure 1-Figure 3 As shown, according to an embodiment of the first aspect of the utility model, an overcharge prevention hot-swap charging circuit includes a power supply voltage regulating module 100, a charging switch module 200, a sampling and comparison module 300, a current sampling module 400 and a control module 500, wherein the input end of the power supply voltage regulating module 100 is used to connect to a power supply, and the power supply voltage regulating module 100 is used to modulate the output voltage of the power supply into a charging voltage, and the output end of the power supply voltage regulating module 100 is connected to the head end of the charging switch module 200, and the tail end of the charging switch module 200 is connected to a charging plug 600, and the charging plug 600 Used to connect with the charging load, the sampling and comparison module 300 includes a comparison unit 310 and a reference unit 320, the first input end of the comparison unit 310 is connected to the tail end of the charging switch module 200, the reference unit 320 is used to provide a reference voltage, the second input end of the comparison unit 310 is connected to the reference unit 320, the sampling end of the current sampling module 400 is connected to the head end of the charging switch module 200, and the control module 500 is respectively connected to the output end of the current sampling module 400, the output end of the comparison unit 310 and the controlled end of the charging switch module 200.

[0031] The control module 500 may be selected from the MCU or CPU and its associated circuits, the comparison unit 310 may be selected from a conventional comparator, and the charging plug connector 600 may be selected according to actual conditions to be a model that can match the charging load.

[0032] In the utility model, before the charging load is connected to the charging plug connector 600, the first input end of the comparison unit 310 obtains the load connection voltage at the charging plug connector 600. Since there is no charging load connected, the control module 500 can learn from the signal output by the comparison unit 310 how the load connection voltage is compared with the reference voltage provided by the reference unit 320, and learn that there is no charging load connected, the charging switch module 200 remains turned off, and there is no charging voltage input to the charging plug connector 600. When the charging load is connected to the charging plug connector 600, the load connection voltage changes, and the comparison unit 310 outputs a signal to the control module 500, and the control module 500 controls the charging switch module 200 to turn off the charging load. 00 is turned on, and the charging voltage is provided to the charging plug 600, so as to charge the charging load. During the charging process, the charging load and the charging plug 600 become loose, which will also cause the load access voltage to change. The control module 500 can promptly control the charging switch module 200 to turn off, and use the comparison unit 310 to compare the load access voltage with the reference voltage, so that the detection result is more accurate. In addition, in the process of being fully charged, the charging current will gradually decrease. The charging current can be sampled by the current sampling module 400, and the control module 500 can also control the charging switch module 200 to turn off according to the change of the charging current. The design has accurate detection, automatic charging operation, and is safe and reliable to use.

[0033] In some embodiments of the present invention, the charging plug connector 600 includes a positive terminal and a negative terminal, the positive terminal is connected to the tail end of the charging switch module 200, the negative terminal is grounded, the charging plug connector 600 is connected to a charging load, and the positive terminal and the negative terminal are conducted through the charging load.

[0034] Specifically, when the charging load is not connected to the charging plug connector 600, the positive terminal and the negative terminal are disconnected, the first input end of the comparison unit 310 detects a high-level load connection voltage, the load connection voltage is compared with the reference voltage, thereby generating a first feedback voltage, and the control module 500 controls the charging switch module 200 to be disconnected according to the first feedback voltage. When the charging load is connected to the charging plug connector 600, the positive terminal and the negative terminal are connected through the charging load, the first input end of the comparison unit 310 detects a low-level load connection voltage, the load connection voltage is compared with the reference voltage, thereby generating a second feedback voltage, and the control module 500 controls the charging switch module 200 to be turned on according to the second feedback voltage.

[0035] In some embodiments of the present invention, the sampling and comparing module 300 further includes a diode D1 , the anode of the diode D1 is connected to the first input terminal of the comparing unit 310 , and the cathode of the diode D1 is connected to the tail end of the charging switch module 200 .

[0036] The diode D1 is unidirectionally cut off. When the charging switch module 200 is turned on, the charging voltage can be limited from entering the comparison unit 310 to prevent the comparison unit 310 from being affected in its detection and judgment.

[0037] In some embodiments of the present invention, the reference unit 320 includes a resistor R19 and a resistor R20, one end of the resistor R19 is connected to the power supply, the other end of the resistor R19 is respectively connected to one end of the resistor R20 and the second input end of the comparison unit 310, the other end of the resistor R20 is grounded, and the resistor R19 and the resistor R20 are used to form a voltage divider, and the terminal voltage between the other end of the resistor R19 and one end of the resistor R20 forms a reference voltage.

[0038] In some embodiments of the present invention, Figure 3 As shown, the charging switch module 200 includes a switch tube Q1, a switch tube Q5 and a resistor R2. The input end of the switch tube Q1 is respectively connected to the output end of the power supply voltage regulating module 100 and one end of the resistor R2, the output end of the switch tube Q1 is respectively connected to the other end of the resistor R2 and the charging plug 600, the input end of the switch tube Q5 is connected to the controlled end of the switch tube Q1, the output end of the switch tube Q5 is grounded, and the control module 500 is connected to the controlled end of the switch tube Q5.

[0039] Among them, the resistor R2 is a resistor with a relatively high resistance. When the switch tube Q1 is turned off, the current passing through the resistor R2 is insufficient to charge the charging load. The charging load is connected to the charging plug 600, which can make the voltage at the sampling point connected to the first input end of the comparison unit 310 drop, so that the output end of the comparison unit 310 outputs a second feedback voltage.

[0040] In some embodiments of the present utility model, the current sampling module 400 includes a sampling resistor R3, a resistor R7 and a resistor R8, one end of the sampling resistor R3 is respectively connected to the output end of the power supply voltage regulating module 100 and one end of the resistor R7, the other end of the sampling resistor R3 is connected to the first end of the charging switch module 200 and one end of the resistor R8, and the control module 500 is respectively connected to the other end of the resistor R7 and the other end of the resistor R8.

[0041] The charging current passes through the sampling resistor R3, thereby forming a sampling voltage on the sampling resistor R3. The terminal voltages are obtained by using resistors R7 and R8, and then the sampling voltage on the sampling resistor R3 is obtained, so as to calculate the size of the charging current. When the charging current decreases, indicating that the charging load is close to full charge, the control module 500 controls the charging switch module 200 to turn off.

[0042] In some embodiments of the present invention, Figure 2 As shown, the power supply voltage regulation module 100 includes an energy storage buck unit 110 and a starting switch unit 120, wherein the input end of the starting switch unit 120 is used to connect to the power supply, the output end of the starting switch unit 120 is connected to the input end of the energy storage buck unit 110, and the output end of the energy storage buck unit 110 is connected to the head end of the charging switch module 200.

[0043] The control module 500 may also be provided with operation buttons or wireless communication chips. The user may send control instructions to the control module 500. The control module 500 controls the start switch unit 120 to close according to the control instructions, so that the power supply supplies power to the energy storage step-down unit 110. The user may also control the start switch unit 120 to open, so as to stop supplying power to the energy storage step-down unit 110, thereby improving safety performance.

[0044] In some embodiments of the present utility model, the energy storage step-down unit 110 includes a switching power supply chip and an energy storage inductor L1, the input end of the switching power supply chip is connected to the output end of the starting switch unit 120, the output end of the switching power supply chip is connected to one end of the energy storage inductor L1, and the other end of the energy storage inductor L1 is connected to the head end of the charging switch module 200.

[0045] The switching power supply chip can be selected from conventional switching power supply chips. The switching power supply chip modulates the input voltage, outputs a switching voltage signal, stores energy and reduces the voltage in the energy storage inductor L1, and forms a charging voltage.

[0046] In some embodiments of the present utility model, the starting switch unit 120 includes a first switch element 121, a second switch element 122 and a switch tube Q4, the first switch element 121 includes a switch tube Q2 and a first diode connected in parallel, the second switch element 122 includes a switch tube Q3 and a second diode connected in parallel, the positive electrode of the first diode is used to connect to the power supply, the negative electrode of the first diode is connected to the negative electrode of the second diode, the positive electrode of the second diode is connected to the input end of the energy storage buck unit 110, the input end of the switch tube Q4 is respectively connected to the controlled end of the switch tube Q2 and the controlled end of the switch tube Q3, the output end of the switch tube Q4 is grounded, and the control module 500 is connected to the controlled end of the switch tube Q4.

[0047] The first switch element 121 and the second switch element 122 can be connected using an integrated IGBT device and connected in reverse series. When the switch tube Q4 is turned on, the first switch element 121 and the second switch element 122 can be controlled to be turned on. The power supply can be an AC power supply. The IGBT device connected in reverse series can convert the voltage output by the AC power supply into DC power to provide it to the energy storage step-down unit 110.

[0048] According to the charging device of the second embodiment of the utility model, Figure 1-Figure 3 As shown, it includes the anti-overcharging hot-swap charging circuit disclosed in any of the above embodiments.

[0049] The charging device of the utility model applies the overcharge prevention hot-swap charging circuit disclosed in any of the above embodiments, has accurate detection, automatic charging operation, and is safe and reliable to use.

[0050] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0051] Although the embodiments of the present invention have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. An overcharge prevention hot-swap charging circuit, characterized in that: include: A power supply voltage regulating module, wherein the input end of the power supply voltage regulating module is used to be connected to a power supply, and the power supply voltage regulating module is used to modulate the output voltage of the power supply into a charging voltage; A charging switch module, wherein the output end of the power supply voltage regulating module is connected to the head end of the charging switch module, and the tail end of the charging switch module is connected to the charging plug connector, and the charging plug connector is used to connect to a charging load; A sampling and comparison module, comprising a comparison unit and a reference unit, wherein a first input terminal of the comparison unit is connected to a tail end of the charging switch module, the reference unit is used to provide a reference voltage, and a second input terminal of the comparison unit is connected to the reference unit; A current sampling module, wherein a sampling end of the current sampling module is connected to a first end of the charging switch module; A control module, connected to the output end of the current sampling module, the output end of the comparison unit and the controlled end of the charging switch module respectively; The reference unit includes a resistor R19 and a resistor R20, one end of the resistor R19 is connected to the power supply, the other end of the resistor R19 is respectively connected to one end of the resistor R20 and the second input end of the comparison unit, and the other end of the resistor R20 is grounded; The charging switch module includes a switch tube Q1, a switch tube Q5 and a resistor R2, the input end of the switch tube Q1 is respectively connected to the output end of the power supply voltage regulator module and one end of the resistor R2, the output end of the switch tube Q1 is respectively connected to the other end of the resistor R2 and the charging plug connector, the input end of the switch tube Q5 is connected to the controlled end of the switch tube Q1, the output end of the switch tube Q5 is grounded, and the control module is connected to the controlled end of the switch tube Q5; The current sampling module includes a sampling resistor R3, a resistor R7 and a resistor R8, one end of the sampling resistor R3 is respectively connected to the output end of the power supply voltage regulating module and one end of the resistor R7, the other end of the sampling resistor R3 is connected to the first end of the charging switch module and one end of the resistor R8, and the control module is respectively connected to the other end of the resistor R7 and the other end of the resistor R8.

2. The overcharge prevention hot-swap charging circuit according to claim 1, characterized in that: The charging plug connector includes a positive terminal and a negative terminal, the positive terminal is connected to the tail end of the charging switch module, the negative terminal is grounded, the charging plug connector is connected to a charging load, and the positive terminal and the negative terminal are conducted through the charging load.

3. The overcharge prevention hot-swap charging circuit according to claim 1, characterized in that: The sampling and comparing module further includes a diode D1 , an anode of the diode D1 is connected to the first input terminal of the comparing unit, and a cathode of the diode D1 is connected to the tail end of the charging switch module.

4. The overcharge prevention hot-swap charging circuit according to claim 1, characterized in that: The power supply voltage regulation module includes an energy storage step-down unit and a starting switch unit, wherein the input end of the starting switch unit is used to connect to the power supply, the output end of the starting switch unit is connected to the input end of the energy storage step-down unit, and the output end of the energy storage step-down unit is connected to the head end of the charging switch module.

5. The overcharge prevention hot-swap charging circuit according to claim 4, characterized in that: The energy storage and voltage reduction unit includes a switching power supply chip and an energy storage inductor L1. The input end of the switching power supply chip is connected to the output end of the starting switch unit, the output end of the switching power supply chip is connected to one end of the energy storage inductor L1, and the other end of the energy storage inductor L1 is connected to the first end of the charging switch module.

6. The overcharge prevention hot-swap charging circuit according to claim 4, characterized in that: The starting switch unit includes a first switch component, a second switch component and a switch tube Q4. The first switch component includes a switch tube Q2 and a first diode connected in parallel. The second switch component includes a switch tube Q3 and a second diode connected in parallel. The positive electrode of the first diode is used to be connected to a power supply. The negative electrode of the first diode is connected to the negative electrode of the second diode. The positive electrode of the second diode is connected to the input end of the energy storage buck unit. The input end of the switch tube Q4 is respectively connected to the controlled end of the switch tube Q2 and the controlled end of the switch tube Q3. The output end of the switch tube Q4 is grounded. The control module is connected to the controlled end of the switch tube Q4.

7. A charging device, characterized in that: It comprises the overcharge prevention hot-swap charging circuit as described in any one of claims 1 to 6.

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