Charging systems and electronic products

Abstract

The utility model provides a charging system and an electronic product; the charging system comprises: a current adjustment module, a control module, a first voltage detection module, a first voltage comparison module and a counting module; the first voltage comparison module is respectively connected to the first voltage detection module and the control module; the control module is also respectively connected to the current adjustment module and the counting module; the counting module is also connected to the first voltage comparison module; the utility model adjusts the charging current through a current adjustment module, so that a charging current different from that in the constant current charging stage can be provided in the charging stage after the battery is charged with a constant current, so when charging, it is not necessary to separately design an operational amplifier for maintaining the voltage of the battery as in the constant voltage charging stage in the prior art, and it is only necessary to use the same current adjustment module in parallel with the constant current charging stage, thereby saving the layout area of ​​the integrated circuit, occupying less circuit resources and reducing the cost.

Description

Technical Field

[0001] The utility model relates to the field of electricity, in particular to a charging technology, and more particularly to a charging system and an electronic product. Background Art

[0002] Lithium batteries are currently widely used, and their equivalent model is a parasitic resistor connected in series with a battery cell.

[0003] Traditional lithium battery charging is divided into three stages: trickle charging, constant current charging and constant voltage charging. Among them, since constant current charging requires an operational amplifier, constant voltage charging requires a separate operational amplifier to ensure constant voltage. This will result in the charging circuit occupying a large amount of circuit resources and high cost. Utility Model Content

[0004] The purpose of the utility model is to provide a charging system and an electronic product, which are used to solve the problems pointed out in the above background technology.

[0005] In a first aspect, the utility model provides a charging system, which is applied to a battery, and the charging system includes: a current adjustment module, a control module, a first voltage detection module, a first voltage comparison module and a counting module; wherein the first voltage comparison module is respectively connected to the first voltage detection module and the control module; the control module is also respectively connected to the current adjustment module and the counting module; the counting module is also connected to the first voltage comparison module.

[0006] In the utility model, the charging current is adjusted by a current adjustment module, so that a charging current different from that in the constant current charging stage can be provided in the charging stage after the constant current charging of the battery. Therefore, when charging, there is no need to design an operational amplifier separately for maintaining the voltage of the battery as in the constant voltage charging stage in the prior art. It is only necessary to use the same current adjustment module in parallel with the constant current charging stage, thereby saving the layout area of ​​the integrated circuit, occupying less circuit resources, and reducing the cost.

[0007] In an implementation of the first aspect, the first voltage comparison module includes: a comparator; the positive input terminal of the comparator is connected to the first voltage detection module, the negative input terminal of the comparator is connected to one end that outputs the reference voltage, and the output terminal of the comparator is respectively connected to the control module and the counting module.

[0008] In an implementation manner of the first aspect, the charging system further includes: a reference voltage source; and the reference voltage source is connected to the first voltage comparison module.

[0009] In an implementation of the first aspect, the current adjustment module includes: a first operational amplifier, a second operational amplifier, a resistor, a field effect transistor, a first current source, a second current source and a peripheral circuit; wherein, one end of the first current source and one end of the second current source are both grounded, and the other end of the first current source is connected to the negative input end of the first operational amplifier, the first end of the field effect transistor and the peripheral circuit; the other end of the second current source is connected to the positive input end of the first operational amplifier and the peripheral circuit; the output end of the first operational amplifier is connected to the second end of the field effect transistor; the third end of the field effect transistor is connected to one end of the resistor and the negative input end of the second operational amplifier; the positive input end of the second operational amplifier is connected to the reference voltage source, and the output end of the second operational amplifier is connected to the control module.

[0010] In an implementation of the first aspect, the charging system further includes: a second voltage detection module and a second voltage comparison module; wherein the second voltage comparison module is connected to the control module and the second voltage detection module respectively.

[0011] In a second aspect, the utility model provides an electronic product, comprising: a battery and the above-mentioned charging system; wherein the charging system is connected to the battery, and the charging system is used to charge the battery.

[0012] As described above, the charging system and electronic product of the utility model have the following beneficial effects:

[0013] (1) Compared with the prior art, the charging system provided by the utility model reduces the layout area of ​​the integrated circuit, thereby reducing the cost.

[0014] (2) Compared with the prior art, the charging system provided by the utility model shortens the existing constant voltage charging time and improves the charging time efficiency ratio.

[0015] (3) The charging system provided by the utility model only detects the end of the battery voltage during the charging stage after constant current charging. During charging, only one parameter is judged, so that the judgment accuracy is high, the end is relatively accurate, and the efficiency is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Shown is a functional block diagram of a charging system according to an embodiment of the present utility model.

[0017] Figure 2 Shown is a schematic diagram of the structure of the charging system described in an embodiment of the utility model.

[0018] Figure 3Shown is a schematic diagram of the charging process of the charging system according to an embodiment of the present utility model. DETAILED DESCRIPTION

[0019] The following describes the implementation of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific implementations, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0020] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention. The illustrations only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0021] See also Figures 1 to 3 The following embodiments of the utility model provide a charging system and an electronic product. Compared with the prior art, the charging system provided by the utility model reduces the layout area of ​​the integrated circuit, thereby reducing the cost; the charging system provided by the utility model shortens the existing constant voltage charging time and improves the charging time efficiency ratio; the charging system provided by the utility model only detects the end of the battery voltage in the charging stage after the constant current charging, and only judges one parameter during charging, so that the judgment accuracy is high, the end is relatively accurate, and the efficiency is high.

[0022] The technical solutions in the embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0023] In one embodiment, the utility model provides a charging system for a battery.

[0024] In one embodiment, the battery includes but is not limited to a lithium battery; for example, it may also be a lead-acid battery.

[0025] like Figure 1 As shown, in one embodiment, the charging system includes: a current adjustment module 1 , a control module 2 , a first voltage detection module 3 , a first voltage comparison module 4 and a counting module 5 .

[0026] Specifically, the first voltage comparison module 4 is connected to the first voltage detection module 3 and the control module 2 respectively; the control module 2 is also connected to the current adjustment module 1 and the counting module 5 respectively; the counting module 5 is also connected to the first voltage comparison module 4 .

[0027] It should be noted that, in this embodiment, the control module 2 is used to control the current adjustment module 1 to output a first current when the battery voltage of the battery meets a preset condition, and to charge the battery using a constant current charging method in which the charging current is the first current, so that the battery voltage reaches the maximum voltage allowed by the battery for the first time, and to control the current adjustment module 1 to output a second current when the battery voltage reaches the maximum voltage for the first time, and to charge the battery using a constant current charging method in which the charging current is the second current, until the battery voltage reaches the maximum voltage again and charging is stopped; the second current is less than the first current.

[0028] In one embodiment, the above-mentioned charging process of "when the battery voltage reaches the maximum voltage for the first time, controlling the current adjustment module 1 to output the second current, and charging the battery using a constant current charging method in which the charging current is the second current, until the battery voltage reaches the maximum voltage again and charging is stopped" is defined as "quasi-constant voltage charging".

[0029] In one embodiment, the preset condition is that the battery voltage is greater than or equal to the initial voltage and less than the maximum voltage; and the initial voltage is less than the maximum voltage.

[0030] It should be noted that the specific value of the initial voltage is not a condition limiting the present invention. In practical applications, it can be set according to specific application scenarios (for example, different batteries have different corresponding maximum voltages); for example, Figure 3 In the corresponding embodiment, the initial voltage is set to 3V and the maximum voltage is 4.2V.

[0031] It should be noted that, in this embodiment, the first voltage detection module 3 is used to detect the target voltage, and to output the target voltage to the first voltage comparison module 4; the first voltage comparison module 4 is used to compare the reference voltage and the target voltage, and to output a corresponding control signal to the control module 2 according to the comparison result, so that the control module 2 controls the current adjustment module 1 to output the first current or the second current according to the control signal.

[0032] It should be noted that the first voltage detection module 3 adopts conventional technical means in this field, so its working principle will not be described in detail here.

[0033] In one embodiment, the target voltage is the battery voltage minus the initial voltage.

[0034] It should be noted that the first voltage comparison module 4 generates two different control signals, namely a high level (1) control signal and a low level (0) control signal, by comparing the reference voltage and the target voltage.

[0035] It should be noted that, in this embodiment, the counting module 5 is used to realize, according to the control signal, recording the count value as the first value when the battery voltage reaches the maximum voltage for the first time, and to realize recording the count value as the second value when the battery voltage reaches the maximum voltage again, so that the control module 2 controls the current adjustment module 1 to output the first current or the second current according to the count value and the control signal; the first value is different from the second value.

[0036] In one embodiment, the counting module 5 includes a counter; specifically, the counter is connected to the control module 2 and the first voltage comparison module 4 respectively.

[0037] It should be noted that, in this embodiment, when the count value is the first value, it indicates that the battery voltage reaches the maximum voltage for the first time; when the count value is the second value, it indicates that the battery voltage reaches the maximum voltage again; and the second value is different from the first value.

[0038] It should be noted that the specific settings of the first value and the second value are not used as conditions to limit the present invention, and can be set according to specific application scenarios in actual applications; for example, the first value is set to 1 and the second value is set to 2.

[0039] In one embodiment, the count value is the third value at all times except the first value and the second value.

[0040] It should be noted that the third value is different from the first value and the second value; for example, the third value is set to 0.

[0041] It should be noted that when the battery voltage meets the preset conditions, whether to perform constant current charging or quasi-constant voltage charging is determined according to the count value; specifically, if the count value is the third value (the control signal is at a low level), constant current charging is performed, that is, the control module 2 controls the current adjustment module 1 to output the first current; in the constant current charging stage, the count value starts to be the third value until the battery voltage reaches the highest voltage for the first time, the count value changes from the third value to the first value, at this time, the control signal also changes from a low level to a high level, and quasi-constant voltage charging is started, that is, the control module 2 controls the current adjustment module 1 to output the second current; in the quasi-constant voltage charging stage, the count value is always the first value, but the control signal is at a low level, until the battery voltage reaches the highest voltage again, the count value changes from the first value to the second value, and the control signal also changes from a low level to a high level, at this time, charging is stopped.

[0042] like Figure 1 and Figure 2 As shown, in one embodiment, the first voltage comparison module 4 includes: a comparator 41 .

[0043] Specifically, the positive input terminal of the comparator 41 is connected to the first voltage detection module 3, the negative input terminal of the comparator 41 is connected to one end outputting the reference voltage, and the output terminal of the comparator 41 is respectively connected to the control module 2 and the counting module 5; if the target voltage is greater than or equal to the reference voltage, the comparator 41 outputs a high-level control signal; conversely, if the target voltage is less than the reference voltage, the comparator 41 outputs a low-level control signal.

[0044] In this embodiment, it is defined that when the target voltage is less than the reference voltage, the battery voltage has not reached the maximum voltage; when the target voltage is greater than or equal to the reference voltage, the battery voltage has reached the maximum voltage.

[0045] like Figure 1 and Figure 2 As shown, in one embodiment, the charging system further includes: a reference voltage source 6.

[0046] Specifically, the reference voltage source 6 is connected to the first voltage comparison module 4 , and the reference voltage source 6 is used to provide the reference voltage.

[0047] In one embodiment, the reference voltage is 1.2V.

[0048] In one embodiment, the current adjustment module 1 adjusts the charging current by adjusting the amplification ratio of the operational amplifier.

[0049] like Figure 1 and Figure 2As shown, in one embodiment, the current adjustment module 1 includes: a first operational amplifier 11 , a second operational amplifier 12 , a resistor 13 , a field effect transistor 14 , a first current source 15 , a second current source 16 and a peripheral circuit 17 .

[0050] Specifically, one end of the first current source 15 and one end of the second current source 16 are both grounded, the other end of the first current source 15 is connected to the negative input end of the first operational amplifier 11, the first end of the field effect tube 14 and the peripheral circuit 17; the other end of the second current source 16 is connected to the positive input end of the first operational amplifier 11 and the peripheral circuit 17; the output end of the first operational amplifier 11 is connected to the second end of the field effect tube 14; the third end of the field effect tube 14 is connected to one end of the resistor 13 and the negative input end of the second operational amplifier 12; the positive input end of the second operational amplifier 12 is connected to the reference voltage source 6, and the output end of the second operational amplifier 12 is connected to the control module 2.

[0051] A standard reference current is provided by the reference voltage source 6 , the second operational amplifier 12 and the resistor 13 . The first current source 15 and the second current source 16 are both integer multiples of the reference current.

[0052] It should be noted that the charging current is adjusted using the current adjustment module 1 described above, and the specific working principle adopted is the conventional technology in this field, that is, the amplification ratio of the operational amplifier is adjusted through the design of the peripheral circuit 17, thereby adjusting the charging current.

[0053] like Figure 1 As shown, in one embodiment, the charging system further includes: a second voltage detection module 7 and a second voltage comparison module 8.

[0054] Specifically, the second voltage detection module 7 is connected to the second voltage comparison module 8, the second voltage detection module 7 is used to detect the battery voltage, and to output the battery voltage to the second voltage comparison module 8; the second voltage comparison module 8 is connected to the control module 2, the second voltage comparison module 8 is used to determine whether the battery voltage meets the preset condition, and to charge the battery using a trickle charging method with a charging current of a third current when the battery voltage does not meet the preset condition until the battery voltage meets the preset condition; the third current is less than the first current.

[0055] It should be noted that the second voltage detection module 7 and the second voltage comparison module 8 both adopt conventional technical means in the art, so their working principles are not described in detail here.

[0056] like Figure 3 As shown, in one embodiment, the third current (ie Figure 3 The current in the trickle charging stage) is equal to the second current (i.e. Figure 3 The current in the quasi-constant voltage charging stage).

[0057] Specifically, when the battery voltage does not meet the preset condition, the control module 2 controls the current adjustment module 1 to output a third current equal to the second current, so as to perform trickle charging on the battery.

[0058] It should be noted that quasi-constant voltage charging is a modification of the last process of battery charging. The previous trickle charging and constant current charging processes are the same as the traditional charging process. In the constant current charging stage, the battery voltage gradually increases. When it reaches the maximum voltage of the battery, the charging current will be reduced to a small current (corresponding to the second current mentioned above). At this time, due to the parasitic resistance of the battery, the battery voltage will drop. Then, charging will continue at this small current, and the battery voltage will increase again. When the maximum charging voltage is reached for the second time, charging is completed.

[0059] Since the quasi-constant voltage charging stage is only a charging current different from the constant current, there is no need to design a separate operational amplifier to maintain the battery voltage during charging. It is only necessary to use the same current control operational amplifier (corresponding to the above-mentioned current adjustment module 1) in parallel with the constant current stage to perform two current adjustments to achieve the purpose of fully charging the battery, thereby saving the layout area of ​​the integrated circuit and reducing the cost.

[0060] In one embodiment, the second current is 1 / 10 of the first current.

[0061] The working principle of the charging system of the present utility model is further explained below through specific embodiments.

[0062] like Figure 3 As shown, in one embodiment, a lithium battery is taken as an example; specifically, the battery voltage is too low (lower than 3V), the activity of the battery is reduced, and the lithium battery needs to be trickle charged with a small current (corresponding to the third current mentioned above) to gradually enhance the activity of the battery, which can extend the service life of the battery; when the battery voltage gradually increases, constant current charging is performed; when the battery voltage reaches the maximum allowable voltage (4.2V), the charging current is reduced to a small current (corresponding to the second current mentioned above), at which time the battery voltage will drop, and then continue to charge according to this small current (corresponding to the second current mentioned above), the battery voltage will increase again until the maximum voltage, and charging will stop.

[0063] Specifically, combined Figure 3In the constant current charging stage, the battery voltage is greater than 3V and less than 4.2V. At this time, the target voltage is less than the reference voltage of 1.2V. The first voltage comparison module 4 outputs a low-level control signal, that is, the control module 2 controls the current adjustment module 1 to output the first current according to the low-level control signal, so as to charge the battery in a constant current charging manner according to the first current, until the battery voltage reaches 4.2V (the battery voltage reaches the maximum voltage for the first time). At this time, the target voltage is equal to the reference voltage of 1.2V, and the first voltage comparison module 4 outputs a high-level control signal, so that the control module 2 controls the current adjustment module 1 to output the second current according to the high-level control signal, and continues to charge the battery in a constant current charging manner according to the second current. During this charging process, the target voltage is still less than the reference voltage of 1.2V, but the control module 2 still controls the current adjustment module 1 to output the second current until the battery voltage reaches the maximum voltage of 4.2V again, and charging is stopped.

[0064] It should be noted that the use of quasi-constant voltage charging instead of constant voltage charging in the prior art can shorten the existing constant voltage charging time during the quasi-constant voltage charging stage, reduce the layout area of ​​the integrated circuit, reduce costs, and also make the battery more fully charged.

[0065] It should be noted that due to quasi-constant voltage charging, only the charging voltage is detected when charging. During charging, only one parameter is judged. The chip has high judgment accuracy, the termination is relatively accurate, and the efficiency is high. For traditional constant voltage charging, since the battery voltage must be guaranteed at the same time, the charging current must be detected at the same time. At this time, the two parameters are greatly affected relative to one parameter, the charging time is longer, and the accuracy is lower.

[0066] In one embodiment, the utility model further provides an electronic product, which includes: a battery and the above-mentioned charging system.

[0067] Specifically, the charging system is connected to the battery, and the charging system is used to charge the battery.

[0068] It should be noted that by using the above charging system to charge the batteries of electronic products, the cost of the charger is reduced by 30% compared with the original cost, and the chip product yield is also greatly improved compared with the previous cost.

[0069] In the several embodiments provided by the present utility model, it should be understood that the disclosed system, device or method can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of modules / units is only a logical function division. There may be other division methods in actual implementation. For example, multiple modules or units can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or modules or units, which can be electrical, mechanical or other forms.

[0070] The modules / units described as separate components may or may not be physically separated, and the components displayed as modules / units may or may not be physical modules, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules / units may be selected according to actual needs to achieve the purpose of the embodiments of the utility model. For example, the functional modules / units in the various embodiments of the utility model may be integrated into one processing module, or each module / unit may exist physically separately, or two or more modules / units may be integrated into one module / unit.

[0071] Those skilled in the art should further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in terms of function in the above description. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present utility model.

[0072] The descriptions of the processes or structures corresponding to the above-mentioned figures have different emphases. For parts that are not described in detail in a certain process or structure, please refer to the relevant descriptions of other processes or structures.

[0073] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the technology may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed in the present invention shall still be covered by the claims of the present invention.

Claims

1. A charging system, applied to a battery, characterized in that: The charging system includes: a current adjustment module, a control module, a first voltage detection module, a first voltage comparison module and a counting module; wherein, The first voltage comparison module is connected to the first voltage detection module and the control module respectively; The control module is also connected to the current adjustment module and the counting module respectively; The counting module is also connected to the first voltage comparing module.

2. The charging system according to claim 1, characterized in that: The first voltage comparison module includes: a comparator; the positive input terminal of the comparator is connected to the first voltage detection module, the negative input terminal of the comparator is connected to one end of the output reference voltage, and the output terminal of the comparator is respectively connected to the control module and the counting module.

3. The charging system according to claim 1, characterized in that: The charging system further includes: a reference voltage source; the reference voltage source is connected to the first voltage comparison module.

4. The charging system according to claim 3, characterized in that: The current adjustment module comprises: a first operational amplifier, a second operational amplifier, a resistor, a field effect transistor, a first current source, a second current source and a peripheral circuit; wherein one end of the first current source and one end of the second current source are both grounded, the other end of the first current source is connected to the negative input end of the first operational amplifier, the first end of the field effect transistor and the peripheral circuit; the other end of the second current source is connected to the positive input end of the first operational amplifier and the peripheral circuit; The output end of the first operational amplifier is connected to the second end of the field effect transistor; The third end of the field effect tube is connected to one end of the resistor and the negative input end of the second operational amplifier; the positive input end of the second operational amplifier is connected to the reference voltage source, and the output end of the second operational amplifier is connected to the control module.

5. The charging system according to claim 1, characterized in that: The charging system further includes: a second voltage detection module and a second voltage comparison module; wherein, The second voltage comparison module is connected to the control module and the second voltage detection module respectively.

6. An electronic product, characterized in that: The electronic product comprises: a battery and a charging system according to any one of claims 1 to 5; wherein the charging system is connected to the battery, and the charging system is used to charge the battery.

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