CN219456432U

CN219456432U - Battery electric quantity detection circuit and electronic equipment

Info

Publication number: CN219456432U
Application number: CN202320059701.7U
Authority: CN
Inventors: 蒋锦茂; 贾鹏
Original assignee: Suzhou Saixin Electronic Technology Co ltd
Current assignee: Suzhou Saixin Electronic Technology Co ltd
Priority date: 2023-01-09
Filing date: 2023-01-09
Publication date: 2023-08-01
Anticipated expiration: 2033-01-09

Abstract

The utility model discloses a battery electric quantity detection circuit and electronic equipment. The battery power detection circuit includes: the device comprises a switch module, a protection module, a detection module, a voltage storage module and an electricity meter. The switch module is connected in series in a connecting loop of the battery assembly and the charging and discharging assembly; the switch module comprises a first connecting end, a second connecting end and a switch control end; the first connecting end is electrically connected with the battery assembly, and the second connecting end is electrically connected with the charge-discharge assembly; the protection module is respectively and electrically connected with the battery assembly and the switch control end; the voltage storage module is connected between the positive electrode end and the negative electrode end of the battery assembly; the fuel gauge is connected in parallel with two ends of the charge-discharge assembly and is electrically connected with the output end of the voltage storage module; the detection end of the detection module is electrically connected with the second connection end, and the output end of the detection module is electrically connected with the voltage storage module or the electricity meter and is used for detecting potential jump of the second connection end. The embodiment of the utility model can improve the accuracy of battery electric quantity detection.

Description

Battery electric quantity detection circuit and electronic equipment

Technical Field

The present utility model relates to the field of battery technologies, and in particular, to a battery power detection circuit and an electronic device.

Background

At present, due to the rising of portable electronic devices, particularly intelligent wearing devices such as electronic cigarettes, intelligent watches, true wireless Bluetooth headsets and the like, the capacity of batteries in the electronic devices is smaller and smaller, and the capacity of each battery is reduced from thousands of mAH to tens of mAH, even more than ten mAH.

For the electronic equipment formed by the small battery application system, when the electronic equipment is in standby or low voltage, the whole system can enter a shipping mode or an overdischarge protection state through lithium battery protection, and the lithium battery protection and the whole system are closed; and when the system is abnormal such as overcharging or overdischarging, the lithium battery protection can also shut down the whole system. When the whole system is closed, the method for detecting the battery voltage and the current in real time by the electricity meter is not feasible, and the simplest practical method is to sample the battery voltage of the battery assembly and calculate the battery electric quantity according to the corresponding relation between the battery voltage and the battery capacity. However, due to parasitic resistance of the battery assembly, when the system is charged by an access charger or discharged by an access electricity load, the battery voltage is suddenly changed, so that the voltage detection value is different from the actual battery voltage, and a larger misjudgment is generated on the battery capacity. In addition, different batteries correspond to different parasitic resistances, even the same battery has different voltage abrupt change values under different charging currents or discharging currents, so that the voltage abrupt change caused by the parasitic resistance is difficult to quantify. And, because of the battery characteristics, the parasitic resistance of the small-capacity battery is larger than that of the large-capacity battery, so that the battery voltage jump is larger during charging or discharging, and the error is larger. In summary, the existing battery power detection method has low accuracy, and particularly, the accuracy of the battery power detection result is difficult to be ensured when the system is turned from off to on.

Disclosure of Invention

The utility model provides a battery electric quantity detection circuit and electronic equipment, which are used for improving the accuracy of battery electric quantity detection.

In a first aspect, an embodiment of the present utility model provides a battery power detection circuit, including: the device comprises a switch module, a protection module, a detection module, a voltage storage module and an electricity meter;

the switch module is connected in series in a connecting loop of the battery assembly and the charging and discharging assembly; the switch module comprises a first connecting end, a second connecting end and a switch control end; the first connecting end is electrically connected with the battery assembly, and the second connecting end is electrically connected with the charge-discharge assembly;

the protection module is respectively and electrically connected with the battery assembly and the switch control end, and is used for controlling the conduction state of the switch module according to the running state of the battery assembly;

the voltage storage module is connected between the positive electrode end and the negative electrode end of the battery assembly; the voltage storage module is used for collecting and storing the battery voltage of the battery assembly;

the electricity meter is connected in parallel with two ends of the charging and discharging assembly and is electrically connected with the output end of the voltage storage module;

The detection end of the detection module is electrically connected with the second connection end, and the output end of the detection module is electrically connected with the voltage storage module and/or the fuel gauge; the detection module is used for detecting potential jump of the second connection end, so that the electricity meter calculates the battery electric quantity of the battery assembly when the potential jump of the second connection end is calculated according to the battery voltage stored by the voltage storage module before the potential jump of the second connection end.

Optionally, the voltage storage module includes: a pulse generating unit and a memory unit;

the pulse generation unit is electrically connected with the control end of the storage unit and is used for generating a pulse signal, and the pulse signal comprises a first potential and a second potential;

the first end of the storage unit is electrically connected with the positive electrode end of the battery assembly, the second end of the storage unit is electrically connected with the negative electrode end of the battery assembly, and the output end of the storage unit is used as the output end of the voltage storage module; the storage unit is used for storing and outputting the current battery voltage of the battery assembly when the pulse signal is at the first potential, and maintaining and outputting the battery voltage output by the storage unit when the pulse signal is at the second potential.

Optionally, the output end of the detection module is electrically connected with the control end of the pulse generation unit, the detection module is used for generating a first jump control signal according to the potential jump of the second connection end, so that the pulse generation unit controls the pulse signal to jump to the second potential, and the electricity meter is used for calculating the battery electric quantity of the battery assembly according to the battery voltage currently output by the storage unit.

Optionally, the output end of the detection module is electrically connected with the electricity meter, the pulse generating unit is used for generating pulse signals of which the first potential and the second potential are alternately output according to a preset frequency, and the electricity meter comprises a memory, and the memory is used for storing the battery voltage output by the storage unit; the detection module is used for generating a second jump control signal according to the potential jump of the second connection end so as to control the fuel gauge to calculate the battery electric quantity of the battery assembly when the potential jump of the second connection end is carried out according to the battery voltage stored by the memory before the potential jump of the second connection end.

Optionally, the storage unit includes a capacitor and a switch; the control end of the switch is used as the control end of the storage unit, and the first end of the switch is used as the first end of the storage unit; the second end of the switch is electrically connected with the first end of the capacitor and is used as the output end of the storage unit; the second end of the capacitor is used as the second end of the storage unit;

Or alternatively, the process may be performed,

the storage unit comprises an analog-to-digital converter, a control end of the analog-to-digital converter is used as a control end of the storage unit, a first end of the analog-to-digital converter is used as a first end of the storage unit, a second end of the analog-to-digital converter is used as a second end of the storage unit, and an output end of the analog-to-digital converter is used as an output end of the storage unit.

Optionally, the first connection end is electrically connected with the positive electrode end of the battery assembly, and the second connection end is electrically connected with the positive electrode end of the charge-discharge assembly;

or alternatively, the process may be performed,

the first connecting end is electrically connected with the negative electrode end of the battery assembly, and the second connecting end is electrically connected with the negative electrode end of the charge-discharge assembly.

Optionally, the switch module includes: a transistor; the control electrode of the transistor is electrically connected with the switch control end, the first electrode of the transistor is electrically connected with the first connecting end, and the second electrode of the transistor is electrically connected with the second connecting end;

or alternatively, the process may be performed,

the switch control terminal comprises a first control sub terminal and a second control sub terminal; the switch module includes: the first MOS tube and the second MOS tube; the grid electrode of the first MOS tube is electrically connected with the first control sub-end, the source electrode of the first MOS tube is electrically connected with the first connecting end, the drain electrode of the first MOS tube is electrically connected with the drain electrode of the second MOS tube, the grid electrode of the second MOS tube is electrically connected with the second control sub-end, and the source electrode of the second MOS tube is electrically connected with the second connecting end.

Optionally, the voltage storage module and the protection module are integrated on the same wafer, or the voltage storage module and the protection module are respectively disposed on different wafers.

Optionally, the detection module and the protection module are integrated on the same wafer, or the detection module and the protection module are respectively disposed on different wafers;

the switch module and the protection module are integrated on the same wafer, or the switch module and the protection module are respectively arranged on different wafers.

In a second aspect, an embodiment of the present utility model further provides an electronic device, including: a battery assembly and a battery charge detection circuit provided by any of the embodiments of the present utility model.

The battery electric quantity detection circuit provided by the embodiment of the utility model is provided with a switch module, a protection module, a detection module, a voltage storage module and an electric quantity meter. The voltage storage module is arranged between the positive electrode end and the negative electrode end of the battery assembly, so that the voltage storage module can collect the voltages at two ends of the battery assembly when the switch module is disconnected, and the battery voltage of the battery cell voltage can be accurately represented. And the detection module determines the time of other charge-discharge components connected to the circuit after the switch module is disconnected or determines the time of the protection module for controlling the switch module to be switched on again by detecting the potential jump of the second connection end of the switch module. And taking the time of potential jump of the second connecting end as a limit, acquiring accurate battery voltage by the voltage storage module before the potential jump, wherein the battery voltage can be regarded as the accurate battery voltage of the battery assembly at the time of the potential jump. Therefore, the electricity meter can accurately calculate the battery electric quantity of the battery assembly in the potential jump according to the battery voltage stored by the voltage storage module before the potential jump, thereby avoiding deviation of the battery electric quantity calculation result caused by the battery voltage measured value mutation due to current and parasitic resistance in the connection loop in the potential jump. In summary, compared with the prior art, the embodiment of the utility model stores the accurate battery voltage of the battery assembly in advance before the switch module is conducted by arranging the voltage storage module, and calculates the battery power by using the battery voltage stored in advance, so that the accuracy of battery power detection can be effectively improved.

It should be understood that the description in this section is not intended to identify key or critical features of the embodiments of the utility model or to delineate the scope of the utility model. Other features of the present utility model will become apparent from the description that follows.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the drawings required for the description of the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present utility model, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic structural diagram of a battery power detection circuit according to an embodiment of the present utility model;

FIG. 2 is a schematic diagram of a voltage storage module according to an embodiment of the present utility model;

fig. 3 is a schematic structural diagram of another battery power detection circuit according to an embodiment of the present utility model;

FIG. 4 is a schematic diagram of another voltage storage module according to an embodiment of the present utility model;

fig. 5 is a schematic structural diagram of another battery power detection circuit according to an embodiment of the present utility model;

FIG. 6 is a schematic diagram of a voltage storage module according to another embodiment of the present utility model;

FIG. 7 is a schematic diagram of a voltage storage module according to another embodiment of the present utility model;

fig. 8 is a schematic structural diagram of another battery level detection circuit according to an embodiment of the present utility model;

fig. 9 is a schematic structural diagram of another battery level detection circuit according to an embodiment of the present utility model;

fig. 10 is a schematic structural diagram of another battery level detection circuit according to an embodiment of the present utility model.

Detailed Description

In order that those skilled in the art will better understand the present utility model, a technical solution in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model, and it is apparent that the described embodiments are only some embodiments of the present utility model, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present utility model without making any inventive effort, shall fall within the scope of the present utility model.

It should be noted that the terms "first," "second," and the like in the description and the claims of the present utility model and the above figures are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that the embodiments of the utility model described herein may be implemented in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprise" and "have," as well as any variations thereof, are intended to cover a non-exclusive inclusion.

The embodiment of the utility model provides a battery electric quantity detection circuit which can be used for sampling and storing the battery voltage of a battery assembly in advance when the battery assembly of electronic equipment is not communicated with a connecting loop of a charging and discharging assembly and no charging current or discharging current exists in the connecting loop; and when the charging current or the discharging current appears in the connecting loop, the battery voltage sampled in advance is regarded as the battery voltage at two ends of the battery assembly when the charging current or the discharging current starts to flow through the battery assembly, and the battery electric quantity of the battery assembly is accurately judged according to the battery voltage. Fig. 1 is a schematic structural diagram of a battery power detection circuit according to an embodiment of the present utility model. Referring to fig. 1, the battery level detection circuit 10 includes: a switching module 130, a protection module 120, a detection module 150, a voltage storage module 110, and an electricity meter 140.

The switch module 130 is connected in series in a connection loop of the battery assembly 20 and the charge-discharge assembly 30; the switch module 130 includes a first connection terminal P1, a second connection terminal P2, and a switch control terminal P3; the first connection terminal P1 is electrically connected to the battery assembly 20, and the second connection terminal P2 is electrically connected to the charge/discharge assembly 30. The protection module 120 is electrically connected to the battery assembly 20 and the switch control terminal P3, and the protection module 120 is used for controlling the on state of the switch module 130 according to the operation state of the battery assembly 20. The voltage storage module 110 is connected between the positive and negative terminals of the battery assembly 20; the voltage storage module 110 is used to collect and store the battery voltage of the battery assembly 20. The fuel gauge 140 is connected in parallel to both ends of the charge and discharge assembly 30 and is electrically connected to the output terminal of the voltage storage module 110. The detection end of the detection module 150 is electrically connected to the second connection end P2, and the output end of the detection module 150 is electrically connected to the voltage storage module 110 and/or the fuel gauge 140. The detection module 150 is configured to detect a potential jump of the second connection terminal P2, so that the electricity meter 140 calculates the battery power of the battery assembly 20 when the potential jump of the second connection terminal P2 is calculated according to the battery voltage stored in the voltage storage module 110 before the potential jump of the second connection terminal P2.

In fig. 1, the battery assembly 20 includes a cell E and a parasitic resistance R0 connected in series between the positive and negative terminals of the battery assembly 20, and the parasitic resistance R0 of the cell is represented by a resistance connected in series with the cell E, including, for example, a cell internal resistance and the like. The battery cell E can be formed by a lithium battery, and can be a single battery or a series-parallel structure of a plurality of batteries. The charge and discharge assembly 30 may be understood as a generic term for a charger and a load that may be connected in parallel to the positive power output BAT + and the negative power output BAT-. When the charger is connected with the positive output end BAT+ of the power supply and the negative output end BAT-of the power supply, a connection loop formed by the charger and the battery assembly 20 is a charging loop; when the load is connected to the positive power supply output terminal bat+ and the negative power supply output terminal BAT-, the connection circuit formed by the load and the battery pack 20 is a discharge circuit. In the battery detection circuit 10, each functional module may be powered by the battery assembly 20.

The on state of the switch module 130 determines whether the battery assembly 20 is in communication with the charge/discharge assembly 30. When the switch module 130 is turned on, the connection loop forms a path, and current exists. Illustratively, the switch module 130 may be composed of controllable switching devices such as transistors, relays, or analog switches, and necessary peripheral circuits thereof.

The protection module 120 generates a switching control signal according to the operation state of the battery assembly 20 to control whether the connection loop is connected. The operation state of the battery assembly 20 may include whether the state quantities of the battery assembly 20 such as voltage, current, and temperature are normal. For example, the protection module 120 may include a series of logic circuits therein and access a series of reference state signals, such as access to a discharge current threshold, a charge current threshold, an overdischarge voltage threshold, an overcharge voltage threshold, a short circuit current threshold, an operating temperature threshold, and the like. The actual state signal of the connection loop in the actual operation process is compared with the corresponding reference state signal through the logic circuit, when any comparison result indicates abnormal operation, the protection is triggered, the protection module 120 sets the switch control signal to be a cut-off potential, and the switch module 130 is controlled to be turned off, so that the electronic equipment is prevented from continuously operating in an abnormal state. And, the protection module 120 may be configured to control the switch module 130 to be turned on after a preset time interval, and determine whether each comparison result is abnormal again, and if the abnormality is eliminated, may control the switch module 130 to remain turned on. Alternatively, the protection module 120 may be further configured to lock the off state of the switch module 130 when the switch module 130 is turned off in an abnormal state until the lock is released when the charger is again turned on. The protection module 120 may employ any lithium battery protection structure and function known in the art, and is not limited herein.

Illustratively, when the battery assembly 20 is in a normal operation state, the protection module 120 outputs a conduction potential (e.g., a high potential), and the control switch module 130 is turned on to short the connection between the first connection terminal P1 and the second connection terminal P2, so that the battery voltage of the battery assembly 20 can be normally provided to the subsequent fuel gauge 140 and the charge/discharge assembly 30 to enable the fuel gauge 140 and the charge/discharge assembly 30 to operate normally. When the battery voltage is lower than the over-discharge protection voltage threshold, the protection module 120 enters an over-discharge protection mode, outputs a cut-off potential (for example, the output voltage is zero), and controls the switch module 130 to be turned off, so that the electricity meter 140 and the charge-discharge assembly 30 are cut off from being powered, and the electricity meter 140 and the charge-discharge assembly 30 cannot work normally. Alternatively, when the protection module 120 receives a shipping mode on command (e.g., provided by other control modules in the electronic device), it also outputs a cutoff potential (e.g., zero output voltage), and the control switch module 130 is turned off, so that the fuel gauge 140 and the charge and discharge assembly 30 cannot operate normally.

Illustratively, the fuel gauge 140 is connected between a positive power output BAT+ and a negative power output BAT-. The electricity meter 140 may include an electricity calculation unit and a display unit for calculating the battery electricity from the battery voltage and displaying the battery electricity, respectively. The electricity meter 140 may further include a memory for storing a correspondence relationship between the battery voltage and the battery power of the battery assembly 20, for example, in the form of a relationship curve, a table, or a specific functional relation such as an empirical function, so that the power calculation unit performs the battery power calculation. It should be noted that, when the switch module 130 is turned off, no current flows in the connection loop, and the battery voltage at the two ends of the battery assembly 20 is the voltage on the actual battery cell E; when the switch module 130 is turned on and a charging current or a discharging current starts to occur in the connection loop, the battery voltage across the battery assembly 20 includes an interference amount (or referred to as a sudden change amount) caused by the parasitic resistance R0. Then, at the moment the switch module 130 is turned on, if the electricity meter 140 calculates the battery power according to the abrupt battery voltage, the calculation result is inaccurate. To solve the above problems, the embodiment of the present utility model introduces the voltage storage module 110.

Illustratively, components such as a capacitor or an analog-to-digital converter may be included in the voltage storage module 110 to facilitate capturing and storing the battery voltage of the battery assembly 20. The voltage storage module 110 is directly connected between the positive terminal and the negative terminal of the battery assembly 20, the working state of the voltage storage module 110 is not affected by the on state of the switch module 130, and the voltage storage module 110 can normally perform voltage collection no matter the switch module 130 is turned on or off. Then, the voltage storage module 110 can collect the voltage on the actual battery cell E when the switch module 130 is turned off, which is equivalent to recording the accurate battery voltage in advance before the switch module 130 is turned on, and provides a basis for accurately calculating the battery power.

The present embodiment further incorporates a detection module 150 to determine the on-time of the switching module 130, and thus the battery voltage used by the fuel gauge 140 to accurately calculate the battery charge. Specifically, the switch module 130 is connected to the negative terminal of the battery assembly and the negative terminal of the charge-discharge assembly (i.e., the negative output terminal BAT-) of the power supply, and the switch module 130 is turned on after being connected to the charger. When the switch module 130 is turned off due to an abnormal operation state of the battery assembly 20 or due to the shipment mode being entered, the second connection terminal P2 of the switch module 130 is connected to the positive terminal of the battery assembly 20 through the fuel gauge 140 or the partial charge and discharge assembly 30 still connected in the loop, and its potential is close to the high potential outputted from the positive terminal of the battery assembly 20. After the switch module 130 is turned off, when another charge-discharge component, such as a charger, is connected between the positive output terminal bat+ and the negative output terminal BAT-, the potential of the second connection terminal P2 is pulled down to a low potential (e.g., 0 voltage or negative voltage); and when the protection module 120 detects that the charger is connected, the switch module 130 is controlled to be turned on, the system is activated, and the second connection terminal P2 is kept at a low potential. The circuit operation process of the switch module 130 when turned on after the load is connected is similar to that of the charger, and will not be repeated. Thus, the connection of the charger or the load appears as a potential jump of the second connection terminal P2 in the battery level detection circuit 10.

The detection module 150 is configured to detect the above-mentioned potential jump process of the second connection terminal P2, and the time when the potential jump of the second connection terminal P2 occurs may be considered as the access time of the charger or the load, or may be considered as the switching time when the switch module 130 changes from the off state to the on state, that is, the time when the current starts to occur in the connection loop. Then, according to the above analysis, before the potential jump of the second connection terminal P2, the battery voltage at the two ends of the battery assembly 20 is the accurate battery cell voltage, and when the potential jump of the second connection terminal P2 occurs, the battery voltage at the two ends of the battery assembly 20 is inaccurate due to the occurrence of the current. Therefore, based on the detected potential jump time of the second connection terminal P2 by the detection module 150, the fuel gauge 140 can calculate the battery power of the battery assembly 20 during the potential jump according to the battery voltage stored in the voltage storage module 110 before the potential jump, so as to obtain an accurate battery power. Specifically, the detection module 150 may transmit the battery voltage stored before the potential jump to the fuel gauge 140 by controlling the voltage storage module 110, so that the fuel gauge 140 calculates the battery power according to the transmitted battery voltage; and/or directly control the fuel gauge 140 to calculate the battery charge from the stored battery voltage transmitted from the voltage storage module 110 before the potential jump.

In the battery power detection circuit provided by the embodiment of the utility model, a switch module 130, a protection module 120, a detection module 150, a voltage storage module 110 and a fuel gauge 140 are provided. By disposing the voltage storage module 110 between the positive and negative terminals of the battery assembly 20, the voltage storage module 110 can collect the voltages at the two terminals of the battery assembly 20 when the switch module 130 is turned off, so as to accurately represent the battery voltage of the battery cell E. The detection module 150 determines the time when other charge and discharge components are connected to the circuit after the switch module 130 is disconnected, or determines the time when the protection module 120 controls the switch module 130 to be turned on again, by detecting the potential jump of the second connection terminal P2 of the switch module 130. With the time of the potential jump of the second connection terminal P2 as a limit, the voltage storage module 110 acquires an accurate battery voltage before the potential jump, and the battery voltage can be regarded as the accurate battery voltage of the battery assembly 20 at the moment of the potential jump. Therefore, the electricity meter 140 can accurately calculate the battery power of the battery assembly 20 during the potential jump according to the battery voltage stored in the voltage storage module 110 before the potential jump, so as to avoid the deviation of the battery power calculation result caused by the abrupt change of the battery voltage measurement value due to the current in the connection loop and the parasitic resistance R0 during the potential jump. In summary, compared with the prior art, by providing the voltage storage module 110, the embodiment of the utility model stores the accurate battery voltage of the battery assembly 20 in advance before the switch module 130 is turned on, and calculates the battery power by using the battery voltage stored in advance, the accuracy of battery power detection can be effectively improved.

Based on the above embodiments, optionally, the battery power calculated by the on state of the switch module 130 may be used as the initial power, and after a preset time (for example, several seconds) passes after the on state of the switch module 130, the control fuel gauge 140 corrects and adjusts the initial power according to the real-time voltage of the battery assembly 20, so that the calculation result of the battery power is more accurate, and the calculation result of the battery power follows the actual state change of the battery assembly 20 in the charging and discharging processes. The setting is equivalent to that in the preset time after the switch module 130 is turned on, the initial electric quantity is adopted as the battery electric quantity calculation result of the battery assembly 20, after the preset time, the calculation result of the battery electric quantity is enabled to follow the actual state change of the battery assembly, the influence of the battery voltage mutation of the battery assembly 20 on the electric quantity calculation result when the switch module 130 is turned on can be avoided, the electric quantity calculation result accords with the actual change condition, and the accuracy of the battery electric quantity calculation is further ensured.

Fig. 2 is a schematic structural diagram of a voltage storage module according to an embodiment of the utility model. Referring to fig. 2, in one embodiment, optionally, the voltage storage module 110 includes: a pulse generation unit 111 and a memory unit 112.

The pulse generating unit 111 is electrically connected to the control terminal of the memory unit 112, and the pulse generating unit 111 is configured to generate a pulse signal, where the pulse signal includes a first potential and a second potential. Specifically, the pulse signal may include a first potential maintaining phase and a second potential maintaining phase that alternately occur, where the first potential and the second potential are different, one is a high potential, and the other is a low potential. The first terminal of the memory cell 112 is electrically connected to the positive terminal of the battery assembly 20, the second terminal of the memory cell 112 is electrically connected to the negative terminal of the battery assembly 20, and the output terminal of the memory cell 112 serves as the output terminal VDD1 of the voltage storage module 110. The storage unit 112 is configured to store and output the current battery voltage of the battery assembly 20 when the pulse signal is at the first potential, that is, the potential of the output terminal VDD1 at this stage varies according to the potential variation of the positive terminal of the battery assembly 20. And, the memory unit 112 is configured to maintain and output the battery voltage output by the memory unit 112 when the pulse signal is at the second potential, that is, the potential of the output terminal VDD1 is maintained at the potential output in the previous first potential maintaining stage, so as not to follow the potential variation of the positive terminal of the battery assembly 20. Illustratively, the pulse generating unit 111 may include a logic circuit or a control chip to generate the pulse signal; the memory unit 112 may employ any controllable memory element, such as an analog-to-digital converter, a memory chip, and the like.

Based on the above embodiments, optionally, when the detection module 150 detects the potential jump of the second connection terminal P2, the operation state of the voltage storage module 110 and/or the operation state of the fuel gauge 140 may be controlled to finally control the fuel gauge 140 to calculate the battery power by using the battery voltage before the potential jump. Several of these embodiments are described below.

Fig. 3 is a schematic diagram of another battery power detection circuit according to an embodiment of the present utility model. Referring to FIG. 3, in one embodiment, the output of the detection module 150 is optionally electrically connected to the fuel gauge 140. In this case, as shown in fig. 4, the voltage storage module 110 may be configured such that the pulse generating unit 111 may directly generate the pulse signal in which the first potential and the second potential are alternately output at the preset frequency without the need of the control signal, so as to control the storage unit 112 to update the battery voltage output by the storage unit 112 according to the potential of the positive terminal of the battery assembly 20 at the preset frequency. Illustratively, in the pulse signal, the sustain time of the first potential may be several tens of milliseconds and the sustain time of the second potential may be several seconds.

The fuel gauge 140 may include a memory for storing the battery voltage output from the storage unit 112, for example, storing the battery voltage output from the storage unit 112 in real time, or storing the battery voltage output from the storage unit 112 only in the first potential maintaining stage of the pulse signal. The detection module 150 is configured to generate a second jump control signal according to the potential jump of the second connection terminal P2, so as to control the fuel gauge 140 to calculate the battery power of the battery assembly 20 during the potential jump of the second connection terminal P2 according to the battery voltage stored in the memory before the potential jump of the second connection terminal P2, specifically, the battery voltage output by the storage unit 112 when the last first potential maintaining stage in the disconnection period of the switch module 130 is completed.

In this embodiment, the detection module 150 directly controls the operating state of the fuel gauge 140 to achieve accurate battery power calculation. And, the manner of access to the charger 310 and the load 320 is exemplarily shown in fig. 3.

Fig. 5 is a schematic structural diagram of another battery power detection circuit according to an embodiment of the present utility model. Referring to fig. 5, in another embodiment, optionally, an output terminal of the detection module 150 is electrically connected to a control terminal of the pulse generation unit 111. In this case, the structure of the voltage storage module 110 may be seen in fig. 6, and the pulse generating unit 111 includes a control terminal. The detection module 150 is configured to generate a first transition control signal SC according to the potential transition of the second connection terminal P2, and when the pulse generating unit 111 is connected to the first transition control signal SC, the control pulse signal transitions to a second potential, and after the second potential is maintained for a preset period of time, the control pulse signal transitions back to the first potential. When the first transition control signal SC is not connected, the pulse generating unit 111 may maintain the first potential or alternately output the first potential and the second potential according to a preset frequency. In this embodiment, when the potential of the second connection terminal P2 jumps, the pulse signal jumps to the second potential, so that the memory unit 112 maintains and outputs the battery voltage collected in the previous first potential maintaining stage, i.e. the battery voltage before the potential jump, and in the second potential maintaining stage, even if the potential of the positive terminal of the battery assembly 20 changes, the voltage output by the memory unit 112 remains unchanged. Accordingly, the electricity meter 140 may calculate the battery level of the battery assembly 20 from the battery voltage currently output by the storage unit 112.

In this embodiment, the detection module 150 controls the operating state of the voltage storage module 110 to implement accurate battery power calculation.

With continued reference to FIG. 1, in yet another embodiment, optionally, the fuel gauge 140 itself may be provided with the capability of capturing voltage in real time, and then the detection module 150 may be electrically connected to the fuel gauge 140 and the voltage storage module 110, respectively. At the time of the potential jump of the second connection terminal P2, the detection module 150 may control the pulse generating unit 111 to output the second potential, and control the fuel gauge 140 to calculate the battery power according to the battery voltage transmitted from the storage unit 112, so as to implement accurate power calculation.

In addition to the above embodiments, the memory unit 112 may have various structures, and will be described below.

With continued reference to fig. 4 and 6, in one embodiment, the memory cell 112 optionally includes a capacitor C1 and a switch K1; the control end of the switch K1 is used as the control end of the memory unit 112, and the first end of the switch K1 is used as the first end of the memory unit 112; the second end of the switch K1 is electrically connected with the first end of the capacitor C1 and is used as an output end of the memory unit 112; the second terminal of the capacitor C1 serves as the second terminal of the memory cell 112. Illustratively, the switch K1 may be a controllable switch such as a transistor or a relay. In the present embodiment, the pulse generating unit 111 can control whether the battery voltage outputted from the output terminal VDD1 of the voltage storing unit follows the positive terminal potential variation of the battery pack 20 by controlling the on state of the switch K1. Illustratively, the control switch K1 is turned on when the pulse signal is at the first potential, and the control switch K1 is turned off when the pulse signal is at the second potential.

The absolute value of the charge-discharge current of the small-capacity battery system is usually not large, generally only a few uA to tens mA, if the current of 1mA is to be sampled, the voltage flowing through the sampling resistor is only 10uV when the sampling resistor is at 10mΩ, and if an analog-digital converter is adopted, a high-precision analog-digital converter is required, so that the cost is greatly increased. In the embodiment, the switch K1 and the capacitor C1 form the memory cell 112, so that the memory cell 112 has low cost, low power consumption and small occupied circuit area.

Fig. 7 is a schematic structural diagram of another voltage storage module according to an embodiment of the utility model. Referring to fig. 7, in another embodiment, the storage unit 112 optionally includes an analog-to-digital converter ADC, where a control terminal of the analog-to-digital converter ADC is used as a control terminal of the storage unit 112, a first terminal of the analog-to-digital converter ADC is used as a first terminal of the storage unit 112, a second terminal of the analog-to-digital converter ADC is used as a second terminal of the storage unit 112, and an output terminal of the analog-to-digital converter ADC is used as an output terminal of the storage unit 112.

In this embodiment, the ADC is used as the storage unit 112, and the pulse signal can directly control the working state of the ADC without setting the switch K1. When the pulse signal is at the first potential, the analog-to-digital converter ADC converts the analog voltage signal into a digital signal in real time and transmits the digital signal to the fuel gauge. When the pulse signal is at the second potential, the ADC stops converting, and the output of the previous first potential maintaining stage can be maintained. The peripheral circuit of the ADC is simple in structure, and the ADC may be set separately or integrated in a basic protection circuit where the protection module 120 is located.

In practical applications, the specific structure of the storage unit 112 may be set according to the needs of the user.

The switch module 130 may be constructed in various ways based on the above embodiments, and several of them will be described below.

Referring to fig. 3, 5 and 8, in one embodiment, optionally, the switch module 130 includes: a transistor NM0; the control electrode of the transistor NM0 is electrically connected to the switch control terminal, the first electrode of the transistor NM0 is electrically connected to the first connection terminal P1, and the second electrode of the transistor NM0 is electrically connected to the second connection terminal P2. The switching state of the transistor NM0 is the on state of the switch module 130. The transistor NM0 may be a MOS transistor, for example.

Fig. 9 is a schematic structural diagram of another battery level detection circuit according to an embodiment of the present utility model. Referring to fig. 9, in another embodiment, the switch control terminal optionally includes a first control sub-terminal and a second control sub-terminal. The switching module 130 includes: a first MOS transistor NM1 and a second MOS transistor NM2. The grid electrode of the first MOS tube NM1 is electrically connected with the first control sub-end, the source electrode of the first MOS tube NM1 is electrically connected with the first connecting end P1, the drain electrode of the first MOS tube NM1 is electrically connected with the drain electrode of the second MOS tube NM2, the grid electrode of the second MOS tube NM2 is electrically connected with the second control sub-end, and the source electrode of the second MOS tube NM2 is electrically connected with the second connecting end P2.

In this embodiment, the switch module 130 is formed by two MOS transistors with the same channel type connected in reverse series, and the body diodes of the two MOS transistors are connected in reverse series, wherein one MOS transistor is a charge control MOS transistor, and blocks the charging current through the body diode when the charge is abnormal, and the other MOS transistor is a discharge control MOS transistor, and blocks the discharging current through the body diode when the discharge is abnormal. When both MOS transistors are on, the switch module 130 is on.

With continued reference to fig. 3, in one embodiment, optionally, a lithium battery protection circuit 40 is included in the electronic device, and the protection module 120 may be integrated into the lithium battery protection circuit 40. Illustratively, the lithium battery protection circuit 40 includes a power supply terminal VDD, a ground terminal GND, a system terminal VM, and a shipping control terminal SM. The power terminal VDD is connected to the positive terminal of the battery assembly 20, the ground terminal GND is connected to the negative terminal of the battery assembly 20, and the protection module 120 obtains a system operation state through the system terminal VM and obtains a shipping mode control signal through the shipping control terminal SM. The lithium-ion protection circuit 40 may be an integrated circuit disposed on a wafer.

With continued reference to fig. 3, the switch module 130 and the protection module 120 may be integrated in the lithium battery protection circuit 40 and formed on the same wafer, as an alternative to the above embodiments.

With continued reference to fig. 5, in one embodiment, alternatively, the detection module 150 and the protection module 120 may be integrated in the lithium-ion protection circuit 40 and formed on the same wafer, and both form the basic protection circuit 410.

With continued reference to fig. 8, in one embodiment, the voltage storage module 110 is optionally integrated with the protection module (or the base protection circuit 410) in the lithium-ion protection circuit 40, formed on the same wafer. Then, the output terminal VDD1 of the voltage storage module 110 can also be disposed in the lithium battery protection circuit 40. Illustratively, the output terminal VDD1 of the voltage storage module 110 and the shipping control terminal SM may be used in combination.

The above embodiments are given by way of example, but not by way of limitation, of the integration of functional modules into a lithium battery protection circuit. In other embodiments, the voltage storage module 110 may be disposed separately from the protection module 120, and disposed on different wafers. The detection module 150 may be disposed separately from the protection module 120, and disposed on different wafers. The detection module 150 may also be provided integrally with the voltage storage module 110 or the electricity meter. As shown in fig. 9, the switch module 130 may be disposed separately from the protection module 120 and disposed on different wafers. In this case, the lithium battery protection circuit 40 is not provided in the electronic device, but the lithium battery protection control circuit 50 and the switching module 130 are provided, respectively. The lithium battery protection control circuit 50 may include other functional modules of the lithium battery protection circuit 40 except for the switch module 130, and the specific structure is not described again.

In the above embodiments, the first connection terminal P1 is electrically connected to the negative terminal of the battery assembly 20, the second connection terminal P2 is electrically connected to the negative terminal of the charge/discharge assembly 30, and the ground terminal GND may be multiplexed to the first connection terminal P1 and the system terminal VM may be multiplexed to the second connection terminal P2, but the present utility model is not limited thereto. In other embodiments, as shown in fig. 10, the first connection terminal P1 may be further configured to be electrically connected to the positive terminal of the battery assembly 20, the second connection terminal P2 may be electrically connected to the positive terminal of the charge/discharge assembly 30, and the power source terminal VDD may be multiplexed to the first connection terminal P1 and still be multiplexed to the second connection terminal P2 by the system terminal VM. The switch module 130 may still adopt the structure of any of the above embodiments. Preferably, when the switch module 130 is connected between the two negative terminals, the transistor in the switch module 130 is an N-type transistor (e.g., NM 0); when the switch module 130 is connected between the two positive terminals, the transistors in the switch module 130 are P-type transistors (e.g., PM 0) so as to control the switching state of the switch module 130.

The embodiment of the utility model also provides electronic equipment which comprises a battery assembly and the battery electric quantity detection circuit provided by any embodiment of the utility model, and has corresponding beneficial effects. In addition, the electronic device may be provided with a charge/discharge unit such as an electric load connected to the battery unit and a charger for charging the battery unit. The electronic device may be an intelligent wearable device such as a smart watch or a true wireless bluetooth headset, or may be a portable electronic device such as an electronic cigarette, a mobile power supply, and a smart toy.

In the embodiments of the battery power detection circuit, specific descriptions of the structure of the electronic device exist, and these structures may be considered as the constituent structures of the electronic device provided in the embodiments of the present utility model, and the repetitive contents will not be described herein.

It should be appreciated that various forms of the flows shown above may be used to reorder, add, or delete steps. For example, the steps described in the present utility model may be executed in parallel, sequentially, or in a different order, as long as the desired results of the technical solution of the present utility model can be achieved, and the present utility model is not limited herein.

The above embodiments do not limit the scope of the present utility model. It will be apparent to those skilled in the art that various modifications, combinations, sub-combinations and alternatives are possible, depending on design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included in the scope of the present utility model.

Claims

1. A battery level detection circuit, comprising: the device comprises a switch module, a protection module, a detection module, a voltage storage module and an electricity meter;

2. The battery level detection circuit of claim 1, wherein the voltage storage module comprises: a pulse generating unit and a memory unit;

3. The battery power detection circuit according to claim 2, wherein an output end of the detection module is electrically connected to a control end of the pulse generation unit, the detection module is configured to generate a first jump control signal according to a potential jump of the second connection end, so that the pulse generation unit controls the pulse signal to jump to the second potential, and the electricity meter is configured to calculate the battery power of the battery assembly according to the battery voltage currently output by the storage unit.

4. The battery power detection circuit according to claim 2, wherein an output terminal of the detection module is electrically connected to the power meter, the pulse generation unit is configured to generate pulse signals that the first potential and the second potential are alternately output at a preset frequency, and the power meter includes a memory configured to store the battery voltage output by the storage unit; the detection module is used for generating a second jump control signal according to the potential jump of the second connection end so as to control the fuel gauge to calculate the battery electric quantity of the battery assembly when the potential jump of the second connection end is carried out according to the battery voltage stored by the memory before the potential jump of the second connection end.

5. The battery level detection circuit of claim 2, wherein the storage unit comprises a capacitor and a switch; the control end of the switch is used as the control end of the storage unit, and the first end of the switch is used as the first end of the storage unit; the second end of the switch is electrically connected with the first end of the capacitor and is used as the output end of the storage unit; the second end of the capacitor is used as the second end of the storage unit;

Or alternatively, the process may be performed,

6. The battery charge detection circuit of claim 1, wherein the first connection terminal is electrically connected to the positive terminal of the battery assembly and the second connection terminal is electrically connected to the positive terminal of the charge-discharge assembly;

or alternatively, the process may be performed,

7. The battery level detection circuit of claim 1 or 6, wherein the switch module comprises: a transistor; the control electrode of the transistor is electrically connected with the switch control end, the first electrode of the transistor is electrically connected with the first connecting end, and the second electrode of the transistor is electrically connected with the second connecting end;

or alternatively, the process may be performed,

8. The battery power detection circuit of claim 1, wherein the voltage storage module and the protection module are integrated on a same wafer, or the voltage storage module and the protection module are disposed on different wafers, respectively.

9. The battery power detection circuit of claim 1, wherein the detection module and the protection module are integrated on a same wafer, or the detection module and the protection module are respectively disposed on different wafers;

10. An electronic device, comprising: a battery assembly and a battery charge detection circuit as claimed in any one of claims 1 to 9.