CN115051428A - Battery protection chip and battery device - Google Patents

Abstract

The application relates to a battery protection chip and a battery device, including a signal generation circuit, a detection circuit, a logic drive circuit and a control switch. The signal generation circuit generates a detection signal and sends it to the detection circuit and the logic drive circuit; the number of detection signals is more than two , used to time-division control the detection circuit to enter the detection state corresponding to the detection signal; when the detection circuit receives the detection signal, it enters the detection state corresponding to the detection signal, and when it is judged that the working state of the battery is not normal, it outputs an indication signal to Logic drive circuit; the logic drive circuit generates a drive signal according to the detection signal and the indication signal, drives the control switch to switch the open and close states, and cuts off or conducts the charging circuit or the discharging circuit of the battery and the external device, because the detection circuit only detects the corresponding signal at the same time. The detection state is in a working state, and other detection states do not need to continuously consume battery power, which solves the problem of high power consumption of the current battery protection chip.

Description

Battery protection chip and battery device

technical field

The present application relates to the technical field of lithium battery protection, and in particular, to a battery protection chip and a battery device.

Background technique

With the development of electronic technology, lithium batteries have entered a large-scale practical stage and become an essential power source for various devices. Among them, because the battery capacity can be miniaturized, it is especially widely used in the field where the size of the device is limited. For example, smart wearable devices such as smart watches, bracelets, and Bluetooth headsets, the capacity of lithium batteries may be only tens of mAh, or even as low as several mAh.

At present, a battery protection chip is usually used to monitor and protect the charging and discharging process of lithium batteries, and when abnormal battery charging and discharging occurs, the connection between the battery and external devices is cut off in time. However, the traditional detection method for abnormal charging and discharging is to use real-time detection, that is, the corresponding detection circuit is always in the working state during the charging and discharging process, and the battery power is continuously consumed, resulting in the problem of high power consumption, which cannot meet the needs of various smart wearable devices. demand for small-capacity batteries.

SUMMARY OF THE INVENTION

Based on this, it is necessary to provide a battery protection chip and a battery device to solve the problem of high power consumption of the current battery protection chip.

A battery protection chip includes a signal generation circuit, a detection circuit, a logic drive circuit and a control switch, the signal generation circuit is connected with the detection circuit and the logic drive circuit, and the detection circuit is connected with the logic drive circuit and a battery , the control switch is arranged in the charging and discharging circuit of the battery and the external device, and is connected with the logic driving circuit;

The signal generating circuit is used for generating a detection signal, and sending the detection signal to the detection circuit and the logic driving circuit; the number of the detection signal is more than two, which is used for time-sharing control of the detection circuit enter the detection state corresponding to the detection signal;

When the detection circuit receives the detection signal, it enters the detection state corresponding to the detection signal to detect the working parameters of the battery, and outputs an indication signal to the logic driving circuit according to the working parameters of the battery;

The logic drive circuit generates a drive signal according to the detection signal and the instruction signal; the drive signal is used to drive the control switch to switch between on and off states.

In one embodiment, the battery protection chip further includes a reference circuit, the reference circuit is connected to the signal generating circuit and the detection circuit;

The signal generating circuit is further configured to generate a reference enable signal according to the detection signal, and send the reference enable signal to the reference circuit;

The reference circuit generates reference parameters to the detection circuit when receiving the reference enable signal.

In one embodiment, the detection signal includes an overcharge detection signal, an overdischarge detection signal, a charge overcurrent detection signal and a discharge overcurrent detection signal; the detection circuit includes a charge and discharge overcurrent detection circuit and an overcharge and overdischarge detection circuit. A detection circuit, the charge and discharge overcurrent detection circuit is connected to the signal generation circuit, the reference circuit and the logic drive circuit, and the overcharge and overdischarge detection circuit is connected to the signal generation circuit, the reference circuit, the the battery and the logic drive circuit;

The charging and discharging overcurrent detection circuit is configured to detect the current parameter of the battery when receiving the charging overcurrent detection signal or the discharging overcurrent detection signal, and output an overcurrent indication according to the current parameter of the battery a signal to the logic drive circuit;

The overcharge and overdischarge detection circuit is used to detect the voltage parameter of the battery when receiving the overcharge detection signal or the overdischarge detection signal, and output an overvoltage indication signal to the battery according to the voltage parameter of the battery. the logic drive circuit.

In one embodiment, the overcharge and overdischarge detection circuit includes a voltage divider circuit and a voltage detection circuit, the voltage divider circuit is connected to the battery, the signal generation circuit and the voltage detection circuit, the voltage detection circuit The circuit connects the signal generating circuit, the reference circuit and the logic driving circuit.

In one embodiment, the voltage detection circuit includes a first data selector, a voltage comparator and a first logic OR gate, and the first data selector is connected to the voltage dividing circuit, the signal generating circuit and the The voltage comparator is connected to the reference circuit, the first logical OR gate and the logic driving circuit, and the first logical OR gate is connected to the signal generating circuit.

In one embodiment, the charge-discharge overcurrent detection circuit includes a first switch, a second switch, a first resistor, a second resistor, a current comparator and a second logic OR gate, the first switch and the The control part of the second switch is connected to the signal generating circuit, the first switch is connected in series with the connection line between the reference circuit and the first end of the current comparator, and the second switch is connected in series with the reference A connection line between the circuit and the second end of the current comparator, the first end of the current comparator is also grounded through a first resistor, and the second end of the current comparator is also connected to the charging and discharging loop through a second resistor The negative terminal of the second logic OR gate is connected to the signal generating circuit and the third terminal of the current comparator, and the fourth terminal of the current comparator is connected to the logic driving circuit.

In one embodiment, the logic driving circuit includes a voltage comparator output circuit, a current comparator output circuit and a driving output circuit, the voltage comparator output circuit is connected to the signal generating circuit, the voltage comparator and the The drive output circuit, the current comparator output circuit is connected to the signal generating circuit, the current comparator and the drive output circuit, and the drive output circuit is connected to the control switch.

In one embodiment, when the control switch is a single power transistor structure, the logic driving circuit further includes a substrate selection circuit, and the substrate selection circuit connects the driving output circuit and the control switch.

In one embodiment, the signal generating circuit includes a clock circuit and a state machine, the clock circuit is connected to the state machine, and the state machine is connected to the detection circuit and the logic driving circuit.

In one of the embodiments, a battery device is provided, comprising a battery and the above-mentioned battery protection chip, and the battery is connected to the battery protection chip.

The above-mentioned battery protection chip and battery device output a plurality of detection signals through the signal generation circuit to control the detection circuit to enter the detection state corresponding to the detection signal in time division, and the detection circuit detects and outputs an indication signal to the logic driving circuit according to the working parameters of the battery, and the logic driving circuit Then generate a driving signal according to the detection signal and the indication signal, and drive the control switch to switch the on and off state to realize the battery protection function. Since the detection circuit only detects the corresponding detection state of the signal at the same time, it is in the working state, and all the detection states do not need to continuously consume battery power. The problem of high power consumption of the current battery protection chip is solved.

Description of drawings

1 is a system block diagram of a battery protection chip in an embodiment;

2 is a structural diagram of a battery device in an embodiment;

FIG. 3 is a timing diagram of a detection signal in an embodiment;

4 is a schematic circuit diagram of a voltage detection circuit in an embodiment;

5 is a schematic circuit diagram of a voltage detection circuit in another embodiment;

6 is a schematic circuit diagram of a charge-discharge overcurrent detection circuit in an embodiment;

7 is a schematic circuit diagram of a charge-discharge overcurrent detection circuit in another embodiment;

8 is a schematic structural diagram of a current comparator in an embodiment;

FIG. 9 is a schematic diagram of turning off the charging circuit in an embodiment;

FIG. 10 is a schematic diagram of turning off the discharge circuit in an embodiment.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present application more clearly understood, the present application will be described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, but not to limit the present application.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this application belongs. The terms used herein in the specification of the application are for the purpose of describing specific embodiments only, and are not intended to limit the application.

It will be understood that the terms "first", "second", etc. used in this application may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish a first element from another element. For example, a first resistance may be referred to as a second resistance, and similarly, a second resistance may be referred to as a first resistance, without departing from the scope of this application. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

It can be understood that the "connection" in the following embodiments should be understood as "electrical connection", "communication connection", etc. if the connected circuits, modules, units, etc. have electrical signals or data transmission between them.

As used herein, the singular forms "a," "an," and "the/the" can include the plural forms as well, unless the context clearly dictates otherwise. It should also be understood that the terms "comprising/comprising" or "having" etc. designate the presence of stated features, integers, steps, operations, components, parts or combinations thereof, but do not preclude the presence or addition of one or more Possibilities of other features, integers, steps, operations, components, parts or combinations thereof.

As described in the background art, lithium batteries are especially widely used in fields where the volume of equipment is limited due to the feature that the battery capacity can be miniaturized. For example, smart wearable devices such as smart watches, bracelets, and Bluetooth headsets, the capacity of lithium batteries may be only tens of mAh, or even as low as several mAh. In order to ensure the safety of the use process, the battery protection chip is usually used to monitor and protect the charging and discharging process of the lithium battery. However, the traditional detection method for abnormal charging and discharging is to use real-time detection, that is, the corresponding detection circuit is always in the working state during the charging and discharging process, and the battery power is continuously consumed, resulting in the problem of high power consumption, which cannot meet the needs of various smart wearable devices. demand for small-capacity batteries. At the same time, each detection function included in the detection circuit in the prior art also works independently and consumes battery power, which also leads to the problem of high power consumption.

Based on this, in one embodiment, as shown in FIG. 1 , a battery protection chip 100 is provided, including a signal generation circuit 110 , a detection circuit 120 , a logic drive circuit 130 and a control switch 140 , and the signal generation circuit 110 is connected to the detection circuit 120 The logic drive circuit 130 and the detection circuit 120 are connected to the logic drive circuit 130 and the battery 200. The control switch 140 is arranged in the charging and discharging circuit between the battery 200 and the external device, and is connected to the logic drive circuit 130. The signal generating circuit 110 is used to generate detection The detection signal is sent to the detection circuit 120 and the logic drive circuit 130; the number of detection signals is more than two, which is used to time-division control the detection circuit 120 to enter the detection state corresponding to the detection signal; the detection circuit 120 receives the detection signal When it enters the detection state corresponding to the detection signal, the working parameters of the battery are detected, and the indication signal is output to the logic driving circuit 130 according to the working parameters of the battery; the logic driving circuit 130 generates the driving signal according to the detection signal and the indication signal; the driving signal is used for driving control The switch 140 switches the on-off state.

Among them, as shown in FIG. 2 , the battery 200 (Li-battery) includes a total positive terminal B+ and a total negative terminal B-, and the total positive terminal B+ and the total negative terminal B- of the battery 200 pass through the external positive terminal P+ and the external negative terminal respectively. P - to connect with external equipment. The external devices connected to the battery 200 through the two external terminals are not unique. It can be connected to a load to form a discharge loop, and the battery 200 can be used to supply power to the load; it can also be connected to an external charging device to form a charging loop, and the external charging device can be used to charge the battery 200.

The control switch 140 is arranged on the connection line between the total positive terminal B+ of the battery 200 and the external positive terminal P+ or the connection line between the total negative terminal B- and the external negative terminal P-, and is used to control the discharge circuit or the charging circuit of the battery 200 and external equipment. Whether to open. When the control switch 140 is turned on, the battery 200 is connected to the discharge circuit or the charging circuit of the external device, and can be used to supply power to the load or use an external charging device for charging; when the control switch 140 is turned off, the battery 200 is discharged from the external device. The circuit or charging circuit is disconnected, and the load cannot be powered or charged with an external charging device. The number of the control switches 140 is not unique. As shown in FIG. 1 , a single power tube structure control switch 140 may be used to control the battery 200 to be disconnected from the discharge circuit or the charging circuit of the external device. Alternatively, as shown in FIG. 2 , the power tube Q1 and the power tube Q2 of the dual power tube structure may respectively control the battery 200 to be disconnected from the discharge circuit or the charging circuit of the external device.

It can be understood that the battery protection chip 100 uses the signal generating circuit 110 , the detection circuit 120 and the logic driving circuit 130 to output driving signals to control the switch 140 to switch its on and off states, so as to monitor and manage the working state of the battery pack 200 .

Specifically, the signal generating circuit 110 may generate a detection signal for time-divisionally controlling the detection circuit 120 to enter a corresponding detection state. It can be understood that the time-division control detection circuit 120 enters the corresponding detection state, that is, the detection circuit 120 is not continuously in the working state. Only when a detection signal is received, the detection state corresponding to the detection signal is entered, and when no detection signal is received, the detection circuit 120 is in an inactive state. Further, the detection signals are all timing signals, and any signal in the detection signal is in a high-level state, indicating that the detection circuit 120 receives the detection signal and needs to enter the detection state corresponding to the detection signal in the high-level state; all detection signals are low. The level state indicates that the detection circuit 120 does not receive a detection signal, and the detection circuit 120 is in an inactive state. Then, the working time of the detection circuit 120 is the sum of the pulse widths of each detection signal, and the non-working time of the detection circuit 120 is the duration when all the detection signals are in the low level state. Therefore, due to the time-sharing detection technology, the current consumed by the detection circuit during operation is allowed to be a little higher than that in the prior art, so that a larger bandwidth and better noise suppression can be obtained, while most of the detection circuit is in the entire working cycle. The time does not work, so that the average current of the whole cycle can be very small, so that the overall low power consumption of the battery protection chip can be achieved.

The content and quantity of the detection signal need to be determined according to the detection state of the detection circuit 120 . In the embodiments of the present application, the detection circuit 120 includes four detection states that may occur during the charging and discharging process of the battery 200, such as overcharging, overdischarging, charging overcurrent and discharging overcurrent, as examples for explanation. Correspondingly, as shown in FIG. 3 , the signal generating circuit 110 can generate an overcharge detection signal (OV_DET), an overdischarge detection signal (UV_DET), a charge overcurrent detection signal (COC_DET) or a discharge overcurrent detection signal (DOC_DET), and output The detection circuit 120 is controlled to enter the corresponding detection state in time. For example, when OV_DET is high, the detection circuit 120 enters the overcharge detection state; when UV_DET is high, the detection circuit 120 enters the overdischarge detection state; when DOC_DET is high, the detection circuit 120 enters the discharge overcurrent detection state ; When COC_DET is at a high level, the detection circuit 120 enters the charging overcurrent detection state. As can be seen from FIG. 3 , in order to realize the time-division control detection circuit 120 to enter the detection state it possesses, only one of the two or more detection signals generated by the signal generation circuit 110 is in a high level state at the same time. When one of them is in a high-level state, the other detection signals are in a low-level state.

The structure of the signal generating circuit 110 is not unique, and may be implemented by a square wave generator or a controller with a timer and a register. In one embodiment, as shown in FIG. 1 , the signal generating circuit 110 includes a clock circuit and a state machine, the clock circuit is connected to the state machine, and the state machine is connected to the detection circuit and the logic driving circuit. The clock circuit can generate a clock signal with a fixed pulse width and frequency, and input the clock signal to the state machine. The state machine is used for dividing the frequency of the clock signal to generate signals of different frequencies, and then performing combinatorial logic operations on the signals of different frequencies through the state machine to generate detection signals such as OV_DET, UV_DET, DOC_DET, and COC_DET, which are output to the detection circuit 120 .

It can be understood that the pulse widths of all detection signals can be set to be the same, but since different detection states in the detection circuit 120 need to use different time delays to ensure accurate detection, there are corresponding different detection frequencies, and the state machine needs to consider the correspondence between different detection states. The detection frequency is divided by the clock signal. For example, the overcharge protection delay in the overcharge detection state is the longest, and a lower detection frequency can be used, while a slightly higher detection frequency is required for discharge overcurrent detection or charge overcurrent detection. In addition, in order to ensure that the driving of the control switch in the detection state will not cause a large error due to the protection delay, the detection frequency corresponding to the detection signal can be set to a value that is an order of magnitude (about 10 times) smaller than the delay time. . The specific delay time and detection frequency corresponding to the above detection states can be set according to the actual protection chip conditions. As shown in FIG. 3 , taking the four detection states including overcharge, overdischarge, charging overcurrent and discharge overcurrent as an example in this embodiment, the overcharge protection delay corresponding to OV_DET (overcharge detection state) can be set is 100ms, and the detection frequency can be set to 10ms; the over-discharge protection delay corresponding to UV_DET (over-discharge detection state) can be set to 40ms, and the detection frequency can be set to 4ms; DOC_DET (discharge over-current detection state) and COC_DET ( The protection delay corresponding to the charging overcurrent detection state) can be set to 10ms, and the detection frequency can be set to 1ms. Further, it is also necessary to add a time difference to each detection signal on the basis of the above-mentioned respective corresponding detection frequencies, so that only one of the detection signals is in a high level state at the same time. Figure 3 illustrates the variation of the detection signal in two cycles. In this embodiment, the clock circuit and the state machine are used to generate two or more detection signals to alternately cycle, so as to realize the time-division detection of each detection state of the detection circuit.

Further, when the detection circuit 120 receives the detection signal, it enters the detection state corresponding to the detection signal to detect the working parameters of the battery 200, and outputs an indication signal according to the working parameters of the battery. The operating parameters of the battery 200 can be determined according to the detection state of the detection circuit 120. For example, the voltage parameters of the battery can be detected in the detection state of overcharge and overdischarge, and the voltage parameters of the battery can be detected in the detection state of charge overcurrent, discharge overcurrent and discharge short circuit. The current parameters of the battery can be detected below. Correspondingly, the indication signal may also be determined according to the operating parameters of the battery, for example, may include an overvoltage indication signal output according to a voltage parameter, and may also include an overcurrent indication signal output according to a current parameter.

After the logic driving circuit 130 receives the indication signal, it can perform a logic operation according to the detection signal and the indication signal to output a driving signal, and drive the control switch 140 to switch the on-off state. The detection signal is used to determine the current detection state of the detection circuit 120, and the indication signal is used to determine whether there is an error in the current detection state or whether the error is resolved. When it is judged according to the detection signal and the indication signal that the current detection state has an error or the error has not been removed, the output drive signal drives the control switch 140 to be in an off state; when it is judged according to the detection signal and the indication signal that the current detection state is incorrect When there is an error or the error has been eliminated, the output drive signal drives the control switch 140 to be in an on state.

In addition, when the battery 200 is in the normal charging and discharging process, each detection signal alternately controls the detection circuit 120 to enter the corresponding detection state according to the sequence output by the state machine. However, after the logic driving circuit 130 judges that there is an error in the current detection state according to the detection signal and the indication signal, the state machine only outputs the detection signal corresponding to the detection state to the detection circuit 120 until the logic driving circuit 130 according to the detection signal and the indication signal After judging that the current detection state is erroneously removed, each detection signal alternately patrols and controls the detection circuit 120 to enter the corresponding detection state according to the timing output by the state machine to detect the working parameters of the battery 200 .

The above-mentioned battery protection chip outputs a plurality of detection signals through the signal generation circuit to control the detection circuit to enter the detection state corresponding to the detection signals in time division. The signal and the indicator signal generate the driving signal, and the driving control switch switches the on-off state to realize the protection function of the battery. Since the detection circuit only detects the corresponding detection state of the signal at the same time, it is in the working state, and all the detection states do not need to continuously consume the battery power, which solves the problem of the current situation. The problem of high power consumption of the battery protection chip.

In one embodiment, as shown in FIG. 1 , the battery protection chip 100 further includes a reference circuit 150, and the reference circuit 150 is connected to the signal generation circuit 110 and the detection circuit 120; the signal generation circuit 110 is further configured to generate a reference enable signal according to the detection signal , and send the reference enable signal to the reference circuit 150 ; the reference circuit 150 generates reference parameters to the detection circuit 120 when receiving the reference enable signal.

Specifically, the signal generation circuit 110 generates a reference enable signal (EN_REF) and sends it to the reference circuit 150 when any of the generated detection signals is in a high level state, so that the reference circuit 150 generates reference parameters to the detection circuit 120 . The type of the reference parameter may be determined according to the type of the detected operating parameter of the battery, for example, including a reference voltage or a reference current. It can be understood that the reference parameter is a voltage signal or a current signal that does not change with time. Whether the reference voltage or the reference current is specifically sent to the detection circuit 120 may be determined according to the type of the detection signal. For example, when the detection signal is the overcharge detection signal (OV_DET) or the overdischarge detection signal (UV_DET), the reference circuit 150 generates a reference voltage and sends it to the detection circuit 120; when the detection signal is the charge overcurrent detection signal (COC_DET) or the discharge overcurrent detection signal (COC_DET) When the detection signal (DOC_DET) is present, the reference circuit 150 generates a reference current and sends it to the detection circuit 120 . The specific value of the reference voltage or the reference current is not unique, and can be set according to the working parameters of the battery 200 and the protection threshold.

In this embodiment, the reference circuit is controlled by outputting the reference enable signal to send out the reference parameters only during the working time of the detection circuit, which further reduces the power consumption of the battery protection chip.

In one embodiment, the detection signal includes an overcharge detection signal, an overdischarge detection signal, a charge overcurrent detection signal and a discharge overcurrent detection signal; the detection circuit 120 includes a charge and discharge overcurrent detection circuit and an overcharge and overdischarge detection circuit. The discharge overcurrent detection circuit is connected to the signal generation circuit 110 , the reference circuit 150 and the logic drive circuit 130 , and the overcharge and overdischarge detection circuit is connected to the signal generation circuit 110 , the reference circuit 150 , the battery 200 and the logic drive circuit 130 . The charging and discharging overcurrent detection circuit is used to detect the current parameter of the battery when receiving the charging overcurrent detection signal or the discharging overcurrent detection signal, and output the overcurrent indication signal to the logic drive circuit 130 according to the current parameter of the battery; The discharge detection circuit is used to detect the voltage parameter of the battery when receiving the overcharge detection signal or the overdischarge detection signal, and output an overvoltage indication signal to the logic driving circuit 130 according to the voltage parameter of the battery.

In this embodiment, taking the detection circuit 120 including four detection states that may occur during the charging and discharging of the battery 200, including overcharge, overdischarge, charging overcurrent, and discharging overcurrent, as an example, the detection circuit 120 adopts an overcharge overcurrent The discharge detection circuit realizes the multiplexing of the two detection states of overcharge and overdischarge at the same time, and the charge and discharge overcurrent detection circuit is used to realize the multiplexing of the two detection states of charge overcurrent and discharge overcurrent at the same time. Compared with the prior art, four comparison circuits are required to complete four detection states, such as overcharge, overdischarge, charge overcurrent and discharge overcurrent, respectively, which reduces power consumption and saves the area of the chip.

In one embodiment, the overcharge and overdischarge detection circuit includes a voltage divider circuit and a voltage detection circuit, the voltage divider circuit is connected to the battery, the signal generation circuit and the voltage detection circuit, and the voltage detection circuit is connected to the signal generation circuit, the reference circuit and the logic drive circuit.

Specifically, as shown in FIG. 1 and FIG. 2 , the voltage divider is composed of two or more resistors connected in series. One end of the series connection is connected to the total positive terminal B+ of the battery 200 through the VDD terminal of the battery protection chip to obtain the voltage of the battery 200. The other end of the series is connected to ground. When the generated overcharge detection signal (OV_DET) or the overdischarge detection signal (UV_DET) is in a high level state, the signal generation circuit 110 generates an overcharge and overdischarge enable signal (EN_VDD_DIV) and sends it to the voltage divider circuit, so as to divide the voltage The circuit divides the voltage according to the obtained voltage parameters of the battery, and outputs the overcharge judgment voltage division (VDD_DIV_OV) and the overdischarge judgment voltage division (VDD_DIV_UV) to the voltage detection circuit through the common terminal connected in series with the resistors.

The voltage detection circuit is used to obtain the overcharge judgment divided voltage (VDD_DIV_OV) when receiving the overcharge detection signal, and output the overvoltage indication signal according to the overcharge judgment divided voltage (VDD_DIV_OV) and the reference voltage; the voltage detection circuit is also used to When the over-discharge detection signal is received, the over-discharge judgment divided voltage (VDD_DIV_UV) is obtained, and the over-voltage indication signal is output according to the over-discharge judgment divided voltage (VDD_DIV_UV) and the reference voltage.

In one embodiment, as shown in FIG. 4 , the voltage detection circuit includes a first data selector mux2_3, a voltage comparator and a first logical OR gate OR1, and the first data selector mux2_3 is connected to a voltage divider circuit, a signal generating circuit and a voltage The comparator, the voltage comparator is connected to the reference circuit, the first logical OR gate OR1 and the logic driving circuit, and the first logical OR gate is connected to the signal generating circuit.

The output terminal of the first data selector mux2_3 can be connected to the non-inverting terminal or the inverting terminal of the voltage comparator, and the corresponding reference circuit can be connected to the inverting terminal or the non-inverting terminal of the voltage comparator, which can be set according to the actual situation without limitation. . In this embodiment, the output terminal of the first data selector mux2_3 is connected to the non-inverting terminal of the voltage comparator, and the reference circuit is connected to the inverting terminal of the voltage comparator as an example for explanation.

Specifically, the first logical OR gate OR1 is used to receive the overcharge detection signal (OV_DET) and the overdischarge detection signal (UV_DET), and output the voltage comparator according to the overcharge detection signal (OV_DET) and the overdischarge detection signal (UV_DET) to enable Enable signal to control the working state of the voltage comparator. When the overcharge detection signal (OV_DET) or the overdischarge detection signal (UV_DET) is in a high level state, the first logical OR gate OR1 outputs a voltage comparator enable signal to control the voltage comparator to enable operation.

Further, when receiving the overcharge detection signal (OV_DET), the first data selector mux2_3 selects the channel 1 to obtain the overcharge determination voltage divider (VDD_DIV_OV) and outputs it to the non-inverting terminal of the voltage comparator. The voltage comparator compares the voltage divider (VDD_DIV_OV) with the reference voltage (VREF) input by the inverting terminal according to the overcharge judgment, and outputs the overvoltage indication signal, which is further used to output the driving signal to judge whether the current detection state has errors. When the overcharge judgment voltage divider (VDD_DIV_OV) is less than the reference voltage (VREF), the output overvoltage indication signal is low; when the overcharge judgment voltage divider (VDD_DIV_OV) is greater than or equal to the reference voltage (VREF) and the duration is longer than the overcharge When the protection is delayed, the output overvoltage indication signal is high level.

When receiving the over-discharge detection signal (UV_DET), the first data selector mux2_3 selects the channel 2 to obtain the over-discharge determination voltage division (VDD_DIV_UV) and outputs it to the non-inverting terminal of the voltage comparator. The voltage comparator compares the divided voltage (VDD_DIV_UV) with the reference voltage (VREF) input by the inverting terminal according to the over-discharge judgment, and outputs an over-voltage indication signal. When the over-discharge judgment voltage division (VDD_DIV_UV) is greater than the reference voltage (VREF), the output over-voltage indication signal is high; when the over-discharge judgment voltage division (VDD_DIV_UV) is less than or equal to the reference voltage (VREF) and the duration is longer than the over-discharge When the protection is delayed, the output overvoltage indication signal is low level.

In addition, when the voltage detection circuit outputs an overvoltage indication signal, and the logic driving circuit 130 judges that there is an error in the current detection state according to the detection signal and the indication signal, the voltage detection circuit may judge what to do according to whether the load or external charging device is connected. restore the battery to its normal state.

In one embodiment, the voltage divider circuit is further configured to generate the overcharge recovery determination voltage divider (VDD_DIV_OVhys) and the overdischarge recovery determination voltage divider (VDD_DIV_UVhys) according to the voltage of the battery when receiving the overcharge and overdischarge enable signal. As shown in FIG. 5 , the voltage detection circuit further includes an external device detection circuit, a second data selector mux2_1 and a third data selector mux2_2, and the external device detection circuit is connected to the second data selector mux2_1 and the third data selector mux2_2. The two data selectors mux2_1 and the third data selector mux2_2 are both connected to the voltage divider circuit and the first data selector mux2_3. The external device detection circuit can output the load access signal (Loader_IN) to the control terminal of the second data selector mux2_1 when the load is connected, and can also output the charging device access signal (Charger_IN) to the third data selector when the external charging device is connected The control side of the data selector mux2_2. The input terminal of the second data selector mux2_1 is connected to the voltage divider circuit to select and obtain the overcharge judgment voltage divider (VDD_DIV_OV) or the overcharge recovery judgment voltage divider (VDD_DIV_OVhys), and input the selected voltage divider to the channel of the first data selector mux2_3 1. The input terminal of the third data selector mux2_2 is connected to the voltage divider circuit to select and obtain the over-discharge judgment divided voltage (VDD_DIV_UV) or the over-discharge recovery judgment divided voltage (VDD_DIV_UVhys), and input the selected divided voltage to the channel of the first data selector mux2_3 2.

Specifically, after judging that there is an error in the overcharge detection state, two methods can be used to restore to the normal state according to whether the load access signal (Loader_IN) is connected or not. When the load access is detected, the load access signal (Loader_IN) is at high level, and the second data selector mux2_1 selects the channel 1 to obtain the overcharge judgment voltage divider (VDD_DIV_OV) and outputs it to the channel 1 of the first data selector mux2_3. Then, when receiving the overcharge detection signal (OV_DET), the first data selector mux2_3 selects the channel 1 to obtain the overcharge judgment voltage divider (VDD_DIV_OV) and outputs it to the non-inverting terminal of the voltage comparator, and compares the output with the reference voltage (VREF). pressure indication signal. At this time, the threshold for judging whether the working state of the battery can be restored to the normal state and the threshold for whether the battery is in the overcharge state are both the overcharge judgment voltage divider (VDD_DIV_OV), and there is no hysteresis voltage. When no load access is detected, the load access signal (Loader_IN) is at low level, and the second data selector mux2_1 selects the channel 2 to obtain the overcharge recovery judgment voltage division (VDD_DIV_OVhys) and outputs it to the channel of the first data selector mux2_3 1. At this time, the threshold for judging whether the battery operating state can be restored to the normal state becomes the overcharge recovery judgment voltage divider (VDD_DIV_OVhys), which has a hysteresis voltage compared with the overcharge judgment voltage divider (VDD_DIV_OV).

Further, when it is judged that there is an error in the over-discharge detection state, two methods can be used to restore to the normal state according to whether the charging device access signal (Charger_IN) is connected or not. When it is detected that the external charging device is connected, the charging device access signal (Charger_IN) is at a high level, and the third data selector mux2_2 selects the channel 1 to obtain the over-discharge judgment voltage division (VDD_DIV_UV) and outputs it to the first data selector mux2_3. channel 2. Then, when receiving the over-discharge detection signal (UV_DET), the first data selector mux2_3 selects channel 2 to obtain the over-discharge judgment voltage divider (VDD_DIV_UV) and output it to the non-inverting terminal of the voltage comparator, which is compared with the reference voltage (VREF) to judge the output Overvoltage indication signal. At this time, the threshold for judging whether the working state of the battery can be restored to the normal state and the threshold for whether the battery is in the over-discharge state are both the over-discharge judgment voltage division (VDD_DIV_UV), and there is no hysteresis voltage. When the external charging device is not detected, the charging device access signal (Charger_IN) is low level, the third data selector mux2_2 selects the channel 2 to obtain the over-discharge recovery judgment voltage divider (VDD_DIV_UVhys) and outputs it to the first data selector Channel 1 of mux2_3. At this time, the threshold for judging whether the battery operating state can be restored to the normal state becomes the overdischarge recovery judgment voltage divider (VDD_DIV_UVhys), which has a hysteresis voltage compared with the overdischarge judgment voltage divider (VDD_DIV_UV).

Among them, the values of the overcharge judgment voltage divider (VDD_DIV_OV), the overdischarge judgment voltage divider (VDD_DIV_UV), the overcharge recovery judgment voltage divider (VDD_DIV_OVhys) and the overdischarge recovery judgment voltage division (VDD_DIV_UVhys) output by the voltage divider circuit are not fixed. , which can be determined according to the protection threshold set corresponding to the battery. For example, in this embodiment, assuming VREF=1V, correspondingly, VDD_DIV_UV=0.357*VDD, VDD_DIV_Uvhys=0.333*VDD, VDD_DIV_OV=0.233*VDD, VDD_DIV_Ovhys=0.244*VDD. Further, when the system enters the overcharge state and no load access is detected, the Loader_IN signal is low level, the data selector mux2_1 selects channel 2, and the VDD_DIV_UVhys signal is compared with VREF. At this time, there is 0.333*VDD= 1V, the overcharge recovery voltage is 4.1V. After the load connection is detected, the Loader_IN signal is high, the data selector mux2_2 selects channel 1, and the VDD_DIV_OV signal is sent to VREF for comparison. At this time, there is 0.233*VDD=1V, and the overcharge recovery voltage is 4.3V. Equal to overcharge protection voltage value without hysteresis voltage. When the system enters the over-discharge state, no external charging device is detected, the Charger_IN signal is low, the data selector mux2_1 selects channel 2, and the VDD_DIV_UVhys signal is sent to VREF for comparison. At this time, there is 0.333*VDD= 1V, the overcharge recovery voltage is 3V. After detecting that the external charging device is connected, the Charger_IN signal is high level, the data selector mux2_2 selects channel 1, and the VDD_DIV_UV signal is sent in and compared with VREF. At this time, there is 0.357*VDD=1V, and the over-discharge recovery voltage is 2.8 V, equal to the overdischarge protection voltage value without hysteresis voltage.

In one embodiment, as shown in FIG. 5 , the charge-discharge overcurrent detection circuit includes a first switch S1, a second switch S2, a first resistor R1, a second resistor R2, a current comparator and a second logical OR gate OR2, The control parts of the first switch S1 and the second switch S2 are connected to the signal generating circuit, the first switch S1 is connected in series with the connection line between the reference circuit and the first end of the current comparator, and the second switch S2 is connected in series with the reference circuit and the current comparator The connection line of the second end of the current comparator, the first end of the current comparator is also grounded through the first resistor R1, the second end of the current comparator is also connected to the negative terminal of the charging and discharging loop through the second resistor R2, and the second logic OR gate OR2 The signal generating circuit is connected to the third terminal of the current comparator, and the fourth terminal of the current comparator is connected to the logic driving circuit.

Wherein, the first terminal of the current comparator may be the non-inverting terminal or the inverting terminal, and the corresponding second terminal of the current comparator may be the inverting terminal or the non-inverting terminal, which can be set according to the actual situation and is not limited. In this embodiment, the first terminal of the current comparator is the inverting terminal, and the second terminal of the current comparator is the non-inverting terminal as an example for explanation. The control terminal of the first switch S1 is connected to the discharge overcurrent detection signal (DOC_DET), and the control terminal of the second switch S2 is connected to the charging overcurrent detection signal (COC_DET).

Specifically, the second logical OR gate OR2 is used to receive the charge overcurrent detection signal (COC_DET) and the discharge overcurrent detection signal (DOC_DET), and output the signal according to the charge overcurrent detection signal (COC_DET) and the discharge overcurrent detection signal (DOC_DET) The current comparator enable signal to control the working state of the current comparator. When the charging overcurrent detection signal (COC_DET) or the discharging overcurrent detection signal (DOC_DET) is in a high state, the second logic OR gate OR2 outputs a current comparator enable signal to control the current comparator to enable operation.

Further, when receiving the discharge overcurrent detection signal (DOC_DET), the first switch S1 is controlled to be turned on, and the reference current IREF flows through the first resistor R1. The current comparator compares the voltage value of the negative terminal of the charging and discharging loop with the voltage value of the reference current IREF flowing through the first resistor R1, and outputs an overcurrent indication signal. When the voltage value of the negative terminal of the charging and discharging loop is smaller than the voltage value of the reference current IREF flowing through the first resistor R1, the output overcurrent indication signal is low level; when the voltage value of the negative terminal of the charging and discharging loop is greater than or equal to the reference current When IREF flows through the voltage value of the first resistor R1 and the duration is longer than the discharge overcurrent protection delay time, the output overcurrent indication signal is a high level.

When receiving the charging overcurrent detection signal (COC_DET), the second switch S2 is controlled to be turned on, and the reference current IREF flows through the second resistor R2. The current comparator compares the voltage value of the negative terminal of the charging and discharging loop with the voltage value of the reference current IREF flowing through the second resistor R2, and outputs an overcurrent indication signal. When the voltage value of the negative terminal of the charging and discharging loop is greater than the voltage value of the reference current IREF flowing through the second resistor R2, the output overcurrent indication signal is high level; when the voltage value of the negative terminal of the charging and discharging loop is less than or equal to the reference current When IREF flows through the voltage value of the second resistor R2 and the duration is longer than the charging overcurrent protection delay time, the output overcurrent indication signal is a high level.

In one embodiment, the current comparator may be implemented by a common-gate comparator as shown in FIG. 7 , or may be implemented by a common-source comparator as shown in FIG. 8 , and the control principle is the same as the above, and will not be repeated.

In one embodiment, the logic driving circuit includes a voltage comparator output circuit, a current comparator output circuit and a driving output circuit, the voltage comparator output circuit is connected to the signal generating circuit, the voltage comparator and the driving output circuit, and the current comparator output circuit is connected The signal generating circuit, the current comparator and the driving output circuit are connected with the control switch.

Specifically, as shown in FIG. 4 or FIG. 5 , the voltage comparator output circuit is configured to perform logical operations on the detection signal and the overvoltage indication signal to output the driving signal. The voltage comparator output circuit judges and outputs the overcharge driving signal (OV) according to the overcharge detection signal (OV_DET) and the overvoltage indication signal through the first logical AND gate AND1. The voltage comparator output circuit also judges and outputs an over-discharge driving signal (UV) according to the over-discharge detection signal (UV_DET) and the over-voltage indication signal through the first logic NOT gate NOT1 and the second logic AND gate AND2.

Wherein, the first input terminal of the first logical AND gate AND1 is connected to the signal generating circuit to receive the overcharge detection signal (OV_DET), the second input terminal of the first logical AND gate AND1 is connected to the output terminal of the voltage comparator to receive the overvoltage indication signal, The output end of the first logical AND gate AND1 is connected to the driving output circuit. When the overcharge detection signal (OV_DET) is at a high level and the overvoltage indication signal output by the voltage comparator is at a high level, the first logic AND gate AND1 outputs the overcharge drive signal (OV) at a high level to the drive output circuit .

The input end of the first logic NOT gate NOT1 is connected to the output end of the voltage comparator to receive the overvoltage indication signal, the output end of the first logic NOT gate NOT1 is connected to the first input end of the second logic AND gate AND2, and the second logic AND gate AND2 The second input terminal of the second input terminal is connected to the signal generating circuit to receive the over-discharge detection signal (UV_DET), and the output terminal of the second logical AND gate AND2 is connected to the driving output circuit. When the over-discharge detection signal (UV_DET) is at a high level and the over-voltage indication signal output by the voltage comparator is at a low level, the first logic AND gate AND1 outputs the over-discharge drive signal (UV) at a high level to the drive output circuit .

Further, as shown in FIG. 6 , the current comparator output circuit is configured to perform logical operations on the detection signal and the overcurrent indication signal to output the drive signal. The current comparator output circuit judges and outputs the discharge overcurrent drive signal (DOC) according to the discharge overcurrent detection signal (DOC_DET) and the overcurrent indication signal through the third logical AND gate AND3. The current comparator output circuit also judges and outputs a charging overcurrent driving signal (COC) according to the charging overcurrent detection signal (COC_DET) and the overcurrent indication signal through the second logical NOT gate NOT2 and the fourth logical AND gate AND4.

The first input terminal of the third logical AND gate AND3 is connected to the signal generating circuit to receive the discharge overcurrent detection signal (DOC_DET), and the second input terminal of the third logical AND gate AND3 is connected to the output terminal of the current comparator to receive the overcurrent indication signal. , the output end of the third logical AND gate AND3 is connected to the driving output circuit. When the discharge overcurrent detection signal (DOC_DET) is at a high level and the overcurrent indication signal output by the current comparator is at a high level, the third logic AND gate AND3 outputs a discharge overcurrent drive signal (DOC) at a high level to drive output circuit.

The input end of the second logic NOT gate NOT2 is connected to the output end of the current comparator to receive the overcurrent indication signal, the output end of the second logic NOT gate NOT2 is connected to the first input end of the fourth logic AND gate AND4, and the fourth logic AND gate AND4 The second input terminal of the second input terminal is connected to the signal generating circuit to receive the charging overcurrent detection signal (COC_DET), and the output terminal of the fourth logical AND gate AND4 is connected to the driving output circuit. When the charging overcurrent detection signal (COC_DET) is at a high level and the overcurrent indication signal output by the current comparator is at a low level, the fourth logic AND gate AND4 outputs a charging overcurrent drive signal (COC) at a high level to drive output circuit.

Further, the driving output circuit is used for receiving the driving signals respectively output by the voltage comparator output circuit and the current comparator output circuit, and judging and outputting the total driving signal to the control switch. Specifically, when the drive output circuit receives the overcharge drive signal (OV), overdischarge drive signal (UV), charge overcurrent drive signal (COC) and discharge overcurrent drive signal (DOC), the drive signal is at a high level , the drive control switch is switched to the off state, and the charging and discharging circuit between the battery and the external equipment is cut off. When the received overcharge drive signal (OV), overdischarge drive signal (UV), charge overcurrent drive signal (COC) and discharge overcurrent drive signal (DOC) are all low levels, the drive control switch switches to the on state , turn on the charging and discharging circuit of the battery and external equipment.

It can be understood that when it is judged that the current detection state is the overcharge detection state or the charging overcurrent detection state according to the detection signal and the indication signal, and there is an error or the error is not resolved, the drive output circuit can output the drive signal to cut off the battery and the external The device's charging loop, while retaining the discharge loop. When it is judged that the current detection state is the overdischarge detection state or the discharge overcurrent detection state according to the detection signal and the indication signal, and there is an error or the error is not resolved, the drive output circuit can output the drive signal to cut off the discharge of the battery and external equipment circuit, while retaining the charging circuit. The specific implementation means is not unique, and can be determined according to the type of the control switch.

In one embodiment, when the control switch is a single power transistor structure as shown in FIG. 1 , the logic driving circuit further includes a substrate selection circuit, and the substrate selection circuit is connected to the driving output circuit and the control switch.

Specifically, when the received overcharge drive signal (OV) or charge overcurrent drive signal (COC) is at a high level, the drive output circuit first outputs the drive signal to the gate of the single power transistor through the output terminal 1 to drive the single power transistor Switch to disconnected state. Further, the overcharge drive signal (OV) or the charge overcurrent drive signal (COC) is also used to output to the substrate selection circuit, so that the substrate selection circuit outputs the substrate selection signal through the output terminal 2, and the single power transistor The substrate is connected to the terminal VM, leaving the discharge loop and cutting off the charging loop, as shown in FIG. 9 .

When the received over-discharge drive signal (UV) or discharge over-current drive signal (DOC) is high, the drive output circuit first outputs the drive signal to the gate of the single power tube through output terminal 1, and drives the single power tube to switch off. open state. Further, the overdischarge drive signal (UV) or the discharge overcurrent drive signal (DOC) is also used to output to the substrate selection circuit, so that the substrate selection circuit outputs the substrate selection signal through the output terminal 2, and the The substrate is connected to the terminal GND, the discharge loop is reserved and the charging loop is cut off, as shown in Figure 10.

In one embodiment, as shown in FIG. 2 , the control switch is a dual power transistor structure, including a power transistor Q1 and a power transistor Q2. Specifically, when the received overcharge drive signal (OV) or charge overcurrent drive signal (COC) is at a high level, the drive output circuit first outputs the drive signal to the gate of the power transistor Q2 through the output terminal 1 (DO terminal), The driving power tube Q2 is switched to the off state, and the charging circuit is cut off. The discharge loop can be retained through the parasitic diode of the power transistor Q2 and the power transistor Q1. When the received over-discharge drive signal (UV) or discharge over-current drive signal (DOC) is high, the drive output circuit first outputs the drive signal to the gate of the power transistor Q1 through the output terminal 2 (CO terminal) to drive the power transistor. Q1 is switched to the off state to cut off the discharge circuit. The impulse circuit can be retained through the parasitic diode of the power transistor Q1 and the power transistor Q2.

In one embodiment, as shown in FIG. 2 , a battery device is provided, which includes a battery and the above-mentioned battery protection chip, and the battery is connected to the battery protection chip.

Specifically, the battery of the battery device includes a total positive terminal B+ and a total negative terminal B-, and the total positive terminal B+ and the total negative terminal B- of the battery are respectively connected to external equipment through an external positive terminal P+ and an external negative terminal P-. The external device connected by the battery through two external terminals is not unique. It can be connected to the load to form a discharge circuit, and the battery can be used to supply power to the load; it can also be connected to an external charging device to form a charging circuit, and the battery can be charged by an external charging device.

The control switch of the battery protection chip is arranged on the connection line between the total positive terminal B+ of the battery and the external positive terminal P+ or the connection line between the total negative terminal B- and the external negative terminal P-, which is used to control the discharge circuit or charging of the battery and external equipment. Whether the loop is open. It can be understood that the battery protection chip uses a signal generating circuit, a detection circuit and a logic driving circuit to output a driving signal to control the switch to switch its on-off state, so as to monitor and manage the working state of the battery pack.

For specific limitations in the embodiments of the battery device, reference may be made to the limitations on the battery protection chip above, which will not be repeated here.

The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity, all possible combinations of the technical features in the above-described embodiments are not described. However, as long as there is no contradiction between the combinations of these technical features, All should be regarded as the scope described in this specification.

The above-mentioned embodiments only represent several embodiments of the present application, and the descriptions thereof are specific and detailed, but should not be construed as a limitation on the scope of the invention patent. It should be pointed out that for those skilled in the art, without departing from the concept of the present application, several modifications and improvements can be made, which all belong to the protection scope of the present application. Therefore, the scope of protection of the patent of the present application shall be subject to the appended claims.

Claims (10)

1. A battery protection chip is characterized by comprising a signal generation circuit, a detection circuit, a logic drive circuit and a control switch, wherein the signal generation circuit is connected with the detection circuit and the logic drive circuit, the detection circuit is connected with the logic drive circuit and a battery, and the control switch is arranged in a charge-discharge loop of the battery and external equipment and is connected with the logic drive circuit;

the signal generating circuit is used for generating a detection signal and sending the detection signal to the detection circuit and the logic driving circuit; the number of the detection signals is more than two, and the detection signals are used for controlling the detection circuit to enter a detection state corresponding to the detection signals in a time-sharing manner;

when receiving the detection signal, the detection circuit enters a detection state corresponding to the detection signal to detect the working parameter of the battery, and outputs an indication signal to the logic driving circuit according to the working parameter of the battery;

the logic driving circuit generates a driving signal according to the detection signal and the indication signal; the driving signal is used for driving the control switch to switch the on-off state.

2. The battery protection chip of claim 1, further comprising a reference circuit, the reference circuit connecting the signal generating circuit and the detection circuit;

the signal generating circuit is also used for generating a reference enabling signal according to the detection signal and sending the reference enabling signal to the reference circuit;

and the reference circuit generates a reference parameter to the detection circuit when receiving the reference enabling signal.

3. The battery protection chip of claim 2, wherein the detection signals comprise an overcharge detection signal, an overdischarge detection signal, a charge overcurrent detection signal, and a discharge overcurrent detection signal; the detection circuit comprises a charging and discharging overcurrent detection circuit and an overcharge and overdischarge detection circuit, the charging and discharging overcurrent detection circuit is connected with the signal generation circuit, the reference circuit and the logic drive circuit, and the overcharge and overdischarge detection circuit is connected with the signal generation circuit, the reference circuit, the battery and the logic drive circuit;

the charging and discharging overcurrent detection circuit is used for detecting the current parameter of the battery when receiving the charging overcurrent detection signal or the discharging overcurrent detection signal and outputting an overcurrent indication signal to the logic drive circuit according to the current parameter of the battery;

the overcharge and overdischarge detection circuit is used for detecting the voltage parameter of the battery when receiving the overcharge detection signal or the overdischarge detection signal and outputting an overvoltage indication signal to the logic drive circuit according to the voltage parameter of the battery.

4. The battery protection chip of claim 3, wherein the overcharge and overdischarge detection circuit comprises a voltage divider circuit and a voltage detection circuit, the voltage divider circuit connects the battery, the signal generation circuit and the voltage detection circuit, and the voltage detection circuit connects the signal generation circuit, the reference circuit and the logic driving circuit.

5. The battery protection chip of claim 4, wherein the voltage detection circuit comprises a first data selector, a voltage comparator and a first logical OR gate, the first data selector connects the voltage divider circuit, the signal generation circuit and the voltage comparator, the voltage comparator connects the reference circuit, the first logical OR gate and the logic driving circuit, and the first logical OR gate connects the signal generation circuit.

6. The battery protection chip of claim 5, wherein the charging/discharging over-current detection circuit comprises a first switch, a second switch, a first resistor, a second resistor, a current comparator and a second logic OR gate, the first switch and the control part of the second switch are connected with the signal generating circuit, the first switch is connected in series with a connecting line of the reference circuit and the first end of the current comparator, the second switch is connected in series with a connection line of the reference circuit and the second end of the current comparator, the first end of the current comparator is grounded through a first resistor, the second end of the current comparator is connected with the negative terminal of the charge-discharge loop through a second resistor, the second logic OR gate is connected with the signal generating circuit and the third end of the current comparator, and the fourth end of the current comparator is connected with the logic driving circuit.

7. The battery protection chip according to claim 6, wherein the logic driving circuit comprises a voltage comparator output circuit, a current comparator output circuit and a driving output circuit, the voltage comparator output circuit is connected with the signal generating circuit, the voltage comparator and the driving output circuit, the current comparator output circuit is connected with the signal generating circuit, the current comparator and the driving output circuit, and the driving output circuit is connected with the control switch.

8. The battery protection chip of claim 7, wherein when the control switch is a single power tube structure, the logic driving circuit further comprises a substrate selection circuit, and the substrate selection circuit connects the driving output circuit and the control switch.

9. The battery protection chip according to any one of claims 1 to 8, wherein the signal generation circuit comprises a clock circuit and a state machine, the clock circuit is connected with the state machine, and the state machine is connected with the detection circuit and the logic driving circuit.

10. A battery device, comprising a battery and the battery protection chip of any one of claims 1 to 9, wherein the battery is connected to the battery protection chip.

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