Protection circuit, battery protection chip and electronic device

Abstract

The present invention discloses a protection circuit, a battery protection chip and an electronic device. The protection circuit is used for the battery protection chip, connects to the battery power supply terminal and receives the battery voltage, and includes a pulse generation circuit, a voltage judgment circuit and a logic processing circuit. The pulse generation circuit receives a power-on signal and outputs a power-on pulse signal. When the level of the power-on signal changes, the level of the power-on pulse signal changes and maintains a preset duration. The voltage judgment circuit is connected to the pulse generation circuit and outputs a low-voltage protection signal. When the level of the power-on pulse signal changes and maintains a preset duration and meets a second preset condition, the level of the low-voltage protection signal changes. The logic processing circuit is connected to the voltage judgment circuit and outputs a power-on detection signal. The power-on detection signal is used to activate the battery protection chip. The above protection circuit generates a pulse, and correspondingly outputs a low-voltage protection signal when the pulse lasts, so that the power-on detection signal changes and activates the battery protection chip, without manual operation, which is beneficial to improving the production line efficiency.

Description

Technical Field

[0001] The present invention relates to the field of electronic integration technology, and particularly relates to a protection circuit, a battery protection chip, and an electronic device. Background Art

[0002] In the related art, a battery protection chip is used to provide protection for a battery, and can prevent the battery from being damaged due to over-discharge. In actual production, after the assembly between the battery protection chip and the battery is completed, the battery is subjected to over-discharge dormancy processing. Since the battery protection chip is in a dormant state at this time, the battery protection chip needs to be powered on and activated, and this operation often needs to be realized through manual operation, thus easily affecting the production line efficiency. Summary of the Invention

[0003] The present invention provides a protection circuit, a battery protection chip, and an electronic device.

[0004] A protection circuit provided by an embodiment of the present invention is used for a battery protection chip. The protection circuit is connected to the power supply terminal of the battery and receives the battery voltage. The protection circuit includes:

[0005] A pulse generation circuit, configured to receive a power-on signal and output a power-on pulse signal. When the power-on signal changes in level, the power-on pulse signal changes in level correspondingly and maintains a preset duration. When the battery voltage meets a first preset condition, the power-on signal changes in level, and the level change includes changing from a low level to a high level and changing from a high level to a low level;

[0006] A voltage judgment circuit, connected to the pulse generation circuit, configured to output a low-voltage protection signal according to the power-on pulse signal, the battery voltage, and a reference voltage. When the power-on pulse signal changes in level and maintains the preset duration, and the difference between the battery voltage and the reference voltage meets a second preset condition, the low-voltage protection signal changes in level; and

[0007] A logic processing circuit, connected to the voltage judgment circuit, configured to output a power-on detection signal according to the power-on signal and the low-voltage protection signal, and the power-on detection signal is used to activate the battery protection chip.

[0008] When the above protection circuit performs over-discharge dormancy on the battery, the power-on signal changes in level according to the battery voltage to generate a pulse. When the pulse lasts for the preset duration, the low-voltage protection signal can be correspondingly output according to the difference between the battery voltage and the reference voltage, so that the power-on detection signal changes in level to activate the battery protection chip, without manual operation, which is beneficial to improving the production line efficiency.

[0009] In some embodiments, the pulse generation circuit includes:

[0010] A first valve unit for outputting a first level signal to a first point, wherein the level change of the first level signal corresponds to the level change of the power-on signal;

[0011] A flow rate buffering unit connected to the first point for adjusting the change speed of the voltage value of the first level signal;

[0012] A delay unit for outputting a second level signal, and when the voltage value of the first level signal changes to a flip threshold, the second level signal changes in level; and

[0013] A first logic unit for outputting the power-on pulse signal according to the power-on signal and the second level signal.

[0014] In some embodiments, the flow rate buffering unit includes:

[0015] A constant current source for providing a constant current from the first point to the ground point to discharge the first point;

[0016] A flow rate buffering capacitor connected in parallel with the constant current source for cooperating with the constant current source to adjust the discharge speed at the first point.

[0017] In some embodiments, when the level changes of the power-on signal and the second level signal are opposite, the first logic unit is configured to output the power-on pulse signal with a low level when the power-on signal and the second level signal have the same level, and output the power-on pulse signal with a high level when the power-on signal and the second level signal have different levels; or

[0018] When the level changes of the power-on signal and the second level signal are the same, the first logic unit is configured to output the power-on pulse signal with a low level when the power-on signal and the second level signal have different levels, and output the power-on pulse signal with a high level when the power-on signal and the second level signal have the same level.

[0019] In some embodiments, the voltage judgment circuit includes:

[0020] A second valve unit connected to the power supply terminal and a second point for conducting the power supply terminal and the second point when the difference between the battery voltage and the reference voltage satisfies the second preset condition;

[0021] A third valve unit connected to the second point and a third point for conducting the second point and the third point when the power-on pulse signal changes in level and maintains the preset duration;

[0022] When the power supply terminal is electrically connected to the second point and the second point is electrically connected to the third point, the voltage judgment circuit outputs the low-voltage protection signal at the third point.

[0023] In some embodiments, the second preset condition includes:

[0024] The difference between the battery voltage and the reference voltage is greater than a preset voltage threshold.

[0025] In some embodiments, the logic processing circuit includes:

[0026] A second logic unit configured to output a third-level signal according to the power-on signal and the low-voltage protection signal; and

[0027] A third logic unit connected to the second logic unit and the over-discharge detection circuit, configured to output the power-on detection signal according to the third-level signal and the over-discharge detection signal, where the over-discharge detection circuit is configured to output the over-discharge detection signal according to the discharge state of the battery, and the level of the over-discharge detection signal corresponds to the discharge state of the battery.

[0028] In some embodiments, the protection circuit includes:

[0029] A signal driving unit including an even number of sequentially connected logic NOT gates, and the signal driving unit is disposed in at least one of the pulse generating circuit, the voltage judgment circuit, and the logic processing circuit.

[0030] A battery protection chip provided by an embodiment of the present invention for a battery, characterized by including:

[0031] The protection circuit according to any of the above embodiments.

[0032] When the above protection circuit performs over-discharge dormancy on the battery, the power-on signal changes in level according to the battery voltage to generate a pulse. When the pulse lasts for a preset duration, the low-voltage protection signal can be output corresponding to the difference between the battery voltage and the reference voltage, so that the power-on detection signal changes in level, activating the battery protection chip without manual operation, which is beneficial to improving the production line efficiency.

[0033] An electronic device provided by an embodiment of the present invention, characterized by including:

[0034] A battery; and

[0035] The battery protection chip according to any of the above embodiments. Description of the Drawings

[0036] The above and / or additional aspects and advantages of the present invention will become apparent and be readily understood from the following description of embodiments in conjunction with the accompanying drawings, where:

[0037] Figure 1 Schematic diagram of the circuit structure of the protection circuit according to an embodiment of the present invention;

[0038] Figure 2 Schematic diagram of the circuit structure of the pulse generation circuit according to an embodiment of the present invention;

[0039] Figure 3 Timing diagram of the pulse generation circuit according to an embodiment of the present invention;

[0040] Figure 4 Timing diagram of another pulse generation circuit according to an embodiment of the present invention;

[0041] Figure 5 Schematic diagram of the circuit structure of the voltage judgment circuit according to an embodiment of the present invention;

[0042] Figure 6 Schematic diagram of the circuit structure of the logic processing circuit according to an embodiment of the present invention;

[0043] Figure 7 Schematic diagram of the circuit structure of the electronic device according to an embodiment of the present invention;

[0044] Figure 8 Schematic diagram of the circuit structure of another electronic device according to an embodiment of the present invention.

[0045] Description of main component symbols:

[0046] 100 - Electronic device; 200 - Battery; 210 - Power supply terminal; 300 - Battery protection chip; 400 - Protection circuit; 410 - Pulse generation circuit; 411 - First valve unit; 412 - Flow - buffering unit; 413 - Constant current source; 414 - Flow - buffering capacitor; 415 - Delay circuit; 416 - First logic unit; 417 - First point; 420 - Voltage judgment circuit; 421 - Second valve unit; 422 - Third valve unit; 423 - Second point; 424 - Third point; 430 - Logic processing circuit; 431 - Second logic unit; 432 - Third logic unit; 440 - Signal driving unit; 441 - Logic NOT gate; 500 - Over - discharge detection circuit; 510 - Over - discharge detection signal; 600 - First logic control circuit; 601 - Second logic control circuit; 610 - Delay circuit; 620 - Driving circuit; 630 - First power switch tube; 631 - Second power switch tube; 632 - Third power switch tube; 640 - First over - charge detection circuit; 641 - Second over - charge detection circuit; 650 - First over - current protection circuit; 651 - Second over - current protection circuit; 660 - Substrate selection circuit; 700 - Power - on signal; 710 - Power - on pulse signal; 720 - Low - voltage protection signal; 730 - Power - on detection signal; 740 - First level signal; 750 - Second level signal; 760 - Third level signal. Detailed implementation manners

[0047] The following details the implementation manners of the present invention. Examples of the implementation manners are shown in the accompanying drawings, where the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions throughout. The implementation manners described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention and should not be construed as a limitation of the present invention.

[0048] The following disclosure provides many different implementation manners or examples for implementing different structures of the present invention. To simplify the disclosure of the present invention, components and settings of specific examples are described below. Of course, they are only examples and are not intended to limit the present invention. In addition, the present invention may repeat reference numerals and / or reference letters in different examples. This repetition is for the purpose of simplification and clarity and does not itself indicate the relationship between the various implementation manners and / or settings discussed. In addition, the present invention provides examples of various specific processes and materials, but those of ordinary skill in the art can be aware of the application of other processes and / or the use of other materials.

[0049] Please refer to Figure 1 、 Figure 7 and Figure 8 , a protection circuit 400 provided by an implementation manner of the present invention, which is used for a battery protection chip 300. The protection circuit 400 is connected to the power supply terminal 210 of the battery 200 and receives the battery voltage. Please refer toFigure 1 The protection circuit 400 includes a pulse generation circuit 410, a voltage judgment circuit 420, and a logic processing circuit 430. The pulse generation circuit 410 is configured to receive a power-on signal 700 and output a power-on pulse signal 710. When the power-on signal 700 changes in level, the power-on pulse signal 710 changes in level correspondingly and maintains a preset duration. When the battery voltage meets a first preset condition, the power-on signal 700 changes in level. The level change includes changing from a low level to a high level and changing from a high level to a low level. The voltage judgment circuit 420 is connected to the pulse generation circuit 410 and is configured to output a low-voltage protection signal 720 according to the power-on pulse signal 710, the battery voltage, and a reference voltage. When the power-on pulse signal 710 changes in level and maintains a preset duration, and the difference between the battery voltage and the reference voltage meets a second preset condition, the low-voltage protection signal 720 changes in level. The logic processing circuit 430 is connected to the voltage judgment circuit 420 and is configured to output a power-on detection signal 730 according to the power-on signal 700 and the low-voltage protection signal 720. The power-on detection signal 730 is used to activate the battery protection chip 300.

[0050] For the above protection circuit 400, when over-discharging and putting the battery 200 into sleep mode, the power-on signal 700 changes in level according to the battery voltage to generate a pulse. When the pulse lasts for a preset duration, the low-voltage protection signal 720 can be correspondingly output according to the difference between the battery voltage and the reference voltage, so that the power-on detection signal 730 changes in level to activate the battery protection chip 300, without manual operation, which is beneficial to improving the production line efficiency.

[0051] Specifically, please refer to Figure 1 , in one embodiment, the battery voltage does not meet the first preset condition. The battery 200 is in an over-discharged state. The pulse generation circuit 410 does not receive an effective level change; the logic processing circuit 430 outputs a low level; the battery protection chip 300 is not activated. In another embodiment, the battery voltage meets the first preset condition and does not meet the second preset condition. The battery 200 is still in an over-discharged state. The pulse generation circuit 410 outputs a valid power-on pulse signal 710; the voltage judgment circuit 420 outputs a low level; the logic processing circuit 430 outputs a low level; the battery protection chip 300 is not activated. In yet another embodiment, the battery voltage meets the second preset condition. The pulse generation circuit 410 outputs a valid power-on pulse signal 710; the voltage judgment circuit 420 outputs a high level; the logic processing circuit 430 outputs a high level; the battery protection chip 300 is activated.

[0052] In addition, in some embodiments, the first preset condition is that the voltage is greater than or equal to 1 volt. The second preset condition is that the voltage is greater than 1.7 volts. The judgment voltage of the first preset condition is less than the judgment voltage of the second preset condition.

[0053] Please refer to Figure 2 In some embodiments, the pulse generation circuit 410 includes a first valve unit 411, a flow buffer unit 412, a delay unit 415, and a first logic unit 416. The first valve unit 411 is configured to output a first level signal 740 to a first point 417. The level change of the first level signal 740 corresponds to the level change of the power-on signal 700. The flow buffer unit 412 is connected to the first point 417 and is used to adjust the change speed of the voltage value of the first level signal 740. The delay unit 415 is configured to output a second level signal 750. When the voltage value of the first level signal 740 changes to the flip threshold, the second level signal 750 changes in level. The first logic unit 416 is configured to output a power-on pulse signal 710 according to the power-on signal 700 and the second level signal 750.

[0054] In this way, the pulse generation circuit 410 can generate a pulse signal.

[0055] Specifically, please refer to Figure 2 In one embodiment, the gate of the first valve unit 411 inputs the power-on signal 700, the drain is connected to the power supply terminal 210, and the source is connected to the first point 417. When the battery voltage does not meet the first preset condition, the power-on signal 700 is at a low level, the power supply terminal 210 is conducted with the first point 417, and the first level signal 740 is at a high level. The delay unit 415 outputs the second level signal 750 at a high level. The first logic unit 416 outputs the power-on pulse signal 710 at a high level. When the battery voltage meets the first preset condition, the power-on signal 700 is at a high level, and the power supply terminal 210 is cut off from the first point 417. The flow buffer unit 412 maintains the voltage of the first point 417 to decrease slowly. When the voltage of the first point 417 is greater than the flip threshold of the delay unit 415, the first level signal 740 is at a high level. The delay unit 415 outputs the second level signal 750 at a high level. The first logic unit 416 outputs the power-on pulse signal 710 at a low level. When the voltage of the first point 417 is less than the flip threshold of the delay unit 415, the first level signal 740 is at a low level. The delay unit 415 outputs the second level signal 750 at a low level. The first logic unit 416 outputs the power-on pulse signal 710 at a low level. It can be understood that after the first valve unit 411 is closed, the time for the voltage of the first point 417 to drop to the flip threshold of the delay unit 415 is the preset duration of the pulse signal.

[0056] In addition, please refer to Figure 2 In one embodiment, the delay unit 415 is a Schmitt trigger, which is used to shape the signal waveform and enhance the anti-interference ability. When the battery protection chip 300 is powered on or when the first valve unit 411 is turned on or off instantaneously, the delay unit 415 can stably output.

[0057] Please refer toFigure 2 , in some embodiments, the slow current unit 412 includes a constant current source 413 and a slow current capacitor 414. The constant current source 413 is used to provide a constant current from the first point 417 to the ground point to discharge the first point 417. The slow current capacitor 414 is connected in parallel with the constant current source 413 and is used to cooperate with the constant current source 413 to adjust the discharge speed at the first point 417.

[0058] In this way, the effect of slowly reducing the voltage is achieved.

[0059] Specifically, please refer to Figure 2 , in one embodiment, the battery voltage satisfies the first preset condition. The power-on signal 700 is at a high level. The battery 200 is connected to the power supply terminal 210, causing the voltage of the power supply terminal 210 to rise. Before the voltage of the power supply terminal 210 rises to the point where the first valve unit 411 closes, the power supply terminal 210 is conducted to the ground point, and the slow current capacitor 414 starts to charge. After the first valve unit 411 closes, the slow current capacitor 414 forms a path with the constant current source 413. The slow current capacitor 414 slowly discharges through the constant current source 413 to maintain the stability of the pulse signal.

[0060] Please refer to Figure 3 , in some embodiments, when the level changes of the power-on signal 700 and the second level signal 750 are in the reverse direction, the first logic unit 416 is used to output a low-level power-on pulse signal 710 when the power-on signal 700 and the second level signal 750 have the same level, and output a high-level power-on pulse signal 710 when the power-on signal 700 and the second level signal 750 have different levels.

[0061] In this way, the pulse generation circuit 410 can output a low level only when the pulse signal lasts.

[0062] Specifically, please refer to Figure 2 , in one embodiment, the first logic unit 416 is a NAND gate. The input terminals of the first logic unit 416 include the power-on signal 700 and the second level signal 750. Please refer to Figure 3, when the battery voltage does not meet the first preset condition, the power-on signal 700 is at a low level. The voltage value of the first point 417 is high. The second level signal 750 is at a high level. The first logic unit 416 outputs a power-on pulse signal 710 at a high level. When the battery voltage meets the first preset condition and the power-on pulse signal 710 changes in level and maintains a preset duration, the power-on signal 700 is at a high level. The voltage value of the first point 417 gradually decreases from high. At this time, the second level signal 750 is still at a high level. The first logic unit 416 outputs a power-on pulse signal 710 at a low level. When the battery voltage meets the first preset condition and the power-on pulse signal 710 returns to its original level, the power-on signal 700 is at a high level. The voltage value of the first point 417 is less than the flip threshold of the delay unit 415, and the second level signal 750 turns to a low level. The first logic unit 416 outputs a power-on pulse signal 710 at a high level.

[0063] In addition, in another embodiment, the first logic unit 416 is a NAND-XOR gate. The input terminals of the first logic unit 416 include the power-on signal 700 and the second level signal 750. Please refer to Figure 4 , when the battery voltage does not meet the first preset condition, the power-on signal 700 is at a low level. The voltage value of the first point 417 is low. The second level signal 750 is at a low level. The first logic unit 416 outputs a power-on pulse signal 710 at a high level. When the battery voltage meets the first preset condition and the power-on pulse signal 710 changes in level and maintains a preset duration, the power-on signal 700 is at a high level. The voltage value of the first point 417 gradually increases from low. At this time, the second level signal 750 is still at a low level. The first logic unit 416 outputs a power-on pulse signal 710 at a low level. When the battery voltage meets the first preset condition and the power-on pulse signal 710 returns to its original level, the power-on signal 700 is at a high level. The voltage value of the first point 417 is greater than the flip threshold of the delay unit 415, and the second level signal 750 turns to a high level. The first logic unit 416 outputs a power-on pulse signal 710 at a high level.

[0064] Please refer to Figure 5, in some embodiments, the voltage determination circuit 420 includes a second valve unit 421 and a third valve unit 422. The second valve unit 421 is connected to the power supply terminal 210 and the second point 423, and is configured to conduct the power supply terminal 210 and the second point 423 when the difference between the battery voltage and the reference voltage satisfies a second preset condition. The third valve unit 422 is connected to the second point 423 and the third point 424, and is configured to conduct the second point 423 and the third point 424 when the power-on pulse signal 710 changes in level and maintains a preset duration. When the power supply terminal 210 and the second point 423 are conducted, and the second point 423 and the third point 424 are conducted, the voltage determination circuit 420 outputs a low-voltage protection signal 720 at the third point 424.

[0065] In this way, the voltage determination circuit 420 can determine whether the battery voltage satisfies the second preset condition.

[0066] Specifically, please refer to Figure 5 , in one embodiment, the gate of the second valve unit 421 receives the reference voltage, the drain is connected to the power supply terminal 210, and the source is connected to the second point 423. When the battery voltage satisfies the second preset condition, the power supply terminal 210 and the second point 423 are conducted. When the battery voltage does not satisfy the second preset condition, the power supply terminal 210 and the second point 423 are cut off. In another embodiment, the gate of the third valve unit 422 receives the power-on pulse signal 710, the drain is connected to the second point 423, and the source is connected to the third point 424. When the power-on pulse signal 710 is at a low level, the second point 423 and the third point 424 are conducted. When the power-on pulse signal 710 is at a high level, the second point 423 and the third point 424 are cut off. It can be understood that when the second valve unit 421 and the third valve unit 422 are both conducted, a high-level low-voltage protection signal 720 will be output at the third point 424. When one of the second valve unit 421 and the third valve unit 422 is closed, a low-level low-voltage protection signal 720 will be output at the third point 424.

[0067] Please refer to Figure 5 , in some embodiments, the second preset condition includes that the difference between the battery voltage and the reference voltage is greater than a preset voltage threshold.

[0068] In this way, it can be determined whether the battery 200 has the ability to activate the battery protection chip 300.

[0069] Specifically, please refer to Figure 5 , in one embodiment, the sum of the reference voltage and the voltage threshold is 1.7V. When the battery voltage satisfies the second preset condition, the battery voltage is greater than 1.7V, avoiding the influence of too low battery voltage on the normal operation of the battery protection chip 300.

[0070] Please refer to Figure 6 , in some embodiments, the logic processing circuit 430 includes a second logic unit 431 and a third logic unit 432. The second logic unit 431 is configured to output a third-level signal 760 according to the power-on signal 700 and the low-voltage protection signal 720. The third logic unit 432 is connected to the second logic unit 431 and the over-discharge detection circuit 500, and is configured to output a power-on detection signal 730 according to the third-level signal 760 and the over-discharge detection signal 510. The over-discharge detection circuit 500 is configured to output an over-discharge detection signal 510 according to the discharge state of the battery 200. The level of the over-discharge detection signal 510 corresponds to the discharge state of the battery 200.

[0071] In this way, normal over-discharge protection can be ensured.

[0072] Specifically, please refer to Figure 6, in one embodiment, the second logic unit 431 is a NAND gate, and its input terminals include a power-on signal 700 and a low-voltage protection signal 720. The second logic unit 431 outputs a third-level signal 760. In another embodiment, the third logic unit 432 is an exclusive-OR gate, and its input terminals include the logical negation of the third-level signal 760 and an over-discharge detection signal 510. The third logic unit 432 outputs a power-on detection signal 730. In some embodiments, when the battery voltage does not meet the first preset condition, the power-on signal 700 is at a low level, and the low-voltage protection signal 720 is at a low level. The second logic unit 431 outputs a high-level third-level signal 760. At this time, the battery protection chip 300 is not activated, and the over-discharge detection signal 510 is at a low level. The logic processing circuit 430 outputs a low-level power-on detection signal 730. When the battery voltage meets the first preset condition and does not meet the second preset condition, the low-voltage protection signal 720 is at a low level. The second logic unit 431 outputs a high-level third-level signal 760. At this time, the battery protection chip 300 is not activated, and the over-discharge detection signal 510 is at a low level. The logic processing circuit 430 outputs a low-level power-on detection signal 730. When the battery voltage meets the second preset condition and the power-on pulse signal 710 changes in level and maintains a preset duration, the power-on signal 700 is at a high level, and the low-voltage protection signal 720 is at a high level. The second logic unit 431 outputs a low-level third-level signal 760. At this time, the battery protection chip 300 is not activated, and the over-discharge detection signal 510 is at a low level. The logic processing circuit 430 outputs a high-level power-on detection signal 730. The battery protection chip 300 is activated. When the battery voltage meets the second preset condition and the power-on pulse signal 710 returns to its original level, the power-on signal 700 is at a high level, and the low-voltage protection signal 720 is at a high level. The second logic unit 431 outputs a low-level third-level signal 760. At this time, the battery protection chip 300 has been activated, and the over-discharge detection signal 510 is determined by the over-discharge detection circuit 500 according to the discharge state of the battery 200. The logic processing circuit 430 outputs the over-discharge detection signal 510. Thus, it is ensured that the battery protection chip 300 can perform over-discharge protection normally after the power-on ends.

[0073] Please refer to Figure 2 and Figure 5 , in some embodiments, the protection circuit 400 includes a signal driving unit 440. The signal driving unit 440 includes an even number of cascaded logical NOT gates 441 in sequence. The signal driving unit 440 is provided in at least one of the pulse generation circuit 410, the voltage judgment circuit 420, and the logic processing circuit 430.

[0074] In this way, it is beneficial to improve the driving ability of the protection circuit 400.

[0075] Specifically, please refer to Figure 2, in one embodiment, two logic NOT gates 441 are connected in series after the output terminal of the first logic unit 416, which can amplify the power-on pulse signal 710. Please refer to Figure 5 , in one embodiment, two logic NOT gates 441 are connected in series after the third point 424, which can amplify the power-on detection signal 730. It can be understood that, in some embodiments, by notifying the signal driving unit 440 to be set in one or more of the pulse generation circuit 410, the voltage judgment circuit 420, and the logic processing circuit 430, the signal can be amplified and the driving ability can be enhanced.

[0076] Please refer to Figure 7 and Figure 8 , a battery protection chip 300 provided by an embodiment of the present invention is used for the battery 200. The battery protection chip 300 includes the protection circuit 400 of any of the above embodiments.

[0077] When the above protection circuit 400 performs over-discharge dormancy on the battery 200, according to the battery voltage, the power-on signal 700 is made to change in level to generate a pulse. When the pulse lasts for a preset duration, the low-voltage protection signal 720 can be correspondingly output according to the difference between the battery voltage and the reference voltage, and then the power-on detection signal 730 will change in level to activate the battery protection chip 300, without manual operation, which is beneficial to improving the production line efficiency.

[0078] In this way, the battery protection chip 300 can be self-detected and activated when powered on.

[0079] Specifically, please refer to Figure 7 , in one embodiment, when the battery voltage is greater than the second preset condition, after power-on, the protection circuit 400 generates a pulse signal and outputs a high-level power-on detection signal 730. The power-on detection signal 730 is input to the first logic control circuit 600 after being delayed by the delay circuit 610. The first logic control circuit 600 resets the over-discharge detection circuit 500, the first overcharge detection circuit 640, and the first overcurrent protection circuit 650 and conducts the first power switch tube 630. Thus, the battery protection chip 300 is activated. After the pulse signal disappears, the over-discharge detection circuit 500 outputs an over-discharge detection signal 510, which is directly output by the protection circuit 400. The first overcharge detection circuit 640 is used to detect the battery voltage and output a first overcharge detection signal. The first overcurrent protection circuit 650 is used to detect the charging current and discharging current of the battery 200 and output a first overcurrent detection signal. The first logic control circuit 600 receives the delayed over-discharge detection signal 510, the first overcharge detection signal, and the first overcurrent detection signal, and conducts or closes the charge and discharge ports by controlling the first power-on tube 630 to ensure the normal operation of the battery 200.

[0080] In addition, please refer to Figure 8, in another embodiment, when the battery voltage is greater than the second preset condition, after power-on, the protection circuit 400 generates a pulse signal and outputs a power-on detection signal 730 with a high level. The power-on detection signal 730 is input to the second logic control circuit 601. The second logic control circuit 601 resets the over-discharge detection circuit 500, the second overcharge detection circuit 641, and the second over-current protection circuit 651 and conducts the second power switch tube 631 through the drive circuit 620. Thus, the battery protection chip 300 is activated. After the pulse signal disappears, the over-discharge detection circuit 500 outputs an over-discharge detection signal 510, which is directly output by the protection circuit 400. The second overcharge detection circuit 641 is used to detect the battery voltage and output a second overcharge detection signal. The second over-current protection circuit 651 is used to detect the charging current and discharging current of the battery 200 and output a second over-current detection signal. The second logic control circuit 601 receives the delayed over-discharge detection signal 510, the second overcharge detection signal, and the second over-current detection signal and outputs a control signal. The drive circuit 620 receives the control signal to control the second power-on tube 631. The substrate selection circuit 660 receives the control signal to control the third power-on tube 632. Thus, the battery protection chip 300 can conduct or cut off the charge and discharge ports to ensure the normal operation of the battery 200.

[0081] Please refer to Figure 7 and Figure 8 , an electronic device 100 provided by an embodiment of the present invention includes a battery 200 and the battery protection chip 300 of any of the above embodiments.

[0082] In this way, it is beneficial to improve the production line efficiency.

[0083] Specifically, please refer to Figure 7 and Figure 8 , in one embodiment, the battery protection chip 300 self-detects the battery voltage and is activated when the battery voltage meets the requirements without manual operation. Thus, the production line can be optimized.

[0084] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more features. In the description of the present invention, "a plurality" means two or more unless otherwise specifically defined.

[0085] In the description of this specification, the descriptions with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiments or examples are included in at least one embodiment or example of the present invention. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0086] In the description of the present invention, it should be noted that, unless otherwise clearly specified and defined, the terms "mounted", "connected", and "coupled" shall be construed in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection. It may be a mechanical connection or an electrical connection. It may be directly connected or indirectly connected through an intermediate medium, and it may be the internal communication of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0087] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A protection circuit for a battery protection chip, characterized in that, The protection circuit is connected to the power supply terminal of the battery and receives the battery voltage. The protection circuit includes: A pulse generation circuit, configured to receive a power-on signal and output a power-on pulse signal. When the power-on signal changes in level, the power-on pulse signal changes in level accordingly and maintains a preset duration. When the battery voltage meets a first preset condition, the power-on signal changes in level, and the level change includes changing from a low level to a high level and from a high level to a low level; A voltage judgment circuit, connected to the pulse generation circuit, configured to output a low-voltage protection signal according to the power-on pulse signal, the battery voltage, and a reference voltage. When the power-on pulse signal changes in level and maintains the preset duration, and the difference between the battery voltage and the reference voltage meets a second preset condition, the low-voltage protection signal changes in level; and A logic processing circuit, connected to the voltage judgment circuit, configured to output a power-on detection signal according to the power-on signal and the low-voltage protection signal, and the power-on detection signal is used to activate the battery protection chip; Wherein, the voltage judgment circuit includes: A second valve unit, connected to the power supply terminal and a second point, configured to conduct the power supply terminal and the second point when the difference between the battery voltage and the reference voltage meets the second preset condition; A third valve unit, connected to the second point and a third point, configured to conduct the second point and the third point when the power-on pulse signal changes in level and maintains the preset duration; When the power supply terminal and the second point are conducted, and the second point and the third point are conducted, the voltage judgment circuit outputs the low-voltage protection signal at the third point.

2. The protection circuit according to claim 1, wherein The pulse generation circuit includes: A first valve unit, configured to output a first level signal to a first point, and the level change of the first level signal corresponds to the level change of the power-on signal; A current-limiting unit, connected to the first point, configured to adjust the change speed of the voltage value of the first level signal; A delay unit, configured to output a second level signal. When the voltage value of the first level signal changes to a flip threshold, the second level signal changes in level; and A first logic unit, configured to output the power-on pulse signal according to the power-on signal and the second level signal.

3. The protection circuit according to claim 2, characterized in that, The current-limiting unit includes: A constant current source, configured to provide a constant current from the first point to the ground to discharge the first point; A current-limiting capacitor, connected in parallel with the constant current source, configured to cooperate with the constant current source to adjust the discharge speed of the first point.

4. The protection circuit according to claim 2, wherein When the level changes of the power-on signal and the second level signal are opposite, the first logic unit is configured to output the power-on pulse signal with a low level when the power-on signal and the second level signal have the same level, and output the power-on pulse signal with a high level when the power-on signal and the second level signal have different levels; Or When the level changes of the power-on signal and the second level signal are in the same direction, the first logic unit is configured to output the power-on pulse signal with a low level when the power-on signal and the second level signal have different levels, and output the power-on pulse signal with a high level when the power-on signal and the second level signal have the same level.

5. The protection circuit according to claim 1, characterized in that, The second preset condition includes: The difference between the battery voltage and the reference voltage is greater than a preset voltage threshold.

6. The protection circuit according to claim 1, wherein The logic processing circuit includes: A second logic unit configured to output a third level signal according to the power-on signal and the low-voltage protection signal; and A third logic unit connected to the second logic unit and the over-discharge detection circuit, configured to output the power-on detection signal according to the third level signal and the over-discharge detection signal, where the over-discharge detection circuit is configured to output the over-discharge detection signal according to the discharge state of the battery, and the level of the over-discharge detection signal corresponds to the discharge state of the battery.

7. The protection circuit according to any one of claims 1-6, characterized in that, The protection circuit includes: A signal driving unit including an even number of cascaded NOT gates in series, and the signal driving unit is disposed in at least one of the pulse generation circuit, the voltage determination circuit, and the logic processing circuit.

8. A battery protection chip for a battery, characterized in that, Comprising: The protection circuit according to any one of claims 1-7.

9. An electronic device, characterized in that, Comprising: A battery; And The battery protection chip according to claim 8.

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