Short-circuit protection circuit based on adjustable comparator parameters and battery

Abstract

The utility model provides a short-circuit protection circuit based on adjustable comparator parameters and a battery, the short-circuit protection circuit based on adjustable comparator parameters comprises a power supply circuit, a short-circuit signal detection circuit and a protection trigger circuit, the short-circuit signal detection circuit comprises a voltage comparator and a first resistor, the first resistor is connected with a sampling resistor short-circuit detection signal input end, and an output end of the voltage comparator is connected with a short-circuit trigger signal end and used for detecting short-circuit signals. The protection trigger circuit comprises a first capacitor, a fourth resistor, a fifth resistor, a first electronic switching tube and a second electronic switching tube and is used for triggering protection action; the sensitivity of the circuit to the short-circuit current can be flexibly adjusted by adjusting the resistance value of the second resistor; meanwhile, by adjusting the capacitance value of the first capacitor, the response time of the circuit after the short circuit is detected can be adjusted, so that the short-circuit protection circuit based on the adjustable comparator parameters can adapt to the requirements of different application scenes, and the circuit has a self-locking function to prevent misoperation before the short circuit is eliminated.

Description

Technical Field

[0001] The present disclosure relates to the technical field of battery short-circuit protection, and in particular to a short-circuit protection circuit and a battery based on adjustable comparator parameters. Background Art

[0002] With the rapid development of new energy technologies, lithium-ion batteries, as a key component of clean energy, have been widely used in electric vehicles, energy storage systems, portable electronic devices, and other fields. However, lithium-ion batteries face numerous safety hazards during use, particularly short circuits. When a short circuit occurs in a battery pack, a large instantaneous current is generated, causing a sharp increase in the internal temperature of the battery, which may even cause a fire or explosion, posing a serious threat to the safety of personnel and equipment.

[0003] In the existing technology, the battery management system serves as the core control unit of the battery pack, and a short-circuit protection circuit is installed inside it. However, these circuits rely on the protection function of the chip itself. When a short circuit occurs, the short-circuit protection of the chip itself has problems such as a fixed detection range, inflexible adjustment, and the chip may not be able to respond in time due to large delay deviations. Especially in high-energy density or high-voltage battery packs, the chip may not be able to respond in time due to large delay deviations, resulting in protection failure. Utility Model Content

[0004] The purpose of the present disclosure is to overcome the deficiencies in the prior art and to provide a short-circuit protection circuit and a battery based on an adjustable comparator parameter, rapid response, and a self-locking function.

[0005] The purpose of this disclosure is achieved through the following technical solutions:

[0006] A short-circuit protection circuit based on adjustable comparator parameters includes a power supply circuit, a short-circuit signal detection circuit, a protection trigger circuit and an electric energy output circuit. The power supply circuit is used to provide electric energy to the short-circuit signal detection circuit, and the electric energy output circuit is used to control the output of electric energy from a battery.

[0007] The short-circuit signal detection circuit includes a voltage comparator, a first resistor, a second resistor and a third resistor. The first end of the first resistor is used to be connected to the sampling resistor short-circuit detection signal input end, the second end of the first resistor is connected to the positive input end of the voltage comparator, the output end of the voltage comparator is used to be connected to the short-circuit trigger signal end, the first end of the third resistor is connected to the output end of the power supply circuit, the second end of the third resistor is connected to the first end of the second resistor, the first end of the second resistor is connected to the reverse input end of the voltage comparator, and the second end of the second resistor is grounded.

[0008] The protection trigger circuit includes a first capacitor, a fourth resistor, a fifth resistor, a first electronic switch tube and a second electronic switch tube. The first end of the fourth resistor is connected to the short-circuit trigger signal terminal, the second end of the fourth resistor is connected to the control terminal of the first electronic switch tube, the first end of the fifth resistor is connected to the output terminal of the power supply circuit, the second end of the fifth resistor is connected to the control terminal of the second electronic switch tube, the second end of the first electronic switch tube is grounded, the first end of the second electronic switch tube is connected to the output terminal of the power supply circuit, the second end of the second electronic switch tube is used to be connected to the short-circuit identification signal terminal, the control terminal of the second electronic switch tube is connected to the first end of the first electronic switch tube, the first end of the first capacitor is connected to the control terminal of the first electronic switch tube, and the second end of the first capacitor is grounded.

[0009] In one embodiment, the protection trigger circuit also includes a sixth resistor and a third electronic switch tube, the first end of the sixth resistor is connected to the output end of the power supply circuit, the second end of the sixth resistor is connected to the control end of the third electronic switch tube, the first end of the third electronic switch tube is connected to the second end of the fourth resistor, the second end of the third electronic switch tube is grounded, and the first end of the fourth resistor is also connected to the short circuit identification signal end.

[0010] In one embodiment, the protection trigger circuit further includes a seventh resistor, a first end of the seventh resistor is used to be connected to the power-on reset end, and a second end of the seventh resistor is connected to the control end of the third electronic switch tube.

[0011] In one embodiment, the protection trigger circuit further includes a second capacitor, a first end of the second capacitor is connected to the second end of the sixth resistor, and a second end of the second capacitor is connected to the control end of the third electronic switch tube.

[0012] In one embodiment, the protection trigger circuit further includes an eighth resistor, a first end of the eighth resistor is connected to the control end of the third electronic switch tube, and a second end of the eighth resistor is grounded.

[0013] In one embodiment, the protection trigger circuit further includes a first current-conducting diode, wherein the anode of the first current-conducting diode is connected to the short-circuit identification signal terminal, and the cathode of the first current-conducting diode is connected to the first end of the fourth resistor.

[0014] In one embodiment, the short-circuit signal detection circuit further includes a ninth resistor, a first end of the ninth resistor is connected to the output end of the power supply circuit, and a second end of the ninth resistor is connected to the short-circuit trigger signal end.

[0015] In one embodiment, the short-circuit signal detection circuit further includes a third capacitor, a first end of the third capacitor is connected to the inverting input end of the voltage comparator, and a second end of the third capacitor is grounded.

[0016] In one embodiment, the power output circuit includes a fourth electronic switch tube and a tenth resistor, the first end of the tenth resistor is connected to the short circuit identification signal terminal, the second end of the tenth resistor is connected to the control terminal of the fourth electronic switch tube, the first end of the fourth electronic switch tube is connected to the battery enable control terminal of the power output circuit, and the second end of the fourth electronic switch tube is grounded.

[0017] A battery comprises the short-circuit protection circuit based on adjustable comparator parameters as described in any one of the above items.

[0018] Compared with the prior art, the present disclosure has at least the following advantages:

[0019] 1. The above-mentioned short-circuit protection circuit based on adjustable comparator parameters can change the sensitivity of the short-circuit protection circuit based on adjustable comparator parameters to the short-circuit current by adjusting the resistance value of the second resistor, thereby realizing flexible adjustment of the short-circuit protection current; on the other hand, by adjusting the capacitance value of the first capacitor, the response time of the short-circuit protection circuit based on adjustable comparator parameters after detecting a short circuit can be changed, thereby realizing adjustment of the delay time of the short-circuit protection, and thus making the short-circuit protection circuit based on adjustable comparator parameters adaptable to the needs of different application scenarios.

[0020] 2. The short-circuit protection circuit based on adjustable comparator parameters can achieve the function of short-circuit protection for the battery only through the voltage comparator and its supporting hardware circuit, thereby enabling the short-circuit protection circuit based on adjustable comparator parameters to avoid the risk of protection failure caused by software or processor abnormalities.

[0021] 3. The short-circuit protection circuit based on adjustable comparator parameters also has self-locking and unlocking functions. When a short circuit occurs in the circuit and the fault has not been eliminated, the short-circuit identification signal end will continue to output a high-level signal to the control end of the first electronic switch tube to keep it in the on state, thereby keeping the circuit in the short-circuit protection state; when the short-circuit fault is eliminated and the circuit is powered on again, the output end of the power supply circuit will output a high-level signal to the control end of the third electronic switch tube to turn it on and ground the short-circuit identification signal end, thereby restoring the circuit to normal working state. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present disclosure and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0023] Figure 1 A circuit diagram of a short-circuit protection circuit based on adjustable comparator parameters according to an embodiment;

[0024] Figure 2 for Figure 1 The circuit diagram of the short-circuit signal detection circuit shown;

[0025] Figure 3 for Figure 1 The circuit diagram of the protection trigger circuit shown;

[0026] Figure 4 for Figure 1 The circuit diagram of the power output circuit is shown. DETAILED DESCRIPTION

[0027] To facilitate understanding of the present disclosure, a more comprehensive description of the present disclosure will be provided below with reference to the accompanying drawings. The accompanying drawings illustrate preferred embodiments of the present disclosure. However, the present disclosure can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the disclosure.

[0028] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly attached to the other element or there may be an intermediate element. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only implementation methods.

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this disclosure pertains. The terms used herein in the specification of this disclosure are intended only to describe specific embodiments and are not intended to limit this disclosure. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0030] In order to better understand the technical solutions and beneficial effects of the present disclosure, the present disclosure is further described in detail below with reference to specific embodiments:

[0031] like Figures 1 to 4 As shown, an embodiment of the present disclosure of a short-circuit protection circuit 10 based on adjustable comparator parameters includes a power supply circuit 100, a short-circuit signal detection circuit 200, a protection trigger circuit 300 and an electric energy output circuit 400. The power supply circuit 100 is used to provide electric energy to the short-circuit signal detection circuit 200, and the electric energy output circuit 400 is used to control the battery to output electric energy.

[0032] The short-circuit signal detection circuit 200 includes a voltage comparator U15, a first resistor RN7, a second resistor RN8 and a third resistor RN5. The first end of the first resistor RN7 is used to connect to the sampling resistor short-circuit detection signal input terminal SRN-SCD, the second end of the first resistor RN7 is connected to the positive input terminal +InB of the voltage comparator U15, the output terminal OutB of the voltage comparator U15 is used to connect to the short-circuit trigger signal terminal HW-SCD, the first end of the third resistor RN5 is connected to the output terminal SC_3.3V-OUT of the power supply circuit 100, the second end of the third resistor RN5 is connected to the first end of the second resistor RN8, the first end of the second resistor RN8 is connected to the reverse input terminal -InB of the voltage comparator U15, and the second end of the second resistor RN8 is grounded.

[0033] The protection trigger circuit 300 includes a first capacitor CN8, a fourth resistor RN10, a fifth resistor RN13, a first electronic switch QN1, and a second electronic switch QN2. A first end of the fourth resistor RN10 is connected to the short-circuit trigger signal terminal HW-SCD, a second end of the fourth resistor RN10 is connected to the control terminal of the first electronic switch QN1, a first end of the fifth resistor RN13 is connected to the output terminal SC_3.3V-OUT of the power supply circuit 100, a second end of the fifth resistor RN13 is connected to the control terminal of the second electronic switch QN2, a second end of the first electronic switch QN1 is grounded, a first end of the second electronic switch QN2 is connected to the output terminal SC_3.3V-OUT of the power supply circuit 100, a second end of the second electronic switch QN2 is connected to the short-circuit identification signal terminal LATCH-ON, a control terminal of the second electronic switch QN2 is connected to the first end of the first electronic switch QN1, a first end of the first capacitor CN8 is connected to the control terminal of the first electronic switch QN1, and a second end of the first capacitor CN8 is grounded.

[0034] In this embodiment, under normal conditions, the power supply circuit 100 provides power to the short-circuit signal detection circuit 200, and the voltage comparator U15 is in a monitoring state. The voltages at the positive and negative input terminals of the voltage comparator U15 are respectively maintained in a balanced state, and the output terminal OutB of the voltage comparator U15 maintains a low output level. When a short circuit occurs in the battery, the sampling resistor short-circuit detection signal input terminal SRN-SCD will output a high-level signal, which is transmitted to the positive input terminal +InB of the voltage comparator U15 after passing through the first resistor RN7. At the same time, the reverse input terminal -InB of the voltage comparator U15 is connected to the current loop formed by the output terminal SC_3.3V-OUT of the power supply circuit 100, the third resistor RN5, the second resistor RN8 and the ground terminal, and serves as the reverse input signal of the voltage comparator U15. Then, the output terminal OutB of the voltage comparator U15 outputs a high-level signal to the short-circuit trigger signal terminal HW-SCD.

[0035] Furthermore, when the short-circuit trigger signal terminal HW-SCD receives a high-level signal, the high-level signal passes through the fourth resistor RN10 and then flows through the first capacitor CN8, causing the first capacitor CN8 to start charging. At this time, the charging process of the first capacitor CN8 plays a delay role. When the first capacitor CN8 is fully charged, its voltage increases. Since the first end of the first capacitor CN8 is connected to the control end of the first electronic switch tube QN1, the voltage at the control end of the first electronic switch tube QN1 is greater than its threshold voltage, thereby turning on the first electronic switch tube QN1. Since the control end of the second electronic switch tube QN2 is connected to the control end of the first electronic switch tube QN1, the voltage at the control end of the first electronic switch tube QN1 is greater than its threshold voltage, thereby turning on the first electronic switch tube QN1. The first end of the first electronic switch tube QN1 is connected to the first end of the second electronic switch tube QN2. After the first electronic switch tube QN1 is turned on, the voltage at the control end of the second electronic switch tube QN2 is lower than its threshold voltage, thereby turning on the second electronic switch tube QN2. The high-level signal output by the output terminal SC_3.3V-OUT of the power supply circuit 100 flows through the first end of the second electronic switch tube QN2 and then flows through the second end thereof, thereby causing the short-circuit identification signal terminal LATCH-ON to obtain a high-level signal. At the same time, the short-circuit identification signal terminal LATCH-ON pulls the battery enable control terminal VCC-EN of the power output circuit 400 to a low level, thereby stopping the power output circuit 400 from outputting power.

[0036] The above-mentioned short-circuit protection circuit 10 based on adjustable comparator parameters can change the sensitivity of the short-circuit protection circuit 10 based on adjustable comparator parameters to the short-circuit current by adjusting the resistance value of the second resistor RN8, thereby realizing flexible adjustment of the short-circuit protection current; on the other hand, by adjusting the capacitance value of the first capacitor CN8, the response time of the short-circuit protection circuit 10 based on adjustable comparator parameters after detecting a short circuit can be changed, thereby realizing adjustment of the delay time of the short-circuit protection, and thus making the short-circuit protection circuit 10 based on adjustable comparator parameters able to adapt to the needs of different application scenarios; and the short-circuit protection circuit 10 based on adjustable comparator parameters can realize the function of short-circuit protection of the battery only through the voltage comparator U15 and its supporting hardware circuit, thereby making the short-circuit protection circuit 10 based on adjustable comparator parameters able to avoid the risk of protection failure caused by software or processor abnormalities.

[0037] In another embodiment, the first electronic switch tube QN1 is an NPN-type transistor, the first end of the first electronic switch tube QN1 is the collector of the NPN-type transistor, the second end of the first electronic switch tube QN1 is the emitter of the NPN-type transistor, and the control end of the first electronic switch tube QN1 is the base of the NPN-type transistor; the second electronic switch tube QN2 is a PNP-type transistor, the first end of the second electronic switch tube QN2 is the emitter of the PNP-type transistor, the second end of the second electronic switch tube QN2 is the collector of the PNP-type transistor, and the control end of the second electronic switch tube QN2 is the base of the PNP-type transistor.

[0038] like Figure 3As shown, in one embodiment, the protection trigger circuit 300 further includes a sixth resistor RN39 and a third electronic switch tube QN3. The first end of the sixth resistor RN39 is connected to the output terminal SC_3.3V-OUT of the power supply circuit 100, the second end of the sixth resistor RN39 is connected to the control terminal of the third electronic switch tube QN3, the first end of the third electronic switch tube QN3 is connected to the second end of the fourth resistor RN10, the second end of the third electronic switch tube QN3 is grounded, and the first end of the fourth resistor RN10 is also connected to the short-circuit identification signal terminal LATCH-ON. In this embodiment, when the short-circuit identification signal terminal LATCH-ON receives a high-level signal, the short-circuit identification signal terminal LATCH-ON continues to output current and flows through the control terminal of the first electronic switch QN1 through the fourth resistor RN10, causing the voltage at the control terminal of the first electronic switch QN1 to be greater than its threshold voltage. As a result, the first electronic switch QN1 remains in an on state, thereby enabling the short-circuit protection circuit 10 based on adjustable comparator parameters to have a self-locking function after a short circuit occurs, preventing the circuit from accidentally resuming operation before the short-circuit fault is completely eliminated. When the short-circuit fault is eliminated and the circuit is powered on again, the control terminal of the third electronic switch QN3 is connected to the output terminal of the power supply circuit 100, so that the voltage at the control terminal of the third electronic switch QN3 is greater than its threshold voltage, thereby turning on the third electronic switch QN3. The high-level signal at the short-circuit identification signal terminal LATCH-ON flows through the first terminal of the third electronic switch QN3 and is then grounded through the second terminal of the third electronic switch QN3, thereby resuming normal operation of the short-circuit protection circuit 10 based on adjustable comparator parameters.

[0039] In another embodiment, the third electronic switch tube QN3 is an NPN transistor, the first end of the third electronic switch tube QN3 is the collector of the NPN transistor, the second end of the third electronic switch tube QN3 is the emitter of the NPN transistor, and the control end of the third electronic switch tube QN3 is the base of the NPN transistor.

[0040] like Figure 3As shown, in one embodiment, the protection trigger circuit further includes a seventh resistor RN34, a first end of the seventh resistor RN34 being connected to the power-on reset terminal LATCH-OFF, and a second end of the seventh resistor RN34 being connected to the control terminal of the third electronic switch QN3. In this embodiment, when the circuit is powered on again after the fault in the circuit is eliminated, the power-on reset terminal LATCH-OFF outputs a high-level signal with a duration of one second to the control terminal of the third electronic switch QN3, causing the voltage at the control terminal of the third electronic switch QN3 to exceed its threshold voltage, thereby turning on the third electronic switch QN3. The short-circuit identification signal terminal LATCH-ON and the short-circuit trigger signal terminal HW-SCD are connected to the ground terminal through the third electronic switch QN3 and pulled to a low level, thereby preventing the high-level signals at the short-circuit identification signal terminal LATCH-ON and the short-circuit trigger signal terminal HW-SCD from falsely triggering the protection mechanism.

[0041] like Figure 3 As shown, in one embodiment, the protection trigger circuit 300 further includes a second capacitor CN21, wherein a first end of the second capacitor CN21 is connected to the second end of the sixth resistor RN39, and a second end of the second capacitor CN21 is connected to the control end of the third electronic switch QN3. In this embodiment, because the capacitor has the ability to store charge, when the third electronic switch QN3 rapidly switches states, the current at its control end may suddenly change, and abnormal current fluctuations may easily occur during this process. The second capacitor CN21 can quickly absorb or release charge, slowing down the current change in the circuit, thereby stabilizing the voltage at its control end, and thereby ensuring that the third electronic switch QN3 can maintain stable operation.

[0042] like Figure 3 As shown, in one embodiment, the protection trigger circuit 300 further includes an eighth resistor RN15. A first end of the eighth resistor RN15 is connected to the control terminal of the third electronic switch QN3, and a second end of the eighth resistor RN15 is grounded. In this embodiment, the eighth resistor RN15 can limit the current flowing through the control terminal of the third electronic switch QN3, preventing excessive transient current from damaging the control terminal of the third electronic switch QN3. Furthermore, the eighth resistor RN15 and the second capacitor CN21 form an RC filter circuit, which helps filter out high-frequency interference signals in the circuit, thereby ensuring stable operation of the third electronic switch QN3.

[0043] like Figure 3As shown, in one embodiment, the protection trigger circuit 300 further includes a first current-steering diode DN1. The anode of the first current-steering diode DN1 is connected to the short-circuit identification signal terminal LATCH-ON, and the cathode of the first current-steering diode DN1 is connected to the first end of the fourth resistor RN10. In this embodiment, because the diode has unidirectional conductivity, it only allows current to flow from the anode to the cathode. Therefore, when current flows from the short-circuit identification signal terminal LATCH-ON and flows through the first current-steering diode DN1 and the fourth resistor RN10, the first current-steering diode DN1 prevents the current from flowing back to the short-circuit identification signal terminal LATCH-ON, thereby ensuring the normal operation of the protection trigger circuit 300.

[0044] like Figure 2 As shown, in one embodiment, the short-circuit signal detection circuit 200 further includes a ninth resistor RN6, wherein a first end of the ninth resistor RN6 is connected to the output terminal SC_3.3V-OUT of the power supply circuit 100, and a second end of the ninth resistor RN6 is connected to the short-circuit trigger signal terminal HW-SCD. In this embodiment, since the ninth resistor RN6 functions as a pull-up resistor, its two ends are respectively connected to the output terminal SC_3.3V-OUT of the power supply circuit 100 and the short-circuit trigger signal terminal HW-SCD. When no short circuit occurs, current flows through the output terminal of the power supply circuit 100 and the ninth resistor RN6 and then flows through the short-circuit trigger signal terminal HW-SCD, so that the ninth resistor RN6 provides a stable reference voltage for the short-circuit trigger signal terminal HW-SCD. At the same time, the ninth resistor RN6 helps reduce noise interference on the short-circuit trigger signal terminal HW-SCD, thereby improving the stability of the short-circuit trigger signal terminal HW-SCD.

[0045] like Figure 2 As shown, in one embodiment, the short-circuit signal detection circuit 200 further includes a third capacitor CN5, a first end of the third capacitor CN5 being connected to the inverting input terminal -InB of the voltage comparator U15, and a second end of the third capacitor CN5 being grounded. In this embodiment, the capacitor has the ability to store charge. When the voltage at the inverting input terminal -InB of the voltage comparator U15 changes, the third capacitor CN5 will slow down the change in the voltage difference between its two ends by charging and discharging. When the input signal has high-frequency noise, the capacitor will gradually absorb and smooth out these high-frequency components through the charging and discharging process, thereby effectively filtering out the noise and thereby improving the stability of the short-circuit signal detection circuit 200.

[0046] like Figure 4As shown, in one embodiment, the power output circuit includes a fourth electronic switch tube QN5 and a tenth resistor RN23. A first end of the tenth resistor RN23 is connected to the short-circuit identification signal terminal LATCH-ON, a second end of the tenth resistor RN23 is connected to the control terminal of the fourth electronic switch tube QN5, a first end of the fourth electronic switch tube QN5 is connected to the battery enable control terminal VCC-EN of the power output circuit 400, and a second end of the fourth electronic switch tube QN5 is grounded. In this embodiment, when a short circuit fault occurs in the circuit, the short circuit identification signal terminal LATCH-ON will obtain a high-level signal. The high-level signal output by the short circuit identification signal terminal LATCH-ON is then transmitted to the control terminal of the fourth electronic switch transistor QN5 through the tenth resistor RN23, causing the voltage at the control terminal of the fourth electronic switch transistor QN5 to exceed its threshold voltage, thereby turning on the fourth electronic switch transistor QN5. Since the battery enable control terminal VCC-EN of the power output circuit 400 is connected to the first terminal of the fourth electronic switch transistor QN5, the battery enable control terminal VCC-EN of the power output circuit 400 is connected to the ground terminal through the fourth electronic switch transistor QN5, thereby pulling the battery enable control terminal VCC-EN of the power output circuit 400 to a low level, thereby stopping the power output circuit 400 from outputting power.

[0047] In another embodiment, the fourth electronic switch tube QN5 is an NPN transistor, the first end of the fourth electronic switch tube QN5 is the collector of the NPN transistor, the second end of the fourth electronic switch tube QN5 is the emitter of the NPN transistor, and the control end of the fourth electronic switch tube QN5 is the base of the NPN transistor.

[0048] A battery includes any of the above-mentioned short-circuit protection circuits 10 with adjustable comparator parameters. In this embodiment, under normal conditions, the power supply circuit 100 provides power to the short-circuit signal detection circuit 200, and the voltage comparator U15 is in a monitoring state. The voltages at the positive and negative input terminals of the voltage comparator U15 are respectively maintained in a balanced state, and the output terminal OutB of the voltage comparator U15 maintains a low output level. When a short circuit occurs in the battery, the sampling resistor short-circuit detection signal input terminal SRN-SCD will output a high-level signal, which is then transmitted to the positive input terminal +InB of the voltage comparator U15 after passing through the first resistor RN7. At the same time, the negative input terminal -InB of the voltage comparator U15 is connected to the current loop formed by the output terminal SC_3.3V-OUT of the power supply circuit 100, the third resistor RN5, the second resistor RN8, and the ground terminal, and serves as the negative input signal of the voltage comparator U15. Then, the output terminal OutB of the voltage comparator U15 outputs a high-level signal to the short-circuit trigger signal terminal HW-SCD. Furthermore, when the short-circuit trigger signal terminal HW-SCD receives a high-level signal, the high-level signal passes through the fourth resistor RN10 and then flows through the first capacitor CN8, causing the first capacitor CN8 to start charging. At this time, the charging process of the first capacitor CN8 plays a delay role. When the first capacitor CN8 is fully charged, its voltage increases. Since the first end of the first capacitor CN8 is connected to the control end of the first electronic switch tube QN1, the voltage at the control end of the first electronic switch tube QN1 is greater than its threshold voltage, thereby turning on the first electronic switch tube QN1. Since the control end of the second electronic switch tube QN2 is connected to the control end of the first electronic switch tube QN1, the voltage at the control end of the first electronic switch tube QN1 is greater than its threshold voltage, thereby turning on the first electronic switch tube QN1. The first end of the first electronic switch tube QN1 is connected to the first end of the second electronic switch tube QN2. After the first electronic switch tube QN1 is turned on, the voltage at the control end of the second electronic switch tube QN2 is lower than its threshold voltage, thereby turning on the second electronic switch tube QN2. The high-level signal output by the output terminal SC_3.3V-OUT of the power supply circuit 100 flows through the first end of the second electronic switch tube QN2 and then flows through the second end thereof, thereby causing the short-circuit identification signal terminal LATCH-ON to obtain a high-level signal. At the same time, the short-circuit identification signal terminal LATCH-ON pulls the battery enable control terminal VCC-EN of the power output circuit 400 to a low level, thereby stopping the power output circuit 400 from outputting power.

[0049] Compared with the prior art, the present disclosure has at least the following advantages:

[0050] 1. The above-mentioned short-circuit protection circuit 10 with adjustable comparator parameters can change the sensitivity of the short-circuit protection circuit 10 with adjustable comparator parameters to the short-circuit current by adjusting the resistance value of the second resistor RN8, thereby realizing flexible adjustment of the short-circuit protection current; on the other hand, by adjusting the capacitance value of the first capacitor CN8, the response time of the short-circuit protection circuit 10 with adjustable comparator parameters after detecting a short circuit can be changed, thereby realizing adjustment of the delay time of the short-circuit protection, and thus making the short-circuit protection circuit 10 with adjustable comparator parameters adaptable to the needs of different application scenarios.

[0051] 2. The short-circuit protection circuit 10 based on adjustable comparator parameters can realize the function of short-circuit protection of the battery only through the voltage comparator U15 and its supporting hardware circuit, thereby enabling the short-circuit protection circuit 10 based on adjustable comparator parameters to avoid the risk of protection failure caused by software or processor abnormalities.

[0052] 3. The short-circuit protection circuit 10 with adjustable comparator parameters also has self-locking and unlocking functions. When a short circuit occurs in the circuit and the fault has not been eliminated, the short-circuit identification signal terminal LATCH-ON will continuously output a high-level signal to the control terminal of the first electronic switch tube QN1 to keep it in the on state, thereby maintaining the circuit in the short-circuit protection state. When the short-circuit fault is eliminated and the circuit is powered on again, the output terminal SC_3.3V-OUT of the power supply circuit 100 will output a high-level signal to the control terminal of the third electronic switch tube QN3 to turn it on and ground the short-circuit identification signal terminal LATCH-ON, thereby restoring the circuit to normal operation.

[0053] The above-described embodiments merely represent several implementation methods of the present disclosure. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the disclosed patent. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the scope of the present disclosure, all of which fall within the scope of protection of the present disclosure. Therefore, the scope of protection of the disclosed patent shall be determined by the appended claims.

Claims

1. A short-circuit protection circuit based on an adjustable comparator parameter, comprising a power supply circuit, a short-circuit signal detection circuit, a protection trigger circuit, and an electric energy output circuit, wherein the power supply circuit is used to provide electric energy to the short-circuit signal detection circuit, and the electric energy output circuit is used to control the output of electric energy from a battery, characterized in that: The short-circuit signal detection circuit includes a voltage comparator, a first resistor, a second resistor, and a third resistor, wherein the first end of the first resistor is used to be connected to the sampling resistor short-circuit detection signal input terminal, the second end of the first resistor is connected to the positive input terminal of the voltage comparator, the output terminal of the voltage comparator is used to be connected to the short-circuit trigger signal terminal, the first end of the third resistor is connected to the output terminal of the power supply circuit, the second end of the third resistor is connected to the first end of the second resistor, the first end of the second resistor is connected to the negative input terminal of the voltage comparator, and the second end of the second resistor is grounded; The protection trigger circuit includes a first capacitor, a fourth resistor, a fifth resistor, a first electronic switch tube and a second electronic switch tube. The first end of the fourth resistor is connected to the short-circuit trigger signal terminal, the second end of the fourth resistor is connected to the control terminal of the first electronic switch tube, the first end of the fifth resistor is connected to the output terminal of the power supply circuit, the second end of the fifth resistor is connected to the control terminal of the second electronic switch tube, the second end of the first electronic switch tube is grounded, the first end of the second electronic switch tube is connected to the output terminal of the power supply circuit, the second end of the second electronic switch tube is used to be connected to the short-circuit identification signal terminal, the control terminal of the second electronic switch tube is connected to the first end of the first electronic switch tube, the first end of the first capacitor is connected to the control terminal of the first electronic switch tube, and the second end of the first capacitor is grounded.

2. The short-circuit protection circuit based on adjustable comparator parameters according to claim 1, characterized in that: The protection trigger circuit also includes a sixth resistor and a third electronic switch tube. The first end of the sixth resistor is connected to the output end of the power supply circuit, the second end of the sixth resistor is connected to the control end of the third electronic switch tube, the first end of the third electronic switch tube is connected to the second end of the fourth resistor, the second end of the third electronic switch tube is grounded, and the first end of the fourth resistor is also connected to the short circuit identification signal end.

3. The short-circuit protection circuit based on adjustable comparator parameters according to claim 2, characterized in that: The protection trigger circuit further includes a seventh resistor, a first end of the seventh resistor is used to be connected to the power-on reset end, and a second end of the seventh resistor is connected to the control end of the third electronic switch tube.

4. The short-circuit protection circuit based on adjustable comparator parameters according to claim 2, characterized in that: The protection trigger circuit further includes a second capacitor, a first end of the second capacitor is connected to the second end of the sixth resistor, and a second end of the second capacitor is connected to the control end of the third electronic switch tube.

5. The short-circuit protection circuit based on adjustable comparator parameters according to claim 2, characterized in that: The protection trigger circuit further includes an eighth resistor, a first end of the eighth resistor is connected to the control end of the third electronic switch tube, and a second end of the eighth resistor is grounded.

6. The short-circuit protection circuit based on adjustable comparator parameters according to claim 2, characterized in that: The protection trigger circuit further includes a first current-conducting diode, wherein an anode of the first current-conducting diode is connected to the short-circuit identification signal terminal, and a cathode of the first current-conducting diode is connected to the first end of the fourth resistor.

7. The short-circuit protection circuit based on adjustable comparator parameters according to claim 1, characterized in that: The short-circuit signal detection circuit further includes a ninth resistor, a first end of the ninth resistor being connected to the output end of the power supply circuit, and a second end of the ninth resistor being connected to the short-circuit trigger signal end.

8. The short-circuit protection circuit based on adjustable comparator parameters according to claim 7, characterized in that: The short-circuit signal detection circuit further includes a third capacitor, a first end of the third capacitor is connected to the inverting input end of the voltage comparator, and a second end of the third capacitor is grounded.

9. The short-circuit protection circuit based on adjustable comparator parameters according to claim 1, characterized in that: The power output circuit includes a fourth electronic switch tube and a tenth resistor, a first end of the tenth resistor is connected to the short circuit identification signal terminal, a second end of the tenth resistor is connected to the control terminal of the fourth electronic switch tube, a first end of the fourth electronic switch tube is connected to the battery enable control terminal of the power output circuit, and a second end of the fourth electronic switch tube is grounded.

10. A battery, characterized in that: The short-circuit protection circuit comprises the comparator parameter adjustable short-circuit protection circuit according to any one of claims 1 to 9.

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