Hysteresis comparator

Abstract

The utility model discloses a hysteresis comparator. The hysteresis comparator comprises an operational amplifier, a voltage dividing unit, a positive feedback network, a compensation unit and at least two voltage input units, the first end of the positive feedback network is connected with the in-phase input end of the operational amplifier and connected with the first end of the compensation unit, the second end of the positive feedback network is connected with the output end of the operational amplifier, the second end of the compensation unit is connected with the first end of the voltage dividing unit, the second end of the voltage dividing unit is connected with reference voltage, and the third end of the voltage dividing unit is grounded. The reverse input end of the operational amplifier is connected with the output ends of the at least two voltage input units; the operational amplifier is used for comparing the voltage of the non-inverting input end with the voltage of the inverting input end and outputting a comparison result; the voltage dividing unit is used for providing voltage for the in-phase input end of the operational amplifier; the compensation unit is used for compensating the voltage of the in-phase input end. According to the embodiment of the utility model, the stability and reliability of the hysteresis comparator can be improved.

Description

Technical Field

[0001] The utility model relates to the technical field of power electronics, in particular to a hysteresis comparator. Background Art

[0002] When the input signal of the hysteresis comparator is a multi-channel signal multiplexed using a diode, the influence of the diode's forward voltage drop needs to be considered when designing the protection threshold of the hysteresis comparator. However, the diode's forward voltage drop is greatly affected by current or temperature changes, resulting in changes in the forward voltage drop, which can cause the hysteresis comparator to falsely trigger protection or not trigger protection, resulting in poor stability and reliability. Utility Model Content

[0003] The utility model provides a hysteresis comparator to improve the stability and reliability of the hysteresis comparator.

[0004] A hysteresis comparator provided according to the utility model includes: an operational amplifier, a voltage dividing unit, a positive feedback network, a compensation unit and at least two voltage input units;

[0005] The first end of the positive feedback network is connected to the in-phase input end of the operational amplifier and to the first end of the compensation unit, the second end of the positive feedback network is connected to the output end of the operational amplifier, the second end of the compensation unit is connected to the first end of the voltage divider unit, the second end of the voltage divider unit is connected to a reference voltage, the third end of the voltage divider unit is grounded, the inverting input end of the operational amplifier is connected to the output ends of at least two voltage input units, the input ends of the at least two voltage input units are connected to an input voltage, and at least two of the voltage input units are connected in parallel;

[0006] The operational amplifier is used to compare the voltage of the in-phase input terminal and the voltage of the inverting input terminal, and output the comparison result; the voltage divider unit is used to provide the voltage of the in-phase input terminal of the operational amplifier; and the compensation unit is used to compensate the voltage of the in-phase input terminal.

[0007] Optionally, the voltage dividing unit includes a first resistor and a second resistor;

[0008] The first end of the first resistor is connected to the reference voltage, the second end of the first resistor is connected to the second end of the compensation unit and to the first end of the second resistor, and the second end of the second resistor is grounded.

[0009] Optionally, the positive feedback network includes a third resistor;

[0010] A first end of the third resistor is connected to the non-inverting input terminal of the operational amplifier, and a second end of the third resistor is connected to the output terminal of the operational amplifier.

[0011] Optionally, the compensation unit includes a first diode and a second diode; at least two of the voltage input units each include a third diode;

[0012] The first pole of the first diode is connected to the first end of the voltage divider unit, the second pole of the first diode is connected to the non-inverting input terminal of the operational amplifier and to the first pole of the second diode, and the second pole of the second diode is connected to the first end of the voltage divider unit; the first pole of the third diode is connected to the input voltage, and the second pole of the third diode is connected to the inverting input terminal of the operational amplifier.

[0013] Optionally, the model of the first diode, the model of the second diode, and the model of the third diode are all the same.

[0014] Optionally, the hysteresis comparator further comprises: a fourth resistor;

[0015] The first end of the fourth resistor is connected to the reference voltage, and the second end of the fourth resistor is connected to the output end of the operational amplifier.

[0016] Optionally, the hysteresis comparator further comprises: a filtering module;

[0017] The first end of the filter module is connected to the output end of the operational amplifier, the second end of the filter module is grounded, and the third end of the filter module is used to output the comparison result.

[0018] Optionally, the filtering module includes a fifth resistor and a first capacitor;

[0019] The first end of the fifth resistor is connected to the output end of the operational amplifier, the second end of the fifth resistor is connected to the first end of the first capacitor, and the second end of the first capacitor is grounded;

[0020] Among them, the first end of the fifth resistor serves as the first end of the filter module, the second end of the first capacitor serves as the second end of the filter module, and the connection end of the second end of the fifth resistor and the first end of the first capacitor serves as the third end of the filter module.

[0021] Optionally, the hysteresis comparator further comprises: a protection unit;

[0022] A first terminal of the protection unit is connected to the inverting input terminal of the operational amplifier, and a second terminal of the protection unit is grounded.

[0023] Optionally, the protection unit includes a sixth resistor;

[0024] A first end of the sixth resistor is connected to the inverting input end of the operational amplifier, and a second end of the sixth resistor is grounded.

[0025] The technical solution of the embodiment of the utility model is to set a compensation unit at the non-inverting input terminal of the operational amplifier. When the hysteresis comparator is working and the temperature changes, the compensation unit can further compensate the voltage of the non-inverting input terminal, so that the voltage of the non-inverting input terminal and the voltage of the reverse input terminal of the operational amplifier have the same change trend, so that when the voltage of the reverse input terminal is close to the voltage of the non-inverting input terminal, the influence of the voltage drop change at the reverse input terminal caused by the temperature change can be avoided, and the hysteresis comparator can be prevented from falsely triggering protection and not protecting, thereby improving the stability and reliability of the hysteresis comparator.

[0026] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present utility model, nor are they intended to limit the scope of the present utility model. Other features of the present utility model will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0028] Figure 1 A structural schematic diagram of a hysteresis comparator provided for related technology;

[0029] Figure 2 A schematic diagram of the structure of a hysteresis comparator provided in an embodiment of the utility model;

[0030] Figure 3 A schematic diagram of the structure of another hysteresis comparator provided by an embodiment of the utility model;

[0031] Figure 4 A schematic diagram of the structure of another hysteresis comparator provided by an embodiment of the utility model;

[0032] Figure 5 A schematic diagram of the structure of another hysteresis comparator provided by an embodiment of the utility model;

[0033] Figure 6 is an equivalent circuit for calculating high threshold voltage;

[0034] Figure 7 is an equivalent circuit for calculating low threshold voltage;

[0035] Figure 8 A schematic diagram of the structure of another hysteresis comparator provided in an embodiment of the utility model. DETAILED DESCRIPTION

[0036] In order to enable those skilled in the art to better understand the solution of the utility model, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is only a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the utility model.

[0037] It should be noted that the terms "first", "second", etc. in the specification and claims of the utility model and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the utility model described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0038] Figure 1 A schematic diagram of a hysteresis comparator provided for related technology, reference Figure 1 The hysteresis comparator includes an amplifier U11, a resistor R11, a resistor R22, a resistor R33, a resistor R44 and at least two voltage input units, the at least two voltage input units are connected in parallel, and any voltage input unit includes a diode.

[0039] Among them, the first end of the resistor R11 and the first end of the resistor R44 are connected to the reference voltage Vref1, the second end of the resistor R11 is connected to the first end of the resistor R22 and to the in-phase input terminal of the amplifier U11, the second end of the resistor R22 is grounded, the resistor R33 is connected between the in-phase input terminal and the output terminal of the amplifier U11, and the second end of the resistor R44 is connected to the output terminal of the amplifier U11.

[0040] Next, the reverse input terminal of the hysteresis comparator is connected to two voltage input units as an example for explanation. Different voltage input units have different input voltages. For example, the input voltage of one voltage input unit is Vin11, and the input voltage of another voltage input unit is Vin21. Moreover, since the voltage input unit includes a diode, at the same time, the larger voltage of Vin11 and Vin21 can be input to the reverse input terminal of the operational amplifier. Exemplarily, if Vin11=3.3V, Vin21=5V, the input voltage of the reverse input terminal of the amplifier U1 is 5V. It can be understood that when multiple (greater than 2) voltage input units are included, when the input voltages of the multiple voltage input units are different, the working principle and process are the same.

[0041] Among them, the hysteresis comparator introduces positive feedback through the resistor R33, thereby generating the threshold voltage of the hysteresis comparator, and the threshold voltage of the hysteresis comparator is related to the voltage of the non-inverting input terminal of the hysteresis comparator, so the threshold voltage of the hysteresis comparator is related to the reference voltage Vref1, that is, the threshold voltage of the hysteresis comparator can be calculated based on the reference voltage Vref1. The voltage of the reverse input terminal of the hysteresis comparator is related to the input voltage of the voltage input unit. It can be understood that the threshold voltage of the hysteresis comparator includes a high threshold voltage and a low threshold voltage. The high threshold voltage can be understood as when the voltage of the reverse input terminal changes from low to high and exceeds this threshold, the output voltage of the output terminal of the hysteresis comparator is a high level; the low threshold voltage can be understood as when the voltage of the reverse input terminal changes from high to low and is lower than this threshold, the output voltage of the output terminal of the hysteresis comparator is a low level.

[0042] Specifically, when the output of the hysteresis comparator is at a high level, the output is pulled up to the reference voltage Vref1 through the resistor R44. At this time, the equivalent circuit is that the resistors R33 and R44 are connected in series, connected in parallel with the resistor R11, and then connected in series with the resistor R22, and then: Then we can get V x1 , which is the high threshold voltage of the hysteresis comparator. Among them, r 11 is the resistance value of resistor R11, r 22 is the resistance value of resistor R22, r 33 is the resistance value of resistor R33, r 44 is the resistance value of resistor R44.

[0043] When the output of the hysteresis comparator is at a low level, the equivalent circuit at this time is resistors R22 and R33 connected in parallel, and then connected in series with resistor R11, and then it can be obtained: Then we can get V x2 , which is the low threshold voltage of the hysteresis comparator. 11 is the resistance value of resistor R11, r 22is the resistance value of resistor R22, r 33 is the resistance value of resistor R33.

[0044] Therefore, the calculation of the high threshold voltage and the low threshold voltage of the hysteresis comparator is only related to the partial resistance connected to the in-phase input terminal, and has nothing to do with other parameters. When the reverse input terminal is a multiplexed input and multiplexing is performed through a diode, the voltage drop of the diode cannot be ignored in an environment with large temperature changes, which can easily cause the hysteresis comparator to falsely trigger the protection or not trigger the protection.

[0045] In order to avoid the problems existing in the above hysteresis comparator, an embodiment of the utility model provides a hysteresis comparator, and the structure of the hysteresis comparator is described in detail below.

[0046] Figure 2 A schematic diagram of a hysteresis comparator provided by an embodiment of the utility model, referring to Figure 2 The hysteresis comparator includes an operational amplifier U1, a voltage divider unit 10, a positive feedback network 20, a compensation unit 30 and at least two voltage input units; the first end of the positive feedback network 20 is connected to the non-inverting input terminal IN+ of the operational amplifier U1, and is connected to the first end of the compensation unit 30, the second end of the positive feedback network 20 is connected to the output end of the operational amplifier U1, the second end of the compensation unit 30 is connected to the first end of the voltage divider unit 10, the second end of the voltage divider unit 10 is connected to the reference voltage Vref, the third end of the voltage divider unit 10 is grounded, the reverse input terminal IN- of the operational amplifier U1 is connected to the output ends of the at least two voltage input units, the input ends of the at least two voltage input units are connected to the input voltage, and the at least two voltage input units are connected in parallel; the operational amplifier U1 is used to compare the voltage of the non-inverting input terminal IN+ and the voltage of the reverse input terminal IN-, and output the comparison result Vout; the voltage divider unit 10 is used to provide the voltage of the non-inverting input terminal IN+ of the operational amplifier U1; the compensation unit 30 is used to compensate the voltage of the non-inverting input terminal IN+.

[0047] Among them, the positive feedback network 20 is used for fast switching of the comparison result Vout; the comparison result Vout can be specifically understood as, when the voltage of the in-phase input terminal IN+ is greater than the voltage of the inverting input terminal IN-, the comparison result Vout output by the operational amplifier U1 is a high level; when the voltage of the in-phase input terminal IN+ is less than the voltage of the inverting input terminal IN-, the comparison result Vout output by the operational amplifier U1 is a low level. The at least two voltage input units can exemplarily include two voltage input units, namely a first voltage input unit 41 and a second voltage input unit 42, the input voltage of the first voltage input unit 41 is Vin1, and the input voltage of the second voltage input unit 42 is Vin2.

[0048] Specifically, since the compensation unit 30 is connected between the voltage divider unit 10 and the non-inverting input terminal IN+ of the operational amplifier U1, and is connected to the positive feedback network 20, when calculating the high threshold voltage or the low threshold voltage of the hysteresis comparator, the compensation unit 30 will participate in the calculation of the threshold voltage, and can further compensate for the voltage of the non-inverting input terminal IN+ of the operational amplifier. Exemplarily, when the input voltage Vin1 of the first voltage input unit 41 is large, the voltage input to the reverse input terminal IN- of the operational amplifier U1 is Vin1. When the input voltage Vin1 is affected by temperature and the voltage drop changes greatly, that is, when the voltage drop of the reverse input terminal IN- of the operational amplifier changes greatly, the voltage of the non-inverting input terminal IN+ of the operational amplifier U1 can be compensated by the compensation unit 30, thereby offsetting the influence of the voltage drop of the reverse input terminal IN-.

[0049] The technical solution of the embodiment of the utility model is to set a compensation unit at the non-inverting input terminal of the operational amplifier. When the hysteresis comparator is working and the temperature changes, the compensation unit can further compensate the voltage of the non-inverting input terminal, so that the voltage of the non-inverting input terminal and the voltage of the reverse input terminal of the operational amplifier have the same change trend, so that when the voltage of the reverse input terminal is close to the voltage of the non-inverting input terminal, the influence of the voltage drop change at the reverse input terminal caused by the temperature change can be avoided, and the hysteresis comparator can be prevented from falsely triggering protection and not protecting, thereby improving the stability and reliability of the hysteresis comparator.

[0050] Figure 3 A schematic diagram of another hysteresis comparator provided by an embodiment of the utility model, referring to Figure 3 On the basis of the above embodiment, the voltage dividing unit 10 includes a first resistor R1 and a second resistor R2; the first end of the first resistor R1 is connected to the reference voltage Vref, the second end of the first resistor R1 is connected to the second end of the compensation unit 30, and is connected to the first end of the second resistor R2, and the second end of the second resistor R2 is grounded.

[0051] Specifically, the first resistor R1 and the second resistor R2 are used to participate in the calculation of the high threshold voltage and the low threshold voltage of the hysteresis comparator. And by setting the first resistor R1 and the second resistor R2, the hysteresis comparator can adapt to input signals in different ranges, and by adjusting the voltage division ratio, the comparator can work normally in different input voltage ranges.

[0052] Optionally, continue to refer to Figure 3 The positive feedback network 30 includes a third resistor R3; a first end of the third resistor R3 is connected to the in-phase input terminal IN+ of the operational amplifier U1, and a second end of the third resistor R3 is connected to the output terminal of the operational amplifier U1.

[0053] Specifically, the third resistor R3 is used to participate in the calculation of the high threshold voltage and the low threshold voltage of the hysteresis comparator. And the third resistor R3 is also used to enhance the hysteresis characteristics of the hysteresis comparator, so that when the voltage of the reverse input terminal IN- of the operational amplifier U1 transitions from a low level to a high level or from a high level to a low level, the comparison result Vout outputted by the output terminal will not switch immediately, but will switch after reaching a certain threshold. Through this setting, the stability and anti-interference ability of the hysteresis comparator can be improved.

[0054] Figure 4 A schematic diagram of another hysteresis comparator provided by an embodiment of the utility model, referring to Figure 4 On the basis of the above embodiments, the compensation unit 30 includes a first diode D1 and a second diode D2; at least two voltage input units each include a third diode; a first pole of the first diode D1 is connected to a first end of the voltage divider unit 10, a second pole of the first diode D1 is connected to a non-inverting input terminal IN+ of the operational amplifier U1, and is connected to a first pole of the second diode D2, a second pole of the second diode D2 is connected to a first end of the voltage divider unit 10; a first pole of the third diode is connected to an input voltage, and a second pole of the third diode is connected to an inverting input terminal IN- of the operational amplifier U1.

[0055] Next, at least two voltage input units include three voltage input units as an example for explanation, the three voltage input units are respectively a first voltage input unit 41, a second voltage input unit 42 and a third voltage input unit 43, and the input voltage of the first voltage input unit 41 is Vin1, the input voltage of the second voltage input unit 42 is Vin2, the input voltage of the third voltage input unit 43 is Vin3, and the first voltage input unit 41, the second voltage input unit 42 and the third voltage input unit 43 all include a third diode D3. Similarly, at any time, the larger input voltage among the first voltage input unit 41, the second voltage input unit 42 and the third voltage input unit 43 is input to the reverse input terminal IN- of the operational amplifier U1.

[0056] Specifically, when the input voltages of the first voltage input unit 41, the second voltage input unit 42, and the third voltage input unit 43 are input simultaneously, the input voltages are in an "OR" relationship due to the presence of the third diode D3. In addition, the first diode D1 and the second diode D2 are connected in reverse parallel between the voltage divider unit 10 and the positive feedback network 20, so that the first diode D1 and the second diode D2 can participate in the calculation of the high threshold voltage and the low threshold voltage of the hysteresis comparator, and thus, the voltage drop change caused by the third diode D3 in the voltage input unit due to the influence of temperature can be offset.

[0057] Optionally, continue to refer to Figure 4The model of the first diode D1, the model of the second diode D2, and the model of the third diode D3 are all the same.

[0058] Specifically, since the model of the first diode D1, the model of the second diode D2, and the model of the third diode D3 are all the same, under the same conditions, the voltage drops of the first diode D1, the second diode D2, and the third diode D3 are almost the same, thereby offsetting the voltage drop change of the third diode D3 in the voltage input unit caused by the influence of temperature.

[0059] The technical solution of the embodiment of the utility model can participate in the calculation of the high threshold voltage and the low threshold voltage of the hysteresis comparator by setting the first diode and the second diode connected in reverse parallel, that is, it can compensate the voltage of the non-inverting input terminal. At the same time, by setting the model of the first diode, the model of the second diode, and the model of the third diode to be the same, the voltage of the non-inverting input terminal and the voltage of the reverse input terminal of the operational amplifier have the same change trend, so that when the voltage of the reverse input terminal is close to the voltage of the non-inverting input terminal, the influence caused by the change of the voltage drop at the reverse input terminal caused by the temperature change can be avoided, and the hysteresis comparator can be prevented from falsely triggering protection and non-protection, thereby improving the stability and reliability of the hysteresis comparator.

[0060] Figure 5 A schematic diagram of another hysteresis comparator provided by an embodiment of the utility model, referring to Figure 5 On the basis of the above embodiments, the hysteresis comparator further includes: a fourth resistor R4; a first end of the fourth resistor R4 is connected to the reference voltage Vref, and a second end of the fourth resistor R4 is connected to the output end of the operational amplifier U1.

[0061] Specifically, the fourth resistor R4 is used to participate in the calculation of the high threshold voltage and the low threshold voltage of the hysteresis comparator. Exemplarily, the high threshold voltage calculation process of the hysteresis comparator is:

[0062] Figure 6 For an equivalent circuit to calculate the high threshold voltage, refer to Figure 6 Based on the above embodiments, the equivalent circuit is a third resistor R3, a fourth resistor R4, and a second diode D2 connected in series, then connected in parallel with the first resistor R1, and then connected in series with the second resistor R2.

[0063] Then we can get the following formula:

[0064]

[0065] Among them, V this the high threshold voltage of the hysteresis comparator, r1 is the resistance value of the first resistor R1, r2 is the resistance value of the second resistor R2, r3 is the resistance value of the third resistor R3, and r4 is the resistance value of the fourth resistor R4.

[0066] V th =V x3 +V f1 ; (2)

[0067] Among them, V f1 is the voltage drop of the second diode D2.

[0068] By combining equations (1) and (2), we can obtain the high threshold voltage V of the hysteresis comparator: th , and the high threshold voltage V th It is related to the voltage drop of the second diode D2.

[0069] The calculation process of the low threshold voltage of the hysteresis comparator is:

[0070] Figure 7 For an equivalent circuit to calculate the low threshold voltage, refer to Figure 7 On the basis of the above embodiments, the equivalent circuit is that the first diode D1 is connected in series with the third resistor R3, then connected in parallel with the second resistor R2, and then connected in series with the first resistor R1.

[0071] Then we can get the following formula:

[0072]

[0073] Among them, V f2 is the voltage drop of the first diode D1, r1 is the resistance value of the first resistor R1, r2 is the resistance value of the second resistor R2, and r3 is the resistance value of the third resistor R3.

[0074] V tl =V x4 -V f2 ; (4)

[0075] Among them, V tl is the lower threshold voltage of the hysteresis comparator, V f is the voltage drop of the first diode D1.

[0076] By combining equations (3) and (4), we can obtain the low threshold voltage V of the hysteresis comparator: tl , and the hysteresis comparator low threshold voltage V tl It is related to the voltage drop of the first diode D1.

[0077] Figure 8 A schematic diagram of another hysteresis comparator provided by an embodiment of the utility model, referring to Figure 8On the basis of the above embodiments, the hysteresis comparator further includes: a filter module 50; a first end of the filter module 50 is connected to the output end of the operational amplifier U1, a second end of the filter module 50 is grounded, and a third end of the filter module 50 is used to output a comparison result Vout.

[0078] Specifically, the filtering module 50 is used to filter the comparison result Vout outputted from the output terminal of the operational amplifier U1 to improve the stability of the output signal.

[0079] Optionally, continue to refer to Figure 8 The filtering module 50 includes a fifth resistor R5 and a first capacitor C1; the first end of the fifth resistor R5 is connected to the output end of the operational amplifier U1, the second end of the fifth resistor R5 is connected to the first end of the first capacitor C1, and the second end of the first capacitor C1 is grounded; wherein, the first end of the fifth resistor R5 serves as the first end of the filtering module 50, the second end of the first capacitor C1 serves as the second end of the filtering module 50, and the connection end of the second end of the fifth resistor R5 and the first end of the first capacitor C1 serves as the third end of the filtering module 50.

[0080] The fifth resistor R5 is used for voltage reduction, and the first capacitor C1 is used for energy storage.

[0081] Optionally, continue to refer to Figure 8 The hysteresis comparator further includes: a protection unit 60; a first end of the protection unit 60 is connected to the inverting input terminal IN- of the operational amplifier U1, and a second end of the protection unit 60 is grounded.

[0082] The protection unit 60 is used to suppress noise and jitter, thereby protecting the performance and normal operation of the hysteresis comparator.

[0083] Optionally, continue to refer to Figure 8 The protection unit 60 includes a sixth resistor R6; a first end of the sixth resistor R6 is connected to the inverting input terminal IN- of the operational amplifier U1, and a second end of the sixth resistor R6 is grounded.

[0084] Specifically, the sixth resistor R6 is used to ensure that the output state can be changed only when the input voltage of the inverting input terminal IN- of the operational amplifier U1 reaches a high threshold voltage or a low threshold voltage, thereby suppressing output jitter caused by noise.

[0085] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be performed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0086] The above specific implementations do not constitute a limitation on the protection scope of the present utility model. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present utility model shall be included in the protection scope of the present utility model.

Claims

1. A hysteresis comparator, characterized in that: include: An operational amplifier, a voltage dividing unit, a positive feedback network, a compensation unit and at least two voltage input units; The first end of the positive feedback network is connected to the in-phase input end of the operational amplifier and to the first end of the compensation unit, the second end of the positive feedback network is connected to the output end of the operational amplifier, the second end of the compensation unit is connected to the first end of the voltage divider unit, the second end of the voltage divider unit is connected to a reference voltage, the third end of the voltage divider unit is grounded, the inverting input end of the operational amplifier is connected to the output ends of at least two voltage input units, the input ends of the at least two voltage input units are connected to an input voltage, and at least two of the voltage input units are connected in parallel; The operational amplifier is used to compare the voltage of the in-phase input terminal and the voltage of the inverting input terminal, and output the comparison result; the voltage divider unit is used to provide the voltage of the in-phase input terminal of the operational amplifier; and the compensation unit is used to compensate the voltage of the in-phase input terminal.

2. The hysteresis comparator according to claim 1, characterized in that: The voltage dividing unit includes a first resistor and a second resistor; The first end of the first resistor is connected to the reference voltage, the second end of the first resistor is connected to the second end of the compensation unit and to the first end of the second resistor, and the second end of the second resistor is grounded.

3. The hysteresis comparator according to claim 1, characterized in that: The positive feedback network includes a third resistor; A first end of the third resistor is connected to the non-inverting input terminal of the operational amplifier, and a second end of the third resistor is connected to the output terminal of the operational amplifier.

4. The hysteresis comparator according to claim 1, characterized in that: The compensation unit includes a first diode and a second diode; at least two of the voltage input units each include a third diode; The first pole of the first diode is connected to the first end of the voltage divider unit, the second pole of the first diode is connected to the non-inverting input terminal of the operational amplifier and to the first pole of the second diode, and the second pole of the second diode is connected to the first end of the voltage divider unit; the first pole of the third diode is connected to the input voltage, and the second pole of the third diode is connected to the inverting input terminal of the operational amplifier.

5. The hysteresis comparator according to claim 4, characterized in that: The model of the first diode, the model of the second diode, and the model of the third diode are all the same.

6. The hysteresis comparator according to claim 1, characterized in that: Also includes: a fourth resistor; The first end of the fourth resistor is connected to the reference voltage, and the second end of the fourth resistor is connected to the output end of the operational amplifier.

7. The hysteresis comparator according to claim 1, characterized in that: Also includes: Filter module; The first end of the filter module is connected to the output end of the operational amplifier, the second end of the filter module is grounded, and the third end of the filter module is used to output the comparison result.

8. The hysteresis comparator according to claim 7, characterized in that: The filtering module includes a fifth resistor and a first capacitor; The first end of the fifth resistor is connected to the output end of the operational amplifier, the second end of the fifth resistor is connected to the first end of the first capacitor, and the second end of the first capacitor is grounded; Among them, the first end of the fifth resistor serves as the first end of the filter module, the second end of the first capacitor serves as the second end of the filter module, and the connection end of the second end of the fifth resistor and the first end of the first capacitor serves as the third end of the filter module.

9. The hysteresis comparator according to claim 1, characterized in that: Also includes: Protection unit; A first terminal of the protection unit is connected to the inverting input terminal of the operational amplifier, and a second terminal of the protection unit is grounded.

10. The hysteresis comparator according to claim 9, characterized in that: The protection unit includes a sixth resistor; A first end of the sixth resistor is connected to the inverting input end of the operational amplifier, and a second end of the sixth resistor is grounded.

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