Comparison control circuit

Abstract

The utility model relates to a comparison control circuit, which is provided with a comparator, four divider resistors and four filter capacitors, the divider resistors are respectively a first resistor, a second resistor, a third resistor and a fourth resistor, and the filter capacitors are respectively a first capacitor, a second capacitor, a third capacitor and a fourth capacitor. The first resistor has a first end connected with an external input voltage end, and the second resistor has a first end connected with a power supply end. An external input voltage reaches the negative input end of the comparator after being divided by the first resistor; if the voltage at the negative input end is smaller than the voltage (namely the voltage at the positive input end) of the power supply end VDD after being divided by the second resistor, the output end of the comparator outputs a high level; otherwise, the output end of the comparator outputs a bottom level. Therefore, by changing the resistance values of the first resistor and the second resistor, the output voltage of the comparator can be controlled, and the purpose of controlling the circuit to output the required high level or low level as required is achieved.

Description

Technical Field

[0001] The utility model relates to the field of circuit control, in particular to a comparison control circuit. Background Art

[0002] In the circuit control process, whether the target circuit can output the required high level or low level is crucial to ensure that the product using the target circuit works normally.

[0003] Therefore, how to control the target circuit to output the required high level or low level as needed becomes a technical problem that needs to be solved in the circuit design process. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a comparison control circuit capable of controlling a target circuit to output a high level or a low level as required in view of the above-mentioned prior art.

[0005] The technical solution adopted by the utility model to solve the above technical problems is: a comparison control circuit, characterized in that it includes:

[0006] A comparator having a negative input terminal, a positive input terminal, an output terminal, a first power supply terminal and a second power supply terminal, wherein the first power supply terminal is connected to the power supply terminal, and the second power supply terminal is connected to the ground terminal;

[0007] A first resistor having a first end connected to an external input voltage end, and a second end of the first resistor connected to a negative input end of the comparator;

[0008] A first capacitor, a first electrode of which is connected to the ground terminal, and a second electrode of which is connected to the second end of the first resistor;

[0009] A second resistor has a first end for outputting a voltage externally, and a second end of the second resistor is connected to a positive input end of the comparator;

[0010] A second capacitor, a first electrode of which is connected to the ground terminal, and a second electrode of which is respectively connected to the second end of the second resistor and the positive input terminal of the comparator;

[0011] A third resistor, a first end of which is connected to the ground terminal, and a second end of which is connected to the positive input terminal of the comparator;

[0012] A third capacitor, a first electrode of which is connected to the ground terminal, and a second electrode of which is connected to the first power supply terminal of the comparator;

[0013] a fourth resistor having a first end connected to the power supply end, and a second end of the fourth resistor connected to the output end of the comparator;

[0014] A fourth capacitor has a first electrode connected to the ground terminal, and a second electrode connected to the output terminal of the comparator.

[0015] Preferably, in the comparator circuit, the comparator model is TLC39IPWR.

[0016] Further, in the comparator circuit, the resistance of the first resistor is 4.99KΩ, and the capacitance of the first capacitor is 1nF.

[0017] As a further improvement, in the comparator circuit, the resistance of the second resistor is 698KΩ, and the capacitance of the second capacitor is 1nF.

[0018] Further, in the comparator circuit, the resistance of the third resistor is 4.64KΩ, and the capacitance of the third capacitor is 0.1μF.

[0019] Furthermore, in the comparator circuit, the resistance of the fourth resistor is 10KΩ, and the capacitance of the fourth capacitor is 1nF.

[0020] Compared with the prior art, the advantages of the utility model are: in the comparator circuit of the utility model, by setting a comparator, four voltage-dividing resistors and four filter capacitors, the voltage-dividing resistors are respectively the first resistor, the second resistor, the third resistor and the fourth resistor, the filter capacitors are respectively the first capacitor, the second capacitor, the third capacitor and the fourth capacitor, the first resistor has a first end connected to the external input voltage end, and the second resistor has a first end connected to the power supply end. After the external input voltage is divided by the first resistor, it reaches the negative input end of the comparator; if the voltage at the negative input end is less than the voltage of the power supply end VDD after the voltage is divided by the second resistor (i.e., the voltage at the positive input end), the comparator output end outputs a high level; otherwise, the comparator output end outputs a low level. Therefore, by changing the resistance values ​​of the first resistor and the second resistor, the output voltage of the comparator can be controlled, thereby achieving the purpose of controlling the circuit to output the required high level or low level as needed. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 Schematic diagram of a comparison control circuit in an embodiment of the present utility model. DETAILED DESCRIPTION

[0022] The present invention will be described in further detail below in conjunction with the accompanying drawings.

[0023] This embodiment provides a comparison control circuit. Specifically, see Figure 1As shown, the comparison control circuit of this embodiment includes a comparator U24A, four voltage-dividing resistors and four filter capacitors. The comparator U24A has a negative input terminal 1, a positive input terminal 2, an output terminal 3, a first power supply terminal 4 and a second power supply terminal 5. The four voltage-dividing resistors are a first resistor R49, a second resistor R52, a third resistor R51 and a fourth resistor R45. The four filter capacitors are a first capacitor C31, a second capacitor C32, a third capacitor C61 and a fourth capacitor C35. The first power supply terminal 4 is connected to the power supply terminal VDD, and the second power supply terminal 5 is connected to the ground terminal GND. Wherein:

[0024] The first resistor R49 has a first end connected to the external input voltage terminal IS, and a second end of the first resistor R49 is connected to the negative input terminal 1 of the comparator U24A;

[0025] A first electrode of the first capacitor C31 is connected to the ground terminal GND, and a second electrode of the first capacitor C31 is connected to the second end of the first resistor R49;

[0026] The second resistor R52 has a first end connected to the power supply terminal VDD, and a second end of the second resistor R52 is connected to the positive input terminal 2 of the comparator U24;

[0027] A first electrode of the second capacitor C32 is connected to the ground terminal GND, and a second electrode of the second capacitor C32 is respectively connected to the second end of the second resistor R52 and the positive input terminal 2 of the comparator U24A;

[0028] A first end of the third resistor R51 is connected to the ground terminal GND, and a second end of the third resistor R51 is connected to the positive input terminal 2 of the comparator U24A;

[0029] A first electrode of the third capacitor C61 is connected to the ground terminal GND, and a second electrode of the third capacitor C61 is connected to the first power supply terminal 8 of the comparator U24; wherein the second power supply terminal 4 of the comparator U24A is connected to the ground terminal GND;

[0030] The fourth resistor R45 has a first end connected to the power supply terminal VDD, and a second end of the fourth resistor R45 is connected to the output terminal 3 of the comparator U24A;

[0031] A first electrode of the fourth capacitor C35 is connected to the ground terminal GND, and a second electrode of the fourth capacitor C35 is connected to the output terminal 3 of the comparator U24.

[0032] In this embodiment, the output terminal 3 of the comparator U24A is connected to the output terminal GP3 of the entire comparison control circuit.

[0033] Specifically in this embodiment, the model of the comparator U24A is TLC39IPWR, the resistance of the first resistor R49 is 4.99KΩ, the resistance of the second resistor R52 is 698KΩ, the resistance of the third resistor R51 is 4.64KΩ, and the resistance of the fourth resistor R45 is 10KΩ; the capacitance of the first capacitor C31 is 1nF, the capacitance of the second capacitor C32 is 1nF, the capacitance of the third capacitor C61 is 0.1μF, and the capacitance of the fourth capacitor C35 is 1nF.

[0034] The following combination Figure 1 , the principle of the comparison control circuit in this embodiment is explained:

[0035] The voltage inputted from the external input voltage terminal IS is divided by the first resistor R49 and reaches the negative input terminal 2 of the comparator U24; if the voltage at the negative input terminal 1 is less than the voltage of the power supply terminal VDD divided by the second resistor R52 (i.e., the voltage at the positive input terminal 2), the output terminal 3 of the comparator U24A outputs a high level; otherwise, that is, the voltage at the negative input terminal 1 is greater than the voltage of the power supply terminal VDD divided by the second resistor R52 (i.e., the voltage at the positive input terminal 2), the output terminal 3 of the comparator U24A outputs a low level. Therefore, by changing the resistance values ​​of the first resistor R49 and the second resistor R52, the output voltage of the comparator U24A can be controlled, so as to achieve the purpose of controlling the output of the circuit to a desired high level or low level as required.

[0036] Although the preferred embodiments of the present invention are described in detail above, it should be clearly understood that the present invention may be modified and varied by those skilled in the art. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A comparison control circuit, characterized in that: include: A comparator (U24A) having a negative input terminal (1), a positive input terminal (2), an output terminal (3), a first power supply terminal (4) and a second power supply terminal (5), wherein the first power supply terminal (4) is connected to a power supply terminal (VDD), and the second power supply terminal (5) is connected to a ground terminal (GND); A first resistor (R49) having a first end connected to an external input voltage terminal (IS), and a second end of the first resistor (R49) connected to a negative input terminal (1) of a comparator (U24A); A first capacitor (C31), a first electrode of which is connected to a ground terminal (GND), and a second electrode of which is connected to a second end of a first resistor (R49); A second resistor (R52) having a first end connected to a power supply terminal (VDD), and a second end of the second resistor (R52) connected to a positive input terminal (2) of the comparator; A second capacitor (C32), a first electrode of which is connected to the ground terminal (GND), and a second electrode of which is respectively connected to the second end of the second resistor (R52) and the positive input terminal (2) of the comparator (U24A); A third resistor (R51), a first end of which is connected to the ground terminal (GND), and a second end of which is connected to the positive input terminal (2) of the comparator (U24A); A third capacitor (C61), a first electrode of which is connected to a ground terminal (GND), and a second electrode of which is connected to a first power supply terminal (4) of a comparator (U24A); A fourth resistor (R45) having a first end connected to the power supply terminal (VDD), and a second end of the fourth resistor (R45) connected to the output terminal (3) of the comparator (U24A); A fourth capacitor (C35) has a first electrode connected to the ground terminal (GND), and a second electrode connected to the output terminal (3) of the comparator (U24A).

2. The comparison control circuit according to claim 1, characterized in that: The model of the comparator (U24A) is TLC39IPWR.

3. The comparison control circuit according to claim 2, characterized in that: The resistance of the first resistor (R49) is 4.99KΩ, and the capacitance of the first capacitor (C31) is 1nF.

4. The comparison control circuit according to claim 3, characterized in that: The resistance of the second resistor (R52) is 698KΩ, and the capacitance of the second capacitor (C32) is 1nF.

5. The comparison control circuit according to claim 4, characterized in that: The resistance of the third resistor (R51) is 4.64KΩ, and the capacitance of the third capacitor (C61) is 0.1μF.

6. The comparison control circuit according to claim 5, characterized in that: The resistance of the fourth resistor (R45) is 10KΩ, and the capacitance of the fourth capacitor (C35) is 1nF.

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