Op amp based drive circuit

Abstract

The utility model discloses a driving circuit based on an operational amplifier, comprising: at least one operational amplifier, a first power amplifier module, and a second power amplifier module; the same-direction input terminal of the operational amplifier is connected in series with a resistor R10 and then grounded, and the same-direction input terminal of the operational amplifier also serves as the positive signal input terminal of the driving circuit based on the operational amplifier; the reverse input terminal of the operational amplifier is connected to its output terminal; the output terminal of the operational amplifier serves as the signal output terminal of the driving circuit based on the operational amplifier; the input terminal of the first power amplifier module is connected to a positive DC power supply, and the output terminal of the first power amplifier module is connected to the positive DC power supply input terminal of the operational amplifier; the input terminal of the second power amplifier module is connected to a negative DC power supply, and the output terminal of the second power amplifier module is connected to the negative DC power supply input terminal of the operational amplifier. The driving circuit based on the operational amplifier of the utility model has high power amplifier conversion rate, low noise, good stability, and undistorted output waveform.

Description

Technical Field

[0001] The utility model relates to the field of driving circuits, in particular to a driving circuit based on an operational amplifier. Background Art

[0002] The drive circuit is located between the main circuit and the control circuit and is an intermediate circuit used to amplify the signal of the control circuit (i.e., amplify the signal of the control circuit so that it can drive the power transistor).

[0003] The basic task of the drive circuit is to convert the signal from the information electronic circuit into a signal that is added between the control terminal and the common terminal of the power electronic device to turn it on or off according to the requirements of its control target.

[0004] The function of the drive circuit: amplify the PWM pulse output by the control circuit to a level sufficient to drive the power transistor - switching power amplification function.

[0005] The traditional driving circuit has a low power amplifier conversion rate and a distorted output waveform. For example, the driving circuit in the prior art uses an integrated amplifier IC chip TDA7293 for power amplification. Figure 1 As shown in the figure, the output waveform when the integrated amplifier IC chip TDA7293 is used for power amplification in the prior art is seriously distorted and has become a trapezoidal wave. Utility Model Content

[0006] The utility model aims to overcome the deficiencies in the prior art and provide a driving circuit based on an operational amplifier, which has high power amplifier conversion rate, low noise, good stability and undistorted output waveform.

[0007] The purpose of this utility model is achieved through the following technical solutions:

[0008] The operational amplifier-based driving circuit includes: at least one operational amplifier, a first power amplifier module, and a second power amplifier module;

[0009] The non-inverting input terminal of the operational amplifier is connected in series with a resistor R10 and then grounded, and the non-inverting input terminal of the operational amplifier also serves as the positive signal input terminal of the operational amplifier-based driving circuit; the reverse input terminal of the operational amplifier is connected to its output terminal; the output terminal of the operational amplifier serves as the signal output terminal of the operational amplifier-based driving circuit;

[0010] The input end of the first power amplifier module is connected to a positive DC power supply, and the output end of the first power amplifier module is connected to a positive DC power supply input end of the operational amplifier;

[0011] The input end of the second power amplifier module is connected to the negative DC power supply, and the output end of the second power amplifier module is connected to the negative DC power supply input end of the operational amplifier.

[0012] Preferably, the operational amplifier is TL081HIDBVR.

[0013] Preferably, the first power amplifier module includes: a first PNP transistor Q2, a first NPN transistor Q4, a first voltage regulator diode D3, a first resistor R4, a second resistor R6 and a third resistor R9;

[0014] The collector of the first PNP transistor Q2 is connected to a 0V voltage, the emitter is connected in series with the third resistor R9 and then connected to a positive DC power supply; the base is connected in series with the first resistor R4 and then connected to a positive DC power supply;

[0015] The collector of the first NPN transistor Q4 is connected to the base of the first PNP transistor Q2; the emitter of the first NPN transistor Q4 is connected to the positive DC power supply input terminal of the operational amplifier; the base of the first NPN transistor Q4 is connected in series with the second resistor R6 and then connected to the positive DC power supply; the base of the first NPN transistor Q4 is also connected in series with the first voltage regulator diode D3 and then grounded.

[0016] Preferably, the second power amplifier module includes: a second PNP transistor Q6, a second NPN transistor Q8, a second voltage regulator diode D4, a fourth resistor R13, a fifth resistor R12 and a sixth resistor R11;

[0017] The collector of the second NPN transistor Q8 is connected to a 0V voltage, the emitter is connected in series with the fourth resistor R13 and then connected to a negative DC power supply; the base is connected in series with the fifth resistor R12 and then connected to a negative DC power supply;

[0018] The collector of the second PNP transistor Q6 is connected to the base of the second NPN transistor Q8; the emitter of the second PNP transistor Q6 is connected to the negative DC power supply input terminal of the operational amplifier; the base of the second PNP transistor Q6 is connected in series with the sixth resistor R11 and then connected to the negative DC power supply; the base of the second PNP transistor Q6 is also connected in series with the second voltage regulator diode D4 and then grounded.

[0019] Preferably, the first voltage stabilizing diode D3 is MM1Z12V.

[0020] Preferably, the first PNP transistor Q2 is MJE172.

[0021] Preferably, the first NPN transistor Q4 is BC847C.

[0022] Preferably, the second voltage stabilizing diode D4 is MM1Z12V.

[0023] Preferably, the second PNP transistor Q6 is BC857C.

[0024] Preferably, the second NPN transistor Q8 is MJE182.

[0025] Compared with the prior art, the utility model has at least the following advantages:

[0026] The operational amplifier-based driving circuit of the utility model has a high power amplifier conversion rate, which is one order of magnitude (10 times) higher than that of the traditional circuit, low noise, good stability, and no distortion of the output waveform;

[0027] The drive circuit based on the operational amplifier of the utility model has low noise and high stability; the drive circuit based on the operational amplifier of the utility model uses a high-performance operational amplifier as input, and also has the characteristics of the operational amplifier, with very low noise and very high indicators; such as very low temperature drift 2uV / ℃ and low offset voltage 1mV and very low distortion;

[0028] The operational amplifier-based driving circuit of the utility model can be made into a DC power amplifier with a power bandwidth of 0-200KHz; the DC power amplifier brings a low-frequency phase difference of 0 and a very low dive;

[0029] The operational amplifier-based driving circuit of the utility model has an extremely high rate, and the mid- and high-frequency of the power amplifier has very little delay and phase difference, which can restore the sound more perfectly, showing richer overtones and more delicate treble. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model 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 paying creative work.

[0031] Figure 1 It is an output waveform diagram of the prior art;

[0032] Figure 2 The schematic diagram of the driving circuit based on the operational amplifier of the utility model;

[0033] Figure 3 This is an output waveform diagram of the operational amplifier-based driving circuit of the utility model. DETAILED DESCRIPTION

[0034] In order to facilitate the understanding of the present invention, the present invention will be described more comprehensively with reference to the accompanying drawings. The accompanying drawings show preferred embodiments of the present invention.

[0035] Example

[0036] like Figure 2 As shown, the utility model discloses a driving circuit based on an operational amplifier, including: at least one operational amplifier AR1, a first power amplifier module, and a second power amplifier module. In this embodiment, the model of the operational amplifier AR1 is TL081HIDBVR. Among them, the same-direction input terminal of the operational amplifier AR1 is connected to ground after being connected in series with a resistor R10, and the same-direction input terminal of the operational amplifier AR1 also serves as the positive signal input terminal of the driving circuit based on the operational amplifier; the reverse input terminal of the operational amplifier AR1 is connected to its output terminal; the output terminal of the operational amplifier AR1 serves as the signal output terminal of the driving circuit based on the operational amplifier. The input terminal of the first power amplifier module is connected to the positive DC power supply +VCC1, and the output terminal of the first power amplifier module is connected to the positive DC power supply input terminal of the operational amplifier. The input terminal of the second power amplifier module is connected to the negative DC power supply, and the output terminal of the second power amplifier module is connected to the negative DC power supply input terminal of the operational amplifier.

[0037] In this embodiment, after the voltage signal is input from the non-inverting input terminal of the operational amplifier AR1, the V / I conversion circuit of the operational amplifier AR1 converts the voltage signal input from the operational amplifier AR1 into a current signal and outputs it from the output terminal of the operational amplifier AR1; that is, after the voltage signal is input from the non-inverting input terminal of the operational amplifier AR1, it is converted into a current signal and output.

[0038] like Figure 2 As shown, in this embodiment, the first power amplifier module includes: a first PNP transistor Q2, a first NPN transistor Q4, a first voltage regulator diode D3, a first resistor R4, a second resistor R6 and a third resistor R9. The collector of the first PNP transistor Q2 is connected to a 0V voltage, the emitter is connected in series with the third resistor R9 and then connected to a positive DC power supply +VCC1; the base is connected in series with the first resistor R4 and then connected to a positive DC power supply +VCC1; the collector of the first NPN transistor Q4 is connected to the base of the first PNP transistor Q2; the emitter of the first NPN transistor Q4 is connected to the positive DC power input terminal of the operational amplifier; the base of the first NPN transistor Q4 is connected in series with the second resistor R6 and then connected to a positive DC power supply +VCC1; the base of the first NPN transistor Q4 is also connected in series with the first voltage regulator diode D3 and then grounded. In this embodiment, the model of the first voltage regulator diode D3 is MM1Z12V. The model of the first PNP transistor Q2 is MJE172. The model of the first NPN transistor Q4 is BC847C.

[0039] like Figure 2As shown, the first power amplifier module converts the voltage signal of the positive DC power supply +VCC1 into a current signal and performs secondary amplification through the first PNP transistor Q2 and the first NPN transistor Q4, and converts the amplified DC current signal into a voltage signal through the first voltage regulator diode D3 and inputs it to the positive DC power supply input terminal of the operational amplifier, thereby providing an operating voltage for the operational amplifier AR1.

[0040] In this embodiment, the first power amplifier module adopts two-stage amplification. Of course, in other embodiments, the first power amplifier module can also adopt one-stage amplification or multi-stage amplification.

[0041] like Figure 2 As shown, in this embodiment, the second power amplifier module includes: a second PNP transistor Q6, a second NPN transistor Q8, a second voltage regulator diode D4, a fourth resistor R13, a fifth resistor R12 and a sixth resistor R11. The collector of the second NPN transistor Q8 is connected to a 0V voltage, the emitter is connected in series with the fourth resistor R13 and then connected to a negative DC power supply -VCC1; the base is connected in series with the fifth resistor R12 and then connected to a negative DC power supply -VCC1. The collector of the second PNP transistor Q6 is connected to the base of the second NPN transistor Q8; the emitter of the second PNP transistor Q6 is connected to the negative DC power input terminal of the operational amplifier; the base of the second PNP transistor Q6 is connected in series with the sixth resistor R11 and then connected to a negative DC power supply -VCC1; the base of the second PNP transistor Q6 is also connected in series with a second voltage regulator diode D4 and then grounded. In this embodiment, the model of the second voltage regulator diode D4 is MM1Z12V. The model of the second PNP transistor Q6 is BC857C. The model of the second NPN transistor Q8 is MJE182.

[0042] like Figure 2 As shown, the second power amplifier module converts the voltage signal of the negative DC power supply -VCC1 into a current signal and performs secondary amplification through the second PNP transistor Q6 and the second NPN transistor Q8, and converts the amplified DC current signal into a voltage signal through the second voltage regulator diode D4 and inputs it to the negative DC power supply input terminal of the operational amplifier, thereby providing an operating voltage for the operational amplifier AR1.

[0043] In this embodiment, the second power amplifier module adopts two-stage amplification. Of course, in other embodiments, the second power amplifier module can also adopt one-stage amplification or multi-stage amplification.

[0044] like Figure 1 and Figure 3 As shown, the operational amplifier-based driving circuit of the utility model has a high power amplifier conversion rate, which can be an order of magnitude (10 times) higher than the power amplifier conversion rate of the traditional circuit, low noise, good stability, and no distortion of the output waveform;

[0045] The drive circuit based on the operational amplifier of the utility model has low noise and high stability; the drive circuit based on the operational amplifier of the utility model uses a high-performance operational amplifier as input, and also has the characteristics of the operational amplifier, with very low noise and very high indicators; such as very low temperature drift 2uV / ℃ and low offset voltage 1mV and very low distortion;

[0046] The operational amplifier-based driving circuit of the utility model can be made into a DC power amplifier with a power bandwidth of 0-200KHz; the DC power amplifier brings a low-frequency phase difference of 0 and a very low dive;

[0047] The operational amplifier-based driving circuit of the utility model has an extremely high rate, and the mid- and high-frequency of the power amplifier has very little delay and phase difference, which can restore the sound more perfectly, showing richer overtones and more delicate treble.

[0048] The above-mentioned embodiments only express several implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. A driving circuit based on an operational amplifier, characterized in that: include: At least one operational amplifier, a first power amplifier module, and a second power amplifier module; The non-inverting input terminal of the operational amplifier is connected in series with a resistor R10 and then grounded, and the non-inverting input terminal of the operational amplifier also serves as the positive signal input terminal of the operational amplifier-based driving circuit; the reverse input terminal of the operational amplifier is connected to its output terminal; the output terminal of the operational amplifier serves as the signal output terminal of the operational amplifier-based driving circuit; The input end of the first power amplifier module is connected to a positive DC power supply, and the output end of the first power amplifier module is connected to a positive DC power supply input end of the operational amplifier; The input end of the second power amplifier module is connected to the negative DC power supply, and the output end of the second power amplifier module is connected to the negative DC power supply input end of the operational amplifier.

2. The operational amplifier-based driving circuit according to claim 1, characterized in that: The operational amplifier is TL081HIDBVR.

3. The operational amplifier-based driving circuit according to claim 1 or 2, characterized in that: The first power amplifier module includes: a first PNP transistor Q2, a first NPN transistor Q4, a first voltage regulator diode D3, a first resistor R4, a second resistor R6 and a third resistor R9; The collector of the first PNP transistor Q2 is connected to a 0V voltage, the emitter is connected in series with the third resistor R9 and then connected to a positive DC power supply; the base is connected in series with the first resistor R4 and then connected to a positive DC power supply; The collector of the first NPN transistor Q4 is connected to the base of the first PNP transistor Q2; the emitter of the first NPN transistor Q4 is connected to the positive DC power supply input terminal of the operational amplifier; the base of the first NPN transistor Q4 is connected in series with the second resistor R6 and then connected to the positive DC power supply; the base of the first NPN transistor Q4 is also connected in series with the first voltage regulator diode D3 and then grounded.

4. The operational amplifier-based driving circuit according to claim 1 or 2, characterized in that: The second power amplifier module includes: a second PNP transistor Q6, a second NPN transistor Q8, a second voltage regulator diode D4, a fourth resistor R13, a fifth resistor R12 and a sixth resistor R11; The collector of the second NPN transistor Q8 is connected to a 0V voltage, the emitter is connected in series with the fourth resistor R13 and then connected to a negative DC power supply; the base is connected in series with the fifth resistor R12 and then connected to a negative DC power supply; The collector of the second PNP transistor Q6 is connected to the base of the second NPN transistor Q8; the emitter of the second PNP transistor Q6 is connected to the negative DC power supply input terminal of the operational amplifier; the base of the second PNP transistor Q6 is connected in series with the sixth resistor R11 and then connected to the negative DC power supply; the base of the second PNP transistor Q6 is also connected in series with the second voltage regulator diode D4 and then grounded.

5. The operational amplifier-based driving circuit according to claim 3, characterized in that: The first voltage stabilizing diode D3 is MM1Z12V.

6. The operational amplifier-based driving circuit according to claim 3, characterized in that: The first PNP transistor Q2 is MJE172.

7. The operational amplifier-based driving circuit according to claim 3, characterized in that: The first NPN transistor Q4 is BC847C.

8. The operational amplifier-based driving circuit according to claim 4, characterized in that: The second voltage stabilizing diode D4 is MM1Z12V.

9. The operational amplifier-based driving circuit according to claim 4, characterized in that: The second PNP transistor Q6 is BC857C.

10. The operational amplifier-based driving circuit according to claim 4, characterized in that: The second NPN transistor Q8 is MJE182.

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