CN220754798U - Filter circuit for correcting alternating current output voltage waveform - Google Patents
Filter circuit for correcting alternating current output voltage waveform Download PDFInfo
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- CN220754798U CN220754798U CN202322473317.4U CN202322473317U CN220754798U CN 220754798 U CN220754798 U CN 220754798U CN 202322473317 U CN202322473317 U CN 202322473317U CN 220754798 U CN220754798 U CN 220754798U
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Abstract
The utility model provides a filter circuit for correcting alternating current output voltage waveform, comprising: the feedback network receives the reference signal and the alternating current output voltage output by the control chip and outputs a feedback signal to the control chip, and when the control chip receives the feedback signal, the control chip outputs a digital signal; the filter comprises a first filter resistor, a second filter resistor, a grounding capacitor, a filter capacitor, a digital potentiometer and an operational amplifier, wherein at least one of the first filter resistor and the second filter resistor is a variable resistor, when the digital potentiometer receives a digital signal, the resistance value of the variable resistor is adjusted, the first filter resistor and the second filter resistor are connected in series between a first signal output end and the grounding capacitor, and the grounding capacitor is connected with a non-inverting input end of the operational amplifier. The utility model can improve the waveform quality of the alternating current output voltage.
Description
Technical Field
The utility model relates to the technical field of waveform distortion correction, in particular to a filter circuit for correcting an alternating-current output voltage waveform.
Background
The alternating current output voltage output by the measuring instrument is generally controlled by a reference signal of the MCU control chip, and in the transmission process of the reference signal, an interference noise signal is inevitably superposed, so that the reference signal is distorted, the waveform quality of the alternating current output voltage is further affected, and the waveform of the alternating current output voltage is distorted.
The traditional processing thought is to use an algorithm for compensation, but when the voltage waveform distortion exceeds a certain degree, a mode of simply relying on the algorithm for compensation is not helpful. Still other ideas are to design a filter for noise in a certain frequency band in a circuit, and when the noise frequency band is not in the related filtering frequency band or when the peripheral resistance-capacitance parameters of the filter are not completely consistent due to the production process problem, the filtering effect is greatly reduced, so that the expected filtering effect cannot be realized, and the waveform quality of the alternating-current output voltage is still affected.
Disclosure of Invention
The utility model provides a filter circuit for correcting an alternating-current output voltage waveform, which can filter an interference noise signal superposed on a reference signal, eliminate distortion of the reference signal waveform in the transmission process, correct the alternating-current output voltage waveform and improve the quality of the alternating-current output voltage waveform.
In order to achieve the technical effects, the filter circuit for correcting the alternating-current output voltage waveform is realized by adopting the following technical scheme:
the present application relates to a filter circuit for correcting an ac output voltage waveform, comprising:
the feedback network is used for receiving the reference signal and the alternating current output voltage output by the control chip and outputting a feedback signal to the control chip, and when the control chip receives the feedback signal, the control chip outputs a digital signal;
the filter comprises a first filter resistor, a second filter resistor, a grounding capacitor, a filter capacitor, a digital potentiometer and an operational amplifier, wherein at least one of the first filter resistor and the second filter resistor is a variable resistor, when the digital potentiometer receives the digital signal, the resistance value of the variable resistor is adjusted, the first filter resistor and the second filter resistor are connected in series between the first signal output end and the grounding capacitor, the grounding capacitor is connected with the non-inverting input end of the operational amplifier, the inverting input end of the operational amplifier is connected with the output end of the operational amplifier, and the output end of the operational amplifier is connected at the connection position between the first filter resistor and the second filter resistor through the filter capacitor;
when the filter is one, the output end of the operational amplifier outputs a filtered reference signal for controlling output of alternating current output voltage;
when the number of the filters is multiple, the filters are connected in series, and the filters after the series connection output the filtered reference signals and are used for controlling and outputting alternating current output voltages.
In some embodiments of the present application, one of the first filter resistor and the second filter circuit is a variable resistor, and the other is a first fixed resistance resistor, the variable resistor being a series connection of an adjustable resistor, and a second fixed resistance resistor, or a parallel connection of an adjustable resistor and a second fixed resistance resistor;
the adjustable resistor is a variable resistor in the digital potentiometer.
In some embodiments of the present application, the first filter resistor and the second filter circuit are both variable resistors;
the first filter resistor is a first adjustable resistor, a series connection of the first adjustable resistor and a first fixed resistance resistor, or a parallel connection of the first adjustable resistor and the first fixed resistance resistor;
the second filter resistor is a second adjustable resistor, a series connection of the second adjustable resistor and a second fixed resistance resistor, or a parallel connection of the second adjustable resistor and the second fixed resistance resistor;
the first adjustable resistor and the second adjustable resistor are variable resistors in the digital potentiometer.
In some embodiments of the present application, the first filter resistor and the second filter circuit are both variable resistors;
the first filter resistor is formed by connecting a first adjustable resistor and a first fixed resistance resistor in parallel;
the second filter resistor is formed by connecting a second adjustable resistor and a second fixed resistance resistor in parallel;
the first fixed resistance resistor and the second fixed resistance resistor are connected in series between the first signal output end and the grounding capacitance.
In some embodiments of the present application, the number of filters is two and includes a first filter and a second filter;
and the digital potentiometer in the first filter and the potentiometer of the second filter respectively receive the digital signals output by the control chip.
In some embodiments of the present application, the operational amplifier and the digital potentiometer in the first filter and the operational amplifier and the digital potentiometer in the second filter are integrated circuits.
Compared with the prior art, the filter circuit for correcting the alternating-current output voltage waveform has the following advantages and positive effects:
(1) The filter is arranged for correcting distortion of the reference signal caused by superposition of the interference noise signal, so that the waveform quality of the alternating-current output voltage is improved;
(2) The filter circuit is realized by adopting a pure electric circuit, and has simple structure and low input cost;
(3) The feedback network is adopted to feed back the alternating current output voltage waveform, so that the alternating current output voltage waveform can be consistent with the change of the reference voltage waveform, and the signal transmission reliability is improved.
Other features and advantages of the present utility model will become apparent upon review of the detailed description of the utility model in conjunction with the drawings.
Drawings
FIG. 1 is a block diagram showing a first embodiment of a filter circuit for correcting an AC output voltage waveform;
FIG. 2 is a circuit diagram of a filter circuit for correcting an AC output voltage waveform according to an embodiment of the present utility model;
FIG. 3 is a block diagram of a second embodiment of a filter circuit for correcting an AC output voltage waveform;
FIG. 4 is a second circuit diagram of a filter circuit for correcting an AC output voltage waveform according to an embodiment of the present utility model;
FIG. 5 is a block diagram showing a filter circuit for correcting an AC output voltage waveform according to another embodiment of the present utility model;
fig. 6 is a circuit diagram of a filter circuit for correcting an ac output voltage waveform according to another embodiment of the present utility model.
Reference numerals:
100. a first filter; 10. a digital potentiometer; 11. a first adjustable resistor; 20. a first fixed resistance resistor; 30. a second filter resistor; 31. a second adjustable resistor; 32. a second fixed resistance resistor; 40. an operational amplifier;
200. a feedback network;
300. and a second filter.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present utility model more apparent, the technical solutions of the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model, and it is apparent that the described embodiments are some embodiments of the present utility model, but not all embodiments of the present utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.
It should be noted that, in the description of the present utility model, terms such as "upper," "lower," "left," "right," "inner," "outer," and the like indicate directions or positional relationships based on the directions or positional relationships shown in the drawings, which are merely for convenience of description, and do not indicate or imply that the apparatus or elements must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
The waveform of the ac voltage reference signal Vref generated at the control chip may superimpose an interference noise signal during transmission through the circuit, affecting the waveform quality of the ac output voltage Vac.
Accordingly, in order to improve the waveform quality of the ac output voltage Vac, the present application provides a filter circuit for waveform correction of the ac output voltage, the filter circuit including a feedback network 200 and at least one filter.
Referring to fig. 1 to 6, the control chip has a first signal output terminal outputting an ac voltage reference signal Vref and a second signal output terminal.
The feedback network 200 is used for making the waveform of the ac output voltage consistent with the waveform variation of the reference signal, and receives the waveform of the ac output voltage after the waveform conversion and compares the waveform with the reference signal, and outputs feedback signals with different amplitude voltages.
After the feedback signal is input to the control chip, the control chip outputs a digital signal at the second signal output end.
The digital signal is transmitted to a filter for adjusting the cut-off frequency and the quality factor of the filter, thereby adjusting the superimposed harmonic components in the disturbed waveform, eliminating waveform distortion of the reference signal caused by superimposing the interference noise signal in the transmission process, and adjusting the waveform quality of the alternating-current output voltage.
The feedback network 200 is a common feedback circuit, and receives a signal from an input terminal, and outputs the signal after the feedback loop is acted on, where the feedback network 200 is generally constructed by resistors, capacitors, inductors, transistors, operational amplifiers, and the like.
In some embodiments of the present application, the voltage sampling circuit may be formed by a resistor and an operational amplifier, and the voltage sampling circuit samples the ac output voltage waveform through the resistor and then inputs the sampled ac output voltage waveform to a non-inverting input terminal of the operational amplifier, and an inverting input terminal of the operational amplifier is connected with a reference voltage and outputs the sampled ac output voltage waveform as a feedback signal.
In some embodiments of the present application, at least one filter is provided in order to meet the filtering requirements of the ac voltage reference signal.
As follows, description will be made on the basis of providing one filter and two filters, respectively.
Referring to fig. 1 to 4, when one filter is provided, it is denoted as a first filter 100.
The first filter 100 includes a first filter resistor, a second filter resistor 30, a ground capacitor C1, a filter capacitor C2, a digital potentiometer 10, and an operational amplifier 40.
At least one of the first filter resistor and the second filter resistor 30 is a variable resistor.
When the digital potentiometer 10 receives the digital signal output by the control chip, the resistance value of the variable resistor can be adjusted.
The first filter resistor and the second filter resistor 30 are connected in series between the first signal output terminal and the grounded capacitance C1 (i.e., the non-grounded terminal of the grounded capacitance), and the non-grounded terminal of the grounded capacitance C1 is also connected to the non-inverting input terminal of the operational amplifier 40.
The inverting input terminal of the operational amplifier 40 is connected to the output terminal thereof, and the output terminal of the operational amplifier 40 is connected at a connection position (i.e., at point a) between the first filter resistor and the second filter resistor 30 through the filter capacitor C2.
By adjusting the resistance value of the variable resistor, the cutoff frequency and the quality factor of the first filter 100 can be adjusted in combination with the capacitance value of the ground capacitor C1 and the capacitance value of the filter capacitor C2.
In some embodiments of the present application, one of the first filter resistor and the second filter resistor 30 is a variable resistor, and the other is a fixed resistance resistor.
The first filter resistor is a variable resistor, and the second filter resistor 30 is a fixed-resistance resistor.
The variable resistor may be an adjustable resistor, a resistor formed by connecting both an adjustable resistor and a fixed resistance resistor in parallel, or a resistor formed by connecting both an adjustable resistor and a fixed resistance resistor in series.
The adjustable resistor is a variable resistor of the digital potentiometer 10, and thus, the control chip controls the digital potentiometer 10 to adjust the resistance value of the variable resistor, thereby adjusting the cut-off frequency and the quality factor of the first filter 100 and improving the waveform quality of the ac output voltage.
In some embodiments of the present application, referring to fig. 1, the first filter resistor may be a resistor formed by connecting the first adjustable resistor 11 and the first fixed-resistance resistor 20 in parallel.
The second filter resistor 300 is a fixed resistance resistor.
Wherein the first adjustable resistor 11 is a variable resistor in the digital potentiometer 10.
Referring to fig. 2, the first filter resistor may be a resistor formed by connecting an adjustable resistor VR1 and a fixed-value resistor R1 in parallel.
The second filter resistor 30 may be a fixed-value resistor R2.
The adjustable resistor VR1 is a variable resistor in the digital potentiometer IC 1.
The reference signal is input to the input end of the first filter 100, the input end of the first filter 100 is transmitted to the point a through a resistor R1 and then is transmitted to the non-inverting input end of the operational amplifier 40 through a resistor R2, an adjustable resistor VR1 in the digital potentiometer IC1 is connected to two ends of the resistor R1 in parallel, one end of a grounding capacitor C1 is connected with the non-inverting input end of the operational amplifier A1, the other end of the grounding capacitor C1 is connected with a GND network, and the inverting input end of the operational amplifier A1 is connected with the output end of the operational amplifier A1.
The filter capacitor C2 is connected in parallel between the output terminal of the operational amplifier A1 and the point a. The output terminal of the operational amplifier A1 outputs the filtered reference signal.
When the feedback network 200 outputs a feedback signal, the control chip outputs a digital signal to the digital potentiometer 10, the digital potentiometer 10 has a digital interface, the digital interface receives the digital signal, and the control chip controls the resistance value of the adjustable resistor VR1 in the digital potentiometer 10 by writing data into a register in the digital potentiometer 10 due to the self-contained register of the digital potentiometer 10, so as to achieve the purpose of adjusting the cutoff frequency and the quality factor of the first filter 100.
In some embodiments of the present application, each of the first and second filter resistors 30 is a variable resistor.
The first filter resistor may be an adjustable resistor, a resistor formed by connecting the adjustable resistor and a fixed resistance resistor in parallel, or a resistor formed by connecting the adjustable resistor and the fixed resistance resistor in series.
The second filter resistor 30 may be an adjustable resistor, a resistor formed by connecting both an adjustable resistor and a fixed resistance resistor in parallel, or a resistor formed by connecting both an adjustable resistor and a fixed resistance resistor in series.
Referring to fig. 3, the first filter resistor may be a resistor formed by connecting the first adjustable resistor 11 and the first fixed resistor 20 in parallel; the second filter resistor 30 may be a resistor formed by connecting the second adjustable resistor 31 and the second fixed resistor 32 in parallel.
The first adjustable resistor 11 and the second adjustable resistor 31 described above are the first variable resistor and the second variable resistor in the digital potentiometer 10, respectively.
The number of variable resistors in the digital potentiometer 10 can be selected according to the needs of the user.
Referring to fig. 4, the first filter resistor may be a resistor formed by connecting an adjustable resistor VR1 and a fixed resistance resistor R1 in parallel.
The second filter resistor 30 may be a resistor formed by connecting an adjustable resistor VR2 and a fixed-value resistor R2 in parallel.
The adjustable resistor VR1 and the adjustable resistor VR2 are variable resistors in the digital potentiometer IC 1.
The reference signal is input to the input end of the first filter 100, the input end of the first filter 100 is transmitted to the point a through a resistor R1 and then is transmitted to the non-inverting input end of an operational amplifier A1 through a resistor R2, an adjustable resistor VR1 in a digital potentiometer IC1 is connected to two ends of the resistor R1 in parallel, an adjustable resistor VR2 in the digital potentiometer IC1 is connected to two ends of the resistor R2 in parallel, one end of a grounding capacitor C1 is connected with the non-inverting input end of the operational amplifier A1, the other end of the grounding capacitor C1 is connected with a GND network, and the inverting input end of the operational amplifier A1 is connected with the output end of the operational amplifier A1.
The filter capacitor C2 is connected in parallel between the output terminal of the operational amplifier A1 and the point a. The output terminal of the operational amplifier A1 outputs the filtered reference signal.
When the feedback network 200 outputs a feedback signal, the control chip outputs a digital signal to the digital potentiometer 10, the digital potentiometer 10 is provided with a register, and the control chip controls the resistance of the adjustable resistor VR1 and the resistance of the adjustable resistor VR2 in the digital potentiometer 10 by writing data into the register in the digital potentiometer 10, so as to achieve the purpose of adjusting the cut-off frequency and the quality factor of the first filter 100.
When the reference signal filtered by the first filter 100 is applied to a circuit to output an ac output voltage, the waveform distortion of the reference signal is eliminated, and the waveform of the ac output voltage is kept consistent with the waveform variation of the reference signal, so that the reliability and accuracy of signal transmission are realized.
The circuit described above may be a circuit in a circuit system to which an ac signal needs to be applied, and is not limited herein.
The circuit may be a measurement circuit of a measuring instrument.
Referring to fig. 4, when two filters are provided, the two filters are connected in series to form a multi-order filtering function.
The two filters include a first filter 100 and a second filter 300, and the structure of the second filter 300 may be the structure of the first filter 100 as described above.
The first filter 100 includes a first filter resistor, a second filter resistor 30, a ground capacitor C1, a filter capacitor C2, a digital potentiometer 10, and an operational amplifier 40.
At least one of the first filter resistor and the second filter resistor 30 in the first filter 100 is a variable resistor.
The second filter 300 also includes a first filter resistor, a second filter resistor, a ground capacitor, a filter capacitor, a digital potentiometer, and an operational amplifier.
Wherein at least one of the first filter resistor and the second filter resistor in the second filter 300 is a variable resistor.
Therefore, when the digital potentiometer 10 of the first filter 100 and the digital potentiometer of the second filter 300 receive the digital signal, the cut-off frequency and the quality factor of the first filter 100 are adjusted and the cut-off frequency and the quality factor of the second filter 300 are adjusted at the same time, so that the cut-off frequency and the quality factor of the multi-order filter formed by the first filter 100 and the second filter 300 connected in series are adjusted.
Referring to fig. 5, the first filter resistor may be a resistor formed by connecting the first adjustable resistor 11 and the first fixed-value resistor 20 in parallel.
The second filter resistor 30 may be a resistor formed by connecting the second adjustable resistor 31 and the second fixed resistor 32 in parallel.
Wherein the first adjustable resistor 11 and the second adjustable resistor 31 are respectively a first variable resistor and a second variable resistor in the digital potentiometer 10.
Referring to fig. 6, the first filter resistor in the first filter 100 may be a resistor formed by connecting an adjustable resistor VR1 and a fixed resistor R1 in parallel.
The second filter resistor 30 in the first filter 100 may be a resistor formed by connecting an adjustable resistor VR2 and a fixed resistor R2 in parallel.
The adjustable resistor VR1 and the adjustable resistor VR2 are a first variable resistor and a second variable resistor in the digital potentiometer IC1, respectively.
The first filter resistor in the second filter 300 may be a resistor formed by connecting an adjustable resistor VR3 and a fixed resistor R3 in parallel.
The second filter resistor in the second filter 300 may be a resistor formed by connecting an adjustable resistor VR4 and a fixed resistor R4 in parallel.
The adjustable resistor VR3 and the adjustable resistor VR4 are a first variable resistor and a second variable resistor in the digital potentiometer IC2, respectively.
The reference signal is input to the input end of the first filter 100, the input end of the first filter 100 is transmitted to the point a through a resistor R1 and then is transmitted to the non-inverting input end of an operational amplifier A1 through a resistor R2, an adjustable resistor VR1 in a digital potentiometer IC1 is connected to two ends of the resistor R1 in parallel, an adjustable resistor VR2 in the digital potentiometer IC1 is connected to two ends of the resistor R2 in parallel, one end of a grounding capacitor C1 is connected with the non-inverting input end of the operational amplifier A1, the other end of the grounding capacitor C1 is connected with a GND network, and the inverting input end of the operational amplifier A1 is connected with the output end of the operational amplifier A1.
The filter capacitor C2 is connected in parallel between the output terminal of the operational amplifier A1 and the point a. The output of the operational amplifier A1 is connected to the input of the second filter 300.
The input end of the second filter 300 is connected with a resistor R3, the resistor R3 is connected with a resistor R4 through a point b, the other end of the resistor R4 is connected with the non-inverting input end of an operational amplifier A2, a variable resistor VR3 in a digital potentiometer IC2 is connected with two ends of the resistor R3 in parallel, a variable resistor VR4 in the digital potentiometer IC2 is connected with two ends of the resistor R4 in parallel, one end of a grounding capacitor C3 is connected with the non-inverting input end of the operational amplifier A2, the other end of the grounding capacitor C3 is connected with a GND network, and the inverting input end of the operational amplifier A2 is connected with the output end of the operational amplifier A2; the filter capacitor C4 is connected in parallel between the output terminal of the operational amplifier A2 and the point b.
The output terminal of the operational amplifier A2 outputs the filtered reference signal.
When the feedback network 200 outputs the feedback signal, the control chip outputs the digital signal to the digital potentiometers IC1 and IC2, and the digital potentiometers IC1 and IC2 are self-contained with registers.
The control chip controls the resistance of the adjustable resistor VR1 and the resistance of the adjustable resistor VR2 in the digital potentiometer IC1 by writing data into a register in the digital potentiometer IC1, and controls the resistance of the adjustable resistor VR3 and the resistance of the adjustable resistor VR4 in the digital potentiometer IC2 by writing data into a register in the digital potentiometer IC2, so that the purpose of adjusting the cutoff frequency and the quality factor of the multi-order filter formed by connecting the first filter 100 and the second filter 300 in series is achieved.
When the reference signals filtered by the first filter 100 and the second filter 300 are applied to a circuit to output alternating-current output voltages, waveform distortion of the reference signals is eliminated, and meanwhile, waveform changes of the alternating-current output voltages and the reference signals can be kept consistent, so that signal transmission reliability and accuracy are realized.
The operational amplifier A1 and the digital potentiometer IC1 in the first filter 100 and the operational amplifier A2 and the digital potentiometer IC2 in the second filter 300 are integrated circuits, which are convenient for circuit design.
The number of at least one filter may also be set to more than the number described above, without limitation.
The above embodiments are only for illustrating the technical solution of the present utility model, and are not limiting; although the utility model has been described in detail with reference to the foregoing embodiments, it will be apparent to one skilled in the art that modifications may be made to the technical solutions described in the foregoing embodiments, or equivalents may be substituted for some of the technical features thereof; such modifications and substitutions do not depart from the spirit and scope of the corresponding technical solutions.
Claims (6)
1. A filter circuit for correcting an ac output voltage waveform, comprising:
the feedback network is used for receiving the reference signal and the alternating current output voltage output by the control chip and outputting a feedback signal to the control chip, and when the control chip receives the feedback signal, the control chip outputs a digital signal;
the filter comprises a first filter resistor, a second filter resistor, a grounding capacitor, a filter capacitor, a digital potentiometer and an operational amplifier, wherein at least one of the first filter resistor and the second filter resistor is a variable resistor, when the digital potentiometer receives the digital signal, the resistance value of the variable resistor is adjusted, the first filter resistor and the second filter resistor are connected in series between the signal output end of the control chip for outputting a reference signal and the grounding capacitor, the grounding capacitor is connected with the non-inverting input end of the operational amplifier, the inverting input end of the operational amplifier is connected with the output end of the operational amplifier, and the output end of the operational amplifier is connected at the connection position between the first filter resistor and the second filter resistor through the filter capacitor;
when the filter is one, the output end of the operational amplifier outputs a filtered reference signal for controlling output of alternating current output voltage;
when the number of the filters is multiple, the filters are connected in series, and the filters after the series connection output the filtered reference signals and are used for controlling and outputting alternating current output voltages.
2. The filter circuit for correcting an AC output voltage waveform according to claim 1, wherein,
one of the first filter resistor and the second filter circuit is a variable resistor, and the other is a first fixed resistance resistor;
the variable resistor is a series connection of an adjustable resistor, an adjustable resistor and a second fixed resistance resistor, or a parallel connection of the adjustable resistor and the second fixed resistance resistor;
the adjustable resistor is a variable resistor in the digital potentiometer.
3. The filter circuit for correcting an AC output voltage waveform according to claim 1, wherein,
the first filter resistor and the second filter circuit are variable resistors;
the first filter resistor is a first adjustable resistor, a series connection of the first adjustable resistor and a first fixed resistance resistor, or a parallel connection of the first adjustable resistor and the first fixed resistance resistor;
the second filter resistor is a second adjustable resistor, a series connection of the second adjustable resistor and a second fixed resistance resistor, or a parallel connection of the second adjustable resistor and the second fixed resistance resistor;
the first adjustable resistor and the second adjustable resistor are variable resistors in the digital potentiometer.
4. The filter circuit for correcting an AC output voltage waveform according to claim 3, wherein,
the first filter resistor and the second filter circuit are variable resistors;
the first filter resistor is formed by connecting a first adjustable resistor and a first fixed resistance resistor in parallel;
the second filter resistor is formed by connecting a second adjustable resistor and a second fixed resistance resistor in parallel;
the first fixed resistance resistor and the second fixed resistance resistor are connected in series between the signal output end and the grounding capacitance.
5. The filter circuit for correcting an AC output voltage waveform according to claim 1, wherein,
the number of the filters is two, and the filter comprises a first filter and a second filter;
and the digital potentiometer in the first filter and the potentiometer of the second filter respectively receive the digital signals output by the control chip.
6. The filter circuit for correcting an AC output voltage waveform according to claim 5, wherein,
the operational amplifier and the digital potentiometer in the first filter and the operational amplifier and the digital potentiometer in the second filter are integrated circuits.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202322473317.4U CN220754798U (en) | 2023-09-12 | 2023-09-12 | Filter circuit for correcting alternating current output voltage waveform |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202322473317.4U CN220754798U (en) | 2023-09-12 | 2023-09-12 | Filter circuit for correcting alternating current output voltage waveform |
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| Publication Number | Publication Date |
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| CN220754798U true CN220754798U (en) | 2024-04-09 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202322473317.4U Active CN220754798U (en) | 2023-09-12 | 2023-09-12 | Filter circuit for correcting alternating current output voltage waveform |
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| CN (1) | CN220754798U (en) |
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- 2023-09-12 CN CN202322473317.4U patent/CN220754798U/en active Active
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