CN210518805U - Amplifying circuit and playing device - Google Patents
Amplifying circuit and playing device Download PDFInfo
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- CN210518805U CN210518805U CN201922370332.XU CN201922370332U CN210518805U CN 210518805 U CN210518805 U CN 210518805U CN 201922370332 U CN201922370332 U CN 201922370332U CN 210518805 U CN210518805 U CN 210518805U
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- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R3/00—Circuits for transducers, loudspeakers or microphones
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Abstract
The utility model provides an amplifier circuit and playback devices, include: an N-order filter, a comparator and a digital circuit; after an original audio signal passes through the N-order filter, a filtering signal is obtained; the filtering signal passes through the comparator and the digital circuit and then outputs a corresponding digital signal; the number of the operational amplifiers adopted in the N-order filter is smaller than N, and N is a natural number larger than 1. The utility model discloses an amplifying circuit, under the prerequisite of guaranteeing the filtering effect, the quantity through the operational amplifier who uses in reducing the N rank filter reduces the shared circuit area of amplifying circuit and consumption.
Description
Technical Field
The utility model relates to an integrated circuit technical field especially relates to an acoustic amplification circuit and playback devices.
Background
The existing amplifying circuit generally adopts two-stage filtering processing, wherein a filtering device adopts an operational amplifier, then an analog signal is converted into a digital signal by a comparator after filtering, and finally an audio signal is output by a player. The more the number of the filters in the amplifying circuit is, the higher the gain is, and the stronger the anti-jamming capability of the circuit is.
However, in an integrated circuit, the operational amplifier needs to occupy a large circuit area and has relatively large power consumption.
SUMMERY OF THE UTILITY MODEL
The utility model provides an amplifying circuit and playback apparatus, under the prerequisite of guaranteeing the filtering effect, reduce shared circuit area of amplifying circuit and consumption through the quantity that reduces the operational amplifier who uses in the N rank filter.
In a first aspect, an embodiment of the present invention further provides an amplifying circuit, including: an N-order filter, a comparator and a digital circuit; after an original audio signal passes through the N-order filter, a filtering signal is obtained; the filtering signal passes through the comparator and the digital circuit and then outputs a corresponding digital signal; the number of the operational amplifiers adopted in the N-order filter is smaller than N, and N is a natural number larger than 1.
In one possible design, the nth order filter includes an i-1 th order filter and an ith order filter, where i has a value range of 2, 3, …, N;
the i-1 th order filter is a first type filter, and the first type filter comprises: the operational amplifier, the first capacitor and the second capacitor; the positive input end of the operational amplifier is connected to the positive output end of the previous-order filter, the negative input end of the operational amplifier is connected to the negative output end of the previous-order filter, the first output end of the operational amplifier forms the first output end of the filter, one end of the first capacitor is connected to the positive input end of the operational amplifier, and the other end of the first capacitor is connected to the negative output end of the operational amplifier; one end of the second capacitor is connected to the negative input end of the operational amplifier, and the other end of the second capacitor is connected to the positive output end of the operational amplifier;
the ith order filter is a second type filter, and the second type filter comprises: the first capacitor, the second resistor, the third capacitor and the fourth capacitor are connected in series;
one end of the third capacitor is connected to the positive input end of the i-1 th order filter, the other end of the third capacitor is connected to one end of the first resistor, and the other end of the first resistor is connected to the positive output end of the operational amplifier;
one end of the fourth capacitor is connected to the negative input end of the i-1 th order filter, the other end of the fourth capacitor is connected to one end of the second resistor, and the other end of the second resistor is connected to the negative output end of the operational amplifier.
In one possible design, the nth order filter includes an i-1 th order filter and an ith order filter, where i has a value range of 2, 3, …, N;
the i-1 th order filter is a first type filter, and the first type filter comprises: the operational amplifier, the first capacitor and the second capacitor; the positive input end of the operational amplifier is connected to the positive output end of the previous-order filter, the negative input end of the operational amplifier is connected to the negative output end of the previous-order filter, the first output end of the operational amplifier forms the first output end of the filter, one end of the first capacitor is connected to the positive input end of the operational amplifier, and the other end of the first capacitor is connected to the negative output end of the operational amplifier; one end of the second capacitor is connected to the negative input end of the operational amplifier, and the other end of the second capacitor is connected to the positive output end of the operational amplifier;
the ith order filter is a second type filter, and the second type filter comprises: the first capacitor, the second capacitor, the third capacitor and the fourth capacitor are connected in series;
one end of the third capacitor is connected to the positive input end of the i-1 th order filter, the other end of the third capacitor is connected to one end of the first switch capacitor, and the other end of the first switch capacitor is connected to the positive output end of the operational amplifier;
one end of the fourth capacitor is connected to the negative input end of the i-1 th order filter, the other end of the fourth capacitor is connected to one end of the second switch capacitor, and the other end of the second switch capacitor is connected to the negative output end of the operational amplifier.
In one possible design, the capacitance values of the third capacitor and the fourth capacitor in the (i-1) th order filter and the capacitance values of the first capacitor and the second capacitor in the (i-1) th order filter are the same.
In one possible design, if the i-1 st order filter is a first type filter and the i-th order filter is a first type filter, the circuit further includes: a third resistor and a fourth resistor;
the positive output end of the operational amplifier in the ith-1 st order filter is connected to the positive input end of the operational amplifier in the ith order filter through the third resistor;
and the negative output end of the operational amplifier in the ith-1 st order filter is connected to the negative input end of the operational amplifier in the ith order filter through the fourth resistor.
In one possible design, further comprising: a fifth capacitor and a sixth capacitor;
one end of the fifth capacitor is connected to the positive output end of the operational amplifier in the ith-1 st order filter, and the other end of the fifth capacitor is connected to the positive input end of the operational amplifier in the ith order filter;
one end of the sixth capacitor is connected to the negative output end of the operational amplifier in the ith-1 st order filter, and the other end of the sixth capacitor is connected to the negative input end of the operational amplifier in the ith order filter.
In one possible design, further comprising: the weighted adder divides the original audio signals into two paths, and a first path of original audio signals pass through the N-order filter to obtain filtered signals; and the second path of original audio signal is subjected to weighted addition with the filtering signal through the weighted adder to obtain a weighted addition signal, and the weighted addition signal passes through the comparator and the digital circuit to output a corresponding digital signal.
In one possible design, the weighted adder includes: a fifth resistor, a sixth resistor, a seventh resistor, and an eighth resistor;
one end of the fifth resistor is connected with the first output end of the last-order filter, and one end of the sixth resistor is connected with the positive output end of the second path of original audio signals; the other end of the fifth resistor and the other end of the sixth resistor are both connected to a first input end of an integrated circuit formed by the comparator and the digital circuit;
one end of the seventh resistor is connected with the second output end of the last-order filter, and one end of the eighth resistor is connected with the negative output end of the second path of original audio signal; the other end of the seventh resistor and the other end of the eighth resistor are both connected to a second input end of an integrated circuit formed by the comparator and the digital circuit.
In one possible design, the weighted adder includes: the third switch capacitor, the fourth switch capacitor, the fifth switch capacitor and the sixth switch capacitor;
one end of the third switched capacitor is connected with the first output end of the last-stage filter, and one end of the fourth switched capacitor is connected with the positive output end of the second path of original audio signal; the other end of the third switch capacitor and the other end of the fourth switch capacitor are both connected to a first input end of an integrated circuit formed by the comparator and the digital circuit;
one end of the fifth switch capacitor is connected with the second output end of the last-stage filter, and one end of the sixth switch capacitor is connected with the negative output end of the second path of original audio signal; the other end of the fifth switch capacitor and the other end of the sixth switch capacitor are both connected to a second input end of an integrated circuit formed by the comparator and the digital circuit.
In a second aspect, an embodiment of the present invention further provides a playback device, including the amplifying circuit according to any one of the first aspects.
The utility model provides an amplifying circuit and playing device, through passing original audio signal N rank after the wave filter, obtain the filtering signal; the filtering signal passes through the comparator and the digital circuit and then outputs a corresponding digital signal; the number of the operational amplifiers adopted in the N-order filter is smaller than N, and N is a natural number larger than 1. The utility model discloses an amplifying circuit, under the prerequisite of guaranteeing the filtering effect, the quantity through the operational amplifier who uses in reducing the N rank filter reduces the shared circuit area of amplifying circuit and consumption.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without inventive labor.
Fig. 1 is a schematic structural diagram of an amplifying circuit according to a first embodiment of the present invention;
fig. 2 is a schematic structural diagram of an amplifying circuit provided in the second embodiment of the present invention;
fig. 3 is a schematic structural diagram of an amplifying circuit provided in the third embodiment of the present invention;
fig. 4 is a schematic structural diagram of an amplifying circuit according to a fourth embodiment of the present invention.
With the foregoing drawings in mind, certain embodiments of the disclosure have been shown and described in more detail below. These drawings and written description are not intended to limit the scope of the disclosed concepts in any way, but rather to illustrate the concepts of the disclosure to those skilled in the art by reference to specific embodiments.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.
The terms "first," "second," "third," "fourth," and the like in the description and in the claims, as well as in the drawings, if any, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the invention described herein are, for example, capable of operation in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.
The technical solution of the present invention will be described in detail with specific examples. The following several specific embodiments may be combined with each other, and details of the same or similar concepts or processes may not be repeated in some embodiments.
The existing amplifying circuit generally adopts two-stage filtering processing, wherein a filtering device adopts an operational amplifier, then a signal after filtering is converted into a digital signal through a comparator and a digital circuit, and finally an audio signal is output by a player. The more the number of the filters in the amplifying circuit is, the higher the gain is, and the stronger the anti-jamming capability of the circuit is.
However, in an integrated circuit, the operational amplifier needs to occupy a large circuit area, and power consumption of the amplifier circuit is increased.
To the above problem, the utility model discloses aim at improving an amplifier circuit, under the prerequisite of guaranteeing the filtering effect, reduce shared circuit area and consumption of amplifier circuit through the quantity that reduces the operational amplifier who uses in the N rank filter.
The following describes the technical solution of the present invention and how to solve the above technical problems with specific embodiments. The following several specific embodiments may be combined with each other, and details of the same or similar concepts or processes may not be repeated in some embodiments. Embodiments of the present invention will be described below with reference to the accompanying drawings.
Example one
Fig. 1 is a schematic structural diagram of an amplifying circuit provided in the first embodiment of the present invention, as shown in fig. 1, the amplifying circuit in this embodiment may include: an N-order filter, a comparator and a digital circuit; after an original audio signal passes through an N-order filter, a filtering signal is obtained; the filtered signal passes through an integrated circuit consisting of a comparator and a digital circuit and then outputs a corresponding digital signal; the number of the operational amplifiers adopted in the N-order filter is smaller than N, and N is a natural number larger than 1.
Specifically, referring to fig. 1, the positive input terminal of the first-stage filter receives the positive signal Vip of the first audio signal, the negative input terminal of the first-stage filter receives the negative signal Vin of the first audio signal, and the reference terminal of the first-stage filter receives the reference signal Vcom. The positive output end of the first-order filter is connected to the positive input end of the second-order filter, and the negative output end of the first-order filter is connected to the negative input end of the second-order filter. The positive output end and the negative output end of the last-order filter are connected to the input end of an integrated circuit formed by the comparator and the digital circuit, and the output end of the integrated circuit formed by the comparator and the digital circuit is connected to the player.
The amplifying circuit of the embodiment reduces the circuit area and power consumption occupied by the amplifying circuit by reducing the number of operational amplifiers used in the N-order filter on the premise of ensuring the filtering effect.
Example two
Fig. 2 is a schematic structural diagram of an amplifying circuit provided by the second embodiment of the present invention, as shown in fig. 2, the amplifying circuit in this embodiment may include: the integrated circuit consists of an N-order filter, a comparator and a digital circuit; after an original audio signal passes through an N-order filter, a filtering signal is obtained; the filtered signal passes through an integrated circuit consisting of a comparator and a digital circuit and then outputs a corresponding digital signal; the number of the operational amplifiers adopted in the N-order filter is smaller than N, and N is a natural number larger than 1.
In an alternative embodiment, referring to fig. 2, the nth order filter includes an i-1 st order filter and an ith order filter, where i has a value in the range of 2, 3, …, N. The i-1 st order filter is a first type filter, and the first type filter comprises: the operational amplifier, the first capacitor and the second capacitor; the positive input end of the operational amplifier is connected to the positive output end of the previous-order filter, the negative input end of the operational amplifier is connected to the negative output end of the previous-order filter, the first output end of the operational amplifier forms the first output end of the filter, one end of the first capacitor is connected to the positive input end of the operational amplifier, and the other end of the first capacitor is connected to the negative output end of the operational amplifier; one end of the second capacitor is connected to the negative input end of the operational amplifier, and the other end of the second capacitor is connected to the positive output end of the operational amplifier. The ith order filter is a second type filter, and the second type filter comprises: the first capacitor, the second resistor, the third capacitor and the fourth capacitor are connected in series; one end of the third capacitor is connected to the positive input end of the i-1 th order filter, the other end of the third capacitor is connected to one end of the first resistor, and the other end of the first resistor is connected to the positive output end of the operational amplifier; one end of the fourth capacitor is connected to the negative input end of the i-1 th order filter, the other end of the fourth capacitor is connected to one end of the second resistor, and the other end of the second resistor is connected to the negative output end of the operational amplifier.
In another optional implementation manner, the nth order filter includes an i-1 th order filter and an ith order filter, where i has a value in a range of 2, 3, …, N. The i-1 st order filter is a first type filter, and the first type filter comprises: the operational amplifier, the first capacitor and the second capacitor; the positive input end of the operational amplifier is connected to the positive output end of the previous-order filter, the negative input end of the operational amplifier is connected to the negative output end of the previous-order filter, the first output end of the operational amplifier forms the first output end of the filter, one end of the first capacitor is connected to the positive input end of the operational amplifier, and the other end of the first capacitor is connected to the negative output end of the operational amplifier; one end of the second capacitor is connected to the negative input end of the operational amplifier, and the other end of the second capacitor is connected to the positive output end of the operational amplifier. The ith order filter is a second type filter, and the second type filter comprises: the capacitor comprises a third capacitor, a first switch capacitor, a fourth capacitor and a second switch capacitor. One end of the third capacitor is connected to the positive input end of the i-1 th order filter, the other end of the third capacitor is connected to one end of the first switch capacitor, and the other end of the first switch capacitor is connected to the positive output end of the operational amplifier. One end of the fourth capacitor is connected to the negative input end of the i-1 th order filter, the other end of the fourth capacitor is connected to one end of the second switch capacitor, and the other end of the second switch capacitor is connected to the negative output end of the operational amplifier.
Note that the number of filters is not limited in this embodiment.
It should be noted that, in this embodiment, the capacitance values of the third capacitor and the fourth capacitor in the ith order filter, and the capacitance values of the first capacitor and the second capacitor of the i-1 th order filter are all the same.
The amplifying circuit of the embodiment obtains a filtered signal by passing an original audio signal through an N-order filter; the filtering signal passes through a comparator and a digital circuit and then outputs a corresponding digital signal; the number of the operational amplifiers adopted in the N-order filter is smaller than N, and N is a natural number larger than 1. The utility model discloses an amplifying circuit, under the prerequisite of guaranteeing the filtering effect, the quantity through the operational amplifier who uses in reducing the N rank filter reduces the shared circuit area of amplifying circuit and consumption.
EXAMPLE III
Fig. 3 is a schematic structural diagram of an amplifying circuit provided by the third embodiment of the present invention, as shown in fig. 3, the amplifying circuit in this embodiment may include: an N-order filter, a comparator and a digital circuit; after an original audio signal passes through an N-order filter, a filtering signal is obtained; the filtered signal passes through an integrated circuit consisting of a comparator and a digital circuit and then outputs a corresponding digital signal; the number of the operational amplifiers adopted in the N-order filter is smaller than N, and N is a natural number larger than 1.
Referring to fig. 3, a third-order filter is taken as an example for detailed description. The first order filter includes: the positive input end of the first operational amplifier INT1 is connected to the positive output end of the first operational amplifier INT1 through a capacitor, and the negative input end of the first operational amplifier INT1 is connected to the negative output end of the first operational amplifier INT1 through a capacitor. The positive input terminal of the first operational amplifier INT1 constitutes the positive input terminal of the first-order filter, the negative input terminal of the first operational amplifier INT1 constitutes the negative input terminal of the first-order filter, the positive output terminal of the first operational amplifier INT1 constitutes the positive output terminal of the first-order filter, and the negative output terminal of the first operational amplifier INT1 constitutes the negative output terminal of the first-order filter. The second order filter includes: a second operational amplifier INT2, a first capacitor C1, a second capacitor C2; the positive input end of the second operational amplifier INT2 is connected to the positive output end of the previous-order filter, the negative input end of the second operational amplifier INT2 is connected to the negative output end of the previous-order filter, the positive output end of the second operational amplifier INT2 forms the positive output end of the second-order filter, one end of the first capacitor C1 is connected to the positive input end of the second operational amplifier INT2, and the other end of the first capacitor C1 is connected to the negative output end of the second operational amplifier INT 2; one end of the second capacitor C1 is connected to the negative input terminal of the second operational amplifier INT2, the other end of the second capacitor C2 is connected to the positive output terminal of the second amplifier INT2, and the positive output terminal of the second amplifier INT2 constitutes the negative output terminal of the second-order filter. The third order filter includes: a third capacitor C3, a first resistor R1, a fourth capacitor C4 and a second resistor R2; one end of the third capacitor C3 is connected to the positive input end of the second operational amplifier INT2, the other end of the third capacitor C3 is connected to one end of the first resistor R1, and the other end of the first resistor R1 is connected to the positive output end of the second operational amplifier INT 2; one end of the fourth capacitor C4 is connected to the negative input terminal of the second operational amplifier INT2, the other end of the fourth capacitor C4 is connected to one end of the second resistor R2, and the other end of the second resistor R2 is connected to the negative output terminal of the second operational amplifier INT 2.
In an optional implementation manner, if the i-1 st order filter is the first type filter and the i-th order filter is the first type filter, the circuit further includes: a third resistor and a fourth resistor; the positive output end of the operational amplifier in the ith-1 st order filter is connected to the positive input end of the operational amplifier in the ith order filter through a third resistor; and the negative output end of the operational amplifier in the ith-1 st order filter is connected to the negative input end of the operational amplifier in the ith order filter through a fourth resistor.
In another optional implementation manner, if the i-1 st order filter is the first type filter and the i-th order filter is the first type filter, the circuit further includes: a fifth capacitor and a sixth capacitor; one end of a fifth capacitor is connected to the positive output end of the operational amplifier in the ith-1 st order filter, and the other end of the fifth capacitor is connected to the positive input end of the operational amplifier in the ith order filter; one end of the sixth capacitor is connected to the negative output end of the operational amplifier in the ith-1 st order filter, and the other end of the sixth capacitor is connected to the negative input end of the operational amplifier in the ith order filter.
Referring to fig. 3, a third-order filter is taken as an example for detailed description. If the first order filter is a first class filter and the second order filter is a first class filter, the circuit further comprises: a third resistor R3, a fourth resistor R4, a fifth capacitor C5 and a sixth capacitor C6; the positive output end of the operational amplifier in the first-order filter is connected to the positive input end of the operational amplifier in the second-order filter through a third resistor R3; the negative output of the operational amplifier in the first order filter is connected to the negative input of the operational amplifier in the second order filter through a fourth resistor R4. One end of a fifth capacitor C5 is connected to the positive output end of the operational amplifier in the first-order filter, and the other end of the fifth capacitor C5 is connected to the positive input end of the operational amplifier in the second-order filter; one end of the sixth capacitor C6 is connected to the negative output terminal of the operational amplifier in the first-order filter, and the other end of the sixth capacitor C6 is connected to the negative input terminal of the operational amplifier in the second-order filter.
The amplifying circuit of the embodiment obtains a filtered signal by passing an original audio signal through an N-order filter; the filtering signal passes through a comparator and a digital circuit and then outputs a corresponding digital signal; the number of the operational amplifiers adopted in the N-order filter is smaller than N, and N is a natural number larger than 1. The utility model discloses an amplifying circuit, under the prerequisite of guaranteeing the filtering effect, the quantity through the operational amplifier who uses in reducing the N rank filter reduces the shared circuit area of amplifying circuit and consumption.
Example four
Fig. 4 is a schematic structural diagram of an amplifying circuit provided by the fourth embodiment of the present invention, as shown in fig. 4, the amplifying circuit in this embodiment may include: an N-order filter, a weighting adder, a comparator and a digital circuit; after a first path of original audio signal passes through an N-order filter, a filtering signal is obtained; weighting and adding the second path of original audio signal and the filtering signal through a weighting adder to obtain a weighted addition signal; the weighted addition signal passes through the comparator, the digital circuit and the player in sequence to output an audio signal. The filtered signal passes through a comparator and a digital circuit and then outputs a corresponding digital signal; the number of the operational amplifiers adopted in the N-order filter is smaller than N, and N is a natural number larger than 1.
The positive output terminal of the last order filter is connected to the first input port of the first weighted adder, and the negative output terminal of the last order filter is connected to the first input port of the second weighted adder. The second input port of the first weighted adder receives the positive signal Vip of the second audio signal, and the second input port of the second weighted adder receives the negative signal Vin of the second audio signal. The output end of the first weighting adder is connected to the first input end of the integrated circuit formed by the comparator and the digital circuit, and the output end of the second weighting adder is connected to the second input end of the integrated circuit formed by the comparator and the digital circuit. The output end of the integrated circuit formed by the comparator and the digital circuit is connected with the player.
It should be noted that the number of filters in the circuit is not limited in this embodiment.
In an alternative embodiment, the weighted adder comprises: a fifth resistor, a sixth resistor, a seventh resistor, and an eighth resistor; one end of the fifth resistor is connected with the first output end of the last-stage filter, and one end of the sixth resistor is connected with the positive output end of the second path of original audio signals; the other end of the fifth resistor and the other end of the sixth resistor are both connected to a first input end of an integrated circuit consisting of the comparator and the digital circuit; one end of the seventh resistor is connected with the second output end of the last-stage filter, and one end of the eighth resistor is connected with the negative output end of the second path of original audio signals; the other end of the seventh resistor and the other end of the eighth resistor are both connected to a second input end of an integrated circuit formed by the comparator and the digital circuit.
In addition, the resistance values of the fifth resistor, the sixth resistor, the seventh resistor, and the eighth resistor are not limited in this embodiment. The person skilled in the art can adjust the weighted addition ratio of the two audio signals by setting the resistance values of the fifth resistor, the sixth resistor, the seventh resistor and the eighth resistor.
In another alternative embodiment, the weighted adder includes: the third switch capacitor, the fourth switch capacitor, the fifth switch capacitor and the sixth switch capacitor; one end of the third switch capacitor is connected with the first output end of the last-stage filter, and one end of the fourth switch capacitor is connected with the positive output end of the second path of original audio signal; the other end of the third switch capacitor and the other end of the fourth switch capacitor are both connected to a first input end of an integrated circuit consisting of the comparator and the digital circuit; one end of the fifth switch capacitor is connected with the second output end of the last-stage filter, and one end of the sixth switch capacitor is connected with the negative output end of the second path of original audio signal; the other end of the fifth switched capacitor and the other end of the sixth switched capacitor are both connected to a second input end of an integrated circuit formed by the comparator and the digital circuit.
In this embodiment, an original audio signal is divided into two paths, and one path of original audio signal passes through an N-order filter to obtain a filtered signal; the other path of original audio signal is added with the filtering signal in a weighting way through a weighting adder to obtain a weighted addition signal; the weighted addition signal passes through a comparator, a digital circuit and a player in sequence to output an audio signal. Therefore, the linearity of the filtered signal can be improved by using the original audio signal of the other path, and the quality of the output audio signal is improved by performing feedforward processing on the signal entering the comparator and the digital circuit.
In addition, the utility model also provides a playback device, be provided with in this playback device as shown in any one of fig. 1-fig. 4 amplifier circuit.
In the description of the present invention, it is to be understood that the terms "upper", "lower", "front", "rear", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention. In the description of the present invention, "a plurality" means two or more unless specifically stated otherwise.
The terms "first," "second," "third," "fourth," and the like in the description and in the claims of the present application and in the drawings described above, if any, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the application described herein are, for example, capable of operation in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention.
Claims (10)
1. An amplification circuit, comprising: an N-order filter, a comparator and a digital circuit; after an original audio signal passes through the N-order filter, a filtering signal is obtained; the filtering signal passes through the comparator and the digital circuit and then outputs a corresponding digital signal; the number of the operational amplifiers adopted in the N-order filter is smaller than N, and N is a natural number larger than 1.
2. The circuit of claim 1, wherein the nth order filter comprises an ith-1 st order filter and an ith order filter, wherein i has a value in a range of 2, 3, …, N;
the i-1 th order filter is a first type filter, and the first type filter comprises: the operational amplifier, the first capacitor and the second capacitor; the positive input end of the operational amplifier is connected to the positive output end of the previous-order filter, the negative input end of the operational amplifier is connected to the negative output end of the previous-order filter, the first output end of the operational amplifier forms the first output end of the filter, one end of the first capacitor is connected to the positive input end of the operational amplifier, and the other end of the first capacitor is connected to the negative output end of the operational amplifier; one end of the second capacitor is connected to the negative input end of the operational amplifier, and the other end of the second capacitor is connected to the positive output end of the operational amplifier;
the ith order filter is a second type filter, and the second type filter comprises: the first capacitor, the second resistor, the third capacitor and the fourth capacitor are connected in series;
one end of the third capacitor is connected to the positive input end of the i-1 th order filter, the other end of the third capacitor is connected to one end of the first resistor, and the other end of the first resistor is connected to the positive output end of the operational amplifier;
one end of the fourth capacitor is connected to the negative input end of the i-1 th order filter, the other end of the fourth capacitor is connected to one end of the second resistor, and the other end of the second resistor is connected to the negative output end of the operational amplifier.
3. The circuit of claim 1, wherein the nth order filter comprises an ith-1 st order filter and an ith order filter, wherein i has a value in a range of 2, 3, …, N;
the i-1 th order filter is a first type filter, and the first type filter comprises: the operational amplifier, the first capacitor and the second capacitor; the positive input end of the operational amplifier is connected to the positive output end of the previous-order filter, the negative input end of the operational amplifier is connected to the negative output end of the previous-order filter, the first output end of the operational amplifier forms the first output end of the filter, one end of the first capacitor is connected to the positive input end of the operational amplifier, and the other end of the first capacitor is connected to the negative output end of the operational amplifier; one end of the second capacitor is connected to the negative input end of the operational amplifier, and the other end of the second capacitor is connected to the positive output end of the operational amplifier;
the ith order filter is a second type filter, and the second type filter comprises: the first capacitor, the second capacitor, the third capacitor and the fourth capacitor are connected in series;
one end of the third capacitor is connected to the positive input end of the i-1 th order filter, the other end of the third capacitor is connected to one end of the first switch capacitor, and the other end of the first switch capacitor is connected to the positive output end of the operational amplifier;
one end of the fourth capacitor is connected to the negative input end of the i-1 th order filter, the other end of the fourth capacitor is connected to one end of the second switch capacitor, and the other end of the second switch capacitor is connected to the negative output end of the operational amplifier.
4. A circuit according to claim 2 or 3, wherein the capacitance values of the third and fourth capacitors of the ith order filter and the first and second capacitors of the (i-1) th order filter are the same.
5. A circuit according to claim 2 or 3, wherein if the i-1 st order filter is a first type filter and the i-th order filter is a first type filter, the circuit further comprises: a third resistor and a fourth resistor;
the positive output end of the operational amplifier in the ith-1 st order filter is connected to the positive input end of the operational amplifier in the ith order filter through the third resistor;
and the negative output end of the operational amplifier in the ith-1 st order filter is connected to the negative input end of the operational amplifier in the ith order filter through the fourth resistor.
6. The circuit of claim 5, further comprising: a fifth capacitor and a sixth capacitor;
one end of the fifth capacitor is connected to the positive output end of the operational amplifier in the ith-1 st order filter, and the other end of the fifth capacitor is connected to the positive input end of the operational amplifier in the ith order filter;
one end of the sixth capacitor is connected to the negative output end of the operational amplifier in the ith-1 st order filter, and the other end of the sixth capacitor is connected to the negative input end of the operational amplifier in the ith order filter.
7. The circuit of claim 1, further comprising: the weighted adder divides the original audio signals into two paths, and a first path of original audio signals pass through the N-order filter to obtain filtered signals; and the second path of original audio signal is subjected to weighted addition with the filtering signal through the weighted adder to obtain a weighted addition signal, and the weighted addition signal passes through the comparator and the digital circuit to output a corresponding digital signal.
8. The circuit of claim 7, wherein the weighted adder comprises: a fifth resistor, a sixth resistor, a seventh resistor, and an eighth resistor;
one end of the fifth resistor is connected with the first output end of the last-order filter, and one end of the sixth resistor is connected with the positive output end of the second path of original audio signals; the other end of the fifth resistor and the other end of the sixth resistor are both connected to a first input end of an integrated circuit formed by the comparator and the digital circuit;
one end of the seventh resistor is connected with the second output end of the last-order filter, and one end of the eighth resistor is connected with the negative output end of the second path of original audio signal; the other end of the seventh resistor and the other end of the eighth resistor are both connected to a second input end of an integrated circuit formed by the comparator and the digital circuit.
9. The circuit of claim 7, wherein the weighted adder comprises: the third switch capacitor, the fourth switch capacitor, the fifth switch capacitor and the sixth switch capacitor;
one end of the third switched capacitor is connected with the first output end of the last-stage filter, and one end of the fourth switched capacitor is connected with the positive output end of the second path of original audio signal; the other end of the third switch capacitor and the other end of the fourth switch capacitor are both connected to a first input end of an integrated circuit formed by the comparator and the digital circuit;
one end of the fifth switch capacitor is connected with the second output end of the last-stage filter, and one end of the sixth switch capacitor is connected with the negative output end of the second path of original audio signal; the other end of the fifth switch capacitor and the other end of the sixth switch capacitor are both connected to a second input end of an integrated circuit formed by the comparator and the digital circuit.
10. A playback device, characterized by comprising an amplification circuit as claimed in any one of claims 1 to 9.
Priority Applications (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201922370332.XU CN210518805U (en) | 2019-12-25 | 2019-12-25 | Amplifying circuit and playing device |
| PCT/CN2020/116583 WO2021128993A1 (en) | 2019-12-25 | 2020-09-21 | Amplifier circuit, and playing apparatus |
| US17/849,599 US20220329218A1 (en) | 2019-12-25 | 2022-06-25 | Audio amplifying circuit and playing device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201922370332.XU CN210518805U (en) | 2019-12-25 | 2019-12-25 | Amplifying circuit and playing device |
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| CN210518805U true CN210518805U (en) | 2020-05-12 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201922370332.XU Active CN210518805U (en) | 2019-12-25 | 2019-12-25 | Amplifying circuit and playing device |
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| WO (1) | WO2021128993A1 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2021128991A1 (en) * | 2019-12-25 | 2021-07-01 | 锐迪科微电子（上海）有限公司 | Audio amplification circuit and playback device |
| WO2021128993A1 (en) * | 2019-12-25 | 2021-07-01 | 锐迪科微电子（上海）有限公司 | Amplifier circuit, and playing apparatus |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1713515B (en) * | 2004-06-25 | 2010-08-11 | 盛群半导体股份有限公司 | Digital medium-frequency discriminator |
| CN102832893B (en) * | 2012-09-25 | 2015-07-08 | 上海贝岭股份有限公司 | D-type power amplifier |
| CN103441739B (en) * | 2013-08-21 | 2015-04-22 | 昂宝电子（上海）有限公司 | Amplification system with one or more channels and amplification method |
| CN109995364B (en) * | 2019-03-06 | 2020-08-04 | 杭州城芯科技有限公司 | Frequency synthesizer based on digital temperature compensation circuit |
| CN210518805U (en) * | 2019-12-25 | 2020-05-12 | 锐迪科微电子（上海）有限公司 | Amplifying circuit and playing device |
-
2019
- 2019-12-25 CN CN201922370332.XU patent/CN210518805U/en active Active
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2021128991A1 (en) * | 2019-12-25 | 2021-07-01 | 锐迪科微电子（上海）有限公司 | Audio amplification circuit and playback device |
| WO2021128993A1 (en) * | 2019-12-25 | 2021-07-01 | 锐迪科微电子（上海）有限公司 | Amplifier circuit, and playing apparatus |
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| WO2021128993A1 (en) | 2021-07-01 |
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