Signal processing circuit and Hall detection device

Abstract

The utility model discloses a signal processing circuit and a Hall detection device. The signal processing circuit comprises a chopper circuit; the input end of the chopper circuit is connected with the Hall sensing circuit to receive the Hall sensing analog signal, the amplifying circuit is used for amplifying the Hall sensing analog signal, and the chopper circuit is used for chopping the amplified Hall sensing analog signal to output a corresponding signal; the input end of the delta-sigma modulation circuit is connected with the output end of the chopper circuit; and the input end of the digital filter circuit is connected with the output end of the delta-sigma modulation circuit, and the output end of the digital filter circuit is used for outputting a Hall sensing digital signal. Based on the above mode, the occupied space of the signal processing circuit can be reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of sensing signal processing, in particular to a signal processing circuit and a Hall detection device. BACKGROUND

[0002] In the prior art, in the use of Hall devices, it is usually necessary to use a chopper circuit to carry the offset voltage signal generated by the Hall device or the offset voltage signal generated by amplifying the signal of the Hall device to the chopping frequency of the chopper circuit, and then use an analog filter to perform low-pass filtering to filter out the offset voltage signal carried to the relatively high frequency chopping frequency.

[0003] The defect of the prior art is that the analog filter used for low-pass filtering requires a large number of devices and a relatively complex circuit, resulting in a large occupied space required by the analog filter, and thus a large occupied space of the signal processing circuit where the analog filter is located. CONTENT OF THE UTILITY MODEL

[0004] The technical problem solved by the present application is how to reduce the occupied space of the signal processing circuit.

[0005] To solve the above technical problem, the first technical solution adopted by the present application is: a signal processing circuit, comprising: a chopper circuit; an amplification circuit, the input end of the chopper circuit being connected to a Hall sensing circuit to receive a Hall sensing analog signal, the amplification circuit being used for amplifying and processing the Hall sensing analog signal, the chopper circuit being used for chopping processing the Hall sensing analog signal after amplification to output a corresponding signal; a triangular integral modulation circuit, the input end of the triangular integral modulation circuit being connected to the output end of the chopper circuit; a digital filter circuit, the input end of the digital filter circuit being connected to the output end of the triangular integral modulation circuit, the output end of the digital filter circuit being used for outputting a Hall sensing digital signal.

[0006] The chopper circuit comprises: a first chopper circuit, the input end of the first chopper circuit being used for connecting the Hall sensing circuit to receive the Hall sensing analog signal, the output end of the first chopper circuit being connected to the input end of the amplification circuit; a second chopper circuit, the input end of the second chopper circuit being connected to the output end of the amplification circuit, the output end of the second chopper circuit being connected to the input end of the triangular integral modulation circuit.

[0007] The triangular integral modulation circuit comprises an M-order N-bit triangular integral modulator; wherein M is a positive integer, and N is a positive integer.

[0008] The M-order N-bit triangular integration modulator comprises at least one set of triangular integration modulation sub-circuits, a quantizer, and a gain adjuster.

[0009] The chopping circuit comprises a first chopping circuit and a second chopping circuit; the power supply end of the Hall sensing circuit is configured to receive a power supply voltage, the ground end of the Hall sensing circuit is configured to receive a ground voltage, the first output end of the Hall sensing circuit is connected to the first input end of the first chopping circuit, and the second output end of the Hall sensing circuit is connected to the second input end of the first chopping circuit; the first input end of the amplification circuit is connected to the first output end of the first chopping circuit, and the second input end of the amplification circuit is connected to the second output end of the first chopping circuit; the first input end of the second chopping circuit is connected to the first output end of the amplification circuit, and the second input end of the second chopping circuit is connected to the second output end of the amplification circuit; the first input end of the triangular integration modulation circuit is connected to the first output end of the second chopping circuit, and the second input end of the triangular integration modulation circuit is connected to the second output end of the second chopping circuit; the first input end of the digital filter circuit is connected to the first output end of the triangular integration modulation circuit, and the second input end of the digital filter circuit is connected to the second output end of the triangular integration modulation circuit.

[0010] The chopper circuit includes a first switch, a second switch, a third switch and a fourth switch; the input end of the first switch and the input end of the second switch are both the first input end of the chopper circuit, the input end of the third switch and the input end of the fourth switch are both the second input end of the chopper circuit; the output end of the first switch and the output end of the third switch are both the first output end of the chopper circuit, and the output end of the second switch and the output end of the fourth switch are both the second output end of the chopper circuit; the first switch and the third switch are both the first type switch, and the second switch and the fourth switch are both the second type switch, and the first type switch and the second type switch are alternately turned on.

[0011] The amplification circuit includes at least one full differential operational amplifier.

[0012] The triangular integral modulation circuit is used to perform triangular integral modulation processing on the corresponding signal output after the chopping processing to output the corresponding signal.

[0013] In order to solve the above technical problems, the second technical scheme adopted by the present application is: a Hall detection device, comprising: a Hall sensing circuit; the signal processing circuit, the signal processing circuit is connected to the Hall sensing circuit.

[0014] The beneficial effects of the present application are that: different from the prior art, in the technical scheme of the present application, the signal processing circuit includes a chopper circuit, an amplification circuit, a triangular integral modulation circuit and a digital filter circuit, the input end of the chopper circuit is connected to the Hall sensing circuit to receive the Hall sensing analog signal, the amplification circuit is used to amplify the Hall sensing analog signal, the chopper circuit is used to chop the amplified Hall sensing analog signal to output the corresponding signal, the input end of the triangular integral modulation circuit is connected to the output end of the chopper circuit, the input end of the digital filter circuit is connected to the output end of the triangular integral modulation circuit, and the output end of the digital filter circuit is used to output the Hall sensing digital signal. Based on the above-mentioned mode, by adopting the triangular integral modulation circuit and the digital filter, the analog signal output by the chopper circuit can be converted into a digital signal by using the triangular integral modulation circuit, and then the digital signal is low-pass filtered by using the digital filter, so that the offset voltage signal part of the analog signal, which is moved to a higher chopping frequency by the chopper circuit, can be filtered out. The occupied space of the triangular integral modulation circuit and the digital filter is smaller than that of the analog filter, thereby reducing the occupied space of the signal processing circuit in which the analog filter is located. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments will be briefly introduced. Obviously, the drawings in the following description only relate to some embodiments of the present application, and all other drawings obtained by those of ordinary skill in the art without any creative effort based on these drawings also fall within the protection scope of the present application.

[0016] Figure 1 is a structural schematic diagram of an embodiment of the signal processing circuit of the present application;

[0017] Figure 2 is a structural schematic diagram of an embodiment of the chopper circuit of the present application;

[0018] Figure 3 is a waveform schematic diagram of an embodiment of the control signal of the present application;

[0019] Figure 4 is a structural schematic diagram of an embodiment of the triangle integral modulation circuit of the present application;

[0020] Figure 5 is a structural schematic diagram of an embodiment of the Hall detection device of the present application.

[0021] The reference signs are as follows: 10, Hall sensing circuit; 20, signal processing circuit; 21, chopper circuit; 211, first chopper circuit; 212, second chopper circuit; 2101, first switch; 2102, second switch; 2103, third switch; 2104, fourth switch; 22, amplification circuit; 221, full differential operational amplifier; 23, triangle integral modulation circuit; 231, first adder; 232, first gain device; 233, first integrator; 234, second adder; 235, second gain device; 236, second integrator; 237, quantizer; 24, digital filter circuit. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present application will be described clearly and completely in combination with the drawings of the embodiments of the present application. It can be understood that the specific embodiments described herein are only used to explain the present application, but not to limit the present application. In addition, it should be noted that, for the convenience of description, only the parts related to the present application are shown in the drawings, but not all the structures. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without any creative effort fall within the protection scope of the present application.

[0023] The terms "first", "second", "third", etc. are used only for descriptive purposes and are not to be construed as indicating or implying relative importance or a specific number of the technical features indicated. Thus, features defined with "first", "second", "third" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise explicitly and specifically limited. All directional indications (such as upper, lower, left, right, front, rear, etc.) in the embodiments of the present application are only used to explain the relative position relationship between the components, the movement condition, etc. between the components in a certain posture (as shown in the drawings), and if the certain posture changes, the directional indications also change accordingly. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but can optionally include steps or units not listed, or can optionally include other steps or units inherent to the process, method, product or device.

[0024] Reference herein to "embodiments" means that a particular feature, structure, or characteristic described in connection with an embodiment can be included in at least one embodiment of the application. The appearance of the phrase in various places in the specification does not necessarily all refer to the same embodiment, nor does it necessarily refer to a separate or alternative embodiment. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with each other.

[0025] The present application proposes a signal processing circuit, referring to Figure 1 , Figure 1 is a structural schematic diagram of an embodiment of the signal processing circuit of the present application, as Figure 1 shown, the signal processing circuit includes a chopper circuit 21, an amplification circuit 22, a triangular integral modulation circuit 23 and a digital filter circuit 24.

[0026] The input end of the chopper circuit 21 is connected to the Hall sensing circuit 10 to receive the Hall sensing analog signal, the amplification circuit 22 is used for amplifying the Hall sensing analog signal, the chopper circuit 21 is used for chopping the amplified Hall sensing analog signal to output a corresponding signal.

[0027] The first chopping processing of the received Hall sensor analog signal can be performed by the chopping circuit 21, the Hall sensor analog signal after the first chopping processing can be amplified by the amplification circuit 22, and then the second chopping processing of the Hall sensor analog signal after the amplification can be performed by the chopping circuit 21, so as to move the frequency of the offset voltage signal caused by the Hall sensor circuit 10 and the amplification circuit 22 to the chopping frequency of the chopping circuit 21, and the chopping frequency is higher than the original frequency of the offset voltage signal, and then the offset voltage signal can be removed by the subsequent low-pass filtering processing.

[0028] The input end of the triangular integral modulation circuit 23 is connected to the output end of the chopping circuit 21.

[0029] The input end of the digital filter circuit 24 is connected to the output end of the triangular integral modulation circuit 23, and the output end of the digital filter circuit 24 is used to output the Hall sensor digital signal.

[0030] The triangular integral modulation circuit 23 can be a Sigma-Delta modulator in a Sigma-Delta analog-to-digital converter, and the digital filter circuit 24 can be a digital filter in the Sigma-Delta analog-to-digital converter. The triangular integral modulation circuit 23 can be used to perform analog-to-digital conversion on the received signal, and move the frequency of the quantization noise generated in the analog-to-digital conversion to a higher frequency. Then, the digital filter circuit 24 is used for low-pass filtering, which can remove the quantization noise and the offset voltage signal whose frequency is moved to a higher chopping frequency. In this way, the offset voltage can be removed without using an analog filter occupying a large space, and the space occupied by the signal processing circuit of the analog filter is reduced, and the applicability of the signal processing circuit is improved.

[0031] Unlike existing technologies, the signal processing circuit in this application includes a chopper circuit, an amplifier circuit, a trigonometric modulation circuit, and a digital filter circuit. The input of the chopper circuit is connected to a Hall sensor circuit to receive the Hall sensor analog signal. The amplifier circuit amplifies the Hall sensor analog signal, and the chopper circuit chops the amplified Hall sensor analog signal to output a corresponding signal. The input of the trigonometric modulation circuit is connected to the output of the chopper circuit, and the input of the digital filter circuit is connected to the output of the trigonometric modulation circuit. The output of the digital filter circuit outputs the Hall sensor digital signal. Based on the above approach, by using a trigonometric modulation circuit and a digital filter, the analog signal output by the chopper circuit can be converted into a digital signal using the trigonometric modulation circuit, and then the digital signal can be low-pass filtered using the digital filter. This removes the offset voltage signal portion of the analog signal that has been shifted to a higher chopping frequency by the chopper circuit. Furthermore, the space occupied by the trigonometric modulation circuit and the digital filter is smaller than that occupied by the analog filter, reducing the space occupied by the signal processing circuit containing the analog filter.

[0032] In one embodiment, such as Figure 1 As shown, the chopper circuit 21 includes a first chopper circuit 211 and a second chopper circuit 212.

[0033] The input terminal of the first chopper circuit 211 is connected to the Hall sensor circuit 10 to receive the Hall sensor analog signal, and the output terminal of the first chopper circuit 211 is connected to the input terminal of the amplifier circuit 22.

[0034] The input terminal of the second chopper circuit 212 is connected to the output terminal of the amplifier circuit 22, and the output terminal of the second chopper circuit 212 is connected to the input terminal of the trigonometric integral modulation circuit 23.

[0035] Specifically, the first chopper circuit 211 can be used to perform the first chopper described above, and the second chopper circuit 212 can be used to perform the second chopper described above.

[0036] Based on the first chopping and the second chopping described above, the frequency of the offset voltage signal in the Hall sensor analog signal can be increased, and then the low-pass filter of the digital filter circuit 24 can be used to remove the offset voltage signal with increased frequency.

[0037] In one embodiment, see Figure 2 , Figure 2 This is a schematic diagram of the structure of one embodiment of the chopper circuit of this application, as shown below. Figure 2 As shown, the chopper circuit 21 includes a first switch 2101, a second switch 2102, a third switch 2103, and a fourth switch 2104.

[0038] The input end of the first switch 2101 and the input end of the second switch 2102 are both first input ends of the chopper circuit 21, and the input end of the third switch 2103 and the input end of the fourth switch 2104 are both second input ends of the chopper circuit 21.

[0039] The output end of the first switch 2101 and the output end of the third switch 2103 are both first output ends of the chopper circuit 21, and the output end of the second switch 2102 and the output end of the fourth switch 2104 are both second output ends of the chopper circuit 21.

[0040] The first switch 2101 and the third switch 2103 are both first type switches, and the second switch 2102 and the fourth switch 2104 are both second type switches, and the first type switches and the second type switches are alternately turned on.

[0041] Specifically, as shown in Figure 2 when the chopper circuit 21 includes a first chopper circuit 211 and a second chopper circuit 212, the first chopper circuit 211 and the second chopper circuit 212 are both sub-chopper circuits.

[0042] Each sub-chopper circuit can include a group of switches of the first switch 2101, the second switch 2102, the third switch 2103 and the fourth switch 2104.

[0043] The input end of the first switch 2101 and the input end of the second switch 2102 are both first input ends of the corresponding sub-chopper circuit, and the input end of the third switch 2103 and the input end of the fourth switch 2104 are both second input ends of the corresponding sub-chopper circuit.

[0044] The output end of the first switch 2101 and the output end of the third switch 2103 are both first output ends of the corresponding sub-chopper circuit, and the output end of the second switch 2102 and the output end of the fourth switch 2104 are both second output ends of the corresponding sub-chopper circuit.

[0045] The first switch 2101 and the third switch 2103 are both first type switches, and the second switch 2102 and the fourth switch 2104 are both second type switches, and the first type switches and the second type switches are alternately turned on.

[0046] Referring to Figure 3 , Figure 3 is a waveform diagram of an embodiment of the control signal of the present application, as Figure 3As shown, S1 can be specifically a switch control signal received by the first type switch, S2 can be specifically a switch control signal received by the second type switch, the switch can enter the first switch state when the received switch control signal is at a high level, and enter the second switch state when the received switch control signal is at a low level, the first switch state and the second switch state are one-to-one corresponding to the off state and the on state, based on this mode, the first type switch and the second type switch can be alternately turned on and alternately turned off, S1 and S2 can be specifically inverse signals with equal duty cycles.

[0047] As shown Figure 3 As shown, S3 can be specifically a signal obtained after amplification processing and chopper processing, and S4 can be a sampling control signal for controlling the triangular integration modulation circuit 23 to sample the signal obtained after amplification processing and chopper processing, when S1 and S2 switch their high and low levels, S3 will have a corresponding level establishment process, which has a certain establishment time, S4 can be used to control the triangular integration modulation circuit 23 to sample the signal only after S3 completes the establishment of a level and before the establishment of the next level starts, so as to perform corresponding analog-to-digital conversion processing, that is, the triangular integration modulation circuit 23 can be used to perform triangular integration modulation processing to output the corresponding signal after the signal output after chopper processing is established, thereby reducing the possibility of error caused by the triangular integration modulation circuit 23 based on the unestablished level for analog-to-digital conversion, and improving the reliability of the signal processing circuit.

[0048] In an embodiment, the triangular integration modulation circuit includes an M-order N-bit triangular integration modulator.

[0049] Wherein, M is a positive integer, and N is a positive integer.

[0050] Specifically, the triangular integration modulation circuit can set the required order and the required processing bits of the triangular integration modulator as needed, and in addition, a feedback type triangular integration modulator or a feedforward type triangular integration modulator can be set according to actual needs, which is not limited here.

[0051] Specifically, the M-order N-bit triangular integration modulator can include at least one group of triangular integration modulation sub-circuit and quantizer.

[0052] A single triangular integration modulation sub-circuit can include an adder, a gain amplifier and an integrator, the first input end of the adder is the input end of the single triangular integration modulation sub-circuit, the input end of the gain amplifier is connected to the output end of the adder, the input end of the integrator is connected to the output end of the gain amplifier, and the output end of the integrator is the output end of the single triangular integration modulation sub-circuit.

[0053] The input end of the quantizer is connected to the output end of the at least one group of triangular integral modulation sub-circuits, and the output end of the quantizer is connected to the second input end of the adder.

[0054] When the at least one group of triangular integral modulation sub-circuits includes one triangular integral modulation sub-circuit, the input end of the one triangular integral modulation sub-circuit is the input end of the at least one group of triangular integral modulation sub-circuits, and the output end of the one triangular integral modulation sub-circuit is the output end of the at least one group of triangular integral modulation sub-circuits.

[0055] When the at least one group of triangular integral modulation sub-circuits includes two or more triangular integral modulation sub-circuits, the two or more triangular integral modulation sub-circuits are sequentially connected in cascade, and in the adjacent two triangular integral modulation sub-circuits, the output end of the first triangular integral modulation sub-circuit is connected to the input end of the second triangular integral modulation sub-circuit.

[0056] The input end of the first triangular integral modulation sub-circuit in the two or more triangular integral modulation sub-circuits is the input end of the at least one group of triangular integral modulation sub-circuits, and the output end of the last triangular integral modulation sub-circuit in the two or more triangular integral modulation sub-circuits is the output end of the at least one group of triangular integral modulation sub-circuits.

[0057] In the at least one group of triangular integral modulation sub-circuits, the more the number of triangular integral modulation sub-circuits, the higher the order of the triangular integral modulation circuit formed, which can be determined according to actual requirements.

[0058] Based on the above mode, the corresponding triangular integral modulation circuit can be constructed according to actual requirements to perform corresponding digital modulation, thereby improving the flexibility of the signal processing circuit.

[0059] Optionally, taking the M-order N-bit triangular integral modulator as an example, the 2-order 1-bit feedback type triangular integral modulator, the at least one group of triangular integral modulation sub-circuits includes two triangular integral modulation sub-circuits, and each triangular integral modulation sub-circuit includes a corresponding adder, a gain device and an integrator, as shown in Figure 4 , Figure 4 is a structural schematic diagram of an embodiment of the triangular integral modulation circuit of the present application, as shown in Figure 4 The triangular integral modulation circuit 23 includes a first adder 231, a first gain device 232, a first integrator 233, a second adder 234, a second gain device 235, a second integrator 236 and a quantizer 237.

[0060] The first input end of the first adder 231 is the input end of the triangular integral modulation circuit 23.

[0061] The input end of the first gain device 232 is connected to the output end of the adder.

[0062] An input terminal of the first integrator 233 is connected to an output terminal of the first gain device 232.

[0063] A first input terminal of the second adder 234 is connected to an output terminal of the first integrator 233.

[0064] An input terminal of the second gain device 235 is connected to an output terminal of the second adder 234.

[0065] An input terminal of the second integrator 236 is connected to an output terminal of the second gain device 235.

[0066] An input terminal of the quantizer 237 is connected to an output terminal of the second integrator 236, and an output terminal of the quantizer 237 is an output terminal of the triangular integrator modulation circuit 23. The output terminal of the triangular integrator modulation circuit 23 is respectively connected to a second input terminal of the first adder 231 and a second input terminal of the second adder 234.

[0067] Specifically, u can refer to a signal received by an input terminal of the triangular integrator modulation circuit 23, and v can refer to a signal output by an output terminal of the triangular integrator modulation circuit 23.

[0068] The gain value of the first gain device 232 can be a, and the gain value of the second gain device 235 can be b.

[0069] The triangular integrator modulation circuit 23 formed based on the above structure can increase the frequency of quantization noise generated in the analog-to-digital conversion while converting the received analog signal into a digital signal, so as to remove the quantization noise when the subsequent digital filter circuit 24 performs low-pass filtering.

[0070] It should be noted that the above is an example of a 2-order 1-bit feedback type triangular integrator modulator of an M-order N-bit triangular integrator modulator. In other examples, m and n can also be other values, and the feedback type triangular integrator modulator can be replaced by a feedforward type triangular integrator modulator. The specific type can be determined according to actual needs, which is not limited here.

[0071] In an embodiment, the digital filter circuit 24 is a low-pass filter.

[0072] Specifically, based on the low-pass filter, the frequency-increased offset voltage signal and / or the frequency-increased quantization noise existing in the received signal can be removed, so as to remove the offset voltage signal using only a digital filter without using an analog filter, thereby reducing the size of the signal processing circuit and improving the use flexibility.

[0073] In an embodiment, as shown in FIG. 2, the chopper circuit 21 includes a first chopper circuit 211 and a second chopper circuit 212. Figure 1 The first chopper circuit 211 includes a first comparator 2111, a first capacitor 2112, a first resistor 2113, a first diode 2114, and a first switch 2115.

[0074] The power supply end of the Hall sensing circuit 10 is configured to receive a power supply voltage, the ground end of the Hall sensing circuit 10 is configured to receive a ground voltage, the first output end of the Hall sensing circuit 10 is connected to the first input end of the first chopping circuit 211, and the second output end of the Hall sensing circuit 10 is connected to the second input end of the first chopping circuit 211.

[0075] The first input end of the amplification circuit 22 is connected to the first output end of the first chopping circuit 211, and the second input end of the amplification circuit 22 is connected to the second output end of the first chopping circuit 211.

[0076] The first input end of the second chopping circuit 212 is connected to the first output end of the amplification circuit 22, and the second input end of the second chopping circuit 212 is connected to the second output end of the amplification circuit 22.

[0077] The first input end of the triangular integral modulation circuit 23 is connected to the first output end of the second chopping circuit 212, and the second input end of the triangular integral modulation circuit 23 is connected to the second output end of the second chopping circuit 212.

[0078] The first input end of the digital filter circuit 24 is connected to the first output end of the triangular integral modulation circuit 23, and the second input end of the digital filter circuit 24 is connected to the second output end of the triangular integral modulation circuit 23.

[0079] Specifically, the first output end of the Hall sensing circuit 10 and the second output end of the Hall sensing circuit 10 are configured to jointly output a Hall sensing analog signal, the first output end of the first chopping circuit 211 and the second output end of the first chopping circuit 211 are configured to jointly output a Hall sensing analog signal after first chopping processing, the first output end of the amplification circuit 22 and the second output end of the amplification circuit 22 are configured to jointly output a Hall sensing analog signal after first chopping processing and amplification processing, the first output end of the second chopping circuit 212 and the second output end of the second chopping circuit 212 are configured to jointly output a Hall sensing analog signal after first chopping processing, amplification processing and second chopping processing, and the triangular integral modulation circuit 23 and the digital filter circuit 24 are configured to perform analog-to-digital conversion processing and low-pass filtering processing on the Hall sensing analog signal after first chopping processing, amplification processing and second chopping processing, and finally output a Hall sensing digital signal based on the output end of the digital filter circuit 24.

[0080] In an embodiment, the amplification circuit 22 includes at least one fully differential operational amplifier 221.

[0081] Specifically, the amplification circuit 22 can specifically include only one fully differential operational amplifier 221, and each input end or output end of the fully differential operational amplifier 221 is the corresponding input end or output end of the amplification circuit 22.

[0082] The amplification circuit 22 can specifically include at least two fully differential operational amplifiers 221, and the amplification circuit 22 with a corresponding amplification multiple is built based on the cascade of the at least two fully differential operational amplifiers 221.

[0083] The above are all examples, and the number of the fully differential operational amplifiers 221 included in the amplification circuit 22 can be determined according to actual needs, which is not limited here.

[0084] The present application also proposes a Hall detection device, referring to Figure 5 , Figure 5 is a structural schematic diagram of an embodiment of the Hall detection device of the present application, as Figure 5 shown, the Hall detection device 30 includes a Hall sensing circuit 10 and a signal processing circuit 20, and the signal processing circuit 20 is connected to the Hall sensing circuit 10.

[0085] Different from the prior art, in the technical solution of the present application, the signal processing circuit includes a chopper circuit, an amplification circuit, a triangular integral modulation circuit and a digital filter circuit, the input end of the chopper circuit is connected to the Hall sensing circuit to receive a Hall sensing analog signal, the amplification circuit is used for amplifying and processing the Hall sensing analog signal, the chopper circuit is used for chopping processing the Hall sensing analog signal after amplification processing to output a corresponding signal, the input end of the triangular integral modulation circuit is connected to the output end of the chopper circuit, the input end of the digital filter circuit is connected to the output end of the triangular integral modulation circuit, and the output end of the digital filter circuit is used for outputting a Hall sensing digital signal. Based on the above-mentioned manner, by adopting the triangular integral modulation circuit and the digital filter, the analog signal output by the chopper circuit is first converted into a digital signal by the triangular integral modulation circuit, and then the digital signal is low-pass filtered by the digital filter, so that the offset voltage signal part in the analog signal, which is moved to a higher chopping frequency by the chopper circuit, can be filtered out. The occupied space of the triangular integral modulation circuit and the digital filter is smaller than that of the analog filter, thereby reducing the occupied space of the signal processing circuit where the analog filter is located.

[0086] The above-mentioned are only embodiments of the present application, and do not limit the patent scope of the present application, and any equivalent structure or equivalent flow transformation by using the content of the specification and drawings of the present application, or direct or indirect application in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A signal processing circuit, characterized in that, include: Chopper circuit; An amplifier circuit is provided, wherein the input terminal of the chopper circuit is connected to a Hall sensor circuit to receive a Hall sensor analog signal, the amplifier circuit is used to amplify the Hall sensor analog signal, and the chopper circuit is used to chop the amplified Hall sensor analog signal to output a corresponding signal. A triangular integral modulation circuit, wherein the input terminal of the triangular integral modulation circuit is connected to the output terminal of the chopper circuit; A digital filtering circuit is provided, wherein the input terminal of the digital filtering circuit is connected to the output terminal of the trigonometric integral modulation circuit, and the output terminal of the digital filtering circuit is used to output a Hall sensor digital signal.

2. The signal processing circuit according to claim 1, characterized in that, The chopper circuit includes: A first chopper circuit, the input terminal of which is connected to a Hall sensor circuit to receive Hall sensor analog signals, and the output terminal of which is connected to the input terminal of the amplifier circuit. The second chopper circuit has its input terminal connected to the output terminal of the amplifier circuit, and its output terminal connected to the input terminal of the trigonometric integral modulation circuit.

3. The signal processing circuit according to claim 1 or 2, characterized in that, The trigonometric integral modulation circuit includes an M-order N-bit trigonometric integral modulator. Where M is a positive integer and N is a positive integer.

4. The signal processing circuit according to claim 3, characterized in that, The M-order N-bit trigonometric integral modulator specifically includes: At least one set of trigonometric integral modulation sub-circuits, the trigonometric integral modulation sub-circuit includes an adder, a gainer and an integrator, the first input terminal of the adder is the input terminal of the trigonometric integral modulation sub-circuit, the input terminal of the gainer is connected to the output terminal of the adder, the input terminal of the integrator is connected to the output terminal of the gainer, and the output terminal of the integrator is the output terminal of the trigonometric integral modulation sub-circuit; A quantizer, the input of which is connected to the output of the at least one set of trigonometric integral modulation sub-circuits, and the output of which is connected to the second input of the adder; Wherein, when the at least one set of trigonometric integral modulation sub-circuits includes one trigonometric integral modulation sub-circuit, the input terminal of the one trigonometric integral modulation sub-circuit is the input terminal of the at least one set of trigonometric integral modulation sub-circuits, and the output terminal of the one trigonometric integral modulation sub-circuit is the output terminal of the at least one set of trigonometric integral modulation sub-circuits. When the at least one set of trigonometric integral modulation sub-circuits includes two or more trigonometric integral modulation sub-circuits, the two or more trigonometric integral modulation sub-circuits are cascaded in sequence, the input terminal of the first trigonometric integral modulation sub-circuit among the two or more trigonometric integral modulation sub-circuits is the input terminal of the at least one set of trigonometric integral modulation sub-circuits, and the output terminal of the last trigonometric integral modulation sub-circuit among the two or more trigonometric integral modulation sub-circuits is the output terminal of the at least one set of trigonometric integral modulation sub-circuits.

5. The signal processing circuit according to claim 1 or 2, characterized in that, The digital filtering circuit is a low-pass filter.

6. The signal processing circuit according to claim 1 or 2, characterized in that, The chopper circuit includes a first chopper circuit and a second chopper circuit. The power supply terminal of the Hall sensor circuit is used to receive the power supply voltage, the ground terminal of the Hall sensor circuit is used to receive the ground voltage, the first output terminal of the Hall sensor circuit is connected to the first input terminal of the first chopper circuit, and the second output terminal of the Hall sensor circuit is connected to the second input terminal of the first chopper circuit. The first input terminal of the amplifier circuit is connected to the first output terminal of the first chopper circuit, and the second input terminal of the amplifier circuit is connected to the second output terminal of the first chopper circuit. The first input terminal of the second chopper circuit is connected to the first output terminal of the amplifier circuit, and the second input terminal of the second chopper circuit is connected to the second output terminal of the amplifier circuit. The first input terminal of the triangular integral modulation circuit is connected to the first output terminal of the second chopper circuit, and the second input terminal of the triangular integral modulation circuit is connected to the second output terminal of the second chopper circuit. The first input terminal of the digital filter circuit is connected to the first output terminal of the trigonometric integral modulation circuit, and the second input terminal of the digital filter circuit is connected to the second output terminal of the trigonometric integral modulation circuit.

7. The signal processing circuit according to claim 1 or 2, characterized in that, The chopper circuit includes a first switch, a second switch, a third switch, and a fourth switch; The input terminals of the first switch and the second switch are both the first input terminals of the chopper circuit, and the input terminals of the third switch and the fourth switch are both the second input terminals of the chopper circuit. The output terminals of the first switch and the third switch are both the first output terminals of the chopper circuit, and the output terminals of the second switch and the fourth switch are both the second output terminals of the chopper circuit. The first switch and the third switch are both type 1 switches, and the second switch and the fourth switch are both type 2 switches. The first type switch and the second type switch are alternately turned on.

8. The signal processing circuit according to claim 1 or 2, characterized in that, The amplifier circuit includes at least one fully differential operational amplifier.

9. The signal processing circuit according to claim 1 or 2, characterized in that, The trigonometric integral modulation circuit is used to perform trigonometric integral modulation processing after the corresponding signal output after the chopping process is established, so as to output the corresponding signal.

10. A Hall effect detection device, characterized in that, include: Hall effect sensor circuit; The signal processing circuit according to any one of claims 1 to 9, wherein the signal processing circuit is connected to the Hall sensor circuit.

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