Signal measurement circuits and devices

Abstract

The present invention relates to a signal measurement circuit, comprising a reference resistor network module, a first signal amplification module, a bias test module, a second signal amplification module and a spectrum reconstruction module, wherein the reference resistor network module is used to generate a first reference noise signal and a second reference noise signal that are differential signals from each other; the first signal amplification module is connected to the reference resistor network module and is used to generate a reference loop noise signal with a preset amplification factor based on the first reference noise signal and the second reference noise signal; the bias test module is used to generate a noise signal to be measured and a reference noise signal that are differential signals from each other; the second signal amplification module is connected to the bias test module and is used to generate a test loop noise signal with a preset amplification factor based on the noise signal to be measured and the reference noise signal; and the spectrum reconstruction module is connected to both the first signal amplification module and the second signal amplification module and is used to obtain a noise signal power spectrum of an electronic device that eliminates the measurement noise signal.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic testing, and in particular to a signal measuring circuit and device. Background Art

[0002] As device sizes continue to shrink, the demands for device reliability and consistency continue to rise. Low-frequency noise, as an important measurement tool, can identify internal defects. Therefore, device noise testing and analysis has become a key indicator of device quality. Furthermore, device low-frequency noise characteristics are closely linked to reliability, making it a crucial indicator of device reliability.

[0003] However, as the size of devices under test continues to shrink, the device noise signal is also getting smaller and smaller, which puts higher and higher requirements on the measurement of noise signals, especially for the acquisition of extremely low-frequency noise signals. The system must be further optimized to improve test accuracy. Summary of the Invention

[0004] Based on this, it is necessary to provide a signal measurement circuit and device to improve the accuracy of noise measurement of tiny electronic components.

[0005] On one hand, the present application provides a signal measurement circuit for measuring a low-frequency noise signal emitted by an electronic device, the signal measurement circuit comprising a reference resistor network module, a first signal amplification module, a bias test module, a second signal amplification module, and a spectrum reconstruction module, wherein the reference resistor network module is used to generate a first reference noise signal and a second reference noise signal that are differential signals; the first signal amplification module is connected to the reference resistor network module and is used to generate a reference loop noise signal with a preset amplification factor based on the first reference noise signal and the second reference noise signal; the reference loop noise signal comprises a reference resistor network noise signal and a measurement noise signal; the bias test module is used to generate a noise signal to be measured and a reference noise signal that are differential signals. acoustic signal; the second signal amplification module is connected to the bias test module, and is used to generate a test loop noise signal with a preset amplification factor according to the noise signal to be measured and the reference noise signal; the test loop noise signal includes the bias test module noise signal and the measurement noise signal; the spectrum reconstruction module is connected to both the first signal amplification module and the second signal amplification module, and is used to obtain a reference loop noise signal power spectrum according to the reference loop noise signal, and obtain a test loop noise signal power spectrum according to the test loop noise signal, and obtain an electronic device noise signal power spectrum that eliminates the measurement noise signal according to the reference loop noise signal power spectrum, the test loop noise signal power spectrum and the reference resistor network noise signal power spectrum.

[0006] In the signal measurement circuit described in the above embodiment, two symmetrical noise measurement circuits are set up, namely a reference loop composed of a reference resistor network module and a first signal amplification module, and a test loop composed of a bias measurement module and a second signal amplification module. In the reference loop, the reference resistor network module selects relatively ideal resistor elements to keep the noise signal emitted by the reference resistor network module relatively stable, and amplifies the signal through the first signal amplification module to output a reference loop noise signal with a preset amplification factor. The signal includes the reference resistor network noise signal and the measurement noise signal. Therefore, by subtracting the measured reference loop noise signal from the reference resistor network noise signal, the noise signal of the measurement circuit system, that is, the measurement noise signal, can be obtained. Similarly, in the test loop, the test loop noise signal including the bias test module noise signal and the measurement noise signal can be finally obtained. Since the reference loop and the test loop are different, the noise signal of the measurement circuit system can be obtained. The two are symmetrically set up, and the measurement noise signals of the two are equal. By subtracting the test loop noise signal from the measurement noise signal, the bias test module noise signal, that is, the noise of the electronic device to be tested, can be obtained. On the one hand, the above-mentioned test system eliminates the common-mode noise in the test process through the first signal amplification module and the second signal amplification module, so that the front-end reference resistor network module and the bias test module eliminate the noise interference of the bias power supply on the measurement circuit, and obtain clean low-frequency noise signals of the electronic components to be tested and the ideal resistor. On the other hand, the reference loop can measure and obtain the noise interference signal generated by the power supply in the back-end amplification module, and then eliminate it in the test loop, and finally obtain a clean noise signal of the electronic component to be tested. The above-mentioned embodiment does not adopt the traditional method of shielding or weakening various interference noises, but allows the interference noise to exist and cleverly eliminates it through measurement and calculation, thereby achieving higher measurement accuracy.

[0007] In one embodiment, the reference resistor network module includes a first resistor, a second resistor, a third resistor and a fourth resistor; wherein the first resistor is configured as: the first end is connected to the power supply, and the second end is grounded through the second resistor; the third resistor is configured as: the first end is connected to the power supply, and the second end is grounded through the fourth resistor; wherein the reference resistor network module outputs the first reference noise signal through the second end of the first resistor; and the reference resistor network module outputs the second reference noise signal through the second end of the third resistor.

[0008] In one embodiment, the first signal amplification module includes a first differential amplifier and a first adjustable gain amplifier, wherein the first differential amplifier is used to generate a differentially amplified reference loop noise signal based on the first reference noise signal and the second reference noise signal, and the first differential amplifier is configured as follows: the positive input end is connected to the second end of the first resistor, and the negative input end is connected to the second end of the third resistor; the first adjustable gain amplifier is connected to the first differential amplifier, and is used to generate the reference loop noise signal with the preset amplification factor based on the differentially amplified reference loop noise signal.

[0009] In one embodiment, the bias test module includes a fifth resistor, a sixth resistor and a seventh resistor; wherein the fifth resistor is configured as follows: a first end is connected to a power supply, and a second end is grounded through the electronic device; the sixth resistor is configured as follows: a first end is connected to a power supply, and a second end is grounded through the seventh resistor; wherein the bias test module outputs the noise signal to be measured through the second end of the fifth resistor; and the bias test module outputs the reference noise signal through the second end of the sixth resistor.

[0010] In one embodiment, the second signal amplification module includes a second differential amplifier and a second adjustable gain amplifier, wherein the second differential amplifier is used to generate a differentially amplified test loop noise signal based on the noise signal to be measured and the reference noise signal, and the second differential amplifier is configured as follows: the positive input end is connected to the second end of the fifth resistor, and the negative input end is connected to the second end of the sixth resistor; the second adjustable gain amplifier is connected to the second differential amplifier, and is used to generate the test loop noise signal with the preset amplification factor based on the differentially amplified test loop noise signal.

[0011] In one embodiment, the resistance of the electronic device is equal to the resistance of the first resistor, the resistance of the second resistor, the resistance of the third resistor, the resistance of the fourth resistor, the resistance of the fifth resistor, the resistance of the sixth resistor, and the resistance of the seventh resistor.

[0012] In one embodiment, the amplification factor of the first differential amplifier is equal to the amplification factor of the second differential amplifier, and the amplification factor of the first adjustable gain amplifier is equal to the amplification factor of the second adjustable gain amplifier.

[0013] In one embodiment, the spectrum reconstruction module includes a first sampling unit, a second sampling unit and a spectrum reconstruction unit, wherein the first sampling unit is connected to the first adjustable gain amplifier, and is used to convert the reference loop noise analog signal into a reference loop noise digital signal; the second sampling unit is connected to the second adjustable gain amplifier, and is used to convert the test loop noise analog signal into a test loop noise digital signal; the spectrum reconstruction unit is connected to both the first sampling unit and the second sampling unit, and is used to obtain the reference loop noise signal power spectrum based on the reference loop noise digital signal, and obtain the test loop noise signal power spectrum based on the test loop noise digital signal, and obtain the electronic device noise signal power spectrum that eliminates the measurement noise signal based on the reference loop noise signal power spectrum, the test loop noise signal power spectrum and the reference resistor network noise signal power spectrum.

[0014] In one embodiment, the power spectrum F(ω) of the electronic device noise signal is calculated according to the following formula:

[0015]

[0016] Wherein, F(ω) is the power spectrum of the noise signal of the electronic device, R DUT is the resistance of the electronic device, R7 is the resistance of the seventh resistor, S t (ω) is the power spectrum of the test loop noise signal, S f (ω) is the power spectrum of the reference loop noise signal, S f-0 (ω) is the power spectrum of the reference resistor network noise signal.

[0017] A second aspect of the present application provides a signal measuring device, comprising the signal measuring circuit described in any one of the aforementioned embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 A schematic diagram of the structure of a signal measurement circuit in an embodiment provided in this application;

[0020] Figure 2 A circuit schematic diagram of a reference resistor network module and a bias test module in an embodiment provided in this application;

[0021] Figure 3This is a structural principle diagram of a signal measurement circuit in another embodiment provided by the present application. DETAILED DESCRIPTION

[0022] To facilitate understanding of the present application, the present application will be described more fully below with reference to the accompanying drawings. The accompanying drawings provide embodiments of the present application. However, the present application may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to make the disclosure of the present application more thorough and comprehensive.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application pertains. The terms used herein in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application.

[0024] It will be understood that the terms "first," "second," etc., used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish a first element from another element. For example, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor without departing from the scope of this application. The first resistor and the second resistor are both resistors, but they are not the same resistor.

[0025] It can be understood that the “connection” in the following embodiments should be understood as “electrical connection”, “communication connection”, etc. if there is transmission of electrical signals or data between the connected circuits, modules, units, etc.

[0026] As used herein, the singular forms "a," "an," and "the" may also include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include," "comprising," "having," and the like specify the presence of stated features, integers, steps, operations, components, parts, or combinations thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, components, parts, or combinations thereof. Furthermore, the term "and / or" as used in this specification includes any and all combinations of the relevant listed items.

[0027] As electronic components continue to shrink in size, their low-frequency noise performance is also declining, necessitating the design of improved low-frequency noise test systems. In particular, to measure lower-power noise signals, system optimization and increased sensitivity are essential. Current high-precision test systems typically utilize discrete components to build test system models, thereby reducing the system noise floor. These systems also employ circuit structure techniques to improve measurement accuracy. However, for the acquisition of extremely low-frequency noise signals, the noise characteristics over long periods require further optimization to enhance test accuracy.

[0028] Based on this, it is necessary to provide a signal measurement circuit and device to improve the accuracy of noise measurement of tiny electronic components.

[0029] In one embodiment of the present application, Figure 1 As shown, a signal measurement circuit is provided for measuring a low-frequency noise signal emitted by an electronic device. The signal measurement circuit includes a reference resistor network module 100, a first signal amplification module 200, a bias test module 300, a second signal amplification module 400, and a spectrum reconstruction module 500. The reference resistor network module 100 is used to generate a first reference noise signal and a second reference noise signal that are differential signals. The first signal amplification module 200 is connected to the reference resistor network module 100 and is used to generate a reference loop noise signal with a preset amplification factor based on the first reference noise signal and the second reference noise signal. The reference loop noise signal includes a reference resistor network noise signal and a measurement noise signal. The bias test module 300 is used to generate a first reference noise signal and a second reference noise signal that are differential signals. The test circuit comprises a noise signal to be measured and a reference noise signal; the second signal amplification module 400 is connected to the bias test module 300, and is used to generate a test loop noise signal with a preset amplification factor according to the noise signal to be measured and the reference noise signal; wherein the test loop noise signal includes the bias test module noise signal and the measurement noise signal; the spectrum reconstruction module 500 is connected to both the first signal amplification module 200 and the second signal amplification module 400, and is used to obtain a reference loop noise signal power spectrum according to the reference loop noise signal, and obtain a test loop noise signal power spectrum according to the test loop noise signal, and obtain an electronic device noise signal power spectrum that eliminates the measurement noise signal according to the reference loop noise signal power spectrum, the test loop noise signal power spectrum and the reference resistor network noise signal power spectrum.

[0030] In the signal measurement circuit described in the above embodiment, two symmetrical noise measurement circuits are provided, namely a reference loop composed of a reference resistor network module 100 and a first signal amplification module 200, and a test loop composed of a bias measurement module 300 and a second signal amplification module 400. In the reference loop, the reference resistor network module 100 selects relatively ideal resistor elements to keep the noise signal emitted by the reference resistor network module 100 relatively stable, and amplifies the signal through the first signal amplification module 200 to output a reference loop noise signal with a preset amplification factor. The signal includes the reference resistor network noise signal and the measurement noise signal. Therefore, by subtracting the measured reference loop noise signal from the reference resistor network noise signal, the noise signal of the measurement circuit system, that is, the measurement noise signal, can be obtained. Similarly, in the test loop, a test loop noise signal including the bias test module noise signal and the measurement noise signal can be finally obtained. Since the reference loop and The test loops are symmetrically arranged, and the measurement noise signals of the two are equal. By subtracting the test loop noise signal from the measurement noise signal, the bias test module noise signal, that is, the noise of the electronic device under test, can be obtained. On the one hand, the above-mentioned test circuit eliminates the common-mode noise in the test process through the first signal amplification module 200 and the second signal amplification module 400, so that the front-end reference resistance network module 100 and the bias test module 300 eliminate the noise interference of the bias power supply on the measurement circuit, and obtain clean low-frequency noise signals of the electronic components under test and the ideal resistor. On the other hand, the reference loop can measure and obtain the noise interference signal generated by the power supply in the back-end amplification module, and then eliminate it in the test loop, and finally obtain a clean noise signal of the electronic component under test. The above-mentioned embodiment does not adopt the traditional method of shielding or weakening various interference noises, but allows the interference noise to exist and cleverly eliminates it through measurement and calculation, thereby achieving higher measurement accuracy.

[0031] As an example, Figure 2 As shown in Figure (a), the reference resistor network module 100 includes a first resistor R1, a second resistor R2, a third resistor R3 and a fourth resistor R4; wherein the first resistor R1 is configured as follows: a first end is connected to a bias power supply, and a second end is grounded through the second resistor R2; the third resistor R3 is configured as follows: a first end is connected to a bias power supply, and a second end is grounded through the fourth resistor R4; wherein the reference resistor network module 100 outputs a first reference noise signal through the second end of the first resistor R1; and the reference resistor network module 100 outputs a second reference noise signal through the second end of the third resistor R3.

[0032] Specifically, the reference resistor network module 100 is used to generate two standard differential signals for monitoring the noise signal of the measurement circuit itself. Therefore, in order not to introduce additional noise, the reference resistor network module 100 needs to have idealized output characteristics to minimize the noise interference caused by the unbalanced configuration of the reference resistor network module 100. In some embodiments, the first resistor R1, the second resistor R2, the third resistor R3 and the fourth resistor R4 can all be metal film resistors. Metal film resistors have high precision, stable performance, simple and lightweight structure, and are widely used in the electronics industry with high precision requirements. They are an ideal choice for the resistor element in this embodiment, and the resistance value of each resistor should satisfy the formula In order to obtain a more ideal technical effect, the resistor elements configured in this embodiment satisfy R1=R2=R3=R4=R DUT , where R DUT is the resistance value of the electronic device to be tested.

[0033] As an example, Figure 2 As shown in Figure (b), the bias test module 300 includes a fifth resistor R5, a sixth resistor R6 and a seventh resistor R7; wherein the fifth resistor R5 is configured as follows: a first end is connected to the power supply, and a second end is grounded through the electronic device under test DUT; the sixth resistor R6 is configured as follows: a first end is connected to the power supply, and a second end is grounded through the seventh resistor R7; wherein the bias test module 300 outputs the noise signal to be tested through the second end of the fifth resistor R5; and the bias test module 300 outputs the reference noise signal through the second end of the sixth resistor R6.

[0034] Specifically, the same standard is adopted for selecting the resistor elements as in the reference resistor network module 100. In order to obtain a better technical effect, the fifth resistor R5, the sixth resistor R6 and the seventh resistor R7 are all metal film resistors, and the resistance value of each resistor satisfies R5=R6=R7=R DUT .

[0035] As an example, see Figure 3 As shown, the first signal amplification module 200 includes a first differential amplifier 210 and a first adjustable gain amplifier 220, wherein the first differential amplifier 210 is used to generate a differentially amplified reference loop noise signal based on the first reference noise signal and the second reference noise signal. The first differential amplifier 210 is configured as follows: the positive input terminal is connected to the second end of the first resistor R1, and the negative input terminal is connected to the second end of the third resistor R3; the first adjustable gain amplifier 220 is connected to the first differential amplifier 210, and is used to generate a reference loop noise signal with a preset amplification factor based on the differentially amplified reference loop noise signal.

[0036] Specifically, the first differential amplifier 210 differentially amplifies the first reference noise signal and the second reference noise signal emitted by the reference resistor network module 100. Simultaneously, it filters the common-mode noise signal generated by the reference resistor network module 100, thereby eliminating interference generated by the bias power supply. To further amplify the reference resistor network noise signal output by the first differential amplifier 210 so that it can be sampled and received by a subsequent circuit, in this embodiment, a first adjustable gain amplifier 220 is also configured. This amplifier can adjust the ratio of the output signal of the first differential amplifier 210 according to the requirements of the subsequent sampling circuit, so that the amplitude of the final output signal is adaptive to the requirements of the subsequent sampling circuit. Furthermore, both the first differential amplifier 210 and the first adjustable gain amplifier 220 are powered by an external power supply, which inevitably introduces an interfering noise signal, namely, a measurement noise signal. The measurement noise signal and the reference resistor network noise signal are both amplified at the same ratio by the first adjustable gain amplifier 220, and the output reference loop noise signal is equal to the sum of the measurement noise signal and the reference resistor network noise signal.

[0037] As an example, please refer to Figure 3 The second signal amplification module 400 includes a second differential amplifier 410 and a second adjustable gain amplifier 420, wherein the second differential amplifier 410 is used to generate a differentially amplified test loop noise signal based on the noise signal to be measured and the reference noise signal. The second differential amplifier 410 is configured as follows: the positive input end is connected to the second end of the fifth resistor R5, and the negative input end is connected to the second end of the sixth resistor R6; the second adjustable gain amplifier 420 is connected to the second differential amplifier 410, and is used to generate a test loop noise signal with a preset amplification factor based on the differentially amplified test loop noise signal.

[0038] Specifically, the second signal amplification module 400 and the first signal amplification module 200 adopt the same configuration, that is, the second differential amplifier 410 and the first differential amplifier 210 have the same circuit configuration, and the second adjustable gain amplifier 420 and the first adjustable gain amplifier 220 have the same circuit configuration, so that the amplification factor of the first differential amplifier 210 is equal to the amplification factor of the second differential amplifier 410, and the amplification factor of the first adjustable gain amplifier 220 is equal to the amplification factor of the second adjustable gain amplifier 420. Therefore, the test loop noise signal ultimately output by the second adjustable gain amplifier 420 has the same amplification factor as the reference loop noise signal output by the first adjustable gain amplifier 220, and is equal to the sum of the measurement noise signal and the bias test noise signal.

[0039] As an example, please refer to Figure 3The spectrum reconstruction module 500 includes a first sampling unit 510, a second sampling unit 520, and a spectrum reconstruction unit 530, wherein the first sampling unit 510 is connected to the first adjustable gain amplifier 220, and is used to convert the reference loop noise analog signal into a reference loop noise digital signal; the second sampling unit 520 is connected to the second adjustable gain amplifier 420, and is used to convert the test loop noise analog signal into a test loop noise digital signal; the spectrum reconstruction unit 530 is connected to both the first sampling unit 510 and the second sampling unit 520, and is used to obtain a reference loop noise signal power spectrum based on the reference loop noise digital signal, and obtain a test loop noise signal power spectrum based on the test loop noise digital signal, and obtain an electronic device noise signal power spectrum for eliminating the measurement noise signal based on the reference loop noise signal power spectrum, the test loop noise signal power spectrum, and the reference resistor network noise signal power spectrum.

[0040] Specifically, power spectrum is the abbreviation of power spectral density function, which is defined as the signal power within a unit frequency band. It shows how the signal power changes with power, that is, the distribution of signal power in the frequency domain. The power spectrum shows the relationship between signal power and power. The square of the amplitude of the Fourier transform of the power signal is usually used as a measure of signal power. In a time period T, the power spectrum expression of the power signal is Among them, F T (ω) is the Fourier transform of the power signal. In this embodiment, according to the calculation formula of the power spectrum density function, the power spectrum of the reference loop noise signal can be obtained as:

[0041]

[0042] Among them, S f (ω) is the power spectrum of the reference loop noise signal, V f is a function of the reference loop noise signal, FFT(V f ) is the Fourier transform of the reference loop noise signal, A1 is the product of the amplification factor of the first differential amplifier 210 and the amplification factor of the first adjustable gain amplifier 220;

[0043] Similarly, the test loop noise signal power spectrum S t (ω) is:

[0044]

[0045] Among them, S t (ω) is the power spectrum of the test loop noise signal, V t is the function of the test loop noise signal, FFT(V t) is the Fourier transform of the test loop noise signal, T is the time period, A2 is the product of the amplification factor of the second differential amplifier 410 and the amplification factor of the second adjustable gain amplifier 420, and A1=A2.

[0046] As an example, please refer to Figure 2 In Figure (a), the thermal noise of each resistor in the reference resistor network module is fixed and can usually be calculated using the following formula:

[0047] S V =4kTR;

[0048] Among them, S V is the power density of the resistor thermal noise, k is the Boltzmann constant, T is the temperature, and R is the resistance value.

[0049] It can be seen that the thermal noise of an ideal resistor is a linear function of the resistance value. In this embodiment, the resistance value of each resistor in the reference resistor network module is equal to the resistance value of the electronic device to be tested. Therefore, the power spectrum of the reference resistor network noise signal is only related to the resistance value of the electronic device to be tested and is a certain value, expressed as S f-0 (ω) represents that, according to the analysis in the above embodiment, in the reference loop, the measurement noise signal is equal to the difference between the reference loop noise signal and the reference resistor network noise signal. Therefore, the measurement noise signal power spectrum can be expressed as:

[0050] S noise (ω)=S f (ω)-S f-0 (ω);

[0051] Among them, S noise (ω) is the power spectrum of the measurement noise signal.

[0052] As an example, please refer to Figure 2 In Figure (b), ignoring the thermal noise of the fifth resistor R5 and the sixth resistor R6, the noise signal power spectrum of the electronic device under test DUT and the seventh resistor R7 based on the resistor voltage divider principle can be obtained as follows:

[0053]

[0054] Among them, S DUT (ω) is the noise signal power spectrum of the electronic device under test (DUT). According to the explanation in the above embodiment, the noise signal is amplified by the second signal amplification module 400, thereby introducing a measurement noise signal. The measurement noise signal needs to be excluded. Therefore, the actual noise signal power spectrum of the electronic device under test can be obtained as follows:

[0055] F(ω)=S DUT (ω)-S noise(ω);

[0056] Where F(ω) is the power spectrum of the electronic device noise signal.

[0057] Substituting the formula in the above embodiment into the above formula, the final electronic device noise signal power spectrum F(ω) can be obtained as follows:

[0058]

[0059] A second aspect of the present application provides a signal measuring device, comprising the signal measuring circuit in any one of the aforementioned embodiments.

[0060] Throughout this specification, references to terms such as "some embodiments," "other embodiments," and "desired embodiments" indicate that a particular feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. Although these terms are used interchangeably throughout this specification, they do not necessarily refer to the same embodiment or example.

[0061] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0062] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A signal measurement circuit, characterized in that: Used to measure low-frequency noise signals emitted by electronic devices, the signal measurement circuit includes: A reference resistor network module, configured to generate a first reference noise signal and a second reference noise signal which are differential signals; a first signal amplification module, connected to the reference resistor network module, configured to generate a reference loop noise signal with a preset amplification factor based on the first reference noise signal and the second reference noise signal; the reference loop noise signal includes a reference resistor network noise signal and a measurement noise signal; A bias test module, used to generate a noise signal to be tested and a reference noise signal that are differential signals; a second signal amplification module, connected to the bias test module, for generating a test loop noise signal with a preset amplification factor according to the noise signal to be measured and the reference noise signal; the test loop noise signal includes the bias test module noise signal and the measurement noise signal; a spectrum reconstruction module connected to both the first signal amplification module and the second signal amplification module, configured to obtain a reference loop noise signal power spectrum based on the reference loop noise signal, obtain a test loop noise signal power spectrum based on the test loop noise signal, and obtain an electronic device noise signal power spectrum that eliminates the measurement noise signal based on the reference loop noise signal power spectrum, the test loop noise signal power spectrum, and the reference resistor network noise signal power spectrum.

2. The signal measurement circuit according to claim 1, characterized in that: The reference resistor network module includes a first resistor, a second resistor, a third resistor and a fourth resistor; The first resistor is configured such that: a first end is connected to a power supply, and a second end is grounded via the second resistor; The third resistor is configured as follows: a first end is connected to the power supply, and a second end is grounded through the fourth resistor; Wherein, the reference resistor network module outputs the first reference noise signal through the second end of the first resistor; The reference resistor network module outputs the second reference noise signal through the second end of the third resistor.

3. The signal measurement circuit according to claim 2, characterized in that: The first signal amplification module includes: a first differential amplifier, configured to generate a differentially amplified reference loop noise signal based on the first reference noise signal and the second reference noise signal, and configured such that: a positive input terminal is connected to the second end of the first resistor, and a negative input terminal is connected to the second end of the third resistor; The first adjustable gain amplifier is connected to the first differential amplifier and is used to generate the reference loop noise signal with the preset amplification factor according to the differentially amplified reference loop noise signal.

4. The signal measurement circuit according to claim 3, characterized in that: The bias test module includes a fifth resistor, a sixth resistor and a seventh resistor; The fifth resistor is configured such that: a first end is connected to a power supply, and a second end is grounded through the electronic device; The sixth resistor is configured as follows: a first end is connected to a power supply, and a second end is grounded via the seventh resistor; Wherein, the bias test module outputs the noise signal to be tested through the second end of the fifth resistor; The bias testing module outputs the reference noise signal through the second end of the sixth resistor.

5. The signal measurement circuit according to claim 4, characterized in that: The second signal amplification module includes: a second differential amplifier, configured to generate a differentially amplified test loop noise signal according to the noise signal to be measured and the reference noise signal, and configured such that: a positive input terminal is connected to the second end of the fifth resistor, and a negative input terminal is connected to the second end of the sixth resistor; The second adjustable gain amplifier is connected to the second differential amplifier and is used to generate the test loop noise signal with the preset amplification factor according to the differentially amplified test loop noise signal.

6. The signal measurement circuit according to claim 4 or 5, characterized in that: The resistance of the electronic device is equal to the resistance of the first resistor, the resistance of the second resistor, the resistance of the third resistor, the resistance of the fourth resistor, the resistance of the fifth resistor, the resistance of the sixth resistor, and the resistance of the seventh resistor.

7. The signal measurement circuit according to claim 5, characterized in that: The amplification factor of the first differential amplifier is equal to the amplification factor of the second differential amplifier, and the amplification factor of the first adjustable gain amplifier is equal to the amplification factor of the second adjustable gain amplifier.

8. The signal measurement circuit according to claim 7, characterized in that: The spectrum reconstruction module includes: a first sampling unit connected to the first adjustable gain amplifier, configured to convert a reference loop noise analog signal into a reference loop noise digital signal; a second sampling unit, connected to the second adjustable gain amplifier, and configured to convert the test loop noise analog signal into a test loop noise digital signal; a spectrum reconstruction unit connected to both the first sampling unit and the second sampling unit, configured to obtain a power spectrum of the reference loop noise signal based on the reference loop noise digital signal, obtain a power spectrum of the test loop noise signal based on the test loop noise digital signal, and obtain a power spectrum of the electronic device noise signal that eliminates the measurement noise signal based on the reference loop noise signal power spectrum, the test loop noise signal power spectrum, and the reference resistor network noise signal power spectrum.

9. The signal measurement circuit according to claim 8, characterized in that: The power spectrum F(ω) of the electronic device noise signal is calculated according to the following formula: Wherein, F(ω) is the power spectrum of the noise signal of the electronic device, R DUT is the resistance of the electronic device, R7 is the resistance of the seventh resistor, S t (ω) is the power spectrum of the test loop noise signal, S f (ω) is the power spectrum of the reference loop noise signal, S f-0 (ω) is the power spectrum of the reference resistor network noise signal.

10. A signal measuring device, characterized in that: The method comprises the signal measuring circuit according to any one of claims 1 to 9.

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