CN115664419A

CN115664419A - Signal conditioning circuit and measuring device

Info

Publication number: CN115664419A
Application number: CN202211257754.6A
Authority: CN
Inventors: 胡俊
Original assignee: Hubei Eve Power Co Ltd
Current assignee: Hubei Eve Power Co Ltd
Priority date: 2022-10-13
Filing date: 2022-10-13
Publication date: 2023-01-31

Abstract

The circuit outputs a first conduction signal when the voltage value of an input voltage signal is smaller than the threshold value of a voltage threshold signal through a selection circuit, and then a first subsection voltage conditioning sub-circuit conditions the input voltage signal according to the received first conduction signal and outputs a first output voltage signal; when the voltage value of the input voltage signal is larger than the threshold value of the voltage threshold signal, the selection circuit outputs a second conduction signal, the second segmented voltage conditioning sub-circuit conditions the input voltage signal and outputs a second output voltage signal, high-precision wide-range voltage signal conditioning is realized, the applicable sampling range of voltage sampling conditioning is increased aiming at different gain modes of voltage sampling of different segments, the sampling precision and the universality are improved, the applicable scene of voltage sampling conditioning is widened, the universality of the circuit and the accuracy of sampling conditioning are improved, and the circuit cost is reduced.

Description

Signal conditioning circuit and measuring device

Technical Field

The present application relates to the field of signal conditioning technologies, and in particular, to a signal conditioning circuit and a measurement device.

Background

Signal conditioning circuitry is circuitry that converts analog signals into digital signals that can be used for data acquisition, control of processes, performing calculations, display readout, and the like. Sampling and conditioning of voltage signals are the main components in the signal conditioning circuit.

In the actual voltage sampling process, the input voltage range is very wide. When the input voltage is larger, the range of the sampling circuit is exceeded; when the input voltage is too small, the sampling precision is insufficient or the sampling is not available. Usually, a fixed amplification factor is adopted to amplify and sample the input voltage, the sampling precision is low, and the voltage continuity conditioning cannot be carried out. If the microcontroller is adopted to control the segmented sampling, the circuit is complex and the cost is high.

Disclosure of Invention

Therefore, it is necessary to provide a signal conditioning circuit and a measuring device, which can increase the applicable sampling range of voltage sampling conditioning, realize segmented voltage continuous conditioning, improve the sampling precision, and widen the applicable scenes of the voltage sampling circuit, in order to solve the problems existing in the existing voltage sampling conditioning method.

In a first aspect, the present application provides a signal conditioning circuit comprising:

a voltage threshold circuit configured to output a voltage threshold signal;

the segmented voltage conditioning circuit comprises a first segmented voltage conditioning sub-circuit and a second segmented voltage conditioning sub-circuit; the first segmented voltage conditioning sub-circuit is configured to condition an input voltage signal according to a received first conducting signal and output a first output voltage signal; the second segmented voltage conditioning sub-circuit is configured to condition the input voltage signal according to the received second conducting signal and output a second output voltage signal;

the selection circuit is respectively connected with the voltage threshold circuit, the first segmented voltage conditioning sub-circuit and the second segmented voltage conditioning sub-circuit; the selection circuit is configured to receive an input voltage signal and a voltage threshold signal; the selection circuit is further configured to output a first conduction signal when the voltage value of the input voltage signal is less than a threshold value of the voltage threshold signal, and output a second conduction signal when the voltage value of the input voltage signal is greater than the threshold value of the voltage threshold signal.

Optionally, the selection circuit comprises a first comparator and a second comparator;

the first input end of the first comparator is used for receiving an input voltage signal, the second input end of the first comparator is connected with the output end of the voltage threshold circuit, and the output end of the first comparator is connected with the first segmented voltage conditioning sub-circuit; the power supply end of the voltage threshold circuit is used for connecting a direct-current power supply;

the first input end of the second comparator is connected with the output end of the voltage threshold circuit, the second input end of the second comparator is used for receiving an input voltage signal, and the output end of the second comparator is connected with the second segmented voltage conditioning sub-circuit.

Optionally, the voltage threshold circuit includes a first resistor and a second resistor;

the first end of the first resistor is connected with the direct-current power supply, the second end of the first resistor is connected with the first end of the second resistor, the second end of the second resistor is connected with the ground wire, and the second input end of the first comparator and the first input end of the second comparator are respectively connected between the second end of the first resistor and the first end of the second resistor.

Optionally, the first segmented voltage conditioning sub-circuit includes a first switching tube and a first proportional operational amplifier sub-circuit;

the grid electrode of the first switch tube is connected with the output end of the first comparator, and the drain electrode of the first switch tube is used for accessing an input voltage signal; the source electrode of the first switching tube is connected with the non-inverting input end of the first proportional operational amplification sub-circuit, and the output end of the first proportional operational amplification sub-circuit is configured to output a first proportional amplification voltage signal.

Optionally, the second segmented voltage conditioning sub-circuit includes a second switching tube, a second proportional operational amplifier sub-circuit, a first differential amplifier sub-circuit, and a continuous output adjusting circuit;

the grid electrode of the second switching tube is connected with the output end of the second comparator, and the drain electrode of the second switching tube is used for accessing an input voltage signal; the source electrode of the second switch tube is connected with the non-inverting input end of the second proportional operational amplification sub-circuit, the output end of the second proportional operational amplification sub-circuit is configured to transmit a second proportional amplification voltage signal to the non-inverting input end of the first differential amplification sub-circuit, and the inverting input end of the first differential amplification sub-circuit is connected with the continuous output regulating circuit; the output of the first differential amplification sub-circuit is configured to output a regulated second scaled amplified voltage signal.

Optionally, the first segment voltage conditioning sub-circuit further includes a first voltage follower sub-circuit;

the non-inverting input end of the first voltage follower sub-circuit is connected with the output end of the first proportional operational amplifier sub-circuit.

Optionally, the second segment voltage conditioning sub-circuit further includes a second voltage follower sub-circuit;

the non-inverting input end of the second voltage following sub-circuit is connected with the output end of the first differential amplification sub-circuit.

Optionally, the continuous output adjusting circuit includes a third resistor and a fourth resistor;

the first end of the third resistor is connected with the direct-current power supply, the second end of the third resistor is connected with the first end of the fourth resistor, the second end of the fourth resistor is connected with the ground wire, and the inverting input end of the first differential amplification sub-circuit is connected between the second end of the third resistor and the first end of the fourth resistor.

Optionally, the first comparator is an operation comparator; the second comparator is an operational comparator.

In a second aspect, the present application provides a signal measurement device comprising a signal conditioning circuit as claimed in any one of the preceding claims.

One of the above technical solutions has the following advantages and beneficial effects:

the signal conditioning circuit comprises a voltage threshold circuit, a segmented voltage conditioning circuit and a selection circuit; the segmented voltage conditioning circuit comprises a first segmented voltage conditioning sub-circuit and a second segmented voltage conditioning sub-circuit; configured to output a voltage threshold signal via a voltage threshold circuit; the selection circuit is respectively connected with the voltage threshold circuit, the first segmented voltage conditioning sub-circuit and the second segmented voltage conditioning sub-circuit; the selection circuit is configured to receive an input voltage signal and a voltage threshold signal; the selection circuit is further configured to output a first conduction signal when the voltage value of the input voltage signal is smaller than the threshold value of the voltage threshold signal, and the first segmented voltage conditioning sub-circuit conditions the input voltage signal according to the received first conduction signal and outputs a first output voltage signal; when the voltage value of the input voltage signal is larger than the threshold value of the voltage threshold signal, the selection circuit outputs a second conduction signal, and then the second segmented voltage conditioning sub-circuit conditions the input voltage signal according to the received second conduction signal, outputs a second output voltage signal, and achieves high-precision and wide-range voltage signal conditioning. According to the voltage signal conditioning method and device, voltage signal conditioning is optimally designed, flexibility is improved by automatically conditioning the voltage in a segmented mode, and the segmented voltage conditioning circuit is designed and is respectively connected with the voltage threshold circuit, the first segmented voltage conditioning sub-circuit and the second segmented voltage conditioning sub-circuit on the basis of the selection circuit, so that segmented voltage continuous conditioning is achieved; aiming at different gain modes of voltage sampling of different sections, the applicable sampling range of voltage sampling conditioning is increased, and the sampling precision and the universality are improved, so that the applicable scenes of voltage sampling conditioning are widened, the universality of the circuit and the accuracy of sampling conditioning are improved, and the circuit cost is reduced.

Drawings

Fig. 1 is a schematic diagram of a first circuit structure of a signal conditioning circuit according to an embodiment of the present disclosure.

Fig. 2 is a schematic diagram of a second circuit structure of a signal conditioning circuit according to an embodiment of the present disclosure.

Fig. 3 is a schematic diagram of a third circuit structure of a signal conditioning circuit according to an embodiment of the present disclosure.

Fig. 4 is a schematic diagram of a fourth circuit structure of the signal conditioning circuit in the embodiment of the present application.

Fig. 5 is a schematic diagram of a fifth circuit structure of a signal conditioning circuit according to an embodiment of the present application.

Fig. 6 is a schematic diagram of a sixth circuit structure of a signal conditioning circuit according to an embodiment of the present application.

Reference numerals:

a voltage threshold circuit 100; a segmented voltage conditioning circuit 200; a first segment voltage conditioning subcircuit 210; a first proportional operational amplifier sub-circuit 212; a first voltage follower sub-circuit 214; a second segmented voltage conditioning sub-circuit 220; a second proportional operational amplifier sub-circuit 222; a first differential amplification sub-circuit 224; a continuous output adjustment circuit 226; a second voltage follower sub-circuit 228; a selection circuit 300; a first comparator B1; a second comparator B2; a first switching tube Q1; a second switching tube Q2; a first resistor R1; a second resistor R2; a third resistor R3; a fourth resistor R4; a fifth resistor R5; a sixth resistor R6; a seventh resistor R7; an eighth resistor R8; a ninth resistor R9; a tenth resistor R10; an eleventh resistor R11; and a twelfth resistor R12.

Detailed Description

In order to make the technical solutions better understood by those skilled in the art, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only partial embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

It should be noted that the terms "first," "second," and the like in the description and claims of this application and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It should be understood that the data so used may be interchanged under appropriate circumstances such that embodiments of the application described herein may be used. 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.

In addition, the term "plurality" shall mean two as well as more than two.

The voltage sampling and conditioning method aims to solve the problems existing in the existing voltage sampling and conditioning mode. In one embodiment, as shown in fig. 1, a signal conditioning circuit is provided that includes a voltage threshold circuit 100, a segmented voltage conditioning circuit 200, and a selection circuit 300.

The voltage threshold circuit 100 is configured to output a voltage threshold signal; the segmented voltage conditioning circuit 200 includes a first segmented voltage conditioning sub-circuit 210 and a second segmented voltage conditioning sub-circuit 220; the first segment voltage conditioning sub-circuit 210 is configured to condition the input voltage signal according to the received first turn-on signal, and output a first output voltage signal; the second segment voltage conditioning sub-circuit 220 is configured to condition the input voltage signal according to the received second conducting signal and output a second output voltage signal; the selection circuit 300 is respectively connected with the voltage threshold circuit 100, the first segment voltage conditioning sub-circuit 210 and the second segment voltage conditioning sub-circuit 220; the selection circuit 300 is configured to receive an input voltage signal and a voltage threshold signal; the selection circuit 300 is further configured to output a first turn-on signal when the voltage value of the input voltage signal is smaller than the threshold value of the voltage threshold signal, and output a second turn-on signal when the voltage value of the input voltage signal is larger than the threshold value of the voltage threshold signal.

The voltage threshold circuit 100 is connected to the selection circuit 300, and the voltage threshold circuit 100 can output the voltage threshold signal to the selection circuit 300 by configuring a resistance value to the voltage threshold circuit 100. The threshold value of the first voltage threshold signal refers to a corresponding voltage threshold value. Segmented voltage conditioning circuit 200 may include 2 respective sub-circuits. For example, the segmented voltage conditioning circuit 200200 may include a first segmented voltage conditioning sub-circuit 210 and a second segmented voltage conditioning sub-circuit 220. The first segment voltage conditioning sub-circuit 210 may perform signal conditioning on the input voltage signal based on a first preset amplification ratio, and further output a first output voltage signal; the second segment voltage conditioning sub-circuit 220 may perform signal conditioning on the input voltage signal based on a second preset amplification ratio, and further output a second output voltage signal.

The selection circuit 300 may be provided with an input interface for receiving an input voltage signal. Based on that the selection circuit 300 is connected to the voltage threshold circuit 100, the selection circuit 300 can receive the input voltage signal and the voltage threshold signal, compare the input voltage signal with the voltage threshold signal, and according to the comparison result, output the first conducting signal to the first segment voltage conditioning sub-circuit 210 when the voltage value of the input voltage signal is smaller than the threshold value of the voltage threshold signal, so that the first segment voltage conditioning sub-circuit 210 conditions the input voltage signal according to the received first conducting signal and outputs the first output voltage signal. The selection circuit 300300 outputs a second conducting signal when the voltage value of the input voltage signal is greater than the threshold value of the voltage threshold signal, so that the second segment voltage conditioning sub-circuit 220 conditions the input voltage signal according to the received second conducting signal and outputs a second output voltage signal. And the voltage signal conditioning of the two-section voltage range of the input voltage signal is realized based on the signal conditioning channel of the set section voltage range.

In the above embodiment, the voltage threshold circuit 100, the segmented voltage conditioning circuit 200 and the selection circuit 300 are set; the segmented voltage conditioning circuit 200 is arranged into 2 paths (a first segmented voltage conditioning subcircuit 210 and a second segmented voltage conditioning subcircuit 220), and through optimized design of voltage signal conditioning, the voltage is automatically and segmentally conditioned, so that the flexibility is increased, and further segmented voltage continuous conditioning is realized; aiming at different gain modes of voltage sampling of different sections, the applicable sampling range of voltage sampling conditioning is increased, and the sampling precision and the universality are improved, so that the applicable scenes of voltage sampling conditioning are widened, the universality of the circuit and the accuracy of sampling conditioning are improved, and the circuit cost is reduced.

In one example, as shown in fig. 2, the selection circuit 300 includes a first comparator B1 and a second comparator B2.

A first input end of the first comparator B1 is configured to receive an input voltage signal, a second input end of the first comparator B1 is connected to the output end of the voltage threshold circuit 100, and an output end of the first comparator B1 is connected to the first segment voltage conditioning sub-circuit 210; the power supply terminal of the voltage threshold circuit 100 is connected to a dc power supply. A first input terminal of the second comparator B2 is connected to the output terminal of the voltage threshold circuit 100, a second input terminal of the second comparator B2 is configured to receive the input voltage signal, and an output terminal of the second comparator B2 is connected to the second segment voltage conditioning sub-circuit 220.

The first comparator B1 and the second comparator B2 may both adopt operation comparators.

For example, the first comparator B1 and the second comparator B2 are described by taking an operational comparator as an example. The first input of the first comparator B1 is referred to as the inverting input of the first comparator B1, and the second input of the first comparator B1 is referred to as the non-inverting input of the first comparator B1. The first input of the second comparator B2 refers to the inverting input of the second comparator B2 and the second input of the second comparator B2 refers to the non-inverting input of the second comparator B2.

The power source terminal based on the voltage threshold circuit 100 is connected to the dc power source, and the voltage threshold circuit 100 divides the voltage of the dc power source to output a voltage threshold signal. Based on that the first input end of the first comparator B1 receives the input voltage signal, the second input end of the first comparator B1 receives the voltage threshold signal, the first comparator B1 performs a voltage amplitude comparison between the input voltage signal and the first voltage threshold signal, and when the voltage amplitude of the input voltage signal is greater than the voltage amplitude of the voltage threshold signal, the first segmented voltage conditioning sub-circuit 210 maintains the off state; when the voltage amplitude of the input voltage signal is smaller than the voltage amplitude of the voltage threshold signal, the first conduction signal is transmitted to the first segment voltage conditioning sub-circuit 210, and then the first segment voltage conditioning sub-circuit 210 conditions the input voltage signal according to the received first conduction signal and outputs a first output voltage signal. Illustratively, the first turn-on signal may be a high level signal. For example, when the voltage amplitude of the input voltage signal is greater than the voltage amplitude of the voltage threshold signal, the first comparator B1 transmits a low level signal to the first segment voltage conditioning sub-circuit 210, and the first segment voltage conditioning sub-circuit 210 keeps an off state; when the voltage amplitude of the input voltage signal is smaller than the voltage amplitude of the voltage threshold signal, a high level signal is transmitted to the first segment voltage conditioning sub-circuit 210, and the first segment voltage conditioning sub-circuit 210 is turned on to operate.

Based on the first input terminal of the second comparator B2 receiving the voltage threshold signal, the second input terminal of the second comparator B2 receiving the input voltage signal, the second comparator B2 performing a voltage amplitude comparison between the input voltage signal and the voltage threshold signal, when the voltage amplitude of the input voltage signal is smaller than the voltage amplitude of the voltage threshold signal, the second segment voltage conditioning sub-circuit 220 keeps the off state; when the voltage amplitude of the input voltage signal is greater than the voltage amplitude of the voltage threshold signal, a second conduction signal is transmitted to the second segment voltage conditioning sub-circuit 220, and the second segment voltage conditioning sub-circuit 220 conditions the input voltage signal according to the received second conduction signal and outputs a second output voltage signal. Illustratively, the second turn-on signal may be a high level signal. For example, when the voltage amplitude of the input voltage signal is smaller than the voltage amplitude of the voltage threshold signal, the second comparator B2 transmits a low level signal to the second segment voltage conditioning sub-circuit 220, and the second segment voltage conditioning sub-circuit 220 maintains the off state; when the voltage amplitude of the input voltage signal is greater than the voltage amplitude of the voltage threshold signal, a high level signal is transmitted to the second segmented voltage conditioning sub-circuit 220, and the second segmented voltage conditioning sub-circuit 220 is turned on to operate.

In the above embodiment, by setting the voltage threshold circuit 100, the segmented voltage conditioning circuit 200, and the selection circuit 300, the selection circuit 300 includes the first comparator B1 and the second comparator B2, and by dividing 2 input voltage ranges, compares the input voltage signals, and when the voltage amplitude of the input voltage signal falls into the corresponding input voltage range, turns on the corresponding voltage conditioning sub-circuit (the first voltage conditioning sub-circuit and the second voltage conditioning sub-circuit), thereby implementing high-precision wide-range voltage signal conditioning. According to the voltage signal conditioning method and device, voltage signal conditioning is optimally designed, voltage is automatically and sectionally conditioned, flexibility is improved, and continuous conditioning of the sectionally-voltage is achieved; aiming at different gain modes of voltage sampling of different sections, the applicable sampling range of voltage sampling conditioning is increased, and the sampling precision and the universality are improved, so that the applicable scenes of voltage sampling conditioning are widened, the universality of the circuit and the accuracy of sampling conditioning are improved, and the circuit cost is reduced.

In one example, as shown in fig. 3, the voltage threshold circuit 100 includes a first resistor R1 and a second resistor R2. The first end of the first resistor R1 is connected with a direct current power supply, the second end of the first resistor R1 is connected with the first end of the second resistor R2, the second end of the second resistor R2 is connected with a ground wire, and the second input end of the first comparator B1 and the first input end of the second comparator B2 are respectively connected between the second end of the first resistor R1 and the first end of the second resistor R2.

Based on the connection relationship between the first resistor R1 and the second resistor R2, if the resistance of the first resistor R1 is R1, the resistance of the second resistor R2 is R2, and the voltage value of the dc power supply is vcc, the voltage threshold value of the voltage threshold signal of the voltage threshold circuit 100 is set to be R1, R2, and vcc

For example, the first resistor R1 and the second resistor R2 may be adjustable resistors.

Based on the voltage threshold setting of the voltage threshold circuit 100, the detection range of the input Voltage (VIN) can be further divided into the following 2 sections: the first section is VIN < VTH1; the second stage is VIN > VTH1.

In one example, as shown in fig. 4, the first segmented voltage conditioning sub-circuit 210 includes a first switching tube Q1 and a first proportional operational amplifier sub-circuit 212. The grid electrode of the first switching tube Q1 is connected with the output end of the first comparator B1, and the drain electrode of the first switching tube Q1 is used for accessing an input voltage signal; the source of the first switch Q1 is connected to the non-inverting input terminal of the first proportional operational amplifier sub-circuit 212, and the output terminal of the first proportional operational amplifier sub-circuit 212 is configured to output a first proportional amplified voltage signal.

The first scaling sub-circuit 212 is configured to perform a first predetermined scaling process on the input voltage signal. The first switching tube Q1 may be a MOS tube, for example, the first switching tube Q1 may be an N-type MOS tube.

When the voltage amplitude VIN of the input voltage signal is smaller than the voltage threshold VTH1 of the voltage threshold signal, the first comparator B1 outputs a high level signal (i.e., a first conduction signal), and the gate of the first switch Q1 receives the first conduction signal, so that the first switch Q1 is turned on; the drain electrode based on the first switch tube Q1 is used for accessing an input voltage signal; the source of the first switch Q1 is connected to the non-inverting input terminal of the first scaling sub-circuit 212, and the non-inverting input terminal of the first scaling sub-circuit 212 receives the input voltage signal, and outputs the first scaled voltage signal through the first predetermined scaling process of the first scaling sub-circuit 212.

In one example, as shown in fig. 4, the second segmented voltage conditioning sub-circuit 220 includes a second switching tube Q2, a second proportional operational amplification sub-circuit 222, a first differential amplification sub-circuit 224, and a continuous output regulation circuit 226. The grid electrode of the second switch tube Q2 is connected with the output end of the second comparator B2, and the drain electrode of the second switch tube Q2 is used for accessing an input voltage signal; the source of the second switch Q2 is connected to the non-inverting input terminal of the second proportional operational amplifier sub-circuit 222, the output terminal of the second proportional operational amplifier sub-circuit 222 is configured to transmit the second proportional amplified voltage signal to the non-inverting input terminal of the first differential amplifier sub-circuit 224, and the inverting input terminal of the first differential amplifier sub-circuit 224 is connected to the continuous output adjusting circuit 226; the output of the first differential amplification sub-circuit 224 is configured to output a regulated second scaled amplified voltage signal.

The second scaling sub-circuit 222 is configured to perform a second predetermined scaling process on the input voltage signal. The first differential amplifier sub-circuit 224 has the characteristic of circuit symmetry, and can play a role in stabilizing the operating point. The continuous output adjust circuit 226 is used to adjust the output voltage such that the output voltage has continuity. For example, the continuous output adjust circuit 226 is configured to output a first continuous output adjust signal.

When the voltage amplitude VIN of the input voltage signal is greater than the voltage threshold VTH1 of the voltage threshold signal, the second comparator B2 outputs a high level signal (i.e., a second conduction signal), and the gate of the second switching tube Q2 receives the second conduction signal, so that the second switching tube Q2 is turned on; the drain electrode of the second switching tube Q2 is used for accessing an input voltage signal; the source of the second switch Q2 is connected to the non-inverting input terminal of the second scaling sub-circuit 222, and the non-inverting input terminal of the second scaling sub-circuit 222 receives the input voltage signal, and the second scaled voltage signal is transmitted to the non-inverting input terminal of the first differential amplifier sub-circuit 224 through the second predetermined scaling amplification of the second scaling sub-circuit 222. Based on that the inverting input terminal of the first differential amplification sub-circuit 224 is connected to the continuous output adjustment circuit 226, the inverting input terminal of the first differential amplification sub-circuit 224 is connected to the first continuous output adjustment signal, and the output terminal of the first differential amplification sub-circuit 224 outputs the adjusted second proportional amplification voltage signal through the differential amplification processing of the first differential amplification sub-circuit 224.

By optimally designing voltage signal conditioning, automatically conditioning the input voltage in sections, sampling different gain modes for different voltage sections, increasing the applicable sampling range of voltage sampling conditioning, improving the sampling precision and universality and reducing the circuit cost. By arranging the continuous output regulating circuit 226, the voltage output continuity is realized, the application scene of voltage sampling conditioning is widened, and the universality of the circuit and the accuracy of sampling conditioning are improved.

In one example, as shown in fig. 5, the first segment voltage conditioning subcircuit 210 further includes a first voltage follower subcircuit 214. The non-inverting input terminal of the first voltage follower sub-circuit 214 is connected to the output terminal of the first scaling amplifier sub-circuit 212.

Based on the non-inverting input terminal of the first voltage follower sub-circuit 214 being connected to the output terminal of the first scaling sub-circuit 212, the first voltage follower sub-circuit 214 plays a role in buffering and isolation, so that the first scaling sub-circuit 212 and the back-end circuit are not affected by each other, and the reliability of voltage signal conditioning is improved.

In one example, as shown in fig. 5, the second segmented voltage conditioning subcircuit 220 further includes a second voltage follower subcircuit 228. The non-inverting input of the second voltage follower sub-circuit 228 is connected to the output of the first differential amplifier sub-circuit 224.

Based on the non-inverting input terminal of the second voltage follower sub-circuit 228 being connected to the output terminal of the first differential amplifier sub-circuit 224, the first voltage follower sub-circuit 214 plays a role in buffering and isolating, so that the first differential amplifier sub-circuit 224 and the back-end circuit are not affected by each other, and the reliability of voltage signal conditioning is improved.

In one example, as shown in fig. 6, the continuous output adjustment circuit 226 includes a third resistor R3 and a fourth resistor R4. The first end of the third resistor R3 is connected to the dc power supply, the second end of the third resistor R3 is connected to the first end of the fourth resistor R4, the second end of the fourth resistor R4 is connected to the ground, and the inverting input terminal of the first differential amplifier sub-circuit 224 is connected between the second end of the third resistor R3 and the first end of the fourth resistor R4.

Based on the above connection relationship between the third resistor R3 and the fourth resistor R4, if the resistance of the third resistor R3 is R3, the resistance of the fourth resistor R4 is R4, and the voltage value of the dc power supply VCC is VCC, the voltage regulation value of the first continuous output regulation signal of the continuous output regulation circuit 226 is:

illustratively, the third resistor R3 and the fourth resistor R4 may be adjustable resistors.

In one example, as shown in fig. 6, the voltage threshold sub-circuit includes a first resistor R1 and a second resistor R2. The resistance of the first resistor R1 is R1, the resistance of the second resistor R2 is R2, the resistance of the third resistor R3 is R3, the resistance of the fourth resistor R4 is R4, and the voltage of the direct current power supply VCC is VCC.

Through setting up the resistance R1 of first resistance R1, the resistance R2 of second resistance R2, and then set up the voltage threshold value VTH1 of first voltage threshold signal and be:

the input voltage VIN is compared with a voltage threshold VTH1 of the first voltage threshold signal through the selection circuit 300, when VIN is smaller than VTH1, the first switching tube Q1 of the first segment voltage conditioning sub-circuit 210 is closed, the second switching tube Q2 is opened, the first segment voltage conditioning sub-circuit 210 is turned on and works, and the second segment voltage conditioning sub-circuit 220 is opened and does not work; when VTH1 is less than VIN, the second switch Q2 of the first segment voltage conditioning sub-circuit 210 is turned on, and the first switch Q1 is turned off, so that the second segment voltage conditioning sub-circuit 220 is turned on and operated, and the first segment voltage conditioning sub-circuit 210 is turned off and does not operate.

Specifically, as shown in fig. 6, the first proportional operational amplifier sub-circuit 212 includes a first operational amplifier, a fifth resistor R5 (having a resistance value R5), and a sixth resistor R6 (having a resistance value R6); the second proportional operational amplifier sub-circuit 222 includes a second operational amplifier, a seventh resistor R7 (with a resistance value R7), and an eighth resistor R8 (with a resistance value R8); the first differential amplifier sub-circuit 224224 includes a third operational amplifier, a ninth resistor R9 (with a resistance value R9), a tenth resistor R10 (with a resistance value R10), an eleventh resistor R11 (with a resistance value R11), and a twelfth resistor R12 (with a resistance value R12).

When VIN is less than VTH1, the first switch tube Q1 of the first segment voltage conditioning sub-circuit 210 is closed, the second switch tube Q2 is opened, the first segment voltage conditioning sub-circuit 210 is turned on and works, the second segment voltage conditioning sub-circuit 220 is turned off and does not work, and then the output voltage is:

it should be noted that the output voltage can be biased and scaled up as required.

When VTH1 < VIN, the second switching tube Q2 of the first segmented voltage conditioning sub-circuit 210 is closed, the first switching tube Q1 is opened, the second segmented voltage conditioning sub-circuit 220 is turned on and operated, and the first segmented voltage conditioning sub-circuit 210 is turned off and operated, defining r9= r10= r11= r12, at this time

To achieve output continuity, the VTH2 voltage is set to:

and then the output voltage is:

namely, the input voltage VIN is conditioned, the output result is:

in the above embodiment, the input voltage signals are compared by dividing 2 input voltage ranges, and when the voltage amplitude of the input voltage signal falls into the corresponding input voltage range, the corresponding voltage conditioning sub-circuits (the first voltage conditioning sub-circuit and the second voltage conditioning sub-circuit) are turned on, so that 2-stage voltage signal conditioning is realized. According to the voltage signal conditioning method and device, the voltage signal conditioning is optimally designed, and the flexibility is improved aiming at automatic segmented conditioning of the voltage; the sampling range of voltage sampling conditioning is enlarged and the sampling precision and universality are improved aiming at different gain modes of voltage sampling of different sections, thereby widening the application scene of voltage sampling conditioning, improving the universality of the circuit and the accuracy of sampling conditioning and reducing the circuit cost.

In one embodiment, there is also provided a signal measurement device comprising a signal conditioning circuit as claimed in any one of the preceding claims.

For the detailed description of the signal conditioning circuit, reference is made to the description of the embodiments above, which is not repeated herein.

The technical features of the above embodiments can be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the above embodiments are not described, but should be considered as the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the claims. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A signal conditioning circuit, comprising:

a voltage threshold circuit configured to output a voltage threshold signal;

the segmented voltage conditioning circuit comprises a first segmented voltage conditioning sub-circuit and a second segmented voltage conditioning sub-circuit; the first segmented voltage conditioning sub-circuit is configured to condition the input voltage signal according to a received first conducting signal and output a first output voltage signal; the second segmented voltage conditioning sub-circuit is configured to condition the input voltage signal according to a received second conducting signal and output a second output voltage signal;

the selection circuit is respectively connected with the voltage threshold circuit, the first segmented voltage conditioning sub-circuit and the second segmented voltage conditioning sub-circuit; the selection circuit is configured to receive an input voltage signal and the voltage threshold signal; the selection circuit is further configured to output the first turn-on signal when the voltage value of the input voltage signal is less than a threshold value of the voltage threshold signal, and output the second turn-on signal when the voltage value of the input voltage signal is greater than the threshold value of the voltage threshold signal.

2. The signal conditioning circuit of claim 1 wherein the selection circuit comprises a first comparator and a second comparator;

a first input end of the first comparator is used for receiving the input voltage signal, a second input end of the first comparator is connected with an output end of the voltage threshold circuit, and an output end of the first comparator is connected with the first segmented voltage conditioning sub-circuit; the power supply end of the voltage threshold circuit is used for connecting a direct current power supply;

a first input end of the second comparator is connected to the output end of the voltage threshold circuit, a second input end of the second comparator is used for receiving the input voltage signal, and an output end of the second comparator is connected to the second segment voltage conditioning sub-circuit.

3. The signal conditioning circuit of claim 2 wherein the voltage threshold circuit comprises a first resistor and a second resistor;

the first end of the first resistor is connected with the direct current power supply, the second end of the first resistor is connected with the first end of the second resistor, the second end of the second resistor is connected with the ground wire, and the second input end of the first comparator and the first input end of the second comparator are respectively connected between the second end of the first resistor and the first end of the second resistor.

4. The signal conditioning circuit of claim 2 or 3 wherein the first segmented voltage conditioning sub-circuit comprises a first switching transistor and a first proportional operational amplifier sub-circuit;

the grid electrode of the first switching tube is connected with the output end of the first comparator, and the drain electrode of the first switching tube is used for accessing the input voltage signal; the source electrode of the first switch tube is connected with the non-inverting input end of the first proportional operational amplification sub-circuit, and the output end of the first proportional operational amplification sub-circuit is configured to output a first proportional amplification voltage signal.

5. The signal conditioning circuit of claim 4 wherein the second segmented voltage conditioning sub-circuit comprises a second switching tube, a second proportional operational amplifier sub-circuit, a first differential amplifier sub-circuit, and a continuous output regulation circuit;

the grid electrode of the second switching tube is connected with the output end of the second comparator, and the drain electrode of the second switching tube is used for accessing the input voltage signal; the source electrode of the second switch tube is connected with the non-inverting input end of the second proportional operational amplification sub-circuit, the output end of the second proportional operational amplification sub-circuit is configured to transmit a second proportional amplification voltage signal to the non-inverting input end of the first differential amplification sub-circuit, and the inverting input end of the first differential amplification sub-circuit is connected with the continuous output regulating circuit; the output terminal of the first differential amplification sub-circuit is configured to output a regulated second scaled amplified voltage signal.

6. The signal conditioning circuit of claim 5 wherein the first segmented voltage conditioning sub-circuit further comprises a first voltage follower sub-circuit;

and the non-inverting input end of the first voltage follower sub-circuit is connected with the output end of the first proportional operational amplifier sub-circuit.

7. The signal conditioning circuit of claim 6 wherein the second segmented voltage conditioning sub-circuit further comprises a second voltage follower sub-circuit;

and the non-inverting input end of the second voltage following sub-circuit is connected with the output end of the first differential amplification sub-circuit.

8. The signal conditioning circuit of claim 7, wherein the continuous output conditioning circuit comprises a third resistor and a fourth resistor;

9. The signal conditioning circuit of claim 5 wherein the first comparator is an operational comparator; the second comparator is an operational comparator.

10. A signal measurement device comprising a signal conditioning circuit as claimed in any one of claims 1 to 9.