Multipath signal analog-to-digital conversion circuit

Abstract

The utility model relates to the technical field of signal transmission and processing, and discloses a multipath signal analog-to-digital conversion circuit. Comprising an amplification unit, an analog-to-digital conversion unit and a microcontroller. The amplification unit adopts a four-channel design, each channel consists of an operational amplification circuit and a digital potentiometer, and the amplification factor can be independently adjusted; the analog-to-digital conversion unit supports multi-channel parallel processing, so that the conversion efficiency is improved; and the microcontroller monitors in real time and dynamically adjusts the magnification times, so that the signal quality is ensured. The circuit solves the problems that the amplification factor is fixed and the dynamic adjustment capability is lacked when a traditional analog-to-digital conversion circuit processes multiple paths of analog signals, is suitable for a complex signal environment, effectively avoids signal distortion, and improves the signal adaptability.

Description

TECHNICAL FIELD

[0001] The utility model relates to analog-digital conversion technical field discloses a kind of multi-channel signal analog-digital conversion circuit. BACKGROUND

[0002] Traditional analog-digital conversion circuit has obvious limitation when processing multi-channel analog signal, such as fixed amplification, limited channel number, and lack of dynamic adjustment capability. These defects lead to signal distortion, low conversion efficiency and difficulty in adapting to different signal strengths in complex signal environment. SUMMARY

[0003] In view of the above technical deficiencies, the utility model aims to provide a kind of multi-channel signal analog-digital conversion circuit, to solve the problems existing in the prior art.

[0004] To solve the above technical problems, the utility model adopts the following technical scheme:

[0005] In the first aspect, the utility model provides a kind of multi-channel signal analog-digital conversion circuit, and the analog-digital conversion circuit includes amplification unit, analog-digital conversion unit and microcontroller;

[0006] The amplification unit is used for amplifying the input analog signal;

[0007] The analog-digital conversion unit is responsible for converting the amplified analog signal into digital signal;

[0008] The microcontroller is used for monitoring the digital signal output by the analog-digital conversion unit, and adjusting the amplification multiple of the amplification unit according to the characteristics of the signal.

[0009] Preferably, in a possible implementation manner of the first aspect, the amplification unit includes a four-channel amplification circuit composed of four operational amplifiers, each channel is composed of an operational amplifier circuit, each operational amplifier circuit receives an analog signal and outputs an amplified analog signal.

[0010] Preferably, in a possible implementation manner of the first aspect, the operational amplifier circuit includes an operational amplifier, a resistor R1, a resistor R2, a resistor Ri, a capacitor Co, a capacitor C1, a capacitor Ci and a digital potentiometer, the negative pin of the operational amplifier receives an input signal Vi through the resistor Ri and the capacitor Ci, wherein the capacitor Ci is used for filtering or decoupling, one end of the resistor R1 is connected with the positive pin of the operational amplifier, and the other end is connected with power supply, one end of the resistor R2 is connected with the positive pin of the operational amplifier, and the other end is grounded, one end of the capacitor Co is connected with the output pin of the operational amplifier, and the other end is the output end Vo of the operational amplifier circuit, one end of the capacitor C1 is connected with the positive pin of the operational amplifier, and the other end is grounded, one end of the digital potentiometer is connected with the negative pin of the operational amplifier, and the other end is connected with the output pin of the operational amplifier.

[0011] Preferably, in a possible implementation form of the first aspect, the digital potentiometer controls the resistance size through the microcontroller, so that the digital potentiometer changes its resistance value to control the amplification multiple of the operational amplifier circuit.

[0012] Preferably, in a possible implementation form of the first aspect, the analog-to-digital conversion unit comprises a multi-channel parallel analog-to-digital converter which simultaneously receives four amplified analog signals through pins and converts them into four digital signals.

[0013] Preferably, in a possible implementation form of the first aspect, the microcontroller is connected with the digital potentiometer in the four-channel amplification circuit through a preset serial communication protocol to control the amplification multiple of the amplification circuit.

[0014] Preferably, in a possible implementation form of the first aspect, the microcontroller adjusts the resistance value of the corresponding digital potentiometer according to the received digital signal.

[0015] The beneficial effects of the present application are as follows: a multi-channel signal analog-to-digital conversion circuit is provided, which integrates an amplification unit, an analog-to-digital conversion unit and a microcontroller. The amplification unit adopts a four-channel design, each channel being independently adjustable to ensure that the signal can be appropriately amplified under different intensities; the analog-to-digital conversion unit supports multi-channel parallel processing to improve conversion efficiency; the microcontroller monitors the digital signal characteristics in real time and dynamically adjusts the amplification multiple to ensure signal quality. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiment or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0017] Figure 1 A multi-channel signal analog-to-digital conversion circuit structure diagram is provided for the present application.

[0018] Figure 2 An operational amplifier circuit diagram is provided for the present application. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present application will be described clearly and completely in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, not all embodiments.

[0020] Embodiment one: asFigure 1 The utility model provides a kind of multi-channel signal analog-digital conversion circuit, comprising:

[0021] Amplification unit, analog-digital conversion unit and microcontroller.

[0022] Amplification unit includes four-channel amplification circuit by four-way operational amplifier, for amplification processing to input analog signal.

[0023] Analog-digital conversion unit includes multi-channel parallel analog-digital converter, responsible for converting amplified analog signal into digital signal.

[0024] Microcontroller includes microcontroller, for monitoring the digital signal output by analog-digital conversion unit, according to the characteristics of signal adjustment amplification multiple of amplification circuit.

[0025] Specifically, in the embodiment, four-way operational amplifier adopts LM324, and LM324 is composed of four high-gain amplifiers. Internal frequency compensation is provided to enable high-gain amplifiers to work in a wide frequency range.

[0026] Four-channel amplification circuit is formed using LM324, and each channel is composed of an operational amplifier circuit. Each operational amplifier circuit receives an analog signal and outputs an amplified analog signal. Operational amplifier circuit is as shown in Figure 2 .

[0027] Operational amplifier circuit includes operational amplifier, resistance R1, resistance R2, resistance Ri, capacitor Co, capacitor C1, capacitor Ci and digital potentiometer. The negative pin of operational amplifier receives input signal Vi through resistance Ri and capacitor Ci, wherein capacitor Ci is used for filtering or decoupling. One end of resistance R1 is connected to the positive pin of operational amplifier, and the other end is connected to power supply. One end of resistance R2 is connected to the positive pin of operational amplifier, and the other end is grounded. One end of capacitor Co is connected to the output pin of operational amplifier, and the other end is the output end Vo of operational amplifier circuit. One end of capacitor C1 is connected to the positive pin of operational amplifier, and the other end is grounded. One end of digital potentiometer is connected to the negative pin of operational amplifier, and the other end is connected to the output pin of operational amplifier.

[0028] In the embodiment, the value of resistance R1 is 100 , the value of resistance R2 is 100 , the value of resistance Ri is 10 , the value of capacitor Co is 0.1 , the value of capacitor C1 is 10 , and the value of capacitor Ci is 0.01 .

[0029] The negative pole pin of the operational amplifier in the operational amplifier circuit is pin 2, pin 6, pin 9 and pin 13 in the LM324, the positive pole pin of the operational amplifier is pin 3, pin 5, pin 10 and pin 12 in the LM324, and the output pin of the operational amplifier is pin 1, pin 7, pin 8 and pin 14.

[0030] In the embodiment, the multi-channel parallel analog-digital converter adopts ADC0809, receives four amplified analog signals output by the amplification unit through IN0, IN1, IN2 and IN3 respectively, and is connected with the microcontroller to transmit the converted digital signal to the microcontroller.

[0031] The microcontroller adopts STM32 series STM32F103C8T6 model chip, the START pin in the ADC0809 is connected with the PA2 pin in the STM32, responsible for starting the A / D conversion signal, the EOC pin is connected with the PA3 pin, responsible for the conversion end state signal, the EOC output signal is 0, the conversion is being carried out, it is 1, the conversion is completed, the next output operation can be carried out, that is, when the A / D conversion is completed, a high level is output at this end (low level during conversion); the OE pin is connected with the PA4 pin, responsible for the output enable signal, this pin is an input terminal, high level is effective, when the A / D conversion is completed, a high level is input at this end, so as to open the output triode and output digital quantity; the CLOCK pin is connected with the PA7 pin, responsible for the clock signal, the ADC0809 has no internal clock circuit, and needs to provide a clock pulse signal by external clock, the clock frequency range is 10KHz-1280KHz; the ALE pin is connected with the PA6 pin, as an address latch enable signal; the ADD_A, ADD_B, ADD_C pins are connected with the PA5, PB2, PB5 pins respectively, as channel selection pins, one of which is used as an input channel of the analog signal; the D0, D1, D2, D3 pins are connected with the PB8, PB9, PB10, PB11 pins respectively, as digital signal output channels.

[0032] The digital potentiometer used in the embodiment is MAX5438, the SCLK pins of the four digital potentiometers are connected with the PA8, PA11, PA14 and PB13 in the STM32 respectively, to provide a clock signal for serial communication; the DIN pins are connected with the PA9, PA12, PA15 and PB14 in the STM32 respectively, to receive digital signals from the microcontroller; the CS pins are connected with the PA10, PA13, PB12 and PB15 in the STM32 respectively, to control the enable state of the MAX5438.

[0033] The microcontroller receives the digital signal transmitted by the analog-to-digital conversion unit, determines whether the amplification multiple of the current amplification circuit meets the requirements according to the digital signal, and if not, adjusts the resistance value of the digital potentiometer to control the amplification multiple of the amplification circuit.

[0034] Specifically, the microcontroller reads and stores the digital signals. These signals are pre-processed, including filtering, averaging, etc., to improve the accuracy and stability of the signals. Then, the microcontroller analyzes the characteristics of these digital signals (including amplitude, rate of change, etc.) according to a pre-set lookup table to determine whether the amplification multiple of the current amplification circuit meets the requirements.

[0035] The microcontroller compares the processed digital signals with pre-set thresholds or ranges to determine whether the current amplification multiple is too high, too low, or moderate. If the result shows that the amplification multiple needs to be adjusted, the microcontroller will calculate the specific value or proportion that needs to be adjusted according to the adjustment direction and the expected target.

[0036] The microcontroller sends serial communication signals to the digital potentiometer through the specified control pin. These signals include clock signals (SCLK), data signals (DIN), and enable signals (CS). Before sending data, the microcontroller first enables the corresponding digital potentiometer through the CS pin. Then, the microcontroller provides clock signals through the SCLK pin to control the rate and synchronization of data transmission. In each clock cycle, the microcontroller sends one or more bits of data to the digital potentiometer through the DIN pin, which represents the adjustment instruction.

[0037] After receiving the serial data from the microcontroller, the digital potentiometer adjusts its internal resistance value according to the data content. Since one end of the digital potentiometer is connected to the negative pin of the operational amplifier, and the other end is connected to the output pin of the operational amplifier, the adjustment of the resistance value will directly affect the amplification multiple of the amplification circuit.

[0038] After the adjustment is completed, the microcontroller reads the digital signals output by the analog-to-digital conversion unit again to verify whether the amplification multiple has been adjusted as expected. If the expected effect has not been achieved, the microcontroller repeats the above steps for fine-tuning.

[0039] Obviously, those skilled in the art can make various modifications and variations to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application also intends to include these modifications and variations.

Claims

1. A multi-channel signal analog-to-digital conversion circuit, characterized by comprising: The analog-digital conversion circuit comprises an amplification unit, an analog-digital conversion unit and a microcontroller; The amplification unit is configured to amplify the input analog signal; The amplification unit comprises a four-channel amplification circuit composed of four operational amplifiers, each channel being composed of an operational amplifier circuit, each operational amplifier circuit receiving an analog signal and outputting an amplified analog signal; The analog-digital conversion unit is configured to convert the amplified analog signal into a digital signal; The analog-digital conversion unit comprises a multi-channel parallel analog-digital converter which receives four amplified analog signals simultaneously through pins and converts them into four digital signals; The microcontroller is configured to monitor the digital signal output by the analog-digital conversion unit and adjust the amplification factor of the amplification unit according to the characteristics of the signal.

2. A multi-channel signal analog-to-digital conversion circuit according to claim 1, characterized in that, The operational amplifier circuit comprises an operational amplifier, a resistor R1, a resistor R2, a resistor Ri, a capacitor Co, a capacitor C1, a capacitor Ci and a digital potentiometer, the negative pin of the operational amplifier receives an input signal Vi through the resistor Ri and the capacitor Ci, wherein the capacitor Ci is configured to filter or decouple, one end of the resistor R1 is connected to the positive pin of the operational amplifier, and the other end is connected to the power supply, one end of the resistor R2 is connected to the positive pin of the operational amplifier, and the other end is connected to the ground, one end of the capacitor Co is connected to the output pin of the operational amplifier, and the other end is the output terminal Vo of the operational amplifier circuit, one end of the capacitor C1 is connected to the positive pin of the operational amplifier, and the other end is connected to the ground, one end of the digital potentiometer is connected to the negative pin of the operational amplifier, and the other end is connected to the output pin of the operational amplifier.

3. A multi-channel signal analog-to-digital conversion circuit according to claim 2, characterized in that, The digital potentiometer controls the amplification factor of the operational amplifier circuit by changing its resistance value under the control of the microcontroller.

4. The multi-channel signal analog-to-digital conversion circuit according to claim 1, wherein, The microcontroller is connected to the digital potentiometer in the four-channel amplification circuit through a pre-set serial communication protocol to control the amplification factor of the amplification circuit.

5. A multi-channel signal analog-to-digital conversion circuit according to claim 4, characterized in that, The microcontroller adjusts the resistance value of the corresponding digital potentiometer according to the received digital signal.

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