Independent AD collector with multi-channel full-isolation structure

Abstract

The utility model discloses an independent AD collector with a multi-channel full-isolation structure. The independent AD collector comprises an MCU signal processor, a digital storage unit and a multi-channel digital isolation circuit, wherein the digital storage unit and the multi-channel digital isolation circuit are respectively connected with the MCU signal processor; the input end of any digital isolation circuit is connected with an AD chip. The input end of any AD chip is connected with a step-down circuit; the independent AD collector further comprises a power supply circuit, the power supply circuit is connected to the power supply isolation unit through a main power supply input and a power supply processing circuit, and a first electric output end of the power supply isolation unit is connected to the digital isolation circuits and the digital storage unit. The independent AD collector is characterized in that the circuit of each collection and measurement channel is standardized and modularized, and the collection and measurement of any channel combination can be easily realized; according to the utility model, high-efficiency measurement in the automatic test and measurement industry can be realized; and the production capacity and efficiency of factory production measurement are improved.

Description

Technical Field

[0001] The utility model relates to an AD collector, in particular to an independent AD collector with a multi-channel full isolation structure. Background Art

[0002] AD collector is an automated device with the function of on-site real-time data collection and processing. It has the functions of real-time collection, automatic storage, instant display, instant feedback, automatic processing, and automatic transmission. It provides guarantees for the authenticity, validity, real-time and availability of on-site data, thereby forming big data. Resources can be integrated and read through the AD collector.

[0003] In the prior art, the power supply of the AD collector adopts a non-isolated structure, which causes the space of the circuit board to be crowded, increases the difficulty of installing the circuit board, and further increases the cost of the circuit board.

[0004] The acquisition circuit design of traditional AD collectors is 4-channel or 8-channel, and the acquisition speed is limited. Designers need to design more AD collectors according to actual needs to solve the problem of acquisition efficiency.

[0005] In view of this, it is necessary to improve the traditional AD collector. Utility Model Content

[0006] In view of the shortcomings of the prior art, the technical problem to be solved by the utility model is to provide an independent AD collector with a multi-channel fully isolated structure. The purpose of designing the independent AD collector is: first, to reduce the space of the circuit board with its own isolated power supply, thereby reducing the cost; second, to increase

[0007] In order to solve the above technical problems, the utility model is implemented by the following scheme: the utility model is an independent AD collector with a multi-channel full isolation structure, including an MCU signal processor, and a digital storage unit and a multi-channel digital isolation circuit respectively connected to the MCU signal processor;

[0008] The input end of any digital isolation circuit is connected with an AD chip;

[0009] The input end of any AD chip is connected to a step-down circuit;

[0010] The independent AD collector also includes a power supply circuit, which has a total power supply input, and the total power supply input is connected to a power isolation unit via a power processing circuit. The first electrical output terminal of the power isolation unit is connected to each digital isolation circuit and a digital storage unit.

[0011] Furthermore, the digital isolation circuit has its own isolated power supply, and the SPI signal of the AD chip is isolated through a digital isolator.

[0012] Furthermore, in any one digital isolation circuit, the AD chip uses SPI communication and the digital isolation circuit to isolate the SPI signal;

[0013] The MCU signal processor is connected to any digital isolation circuit via an SPI interface, and the MCU signal processor reads the digital signal of each digital isolation circuit and performs data conversion.

[0014] Furthermore, the signal output interface of the MCU signal processor includes one of an Ethernet communication output interface and an RS485 communication output interface.

[0015] Furthermore, the second electrical output end of the power isolation unit is connected to the Ethernet communication output interface.

[0016] Furthermore, the Ethernet communication output interface or the RS485 communication output interface both use standard modbsu-rtu and modbus-tcp communication protocol outputs.

[0017] Further, the step-down circuit includes a resistor RI, a resistor RV1, a resistor RV2, a resistor RV3, a resistor RV4, a resistor RV, a resistor R1, a resistor R2, a capacitor CA, a capacitor CB and a capacitor CC;

[0018] The resistor RV1, the resistor RV2, and the resistor R1 are connected in sequence to form a first series circuit;

[0019] The resistor RV3, the resistor RV4, and the resistor R2 are connected in sequence to form a second series circuit;

[0020] The first terminal of the first series circuit is connected to IN1+circuit;

[0021] A first terminal of the second series circuit is connected to the IN1-circuit, and a resistor RI is connected between the IN1+circuit and the IN1-circuit;

[0022] The circuit between the resistor RV2 and the resistor R1 is provided with a first node, and the circuit between the resistor RV4 and the resistor R2 is provided with a second node, and the resistor RV is connected between the first node and the second node;

[0023] A capacitor CA and a capacitor CB connected in series are connected between the second end of the first series circuit and the second end of the second series circuit, and the circuit between the capacitor CA and the capacitor CB is grounded;

[0024] A capacitor CC is further connected between the second end of the first series circuit and the second end of the second series circuit;

[0025] The second end of the first series circuit and the second end output end of the second series circuit are connected to the AD chip.

[0026] Furthermore, the digital isolation circuit is provided with 24 circuits.

[0027] Compared with the prior art, the beneficial effects of the utility model are:

[0028] 1. The independent AD collector of the utility model is characterized by the standardization and modularization of the circuit of each acquisition and measurement channel, which can easily realize the acquisition and measurement of any channel combination.

[0029] 2. The circuit isolation chip of the independent AD collector of the utility model adopts the SPI parallel communication interface mode, which is read by the MCU signal processor, and can achieve ms-level update time for multiple signals, thereby realizing efficient measurement in the automated test and measurement industry; improving the production capacity and efficiency of factory production and measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a 24-channel digital isolation circuit diagram of an independent AD collector of the utility model.

[0031] Figure 2 for Figure 1 A single AD collector circuit diagram.

[0032] Figure 3 This is the voltage-reducing circuit diagram of the utility model. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model, so that the advantages and features of the utility model can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the utility model. In addition, the technical features involved in the different embodiments of the utility model described below can be combined with each other as long as they do not conflict with each other.

[0034] Embodiment 1: The specific structure of the utility model is as follows:

[0035] Please refer to the attached Figure 1-3The utility model discloses an independent AD collector with a multi-channel fully isolated structure, including an MCU signal processor, a digital storage unit and a multi-channel digital isolation circuit respectively connected to the MCU signal processor. The MCU signal processor adopts a chip of the STC15 series, and the MCU signal processor adopts an SPI interface to read the acquisition signal of each digital isolation circuit for data conversion. The digital isolation circuit is provided with a power supply, which is an isolated power supply. The digital isolation circuit is also provided with a NSIP8941 / CA-IS3641 digital chip, which is also called a digital isolator.

[0036] The input end of any digital isolation circuit is connected to an AD chip, and the AD chip adopts a CS5550 AD chip or a CS5463 AD chip. In any digital isolation circuit, the AD chip and the digital isolation circuit communicate through the SPI communication protocol; the MCU signal processor and any digital isolation circuit are connected through an SPI interface, and the MCU signal processor reads the digital signal of each digital isolation circuit and performs data conversion. Specifically, the AD chip uses the SPI communication method to input into the digital isolator with an isolated power supply, and the digital isolator with an isolated power supply realizes the synchronous isolation of the digital signal and the power supply, eliminating the independent power supply module, reducing peripheral devices, and thus reducing costs.

[0037] The input end of any AD chip is connected to a step-down circuit. The multi-channel digital isolation circuit of the utility model, the corresponding number of AD chips, and the corresponding number of step-down circuits form 24 acquisition and measurement channels. Each acquisition and measurement channel adopts a standard modular circuit design, which can realize different combinations of channels, such as 4-channel acquisition combination, 8-channel acquisition combination, 16-channel acquisition combination, and 24-channel acquisition combination. Among them, the 4-channel acquisition combination is a collection and measurement channel formed by arbitrarily selecting 4 channels from the 24 acquisition and measurement channels, the 8-channel acquisition combination is a collection and measurement channel formed by arbitrarily selecting 8 channels from the 24 acquisition and measurement channels, and the 16-channel acquisition combination is a collection and measurement channel formed by arbitrarily selecting 16 channels from the 24 acquisition and measurement channels.

[0038] Embodiment 2:

[0039] The independent AD collector also includes a power supply circuit, which is input by a total power supply, and the total power supply input is connected to a power isolation unit through a power processing circuit, and the first electrical output terminal of the power isolation unit is connected to each digital isolation circuit and a digital storage unit. The total power supply circuit is isolated by a power step-down isolation power supply to supply power to the 24-channel digital isolator and the circuit of the MCU signal processor, so that the total power supply circuit is isolated from the internal circuit.

[0040] Embodiment 3:

[0041] The signal output interface of the MCU signal processor includes an Ethernet communication output interface and an RS485 communication output interface. The second electrical output end of the power isolation unit is connected to the Ethernet communication output interface. The Ethernet communication output interface or the RS485 communication output interface both use standard modbsu-rtu and modbus-tcp communication protocols for output.

[0042] Embodiment 4:

[0043] The following is the specific circuit structure of the step-down circuit of the utility model:

[0044] The step-down circuit includes a resistor RI, a resistor RV1, a resistor RV2, a resistor RV3, a resistor RV4, a resistor RV, a resistor R1, a resistor R2, a capacitor CA, a capacitor CB and a capacitor CC;

[0045] The resistor RV1, the resistor RV2, and the resistor R1 are connected in sequence to form a first series circuit;

[0046] The resistor RV3, the resistor RV4, and the resistor R2 are connected in sequence to form a second series circuit;

[0047] The first terminal of the first series circuit is connected to IN1+circuit;

[0048] A first terminal of the second series circuit is connected to the IN1-circuit, and a resistor RI is connected between the IN1+circuit and the IN1-circuit;

[0049] The circuit between the resistor RV2 and the resistor R1 is provided with a first node, and the circuit between the resistor RV4 and the resistor R2 is provided with a second node, and the resistor RV is connected between the first node and the second node;

[0050] A capacitor CA and a capacitor CB connected in series are connected between the second end of the first series circuit and the second end of the second series circuit, and the circuit between the capacitor CA and the capacitor CB is grounded;

[0051] A capacitor CC is further connected between the second end of the first series circuit and the second end of the second series circuit;

[0052] The second end of the first series circuit and the second end output end of the second series circuit are connected to the AD chip.

[0053] Embodiment 5:

[0054] To sum up, the independent AD collector of the utility model is mainly divided into five parts: input, sampling, MCU data calculation, conversion output, and power supply; each channel of the input part is independently modularly designed, and each channel adopts AD chip plus digital isolation chip to achieve independent isolation of each channel. The digital chip communication method adopts SPI communication, and the MCU signal processor reads the signal of each channel. Through the standardized circuit design of each channel, any combination of multi-channel signal acquisition can be realized; the digital isolation chip adopts its own isolated power supply to reduce circuit board space and reduce costs, and the digital isolation chip with isolated power supply is used to realize digital isolation between AD output and MCU circuit. At the same time, there is no need to use an isolated power supply module to power the AD chip separately. The utility model only uses a digital isolation chip with power supply to realize power supply to the circuit of the signal input end, realize independent isolation of the measurement loop, reduce hardware circuits and reduce costs.

[0055] The utility model supports the collection of up to 24 voltage and current input signals; the input signal processing circuit adopts differential signal processing to AD to achieve high anti-interference and bidirectional collection of positive and negative signals; the channel isolation circuit collects current signals to achieve high-end or low-end collection, and does not need to worry about the common-mode voltage interference problem, and can be implemented in any industrial measurement environment. Through high isolation and voltage resistance processing, 1500V voltage can be directly input and measured, and the use of independent modular design can also greatly improve the data collection speed. The SPI communication interface is used to read by the MCU to achieve synchronous collection of multi-channel signals, and the fastest update of 24-channel signal measurement can be achieved in 10ms; data communication output is achieved through RS485 or Ethernet interface circuit, and standard modbsu-rtu and modbus-tcp communication protocols are adopted; the input power supply circuit is isolated from the input signal measurement circuit by an isolation power supply module, and the communication also adopts an isolation circuit to achieve complete electrical isolation between the input, output, and communication circuits.

[0056] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. An independent AD collector with a multi-channel fully isolated structure, characterized in that: It includes an MCU signal processor, and a digital storage unit and a multi-channel digital isolation circuit respectively connected to the MCU signal processor; The input end of any digital isolation circuit is connected with an AD chip; The input end of any AD chip is connected to a step-down circuit; The independent AD collector also includes a power supply circuit, which has a total power supply input, which is connected to a power isolation unit via a power processing circuit. The first electrical output terminal of the power isolation unit is connected to each digital isolation circuit and a digital storage unit.

2. The independent AD collector with a multi-channel fully isolated structure according to claim 1, characterized in that: The digital isolation circuit has its own isolated power supply, and the SPI signal of the AD chip is isolated through the digital isolator.

3. The independent AD collector with a multi-channel fully isolated structure according to claim 1, characterized in that: In any digital isolation circuit, the AD chip uses SPI communication and the digital isolation circuit to isolate the SPI signal; The MCU signal processor is connected to any digital isolation circuit via an SPI interface, and the MCU signal processor reads the digital signal of each digital isolation circuit and performs data conversion.

4. The independent AD collector with a multi-channel fully isolated structure according to claim 1, characterized in that: The signal output interface of the MCU signal processor includes an Ethernet communication output interface and an RS485 communication output interface.

5. The independent AD collector with a multi-channel fully isolated structure according to claim 4, characterized in that: The second electrical output end of the power isolation unit is connected to the Ethernet communication output interface.

6. The independent AD collector with a multi-channel fully isolated structure according to claim 4, characterized in that: The Ethernet communication output interface or RS485 communication output interface adopts standard modbsu-rtu and modbus-tcp communication protocol output.

7. The independent AD collector with a multi-channel fully isolated structure according to claim 1, characterized in that: The step-down circuit includes a resistor RI, a resistor RV1, a resistor RV2, a resistor RV3, a resistor RV4, a resistor RV, a resistor R1, a resistor R2, a capacitor CA, a capacitor CB and a capacitor CC; The resistor RV1, the resistor RV2, and the resistor R1 are connected in sequence to form a first series circuit; The resistor RV3, the resistor RV4, and the resistor R2 are connected in sequence to form a second series circuit; The first terminal of the first series circuit is connected to IN1+circuit; A first terminal of the second series circuit is connected to the IN1-circuit, and a resistor RI is connected between the IN1+circuit and the IN1-circuit; The circuit between the resistor RV2 and the resistor R1 is provided with a first node, and the circuit between the resistor RV4 and the resistor R2 is provided with a second node, and the resistor RV is connected between the first node and the second node; A capacitor CA and a capacitor CB connected in series are connected between the second end of the first series circuit and the second end of the second series circuit, and the circuit between the capacitor CA and the capacitor CB is grounded; A capacitor CC is further connected between the second end of the first series circuit and the second end of the second series circuit; The second end of the first series circuit and the second end output end of the second series circuit are connected to the AD chip.

8. The independent AD collector with a multi-channel fully isolated structure according to claim 1, characterized in that: The digital isolation circuit is provided with 24 circuits.

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