High-speed SPI communication system based on double-drive isolation

Abstract

The utility model discloses a high-speed SPI (Serial Peripheral Interface) communication system based on double-drive isolation, another auxiliary SPI drive is added to an SPI master station side to form a double-SPI drive structure, and the auxiliary SPI is used as a slave station working module. An SPI-Master is configured to serve as a master station data sending module, an SPI-Assist is configured to serve as a slave station data receiving module, and the whole SPI dual-drive structure forms a full-duplex transceiving system. Through the signal waveform checked by the oscilloscope, the returned MOSI signal and CLK signal are almost not delayed. The input data is sampled according to the clock signal without clock phase deviation, and the sampled data is accurate. The method is mainly applied to power supply isolation high-speed communication design in the power electronic industry.

Description

Technical Field

[0001] The utility model relates to a synchronous serial communication protocol, in particular to a high-speed SPI communication system based on dual-drive isolation. Background Art

[0002] SPI is a synchronous serial communication protocol mainly used for data communication between embedded systems and peripherals. It has the characteristics of full duplex, high speed and simple hardware structure. Usually, 4 wires are used for communication, including the clock line (SCLK), chip select line (CS), master output slave input line (MOSI) and master input slave output line (MISO). The basic working principle of SPI communication is realized through data transmission between the master device and the slave device. The master device is responsible for initializing the data transmission frame and selects and communicates with the slave device through the clock signal line (SCLK) and chip select signal line (CS). Data is sent from the master device to the slave device through the MOSI line, and at the same time, the slave device sends the data back to the master device through the MISO line, realizing full duplex communication. The data transmission rate supported by SPI communication can range from several kbps to several hundred Mbps, and the specific rate depends on the specifications and performance of the master device and the slave device.

[0003] Existing technologies and their defects:

[0004] Existing SPI communication technologies are applied to embedded non-isolated systems, and the structure is as Figure 1 shown. The SPI master (SPI-Master) issues the chip select signal CS, the clock signal CLK, and the data transmission signal MOSI, and receives the data input signal MISO from the slave (SPI-Slave). In this structural state, the communication rate is relatively high, up to several tens of Mbps.

[0005] When applied to an isolated system, the conventional operation method is to add a digital isolation device between the master-slave communication to electrically isolate the signals of the master-slave communication, and its structure is as Figure 2 shown.

[0006] Due to the signal delay of the isolation device, the reference clock CLK1 for data transmission and the reference clock CLK2 for data readback will have a phase offset, which will seriously affect the upper limit of the SPI communication rate. The degree of influence varies according to the electrical delay parameters of the isolation device. In severe cases, data communication errors may occur even at several kbps. Therefore, a method is needed to eliminate the problem of SPI data sampling errors caused by device signal delays in an embedded isolation system.

[0007] In view of this, the present utility model is specifically proposed. Content of the Utility Model

[0008] The purpose of the present utility model is to provide a high-speed SPI communication system based on dual-drive isolation to solve the above-mentioned technical problems existing in the prior art.

[0009] The purpose of the present utility model is achieved through the following technical solutions:

[0010] In the high-speed SPI communication system based on dual-drive isolation of the present utility model, another auxiliary SPI driver is added to the SPI master station to form a dual-SPI drive structure, and the auxiliary SPI serves as a slave station working module.

[0011] Compared with the prior art, the high-speed SPI communication system based on dual-drive isolation provided by the present utility model adopts the dual-drive SPI isolation method. By viewing the signal waveform through an oscilloscope, there is almost no delay in the back-transmitted MOSI signal and CLK signal. Sampling the input data according to this clock signal has no clock phase deviation, and the sampled data is accurate. It is mainly applied to the isolated high-speed communication design of power supplies in the power electronics industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 FIG. is a schematic diagram of the application of the prior art SPI communication technology in an embedded non-isolated system.

[0013] Figure 2 FIG. is a schematic diagram of adding a digital isolation device between the master-slave communication to electrically isolate the signals of the master-slave communication when applying the prior art conventional operation method to an isolated system.

[0014] Figure 3 FIG. is a schematic diagram of the structure of dual-drive isolation in an embodiment of the present utility model.

[0015] Figure 4 FIG. is a schematic diagram of viewing the signal waveform of the prior art conventional isolation method through an oscilloscope.

[0016] Figure 5 FIG. is a schematic diagram of the signal waveform viewed through an oscilloscope when the dual-drive SPI isolation method is adopted in an embodiment of the present utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0017] The technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model; obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments, which do not constitute a limitation to the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0018] First, the following explanations are given for the terms that may be used in this article:

[0019] The term "and / or" means that either or both of the two can be realized. For example, X and / or Y means that it includes three cases: the case of "X" or "Y" and the case of "X and Y".

[0020] Descriptions with terms such as "comprising", "including", "containing", "having" or other similar semantics should be interpreted as non-exclusive inclusion. For example: including a certain technical feature element (such as raw materials, components, ingredients, carriers, dosage forms, materials, dimensions, parts, components, mechanisms, devices, steps, processes, methods, reaction conditions, processing conditions, parameters, algorithms, signals, data, products or articles, etc.) should be interpreted as not only including the clearly listed certain technical feature element, but also including other technical feature elements well-known in the art that are not clearly listed.

[0021] The term "consisting of..." means excluding any technical feature element that is not clearly listed. If this term is used in a claim, this term will make the claim a closed type, making it not contain technical feature elements other than the clearly listed technical feature elements, except for the related conventional impurities. If this term only appears in a certain clause of the claim, then it only limits the elements clearly listed in that clause, and the elements recorded in other clauses are not excluded from the overall claim.

[0022] It must have a specific orientation, be constructed and operated in a specific orientation, so it cannot be understood as a limitation to this article.

[0023] The content not described in detail in the embodiments of the present utility model belongs to the prior art well-known to those skilled in the art. For those conditions not specified in the embodiments of the present utility model, they are carried out according to the conventional conditions in the art or the conditions recommended by the manufacturer. For the reagents or instruments used in the embodiments of the present utility model without indicating the manufacturer, they are all conventional products that can be obtained through commercial purchase.

[0024] The high-speed SPI communication system based on dual-drive isolation of the present utility model adds another auxiliary SPI driver on the SPI master side to form a dual-SPI drive structure, and the auxiliary SPI works as a slave station working module.

[0025] Configure SPI-Master as the master station data sending module, configure SPI-Assist as the slave station data receiving module, and the entire SPI dual-drive structure constitutes a full-duplex transceiver system.

[0026] Adding another auxiliary SPI driver on the SPI master side forms a dual-SPI drive structure. The auxiliary SPI works in the slave station mode, and the input clock signal CLK3 has undergone digital isolation positive and negative correction, canceling the phase difference caused by the one-way transmission delay.

[0027] The software configures the SPI-Master to work in the master station data transmission mode and the SPI-Assist to work in the slave station data reception mode. The entire SPI dual-drive structure forms a full-duplex transceiver system.

[0028] This system automatically shields the problem of phase deviation of clock and data signals caused by digital isolators, so that in the isolation system, the high-speed working rate of SPI is still not affected.

[0029] In summary, the high-speed SPI communication system based on dual-drive isolation in the embodiment of the present invention adopts the dual-drive SPI isolation method. Through the signal waveform viewed by an oscilloscope, the backhaul MOSI signal and CLK signal have almost no delay. Sampling the input data according to this clock signal has no clock phase deviation, and the sampled data is accurate. It is mainly applied to the isolation high-speed communication design of power supplies in the power electronics industry.

[0030] In order to more clearly show the technical solutions provided by the present invention and the technical effects produced, the following uses specific embodiments to describe in detail what is provided in the embodiments of the present invention.

[0031] Embodiment 1

[0032] The dual-drive isolation structure of the present invention is as Figure 3 shown. Another auxiliary SPI driver is added to the SPI master station to form a dual-SPI drive structure. The auxiliary SPI works in the slave station mode, and the input clock signal CLK3 has undergone positive and negative correction of digital isolation, canceling the phase difference caused by one-way transmission delay. The software configures the SPI-Master to work in the master station data transmission mode and the SPI-Assist to work in the slave station data reception mode. The entire SPI dual-drive structure forms a full-duplex transceiver system. This system automatically shields the problem of phase deviation of clock and data signals caused by digital isolators, so that in the isolation system, the high-speed working rate of SPI is still not affected.

[0033] Detection and experimental verification

[0034] The dual-drive scheme proposed by the present invention is compared and verified with the traditional scheme. The master station sends the CLK signal and data, and the slave station backhauls the same data. By viewing the signal waveform of the conventional isolation method with an oscilloscope as Figure 4 shown, there is a transmission delay of about 16 ns between the sent CLK signal and the backhaul MOSI signal, and this transmission delay will affect the accuracy of data sampling.

[0035] Similarly, using the dual-drive SPI isolation method, the signal waveform viewed by an oscilloscope is as Figure 5As shown, the backhaul MOSI signal and the CLK signal have almost no delay. Sampling the input data according to this clock signal has no clock phase deviation, and the sampled data is accurate and error-free.

[0036] As described above, it is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims. The information disclosed in the background art part of this article is only intended to deepen the understanding of the overall background art of the present invention, and should not be regarded as an admission or an indication in any form that this information constitutes the prior art already known to those skilled in the art.

Claims

1. A high-speed SPI communication system based on dual-drive isolation, characterized in that: Add another auxiliary SPI driver to the SPI master station to form a dual SPI driver structure, and the auxiliary SPI works as a slave station working module.

2. The high-speed SPI communication system based on dual-drive isolation according to claim 1, wherein Configure SPI-Master as the master data sending module and SPI-Assist as the slave data receiving module. The entire SPI dual-drive structure constitutes a full-duplex transceiver system.

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