Communication system and communication method based on daisy chain

Abstract

The embodiment of the invention provides a communication system and method based on a daisy chain, belongs to the technical field of communication, and is applied to battery module detection communication, the system comprises a plurality of differential transceivers in communication connection with a main control chip, the differential transceivers and battery units of the battery modules are arranged in a one-to-one correspondence mode, and the differential transceivers are connected with the main control chip in a one-to-one correspondence mode. Each differential transceiver establishes communication based on the improved daisy chain; wherein the improved daisy chain is constructed based on direct current coupling; each differential transceiver is integrated with an independent AFE chip and is used for executing battery parameter acquisition of the corresponding battery unit; and each differential transceiver is used for transmitting the battery parameters of the corresponding battery unit back to the main control chip through differential signals. The scheme of the invention has remarkable technical effects in the aspects of improving communication efficiency, reducing cost and enhancing system integration.

Description

Technical Field

[0001] The present invention relates to the field of communication technology, and in particular to a daisy chain-based communication system and a daisy chain-based communication method. Background Art

[0002] With the rapid development of new energy vehicles and energy storage systems, the importance of battery management systems (BMS) in modern battery packs has become increasingly prominent. The core task of the BMS system is to monitor and manage the status of battery cells in real time to ensure the safety and efficiency of the battery. In order to achieve precise management of large-scale battery packs, the BMS system usually needs to transmit key information such as battery cell voltage and temperature through a reliable communication network. CCS (Cells Contact System, integrated busbar) technology is widely used in this scenario, aiming to improve the integration of battery modules and data acquisition efficiency.

[0003] In the CCS system, daisy chain communication is a commonly used communication method, which connects multiple devices in series to achieve high-speed and efficient data transmission. However, with the expansion of the scale of battery packs, the traditional daisy chain communication method has exposed a series of technical problems in practical applications. First of all, traditional CCS systems often rely on large-sized isolation devices to ensure electrical isolation of signal transmission. These isolation devices not only take up a lot of circuit board space, but also restrict the miniaturization of the BMS system. In addition, in order to cope with the high-voltage environment of multi-string cascaded battery packs, the system must use high-voltage resistant devices, which significantly increases the cost of the overall chip.

[0004] Another important issue is that existing communication systems often require a large number of peripheral devices to achieve signal transmission and isolation. As the complexity of the CCS system increases, the number of peripheral devices also continues to increase, which not only increases the difficulty of circuit design, but also makes the latest CCS pack process face many challenges during the integration process. The large number of peripheral devices makes it difficult to achieve efficient integration of the entire system during production and assembly, which ultimately leads to an increase in system size and cost.

[0005] In summary, the current CCS system has the following main deficiencies in communication: the isolation device is too large, which is not conducive to the miniaturization of the BMS system; the need to use high-voltage devices increases the cost of the overall chip; and too many peripheral devices make it difficult to achieve efficient integration in the CCS pack process. These problems have seriously restricted the application and development of the CCS system in modern battery management. Summary of the invention

[0006] The purpose of the embodiments of the present invention is to provide a daisy chain-based communication system and communication method, so as to at least solve the problems of difficulty in miniaturization and high component cost in existing daisy chain communication solutions when solving the communication requirements of CCS systems.

[0007] In order to achieve the above object, the first aspect of the present invention provides a daisy chain-based communication system, which is applied to battery module detection communication, and the system includes:

[0008] Multiple differential transceivers are communicatively connected to the main control chip, each differential transceiver is arranged in one-to-one correspondence with the battery cell of each battery module, and each differential transceiver establishes communication based on an improved daisy chain; wherein the improved daisy chain is constructed based on DC coupling; each differential transceiver integrates an independent AFE chip for executing battery parameter acquisition of the corresponding battery cell; each differential transceiver is used to transmit the battery parameters of the corresponding battery cell back to the main control chip through a differential signal.

[0009] Optionally, the differential communication pins of each AFE chip are connected in series via a differential line; the differential communication signal and the single-ended signal of each AFE chip are multiplexed and transmitted on the same pin.

[0010] Optionally, each differential transceiver includes: a downward transceiver, used to collect differential data of upstream / downstream nodes and transmit the corresponding differential data to the next node; a single-ended receiving module, used to collect single-ended signals of corresponding battery cells or upstream / downstream nodes; a wake-up module, used to wake up the corresponding differential transceiver when the input signal is triggered; and a calibration module, used to perform calibration functions in an ATE environment.

[0011] Optionally, the downward transceiver includes a transmitter and a receiver; the transmitter is used to output a pseudo differential signal; and the receiver is used to clamp the common mode value of the comparator to a corresponding preset level when in an upward receiver or a downward receiver.

[0012] Optionally, the transmitter is composed of an output buffer of two inverter structures and a deep N-well MOS tube; wherein the upward transmitting end of the transmitter is a deep N-well NMOS tube; the downward transmitting end of the transmitter is a deep N-well PMOS tube; the well potentials of the deep N-well NMOS tube and the deep N-well PMOS tube are both floating.

[0013] Optionally, the upward transmitting end is configured with a boost charge pump, which is used to provide a first preset amount of boost by configuring the charge pump to be enabled when the common mode level on the differential line is higher than a first preset value; the downward transmitting end is configured with a buck charge pump, which is used to provide a second preset amount of buck by configuring the charge pump to be enabled when the common mode level on the differential line is lower than a second preset value.

[0014] Optionally, the receiver is short-circuited with a preset value resistor; the receiver clamps the common mode value of the comparator in the receiver to a preset level through the common mode of the preset voltage to the ground; wherein, when the receiver is an upward receiver, the preset level is the preset voltage; when the receiver is a downward receiver, the preset level is the sum of the preset voltage and the system power supply voltage.

[0015] The second aspect of the present invention provides a daisy chain-based communication method, which is applied to battery module detection communication. The method is implemented based on the daisy chain-based communication system mentioned in the claim, and the method includes: responding to an input signal trigger, waking up the corresponding differential transceiver, and determining a signal processing scheme based on the input signal; executing the corresponding signal processing scheme, processing the input signal, and obtaining an output signal; determining a signal flow direction based on the output signal, and transmitting the output signal to the next node based on the corresponding signal flow direction; if no signal activity occurs within a preset time, controlling the corresponding differential transceiver to enter a sleep mode.

[0016] Optionally, the signal processing scheme is determined based on the input signal, including: if the input signal is a battery parameter acquisition signal of the corresponding battery unit, then the corresponding signal processing scheme is to process the acquisition signal into a corresponding transmission signal; if the input signal is an input signal of an upstream / downstream node, then the corresponding signal processing scheme is a signal relay scheme.

[0017] On the other hand, the present invention provides a computer-readable storage medium having instructions stored thereon, which, when executed on a computer, enables the computer to execute the above-mentioned daisy chain-based communication method.

[0018] Through the above technical solution, the solution of the present invention establishes communication with the main control chip through multiple differential transceivers, each differential transceiver is set in one-to-one correspondence with the corresponding battery unit, and an independent AFE chip is integrated for collecting battery parameters. This design solves the problems of large size of isolation devices and numerous peripheral devices in traditional systems through an improved daisy chain communication method and based on the construction of DC coupling. Through DC coupling technology, the system effectively reduces the dependence on large-size isolation devices, thereby helping to achieve the miniaturization of the BMS system. At the same time, the differential transceiver transmits the collected battery parameters back to the main control chip through differential signals. This signal transmission method has strong anti-interference ability and improves the transmission integrity and reliability of the signal. In addition, each differential transceiver independently integrates an AFE chip, so that the system can collect and process battery parameters more efficiently, reduce the number of peripheral devices, and simplify the integration difficulty of the CCS pack process. Overall, the system has significant technical effects in improving communication efficiency, reducing costs and enhancing system integration.

[0019] Other features and advantages of the embodiments of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the embodiments of the present invention, but do not constitute a limitation on the embodiments of the present invention. In the accompanying drawings:

[0021] Figure 1 is a system structure diagram of a daisy chain-based communication system provided by an embodiment of the present invention;

[0022] Figure 2 is a structural schematic diagram of a differential transceiver provided in one embodiment of the present invention;

[0023] Figure 3 is a circuit diagram of a transmitter provided in one embodiment of the present invention;

[0024] Figure 4 is a circuit diagram of a receiver provided by an embodiment of the present invention;

[0025] Figure 5 It is a flow chart of the steps of a daisy chain-based communication method provided in one embodiment of the present invention. DETAILED DESCRIPTION

[0026] The specific implementation of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present invention, and is not used to limit the present invention.

[0027] Figure 1 FIG. 1 is a system structure diagram of a daisy chain-based communication system provided by an embodiment of the present invention. Figure 1 As shown, an embodiment of the present invention provides a communication system based on a daisy chain, the system comprising: a plurality of differential transceivers communicatively connected to a main control chip, each differential transceiver being arranged in one-to-one correspondence with a battery cell of each battery module, and each differential transceiver establishing communication based on an improved daisy chain; wherein the improved daisy chain is constructed based on DC coupling; each differential transceiver integrates an independent AFE chip for executing battery parameter acquisition of a corresponding battery cell; each differential transceiver is used to transmit the battery parameters of the corresponding battery cell back to the main control chip via a differential signal. Figure 1In the , URTXP stands for Upstream Transmit Positive. This is part of the positive signal line in the differential communication link, used to send data from the current node to the upstream node. URTXP is the positive phase signal line in the differential pair, and works in pair with URTXN to form a complete differential signal. URTXN stands for Upstream Transmit Negative. This is the negative end of the differential signal paired with URTXP, used to send data from the current node to the upstream node. URTXN is the negative phase signal line in the differential pair, responsible for transmitting differential signals together with URTXP. DRTXP / SCK is a multiplexed pin that stands for Downstream Transmit Positive and the serial clock signal (SCK). When used as DRTXP, it is used to send the positive part of the differential signal to the downstream node. When used as SCK, it provides a clock signal for synchronous data transmission (usually used in SPI communication). DRTXN / CSN is also a multiplexed pin, representing the negative end of the differential signal sent downward (Downstream Transmit Negative) and the chip select signal (ChipSelect, Negative, CSN). When used as DRTXN, it is used to send the negative part of the differential signal to the downstream node. When used as CSN, it is used to select the slave device that communicates with the master chip (in SPI communication, when CSN is low, the selected chip is activated).

[0028] In an embodiment of the present invention, the scheme of the present invention establishes communication with the main control chip through multiple differential transceivers, each differential transceiver is set in one-to-one correspondence with the corresponding battery unit, and an independent AFE chip is integrated for collecting battery parameters. This design solves the problem of large size of isolation devices and numerous peripheral devices in traditional systems through an improved daisy chain communication method and based on the construction of DC coupling. Through DC coupling technology, the system effectively reduces the dependence on large-size isolation devices, thereby helping to achieve the miniaturization of the BMS system. At the same time, the differential transceiver transmits the collected battery parameters back to the main control chip through differential signals. This signal transmission method has strong anti-interference ability and improves the transmission integrity and reliability of the signal. In addition, each differential transceiver independently integrates an AFE chip, so that the system can collect and process battery parameters more efficiently, reduce the number of peripheral devices, and simplify the integration difficulty of the CCS pack process. Overall, the system has significant technical effects in improving communication efficiency, reducing costs and enhancing system integration.

[0029] Based on the scheme of the present invention, each differential transceiver establishes communication based on an improved daisy chain; wherein the improved daisy chain is constructed based on DC coupling. This design choice significantly improves the communication efficiency and reliability of the system, especially in a complex electromagnetic environment. The traditional daisy chain communication structure usually relies on AC coupling or transformer coupling. Although these methods can provide a certain degree of electrical isolation, they have certain limitations in terms of signal integrity and transmission efficiency. By introducing DC coupling technology, the improved daisy chain structure can directly transmit the DC component of the signal, avoiding the common high-frequency attenuation problem in AC coupling, thereby ensuring high-fidelity transmission of the signal. The introduction of DC coupling also reduces the reliance on large-size isolation devices, allowing the entire system to be designed more compactly and reducing the volume of the BMS system. In addition, DC coupling technology allows a simpler circuit structure, which not only reduces the design complexity of the system, but also reduces manufacturing costs. The improved daisy chain structure enhances the system's integration by reducing the use of traditional isolation components, making the circuit layout more flexible, and helping to cope with the growing demand for battery module management.

[0030] Furthermore, the application of DC coupling brings multiple advantages. First, it improves the transmission speed and efficiency of signals, especially in complex systems with multiple nodes in series, reducing signal delay and attenuation. Second, the DC coupling design improves the system's anti-interference ability, so that signal transmission remains stable in environments with strong electromagnetic interference. In addition, the improved daisy chain structure further optimizes the system's thermal management performance because it reduces the use of high-power isolation devices, thereby reducing the overall power consumption of the system.

[0031] Furthermore, the solution of the present invention solves the voltage, temperature, overvoltage, overcurrent and undervoltage detection problems of a single cell through a single-cell BMS chip AFE (analog front-end detection chip), which has significant advantages in system design. When an external temperature detection device is used, only one TS (temperature detection) device is required as a peripheral device, which greatly reduces the complexity of the circuit and the number of peripheral devices. If an internal temperature detection solution is selected, no external device support is required, thereby achieving the highest integration. This design not only meets the requirements for high integration in the CCS (Cells Contact System) system, but also simplifies the manufacturing and assembly process and reduces potential hardware failure points.

[0032] Based on the solution of the present invention, the dependence on external devices is reduced, making the system more compact and suitable for application in battery management systems with limited space. By reducing the number of peripheral devices, the reliability and stability of the system are improved, and the overall production cost is reduced. The application of internal temperature detection further improves the system's integration and anti-interference ability, allowing the CCS system to still operate stably in complex environments. In general, this design greatly optimizes the system's integration and reliability, and meets the needs of modern battery management systems for efficient, stable, and low-cost solutions.

[0033] Based on the scheme of the present invention, in the circuit design of a single cell, no additional peripheral devices are required to support the core functions of the BMS (battery management system). In other words, all necessary detection and control functions are integrated into the BMS chip, and a single cell can be directly connected to the BMS chip without the need for additional peripheral components such as resistors, capacitors, and diodes. This design improves the system's integration, simplifies circuit design, reduces the number of components in the bill of materials (BOM), and helps reduce costs and simplify production processes.

[0034] Furthermore, in order to ensure electrical isolation and signal transmission stability between battery packs composed of multiple cells, only a transformer is needed for isolation. Transformer isolation can effectively prevent voltage crossover and noise interference, while ensuring safe and reliable signal transmission between different battery packs. By using only transformer isolation without other complex isolation devices, the system design is simplified while maintaining good electrical isolation.

[0035] Preferably, the differential communication pins of each AFE chip are connected in series via a differential line; the differential communication signal and the single-ended signal of each AFE chip are multiplexed and transmitted on the same pin.

[0036] In an embodiment of the present invention, the differential communication pins of each AFE chip are connected in series through differential lines, and these differential communication signals and single-ended signals are multiplexed on the same pin for transmission. The core of this design is to improve the integration and efficiency of the communication link, realize DC coupling, and reduce the number of required pins. By multiplexing differential communication signals and single-ended signals on the same pin, the system achieves higher pin utilization, making the circuit design more compact and concise. This multiplexing design not only simplifies wiring and reduces the complexity of the PCB board, but also effectively reduces hardware costs.

[0037] Based on the solution of the present invention, the serial connection of the differential communication pins ensures that the data transmission between multiple AFE chips has strong anti-interference ability, especially in long distance or high noise environment. The inherent characteristics of differential signal transmission enable it to maintain high-quality signal integrity under extreme conditions and avoid signal attenuation or distortion. And by multiplexing with single-ended signals, the system's demand for physical space and pin resources is further reduced, making the entire communication link more efficient. Reusing the same pin to transmit differential and single-ended signals allows the system to flexibly switch signal modes as needed to adapt to different application scenarios. This provides higher compatibility for multiple signal requirements in complex battery management systems. At the same time, it reduces the complex operations during system switching and improves the response speed and stability of the system.

[0038] Preferably, Figure 2 Each differential transceiver includes: a downward transceiver, which is used to collect differential data of upstream / downstream nodes and transmit the corresponding differential data to the next node; a single-ended receiving module, which is used to collect single-ended signals of corresponding battery cells or upstream / downstream nodes; a wake-up module, which is used to wake up the corresponding differential transceiver when the input signal is triggered; and a calibration module, which is used to perform calibration functions in an ATE environment.

[0039] In an embodiment of the present invention, each differential transceiver includes three core modules: a downward transceiver, a single-ended receiving module, and a wake-up module. The downward transceiver is responsible for collecting differential data from upstream or downstream nodes and accurately transmitting these data to the next node. This design ensures that in the daisy chain communication structure, each node can efficiently receive and forward data to maintain the integrity and reliability of the entire communication link. Differential data transmission has excellent anti-interference ability, especially in long distance or high noise environment, which can significantly reduce the impact of signal attenuation and interference on data transmission.

[0040] Furthermore, the single-ended receiving module is mainly used to collect single-ended signals from the corresponding battery cells or upstream / downstream nodes. By supporting the collection of single-ended signals, the system can flexibly handle different types of signal inputs and adapt to a variety of application scenarios. Single-ended signals are usually used to transmit low-rate, short-distance control signals or status information, while differential signals are used for high-speed, long-distance data transmission. The introduction of the single-ended receiving module enables the system to take into account the advantages of both signal modes, retaining the simplicity of single-ended signals and utilizing the stability and anti-interference of differential signals.

[0041] Furthermore, the wake-up module plays a key role in the low-power management of the system. When triggered by an input signal, the wake-up module immediately starts the corresponding differential transceiver and puts it into operation. This design greatly improves the energy efficiency of the system, especially in the battery management system, where the wake-up module can ensure that the system consumes energy only when needed, thereby extending the battery life. Through this low-power management mechanism, the system can achieve efficient energy scheduling and management in large-scale battery packs.

[0042] Based on the solution of the present invention, the entire differential transceiver structure significantly improves the communication reliability and energy efficiency of the system. The downward transceiver ensures stable data transmission, the single-ended receiving module enhances the signal processing flexibility of the system, and the wake-up module optimizes the energy consumption of the system. The combination of these modules enables the system to work stably in a complex electromagnetic environment, while effectively reducing power consumption and extending the operating time of the device. This design is particularly suitable for modern battery management systems that have high requirements for data transmission reliability and energy efficiency.

[0043] Furthermore, the calibration module performs calibration functions in an ATE (Automated Equipment Test) environment to ensure that the chip or system can achieve optimal performance during the production and testing stages. ATE is an automated test equipment used to perform functional testing, performance evaluation, and calibration on semiconductor devices, printed circuit boards (PCBs), etc. In an ATE environment, the calibration module can accurately adjust and compensate for parameter deviations in the circuit, such as voltage, temperature, signal delay, etc., to ensure that each chip meets the design requirements before mass production.

[0044] Specifically, the calibration module can automatically detect and adjust key parameters in the circuit to ensure the performance consistency of each chip. This process usually includes automated voltage calibration, signal offset adjustment, temperature compensation and other steps to eliminate inconsistencies caused by manufacturing process differences. Through the automated calibration process, production efficiency can be greatly improved and the errors and instabilities caused by manual calibration can be reduced.

[0045] Based on the solution of the present invention, the introduction of the calibration module greatly improves the quality control and consistency of the chip. By performing automated calibration in an ATE environment, it is ensured that each produced chip can meet the expected performance indicators. This not only reduces the proportion of unqualified products, but also improves the efficiency of the entire production process and reduces production costs. In general, this calibration method provides reliable quality assurance for the large-scale production of chips, especially in application scenarios with high precision and high performance requirements, which can significantly improve the competitiveness of products.

[0046] Preferably, the downward transceiver includes a transmitter and a receiver; the transmitter is used to output a pseudo differential signal; and the receiver is used to clamp the common mode value of the comparator to a corresponding preset level when in an upward receiver or a downward receiver.

[0047] Further, such as Figure 3 The transmitter is composed of an output buffer of two inverter structures and a deep N-well MOS tube; wherein the upward transmitting end of the transmitter is a deep N-well NMOS tube; the downward transmitting end of the transmitter is a deep N-well PMOS tube; the well potentials of the deep N-well NMOS tube and the deep N-well PMOS tube are both floating.

[0048] In the embodiment of the present invention, the transmitter is composed of an output buffer of two inverter structures and a deep N-well MOS tube; wherein the upward transmitting end of the transmitter is a deep N-well NMOS tube, and the downward transmitting end is a deep N-well PMOS tube; the well potentials of the deep N-well NMOS tube and the deep N-well PMOS tube are both floating. This design significantly improves the signal transmission performance and anti-interference ability of the transmitter by optimizing the structure and potential control of semiconductor devices.

[0049] Furthermore, the output buffer of the inverter architecture provides stability of the transmission signal. The inverter provides the necessary driving capability for the transmission signal by inverting the input signal and then outputting it, so that the signal maintains a strong driving current during the transmission process, ensuring the integrity and transmission speed of the signal. By adopting two output buffers of the inverter architecture, the transmitter can effectively reduce the distortion of the output signal and improve the reliability of the overall circuit. The introduction of deep N-well NMOS tubes and PMOS tubes further enhances the performance of the transmitter. The upward transmitting end adopts a deep N-well NMOS tube, so that the circuit can still maintain stable performance under high voltage. The downward transmitting end adopts a deep N-well PMOS tube, which provides better current driving capability under low voltage. This design can optimize the output characteristics of the transmitter under different voltage conditions and ensure the reliability of the signal in various working environments.

[0050] It is particularly noteworthy that the well potentials of the deep N-well NMOS and PMOS transistors are both floating. This design choice is to reduce parasitic effects and enhance electrical isolation. The floating well potential allows these two transistors to be free from the constraints of fixed potentials when working, and can flexibly adjust their internal potentials according to changes in external signals, thereby effectively reducing the influence of parasitic capacitance. Such a design not only improves the purity of the transmitted signal, but also greatly enhances the anti-interference ability of the circuit, especially in complex electromagnetic environments, and can significantly reduce the interference of external noise on signal transmission.

[0051] Based on the scheme of the present invention, the scheme of the present invention achieves efficient signal transmission and excellent anti-interference performance by combining the advantages of the inverter output buffer and the deep N-well MOS tube. The floating well potential design further optimizes the electrical characteristics of the circuit, reduces parasitic effects, and enables the transmitter to remain stable in a high-frequency, high-voltage working environment, ensuring the overall reliability and performance of the system. This design is particularly suitable for application scenarios with high requirements for signal quality and anti-interference capabilities, such as complex communication systems and precision electronic equipment.

[0052] Preferably, Figure 4 The upward transmitting end is configured with a boost charge pump, which is used to provide a first preset amount of boost by configuring the charge pump to enable when the common mode level on the differential line is higher than the first preset value; the downward transmitting end is configured with a buck charge pump, which is used to provide a second preset amount of buck by configuring the charge pump to enable when the common mode level on the differential line is lower than the second preset value.

[0053] In the embodiment of the present invention, when the boost charge pump at the upward transmitting end detects that the common mode level on the differential signal line is higher than the first preset value, it will automatically start, and keep the signal within the appropriate voltage range by providing a 2.8V boost. The purpose of this is to avoid signal distortion and transmission instability caused by excessively high common mode levels, especially in complex electromagnetic environments. This boost mechanism can effectively enhance the signal's anti-interference ability.

[0054] At the same time, the buck charge pump configured at the downward transmitting end provides a 2.1V voltage reduction when the common mode level is lower than the second preset value to ensure that the signal does not lose transmission quality due to too low a level. The buck charge pump is used to increase the signal level to a suitable range when it is too low to ensure the symmetry and integrity of the differential signal, thereby preventing possible signal attenuation or interference during the transmission process.

[0055] Based on the scheme of the present invention, the common mode level of the differential signal is precisely controlled to ensure high-fidelity transmission of the differential signal under various conditions. The combined use of the boost and buck charge pumps not only optimizes the signal transmission path, but also reduces signal distortion caused by voltage fluctuations. Overall, this design improves the communication reliability of the system, especially in application scenarios with high requirements for signal integrity, such as complex communication networks and high-precision data transmission systems, and has significant technical advantages.

[0056] Preferably, the receiver is short-circuited with a preset value resistor; the receiver clamps the common mode value of the comparator in the receiver to a preset level through the common mode of the preset voltage to the ground; wherein, when the receiver is an upward receiver, the preset level is the preset voltage; when the receiver is a downward receiver, the preset level is the sum of the preset voltage and the system power supply voltage.

[0057] Preferably, the receiver first achieves signal matching through a 120-ohm termination resistor to ensure that the reflection of the differential signal in the line is minimized and the integrity of the signal is maintained. Next, the common-mode level of the comparator inside the receiver is clamped by a 1.2V voltage to ground. When the receiver is used as an upward receiver, the common-mode level of the comparator is clamped at 1.2V, which can provide a stable reference level to ensure accurate reception of the signal. In this configuration, the common-mode level of 1.2V is sufficient to handle most signals from downstream nodes, ensuring reliable transmission of signals in a lower voltage environment.

[0058] On the other hand, when the receiver is used as a downward receiver, the circuit's operating level needs to adapt to the higher voltage signal from the upstream node. Therefore, the preset level is set to Vbat+1.2V, which superimposes the 1.2V reference voltage on the system power supply voltage, allowing the receiver to adapt to higher signal levels and ensure that it can still stably receive signals in a high-voltage environment. This design can effectively improve the receiver's adaptability under different voltage conditions, allowing the system to flexibly respond to different signal environments.

[0059] Based on the scheme of the present invention, by introducing a preset value resistor and common mode voltage clamp in the receiver, the system significantly improves the reliability and anti-interference ability of signal transmission. Whether under high voltage or low voltage conditions, the receiver can stably receive and process signals, reducing the impact of voltage fluctuations and environmental noise on signal quality. This design is particularly suitable for use in complex communication systems with multiple nodes, ensuring stable signal processing capabilities under various operating conditions.

[0060] Figure 5 FIG. 1 is a flow chart of a daisy chain-based communication method provided by an embodiment of the present invention. Figure 5 As shown, an embodiment of the present invention provides a daisy chain-based communication method, the method comprising:

[0061] Step S10: In response to the input signal trigger, wake up the corresponding differential transceiver and determine a signal processing scheme based on the input signal.

[0062] Specifically, if the input signal is a battery parameter acquisition signal of a corresponding battery cell, the corresponding signal processing scheme is to process the acquisition signal into a corresponding transmission signal; if the input signal is an input signal of an upstream / downstream node, the corresponding signal processing scheme is a signal relay scheme.

[0063] In an embodiment of the present invention, when the input signal is a battery parameter acquisition signal corresponding to a battery cell, the signal processing scheme processes the input analog acquisition signal into a digital transmission signal for transmission through a differential transceiver. If the input signal comes from an upstream or downstream node, the system will select a signal relay scheme, that is, the received signal is processed as necessary before being passed to the next node. This flexible signal processing mechanism allows the system to dynamically adjust when processing different types of signals, thereby optimizing the signal transmission path and processing efficiency.

[0064] Step S20: Execute a corresponding signal processing scheme to process the input signal to obtain an output signal.

[0065] Specifically, the system executes the selected signal processing scheme, processes the input signal, and generates an output signal. This process includes signal amplification, filtering, digitization and other processing steps to ensure the integrity and accuracy of the signal during transmission. Through precise signal processing, the system can effectively convert the collected battery parameters into signals suitable for transmission, or optimize the transferred signals to adapt to different transmission conditions.

[0066] Step S30: determining a signal flow direction based on the output signal, and transmitting the output signal to the next section based on the corresponding signal flow direction.

[0067] Specifically, the system determines the direction of the signal based on the generated output signal, and transmits the output signal to the next node or the corresponding processing unit according to the signal direction. This step ensures that the signal can be efficiently transmitted between nodes along the predetermined path, avoiding delays or losses in signal transmission. At the same time, the high anti-interference ability of the differential transceiver enables the signal to maintain its quality and integrity during long-distance transmission.

[0068] Step S40: If no signal activity occurs within a preset time, the corresponding differential transceiver is controlled to enter a sleep mode.

[0069] Specifically, when the system does not detect any signal activity within a preset time, it will control the corresponding differential transceiver to enter sleep mode. This design greatly improves the energy efficiency of the system, automatically reduces power consumption when no signal transmission is required, and extends the service life of the device. The automatic control mechanism of the sleep mode ensures that the system can effectively save energy while maintaining high performance, and is particularly suitable for battery management systems with high energy efficiency requirements.

[0070] In an embodiment of the present invention, the scheme of the present invention significantly improves the performance of the differential transceiver and the overall communication efficiency of the system through precise signal processing and flow control. First, the system can flexibly select the signal processing scheme according to the type of input signal, ensuring the optimal processing and transmission path of different types of signals. Secondly, by performing efficient signal processing steps, the system ensures the integrity and transmission quality of the signal. In addition, the introduction of the automatic sleep mode significantly reduces the energy consumption of the system, especially when no signal activity is detected for a long time, it can effectively save energy. Overall, this design realizes efficient, flexible and low-power operation of the communication system, and is particularly suitable for battery management systems that need to frequently collect and transmit large amounts of data. Through this combination of dynamic signal processing and energy consumption management, the system not only improves work efficiency, but also extends the service life of the equipment, providing strong technical support for modern intelligent battery management.

[0071] The embodiment of the present invention further provides a computer-readable storage medium, on which instructions are stored, which, when executed on a computer, enable the computer to execute the above-mentioned daisy-chain-based communication method.

[0072] Those skilled in the art will understand that all or part of the steps in the method for implementing the above-mentioned embodiments can be completed by instructing the relevant hardware through a program, and the program is stored in a storage medium, including several instructions for making a single-chip microcomputer, a chip or a processor (processor) perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0073] The optional embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the embodiments of the present invention are not limited to the specific details in the above embodiments. Within the technical concept of the embodiments of the present invention, the technical scheme of the embodiments of the present invention can be subjected to a variety of simple modifications, and these simple modifications all belong to the protection scope of the embodiments of the present invention. It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the embodiments of the present invention will not further describe various possible combinations.

[0074] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the embodiments of the present invention, they should also be regarded as the contents disclosed in the embodiments of the present invention.

Claims

1. A daisy chain-based communication system, applied to battery module detection communication, characterized in that: The system comprises: Multiple differential transceivers are connected to the main control chip for communication, each differential transceiver is set in one-to-one correspondence with the battery cell of each battery module, and each differential transceiver establishes communication based on an improved daisy chain; wherein, The improved daisy chain is constructed based on DC coupling; Each differential transceiver integrates an independent AFE chip to perform battery parameter acquisition of the corresponding battery cell; Each differential transceiver is used to transmit the battery parameters of the corresponding battery unit back to the main control chip through a differential signal.

2. The system according to claim 1, characterized in that The differential communication pins of each AFE chip are connected in series via differential lines; The differential communication signals and single-ended signals of each AFE chip are multiplexed and transmitted on the same pin.

3. The system according to claim 1, characterized in that Each differential transceiver includes: Downward transceiver, used to collect differential data from upstream / downstream nodes and transmit the corresponding differential data to the next node; A single-ended receiving module is used to collect single-ended signals of corresponding battery cells or upstream / downstream nodes; A wake-up module, used to wake up the corresponding differential transceiver when triggered by an input signal; The calibration module is used to perform calibration functions in an ATE environment.

4. The system according to claim 3, characterized in that The downward transceiver includes a transmitter and a receiver; The transmitter is used to output a pseudo differential signal; The receiver is used to clamp the comparator common mode value to a corresponding preset level when in an upward receiver or a downward receiver.

5. The system according to claim 4, characterized in that The transmitter is composed of two inverter-structured output buffers and a deep N-well MOS tube; wherein, The upward transmitting end of the transmitter is a deep N-well NMOS tube; The downward transmitting end of the transmitter is a deep N-well PMOS tube; The well potentials of the deep N-well NMOS tube and the deep N-well PMOS tube are both floating.

6. The system according to claim 5, characterized in that The upward transmitting end is configured with a boost charge pump, which is used to provide a first preset amount of boost by enabling the charge pump when the common mode level on the differential line is higher than a first preset value; The downward transmitting end is configured with a step-down charge pump, which is used to provide a second preset amount of voltage reduction by enabling the charge pump when the common mode level on the differential line is lower than a second preset value.

7. The system according to claim 4, characterized in that The receiver is short-circuited with a resistor of a preset value; The receiver clamps the common mode value of the comparator in the receiver to a preset level through the common mode of the preset voltage to the ground; wherein, When the receiver is an upward receiver, the preset level is a preset voltage; When the receiver is a downward receiver, the preset level is the sum of the preset voltage and the system power supply voltage.

8. A daisy chain-based communication method, applied to battery module detection communication, characterized in that: The method is implemented based on the daisy chain-based communication system according to any one of claims 1 to 7, and the method comprises: In response to an input signal trigger, waking up a corresponding differential transceiver, and determining a signal processing scheme based on the input signal; Execute a corresponding signal processing scheme to process the input signal to obtain an output signal; determining a signal flow direction based on the output signal, and transmitting the output signal to a next node based on the corresponding signal flow direction; If no signal activity occurs within a preset time, the corresponding differential transceiver is controlled to enter a sleep mode.

9. The method according to claim 8, characterized in that The step of determining a signal processing scheme based on an input signal comprises: If the input signal is a battery parameter acquisition signal of a corresponding battery unit, the corresponding signal processing scheme is to process the acquisition signal into a corresponding transmission signal; If the input signal is an input signal of an upstream / downstream node, the corresponding signal processing scheme is a signal relay scheme.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores instructions, which, when executed on a computer, enable the computer to execute the daisy chain-based communication method as described in any one of claims 8 or 9.

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