Circuit compatible with two types of CAN transceivers

Abstract

The invention discloses a circuit compatible with two types of CAN transceivers, and relates to the technical field of CAN transceiver circuits, a plurality of patch packaging pins are arranged on a substrate of the circuit of the CAN transceivers, a CAN communication interface and a filter circuit are arranged on the substrate, a local wake-up circuit and a resistor are arranged on the substrate, and the local wake-up circuit and the resistor are arranged on the substrate. When one type of CAN transceiver is arranged on the substrate and connected with part of the patch packaging pins, the CAN communication interface and filter circuit and part of the resistors are connected with the CAN transceiver, and when the other type of CAN transceiver is arranged on the substrate and connected with part of the patch packaging pins, the CAN communication interface and filter circuit, the local wake-up circuit and part of the resistors are connected with the CAN transceiver. The CAN transceiver with the local wake-up function is connected with the local wake-up circuit, so that dormancy or wake-up of the control system is realized, when the CAN transceiver without the local wake-up function is used, the local wake-up circuit is not welded, the substrate does not need to be integrally replaced when different types of CAN transceivers are replaced, and the manufacturing cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of CAN transceiver circuits, and in particular to a circuit compatible with two types of CAN transceivers. Background Art

[0002] At present, automotive electronic products and systems are becoming increasingly complex and have powerful integrated functions. They basically have CAN bus communication functions. The CAN transceivers used are widely used SOP8 packaged 1042 type transceivers. The emerging SOP14 packaged 1043 transceivers add the local wake-up function of automotive electronic products on the basis of the 1042 type transceivers. The commonality of the two types of CAN transceivers is that they both have sleep and remote wake-up functions. The SOP14 packaged 1043 transceiver can control the power off and on through the local wake-up function, which is more helpful to reduce the control of the system's static dark current. However, there are differences in the pin definition, function definition and package definition of the two CAN transceivers.

[0003] The prior art is to use a 1042 type CAN transceiver in SOP8 package. However, it is difficult for the CAN transceiver to realize local wake-up through the module itself, and when using a CAN transceiver with local wake-up function, the substrate needs to be replaced as a whole, which increases the manufacturing cost. Summary of the invention

[0004] An embodiment of the present invention provides a circuit compatible with two types of CAN transceivers to solve the technical problem that the existing CAN transceiver in the related art is difficult to realize local wake-up through the module itself, and when using a CAN transceiver with a local wake-up function, the substrate needs to be replaced as a whole, which increases the production cost.

[0005] An embodiment of the present invention provides a circuit compatible with two types of CAN transceivers, including:

[0006] A substrate, on which a plurality of surface mount package pins are arranged;

[0007] A CAN communication interface and a filter circuit, wherein the CAN communication interface and the filter circuit are arranged on the substrate;

[0008] A local wake-up circuit, wherein the local wake-up circuit is arranged on the substrate;

[0009] a plurality of resistors, wherein the plurality of resistors are disposed on the substrate; and

[0010] When one type of CAN transceiver is arranged on the substrate and connected to some of the chip package pins, the CAN communication interface and filtering circuit and some of the resistors are connected to the CAN transceiver; when another type of CAN transceiver is arranged on the substrate and connected to some of the chip package pins, the CAN communication interface and filtering circuit, the local wake-up circuit and some of the resistors are connected to the CAN transceiver.

[0011] In some embodiments, the local wake-up circuit includes:

[0012] a seventh resistor R7, wherein a first end of the seventh resistor R7 is connected to a power supply and a pin of a type of CAN transceiver, and a second end of the seventh resistor R7 is connected to another pin of the type of CAN transceiver;

[0013] A transistor Q1, wherein the collector of the transistor Q1 is connected to the second end of the seventh resistor R7 and another pin of the CAN transceiver, and the emitter of the transistor Q1 is grounded;

[0014] a sixth resistor R6, wherein a first end of the sixth resistor R6 is connected to the base of the transistor Q1, and a second end of the sixth resistor R6 is grounded;

[0015] A third capacitor C3, a first end of the third capacitor C3 is connected to the first end of the sixth resistor R6, and a second end of the third capacitor C3 is grounded;

[0016] A fifth resistor R5, a first end of the fifth resistor R5 is connected to the first end of the sixth resistor R6 and the base of the transistor Q1, and a second end of the fifth resistor R5 is connected to the controller.

[0017] In some embodiments, the local wake-up circuit further includes:

[0018] a fourth capacitor C4, wherein a first end of the fourth capacitor C4 is connected to a power source and a first end of the seventh resistor R7, and a second end of the fourth capacitor C4 is grounded;

[0019] A fifth capacitor C5, a first end of the fifth capacitor C5 is connected to a power source and a first end of the seventh resistor R7, and a second end of the fifth capacitor C5 is grounded.

[0020] In some embodiments, the plurality of resistors include an eighth resistor R8, a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11, and a twelfth resistor R12.

[0021] In some embodiments, when a type of CAN transceiver is TJA1042T, the CAN communication interface and filter circuit, the eleventh resistor R11, the eighth resistor R8 and the twelfth capacitor C12 are connected to the type of CAN transceiver.

[0022] In some embodiments, when a type of CAN transceiver is TJA1043T, the CAN communication interface and filtering circuit, the local wake-up circuit, the ninth resistor R9, the tenth resistor R10, the twelfth resistor R12 and the eighth capacitor C8 are connected to the type of CAN transceiver.

[0023] In some embodiments, the CAN communication interface and filtering circuit include:

[0024] an eleventh capacitor C11, wherein a first end of the eleventh capacitor C11 is connected to a pin of a type of CAN transceiver, and a second end of the eleventh capacitor C11 is connected to another pin of the type of CAN transceiver;

[0025] a first inductor L1, wherein a first end of the first inductor L1 is connected to a first end of the eleventh capacitor C11, and a second end of the first inductor L1 is connected to a second end of the eleventh capacitor C11;

[0026] A tenth capacitor C10 , wherein a first end of the tenth capacitor C10 is connected to a first end of the first inductor L1 , and a second end of the tenth capacitor C10 is connected to a second end of the first inductor L1 .

[0027] In some embodiments, the CAN communication interface and filtering circuit further includes:

[0028] a thirteenth resistor R13, a first end of the thirteenth resistor R13 being connected to a first end of the tenth capacitor C10;

[0029] a fourteenth resistor R14, wherein a first end of the fourteenth resistor R14 is connected to a second end of the thirteenth resistor R13, and a second end of the fourteenth resistor R14 is connected to a second end of the tenth capacitor C10;

[0030] A ninth capacitor C9, wherein a first end of the ninth capacitor C9 is connected to a first end of the fourteenth resistor R14 and a second end of the thirteenth resistor R13, and a second end of the ninth capacitor C9 is grounded.

[0031] In some embodiments, the CAN communication interface and filtering circuit further includes:

[0032] a sixth capacitor C6, wherein a first end of the sixth capacitor C6 is connected to a first end of the thirteenth resistor R13, and a second end of the sixth capacitor C6 is grounded;

[0033] a seventh capacitor C7, wherein a first end of the seventh capacitor C7 is connected to a second end of the sixth capacitor C6, and a second end of the seventh capacitor C7 is connected to a second end of the fourteenth resistor R14;

[0034] The electrostatic diode ESD1 has a first end connected to the second end of the seventh capacitor C7, a second end connected to the first end of the sixth capacitor C6, and a third end connected to the second end of the sixth capacitor C6.

[0035] In some embodiments, the circuit compatible with two types of CAN transceivers further includes:

[0036] A first capacitor C1 and a second capacitor C2, wherein the first capacitor C1 and the second capacitor C2 are respectively connected to a CAN transceiver.

[0037] The beneficial effects brought about by the technical solution provided by the present invention include:

[0038] An embodiment of the present invention provides a circuit compatible with two types of CAN transceivers, including a substrate, an interface and filtering circuit for CAN communication, a local wake-up circuit and multiple resistors, wherein the substrate is provided with multiple surface mount package pins, the interface and filtering circuit for CAN communication are arranged on the substrate, the local wake-up circuit is arranged on the substrate, and multiple resistors are arranged on the substrate; when one type of CAN transceiver is arranged on the substrate and connected to some surface mount package pins, the interface and filtering circuit for CAN communication and some of the resistors are connected to the CAN transceiver; when another type of CAN transceiver is arranged on the substrate and connected to some surface mount package pins, the interface and filtering circuit for CAN communication, the local wake-up circuit and some of the resistors are connected to the CAN transceiver; by connecting a CAN transceiver with a local wake-up function to the local wake-up circuit, the control system is put into sleep or wake-up; when a CAN transceiver without a local wake-up function is used, the local wake-up circuit is not welded; when different types of CAN transceivers are replaced, there is no need to re-make the board and replace the substrate as a whole, thereby reducing the manufacturing cost and greatly shortening the development and device preparation cycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0040] Figure 1 A circuit schematic diagram of a device compatible with two types of CAN transceivers provided in an embodiment of the present invention;

[0041] Figure 2 The circuit schematic diagram of the CAN transceiver provided in the embodiment of the present invention is TJA1042T;

[0042] Figure 3 The CAN transceiver provided in the embodiment of the present invention is a circuit schematic diagram of TJA1043T. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0044] An embodiment of the present invention provides a circuit compatible with two types of CAN transceivers, which can solve the technical problem in the related art that the existing CAN transceiver is difficult to realize local wake-up through the module itself, and when using a CAN transceiver with a local wake-up function, the substrate needs to be replaced as a whole, which increases the production cost.

[0045] Figure 1 The invention provides a circuit compatible with two types of CAN transceivers, including a substrate, a CAN communication interface and a filter circuit, a local wake-up circuit and multiple resistors.

[0046] The substrate is provided with a plurality of surface mount packaging pins, the CAN communication interface and filtering circuit are provided on the substrate, the local wake-up circuit is provided on the substrate, and a plurality of resistors are provided on the substrate, and when a type of CAN transceiver is provided on the substrate and connected to some surface mount packaging pins, the CAN communication interface and filtering circuit and some of the resistors are connected to the CAN transceiver; when another type of CAN transceiver is provided on the substrate and connected to some surface mount packaging pins, the CAN communication interface and filtering circuit, the local wake-up circuit and some of the resistors are connected to the CAN transceiver.

[0047] The circuit compatible with two types of CAN transceivers provided by an embodiment of the present invention is provided with a substrate, an interface and a filtering circuit for CAN communication, a local wake-up circuit and a plurality of resistors, the substrate is provided with 14 SMD package pins, the substrate is also provided with a filter element pad, a local wake-up original pad, and a plurality of resistor welding feet, when a 1042 type CAN transceiver of SOP8 package is arranged on the substrate and connected to part of the SMD package pins, the interface and the filtering circuit of the CAN communication are connected to the filter element pad, part of the resistors are connected to the resistor welding feet, and the interface and the filtering circuit of the CAN communication and part of the resistors are also connected to the CAN transceiver; when a 1043 type CAN transceiver of SOP14 ... and part of the resistors are connected to the CAN transceiver; when a 1043 type When the CAN transceiver is arranged on the substrate and connected to some of the surface mount package pins, the interface and filtering circuit of the CAN communication are connected to the filter element pad, the local wake-up circuit is connected to the local wake-up original pad, and some of the resistors are connected to the resistor welding feet. The interface and filtering circuit of the CAN communication, the local wake-up circuit and some of the resistors are also connected to the CAN transceiver. By connecting the CAN transceiver with a local wake-up function to the local wake-up circuit, the control system can be put into sleep or wake-up. When a CAN transceiver without a local wake-up function is used, the local wake-up circuit is not welded. When replacing different types of CAN transceivers, there is no need to replace the substrate as a whole, thereby reducing the production cost.

[0048] As an optional embodiment, in one embodiment of the invention, see Figure 1As shown, the local wake-up circuit includes: a seventh resistor R7, a transistor Q1, a sixth resistor R6, a third capacitor C3 and a fifth resistor R5, the seventh resistor R7 is a pull-up resistor, the first end of the seventh resistor R7 is connected to the 10# pin of the 14-pin CAN transceiver, and is also connected to the external vehicle power supply BAT+, the other end of the seventh resistor R7 is connected to the 9# pin of the 14-pin CAN transceiver, the collector of the transistor Q1 is connected to the second end of the seventh resistor R7 and the 9# pin of the 14-pin CAN transceiver, and the 9# pin of the CAN transceiver is the input Wake of the local wake-up state The first end of the sixth resistor R6 is connected to the base of the transistor Q1, the second end of the sixth resistor R6 is grounded, the first end of the third capacitor C3 is connected to the first end of the sixth resistor R6, the second end of the third capacitor C3 is grounded, the first end of the fifth resistor R5 is connected to the first end of the sixth resistor R6 and the base of the transistor Q1, the second end of the fifth resistor R5 is connected to the controller, and when the vehicle ignition key or one-button start is powered on, the main controller MCU sends a wake-up high-level signal to Local Wake-n, the wake-up high-level signal is output to the base of the transistor Q1 through the voltage divider and filter circuit composed of the fifth resistor R5, the sixth resistor R6, and the third capacitor C3, to control the transistor Q1 to be turned on or off. When the transistor Q1 is turned on, the level of the 9# pin of the CAN transceiver changes and is awakened to work. The 10# pin of the CAN transceiver is always powered by the power supply BAT+, ensuring that the CAN transceiver can always work in the background, including realizing local or remote wake-up functions during sleep.

[0049] As an optional embodiment, in one embodiment of the invention, see Figure 1 As shown, the local wake-up circuit also includes: a fourth capacitor C4 and a fifth capacitor C5, the first end of the fourth capacitor C4 is connected to the power supply and the first end of the seventh resistor R7, the second end of the fourth capacitor C4 is grounded, the first end of the fifth capacitor C5 is connected to the power supply and the first end of the seventh resistor R7, the second end of the fifth capacitor C5 is grounded, the fourth capacitor C4 and the fifth capacitor C5 are both filter capacitors, which are used to reduce the AC ripple coefficient of the power supply BAT+, provide a path for high-frequency signals, reduce the internal resistance of the power supply, and improve efficient and smooth DC output.

[0050] As an optional embodiment, in one embodiment of the invention, see Figure 1As shown, the multiple resistors include an eighth resistor R8, a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11, and a twelfth resistor R12, the eighth resistor R8 is a pull-up resistor, the ninth resistor R9 is a pull-down resistor, the tenth resistor R10, the eleventh resistor R11, and the twelfth resistor R12 are all zero-ohm resistors, and the pull-up resistors or the pull-down resistors or the zero-ohm resistors are selectively welded and connected to a type of CAN transceiver, so that the substrate does not need to be replaced when the CAN transceiver is replaced.

[0051] As an optional embodiment, in one embodiment of the invention, see Figure 2 As shown, when a type of CAN transceiver is TJA1042T, the CAN communication interface and filter circuit, the eleventh resistor R11, the eighth resistor R8 and the twelfth capacitor C12 are connected to the type of CAN transceiver, and the CAN communication interface and filter circuit are respectively connected to the 6# and 7# pins of the CAN transceiver TJA1042T, that is, the 12# and 13# pins on the substrate, and the 6# and 7# pins of the CAN transceiver TJA1042T are the vehicle CAN bus signals CAN nH and CAN nL is used to realize the transmission and reception of external CAN data. The eleventh resistor R11 is connected to the 5# pin of the CAN transceiver TJA1042T, that is, the 11# pin on the substrate. One end of the twelfth capacitor C12 is connected to the eleventh resistor R11, and the other end is connected to the interface and filtering circuit of the CAN communication. The 5# pin of the CAN transceiver TJA1042T is defined as the VIO function, that is, the level conversion of the CAN transceiver I / O. The operating voltage of the main controller MCU is different from that of the CAN transceiver. The eleventh resistor R11 of the zero-ohm resistor is connected to V+_MCU for conversion and matching, and the twelfth capacitor C12 is used to filter V+_MCU to remove interference; the eighth resistor R8 is connected to C The 8# pin of the AN transceiver TJA1042T is connected to the 14# pin on the substrate, and the other ends of the eleventh resistor R11 and the eighth resistor R8 are connected to the working power supply V+_MCU of the main controller MCU. The 8# pin of the CAN transceiver TJA1042T is STB, which selects the high-speed mode and the standby mode. The high level is used for selection during wake-up and normal operation. The 8# pin of the CAN transceiver TJA1042T is connected to V+_MCU through the pull-up resistor eighth resistor R8, and the high-speed mode or the standby mode is selected by outputting a high level through the main controller MCU. In addition, the CAN transceiver can also be of the type of SIT1042, NCA1042, CA-IF1042, etc.

[0052] As an optional embodiment, in one embodiment of the invention, see Figure 3As shown, when a type of CAN transceiver is TJA1043T, the CAN communication interface and filter circuit, the local wake-up circuit, the ninth resistor R9, the tenth resistor R10, the twelfth resistor R12 and the eighth capacitor C8 are connected to the type of CAN transceiver, the CAN communication interface and filter circuit are connected to the 12# and 13# pins of the CAN transceiver TJA1043T, and the 12# and 13# pins of the CAN transceiver TJA1043T are the vehicle CAN bus signal CAN nH and CAN nL is used to realize the transmission and reception of external CAN data, the local wake-up circuit is connected to the 9# and 10# pins of the CAN transceiver TJA1043T, one end of the ninth resistor R9 is connected to the 14# pin of the CAN transceiver TJA1043T, and the other end is grounded. The 14# pin of the CAN transceiver TJA1043T is STB, that is, the high-speed mode and the standby mode are selected. The low level is used for selection during wake-up and normal operation, and the 14# pin of the CAN transceiver TJA1043T is grounded through the pull-down resistor ninth resistor R9, and the high-speed mode or the standby mode is selected by the low level of grounding; one end of the tenth resistor R10 is connected to the 5# pin of the CAN transceiver TJA1043T, and the other end is connected to the working power supply V+_MCU of the main controller MCU, and one end of the twelfth resistor R12 is connected to the 1# pin of the CAN transceiver TJA1043T. 1# pin is connected, and the other end is connected to the interface and filtering circuit of the CAN communication. One end of the eighth capacitor C8 is connected to the tenth resistor R10, and the other end is grounded. The 11# pin of the CAN transceiver TJA1043T is defined as the SPLIT function, that is, the bus common mode stable output terminal, and its typical value is 0.5VCC=2.5V. The interface and filtering circuit of the CAN communication are connected through the twelfth resistor R12 to achieve a stable bus voltage of 0.5VCC=2.5V when the bus is idle. The working voltage of the main controller MCU is different from that of the CAN transceiver. It is necessary to connect V+_MCU through the zero-ohm resistor tenth resistor R10 for conversion and matching, and the V+_MCU is filtered and removed by the eighth capacitor C8 to remove interference. In addition, the CAN transceiver can also be of SIT1043, NCA1043, CA-IF1043 and other types.

[0053] As an optional embodiment, in one embodiment of the invention, see Figure 1As shown, the interface and filtering circuit of the CAN communication includes: an eleventh capacitor C11, a first inductor L1 and a tenth capacitor C10, the first end of the eleventh capacitor C11 is connected to a pin of a type of CAN transceiver, the second end of the eleventh capacitor C11 is connected to another pin of the type of CAN transceiver, the first end of the first inductor L1 is connected to the first end of the eleventh capacitor C11, the second end of the first inductor L1 is connected to the second end of the eleventh capacitor C11, the first end of the tenth capacitor C10 is connected to the first end of the first inductor L1, and the first end of the tenth capacitor C10 is connected to the first end of the first inductor L1. The second end of the tenth capacitor C10 is connected to the second end of the first inductor L1, the eleventh capacitor C11 and the tenth capacitor C10 are differential mode filter capacitors, the first inductor L1 is a common mode choke, the eleventh capacitor C11, the tenth capacitor C10 and the first inductor L1 form a double π-type filter circuit, which is connected to the 6# and 7# pins of the CAN transceiver TJA1042T or the 12# and 13# pins of the CAN transceiver TJA1043T to filter external CAN data, filter out differential mode interference, reduce interference and noise, and reduce the impact of external interference on the circuit.

[0054] As an optional embodiment, in one embodiment of the invention, see Figure 1 As shown, the CAN communication interface and filter circuit also includes: a thirteenth resistor R13, a fourteenth resistor R14 and a ninth capacitor C9, the first end of the thirteenth resistor R13 is connected to the first end of the tenth capacitor C10, the first end of the fourteenth resistor R14 is connected to the second end of the thirteenth resistor R13, the second end of the fourteenth resistor R14 is connected to the second end of the tenth capacitor C10, the first end of the ninth capacitor C9 is connected to the first end of the fourteenth resistor R14 and the second end of the thirteenth resistor R13 The second end of the ninth capacitor C9 is grounded, the midpoint of the thirteenth resistor R13 and the fourteenth resistor R14 is connected to the ninth capacitor C9 to form a T-type RC filter circuit, which is used to eliminate the high-frequency components in the signal so that the output signal is closer to the low-frequency part of the original signal, and the 11# pin of the CAN transceiver TJA1043T is connected to the midpoint of the thirteenth resistor R13 and the fourteenth resistor R14 through the twelfth resistor R12 to achieve a stable bus voltage of 0.5VCC=2.5V when the bus is idle.

[0055] As an optional embodiment, in one embodiment of the invention, see Figure 1As shown, the interface and filtering circuit of the CAN communication also include: a sixth capacitor C6, a seventh capacitor C7 and an electrostatic diode ESD1, the first end of the sixth capacitor C6 is connected to the first end of the thirteenth resistor R13, the second end of the sixth capacitor C6 is grounded, the first end of the seventh capacitor C7 is connected to the second end of the sixth capacitor C6, the second end of the seventh capacitor C7 is connected to the second end of the fourteenth resistor R14, the first end of the electrostatic diode ESD1 is connected to the second end of the seventh capacitor C7, the second end of the electrostatic diode ESD1 is connected to the first end of the sixth capacitor C6, the third end of the electrostatic diode ESD1 is connected to the second end of the sixth capacitor C6, the sixth capacitor C6 and the seventh capacitor C7 are common-mode filter capacitors for filtering out common-mode interference of external CAN data, and the electrostatic diode ESD1 is used for anti-static, protecting electronic circuits from the influence of electrostatic discharge, thereby achieving the function of protecting circuits.

[0056] As an optional embodiment, in one embodiment of the invention, see Figure 1 As shown, the circuit compatible with two types of CAN transceivers also includes: a first capacitor C1 and a second capacitor C2, the first capacitor C1 and the second capacitor C2 are respectively connected to a type of CAN transceiver, one end of the first capacitor C1 is connected to the VCC end of the CAN transceiver TJA1042T or the CAN transceiver TJA1043T, the other end of the first capacitor C1 is connected to the GND end of the CAN transceiver TJA1042T or the CAN transceiver TJA1043T, one end of the second capacitor C2 is also connected to the VCC end of the CAN transceiver TJA1042T or the CAN transceiver TJA1043T, and the other end of the second capacitor C2 is also connected to the GND end of the CAN transceiver TJA104 2T or the GND end of the CAN transceiver TJA1043T, the VCC end of the CAN transceiver TJA1042T or the CAN transceiver TJA1043T is connected to the external 5V power supply, the first capacitor C1 and the second capacitor C2 are filter capacitors at the power supply end, which provide a path for the high-frequency signal and reduce the internal resistance of the power supply; the 1# pin of the CAN transceiver TJA1042T or the CAN transceiver TJA1043T is connected to the main controller MCU through a small-resistance current-limiting resistor R1, and the 4# pin of the CAN transceiver TJA1042T or the CAN transceiver TJA1043T is connected to the main controller MCU through a small-resistance current-limiting resistor R2, so as to realize the sending and receiving of CAN messages between the two, CAN n-Tx is sent by the MCU and received by the CAN transceiver; CAN n-Rx is received by the MCU and sent by the CAN transceiver.

[0057] Specifically, see Figure 3As shown in the figure, the 6# pin of the CAN transceiver TJA1043T is defined as the output enable EN. The 6# pin of the CAN transceiver TJA1043T is connected to the system power supply VCC, that is, the 5V power supply, through the pull-up resistor R3, and is also connected to the electrical network CAN n-EN of the main controller MCU. This pin outputs the corresponding high and low level states according to the requirements of different modes such as normal operation, mute, standby, sleep waiting, and sleep, and cooperates with STB; the 7# pin of the CAN transceiver TJA1043T is defined as the control system power on INH output, that is, the pin is pulled high during local, remote wake-up, and normal operation, and the pin is in high impedance state during pre-sleep or sleep, so as to realize the system output control of the system power after the vehicle input power is stepped down and converted. When receiving a local or remote wake-up command and the system is working normally, the 7# pin of the CAN transceiver TJA1043T outputs a high level. The system controls the output of the system power after the vehicle input power is stepped down and converted, so as to realize system wake-up and normal operation. When the system needs to sleep, the 7# pin of the CAN transceiver TJA1043T outputs a low level to turn off the system power and control it with a very small static current. The 8# pin of the CAN transceiver TJA1043T is defined as the error monitoring indication output ERRN, which is connected to the MCU's working power supply V+_MCU through the pull-up resistor R4, and outputs corresponding high and low levels according to different modes such as normal operation, mute, standby, sleep waiting, sleep, etc. and the status of the bus signal.

[0058] In the description of the present invention, it should be noted that the terms "upper", "lower", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as a limitation on the present invention. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0059] It should be noted that, in the present invention, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0060] The above description is only a specific embodiment of the present invention, so that those skilled in the art can understand or implement the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but should conform to the widest scope consistent with the principles and novel features of the present invention.

Claims

1. A circuit compatible with two types of CAN transceivers, characterized in that: include: A substrate, on which a plurality of surface mount package pins are arranged; A CAN communication interface and a filter circuit, wherein the CAN communication interface and the filter circuit are arranged on the substrate; A local wake-up circuit, wherein the local wake-up circuit is arranged on the substrate; A plurality of resistors, wherein the plurality of resistors are disposed on the substrate; as well as When one type of CAN transceiver is arranged on the substrate and connected to some of the chip package pins, the CAN communication interface and filtering circuit and some of the resistors are connected to the CAN transceiver; when another type of CAN transceiver is arranged on the substrate and connected to some of the chip package pins, the CAN communication interface and filtering circuit, the local wake-up circuit and some of the resistors are connected to the CAN transceiver.

2. The circuit compatible with two types of CAN transceivers according to claim 1, characterized in that: The local wake-up circuit comprises: a seventh resistor R7, wherein a first end of the seventh resistor R7 is connected to a power supply and a pin of a type of CAN transceiver, and a second end of the seventh resistor R7 is connected to another pin of the type of CAN transceiver; A transistor Q1, wherein the collector of the transistor Q1 is connected to the second end of the seventh resistor R7 and another pin of the CAN transceiver, and the emitter of the transistor Q1 is grounded; a sixth resistor R6, wherein a first end of the sixth resistor R6 is connected to the base of the transistor Q1, and a second end of the sixth resistor R6 is grounded; A third capacitor C3, a first end of the third capacitor C3 is connected to the first end of the sixth resistor R6, and a second end of the third capacitor C3 is grounded; A fifth resistor R5, a first end of the fifth resistor R5 is connected to the first end of the sixth resistor R6 and the base of the transistor Q1, and a second end of the fifth resistor R5 is connected to the controller.

3. The circuit compatible with two types of CAN transceivers according to claim 2, characterized in that: The local wake-up circuit also includes: a fourth capacitor C4, wherein a first end of the fourth capacitor C4 is connected to a power source and a first end of the seventh resistor R7, and a second end of the fourth capacitor C4 is grounded; A fifth capacitor C5, a first end of the fifth capacitor C5 is connected to a power source and a first end of the seventh resistor R7, and a second end of the fifth capacitor C5 is grounded.

4. The circuit compatible with two types of CAN transceivers according to claim 1, characterized in that: The plurality of resistors include an eighth resistor R8 , a ninth resistor R9 , a tenth resistor R10 , an eleventh resistor R11 , and a twelfth resistor R12 .

5. The circuit compatible with two types of CAN transceivers according to claim 4, characterized in that: When a type of CAN transceiver is TJA1042T, the CAN communication interface and filter circuit, the eleventh resistor R11, the eighth resistor R8 and the twelfth capacitor C12 are connected to the type of CAN transceiver.

6. The circuit compatible with two types of CAN transceivers according to claim 5, characterized in that: When a type of CAN transceiver is TJA1043T, the CAN communication interface and filter circuit, the local wake-up circuit, the ninth resistor R9, the tenth resistor R10, the twelfth resistor R12 and the eighth capacitor C8 are connected to the type of CAN transceiver.

7. The circuit compatible with two types of CAN transceivers according to claim 1, characterized in that: The CAN communication interface and filter circuit include: an eleventh capacitor C11, wherein a first end of the eleventh capacitor C11 is connected to a pin of a type of CAN transceiver, and a second end of the eleventh capacitor C11 is connected to another pin of the type of CAN transceiver; a first inductor L1, wherein a first end of the first inductor L1 is connected to a first end of the eleventh capacitor C11, and a second end of the first inductor L1 is connected to a second end of the eleventh capacitor C11; A tenth capacitor C10 , wherein a first end of the tenth capacitor C10 is connected to a first end of the first inductor L1 , and a second end of the tenth capacitor C10 is connected to a second end of the first inductor L1 .

8. The circuit compatible with two types of CAN transceivers according to claim 7, characterized in that: The CAN communication interface and filter circuit also include: a thirteenth resistor R13, a first end of the thirteenth resistor R13 being connected to a first end of the tenth capacitor C10; a fourteenth resistor R14, wherein a first end of the fourteenth resistor R14 is connected to a second end of the thirteenth resistor R13, and a second end of the fourteenth resistor R14 is connected to a second end of the tenth capacitor C10; A ninth capacitor C9, wherein a first end of the ninth capacitor C9 is connected to a first end of the fourteenth resistor R14 and a second end of the thirteenth resistor R13, and a second end of the ninth capacitor C9 is grounded.

9. The circuit compatible with two types of CAN transceivers according to claim 8, characterized in that: The CAN communication interface and filter circuit also include: a sixth capacitor C6, wherein a first end of the sixth capacitor C6 is connected to a first end of the thirteenth resistor R13, and a second end of the sixth capacitor C6 is grounded; a seventh capacitor C7, wherein a first end of the seventh capacitor C7 is connected to a second end of the sixth capacitor C6, and a second end of the seventh capacitor C7 is connected to a second end of the fourteenth resistor R14; The electrostatic diode ESD1 has a first end connected to the second end of the seventh capacitor C7, a second end connected to the first end of the sixth capacitor C6, and a third end connected to the second end of the sixth capacitor C6.

10. The circuit compatible with two types of CAN transceivers according to claim 1, characterized in that: Also includes: A first capacitor C1 and a second capacitor C2, wherein the first capacitor C1 and the second capacitor C2 are respectively connected to a CAN transceiver.

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