Vehicle-mounted ECU low-power-consumption dormancy wake-up circuit and vehicle-mounted ECU system

Abstract

The utility model discloses a vehicle-mounted ECU low-power-consumption dormancy wake-up circuit and a vehicle-mounted ECU system. The circuit comprises a CAN transceiver, a first DC voltage stabilizing circuit, a second DC voltage stabilizing circuit and a microprocessor. The first direct-current voltage stabilizing circuit is powered by the starting battery and outputs a first power supply; the second DC voltage stabilizing circuit is powered by the first power supply and outputs a second power supply; the CAN transceiver is a CAN transceiver with a specific frame awakening function, and a first power supply pin of the CAN transceiver is connected with the starting battery; a second power supply pin of the first DC voltage stabilizing circuit is connected with a second power supply, an SPI interface and a CAN data interface of the first DC voltage stabilizing circuit are respectively connected with an SPI interface and a CAN controller of the microprocessor, a CAN bus interface of the first DC voltage stabilizing circuit is connected with a vehicle-mounted CAN bus, and an INH pin of the first DC voltage stabilizing circuit is connected with an enabling end of the first DC voltage stabilizing circuit; after voltage reduction, the ignition wake-up signal is connected with a wake-up pin of the CAN transceiver and an IO port of the microprocessor; the microprocessor is powered by a second power supply. The circuit is easy to implement, low in cost and high in reliability, and waste of a vehicle-mounted storage battery power supply is avoided.

Description

Technical Field

[0001] The utility model relates to the field of electronic technology, in particular to a low-power sleep wake-up circuit for vehicle-mounted ECU and a vehicle-mounted ECU system. Background Art

[0002] New energy electric vehicles are becoming more and more popular, and there are more and more vehicle-mounted controllers. The low-voltage power supply system of new energy electric vehicles is generally a 12V battery or a 24V battery. The 12V or 24V battery provides power for the vehicle-mounted electronic control unit. If the vehicle is stationary and not in use, the vehicle-mounted electronic control unit cannot enter the sleep state without the low-power function and remains in the high-power working state, wasting electric energy, which will cause the low-voltage battery to run out of power and lead to the vehicle being unable to start when starting the vehicle.

[0003] Patent CN212500003U provides a sleep wake-up circuit, which performs NAND processing on the AC / DC charging enable signal through a NAND gate chip, outputs the level after NAND processing to the wake-up input pin of the CAN transceiver chip, and outputs the main power wake-up signal, so that the main power provides electric energy for the power-consuming module, realizing the wake-up control of the main power of the electric vehicle. This patent mainly realizes the wake-up function of the main power of the electric vehicle and does not consider power consumption reduction.

[0004] Patent CN103605420B uses two single-chip microcomputers to achieve low-power processing, which greatly increases the complexity and cost of the system.

[0005] Patent CN 212267388U judges the NAND gate circuit of the KL15 ignition wake-up signal, the signal of the CAN wake-up module, the RTC wake-up signal, the motion detection wake-up signal, and the battery low-level wake-up signal, and uses a trigger to control the power supply. This method can realize the wake-up of the power supply. Too many wake-up source processing circuits lead to a sharp increase in the cost of the entire controller. At the same time, this patent only realizes the wake-up function and does not reflect the method of entering the low-power state.

[0006] The current methods for realizing low power consumption in sleep wake-up usually require an additional device, such as adding another single-chip microcomputer for monitoring, or making the single-chip microcomputer itself enter the sleep mode. In this mode, some peripherals of the single-chip microcomputer are still in the working state and consume energy. These two methods actually do not really achieve the purpose of low power consumption. Utility Model Content

[0007] The present utility model aims to provide a low-power sleep and wake-up circuit for an in-vehicle ECU and an in-vehicle ECU system. Combining with the actual application scenarios of new energy electric vehicles, the KL15 ignition wake-up signal and the CAN message signal are used as wake-up sources to sleep and wake up the MCU. Both the KL15 and the CAN message signal are inherent signals on new energy electric vehicles. When the sleep conditions are met, the MCU can directly power off and truly enter the low-power state.

[0008] Based on the first aspect of the present utility model, the following technical solutions are given:

[0009] A low-power sleep and wake-up circuit for an in-vehicle ECU, characterized in that it includes a CAN transceiver, a first DC voltage stabilizing circuit, a second DC voltage stabilizing circuit, and a microprocessor;

[0010] The first DC voltage stabilizing circuit is powered by a starting battery and outputs a first power supply;

[0011] The second DC voltage stabilizing circuit is powered by the first power supply and outputs a second power supply;

[0012] The CAN transceiver is a CAN transceiver with a specific frame wake-up function, having a first power supply pin, a second power supply pin, a wake-up pin, an INH pin, an SPI interface, a CAN bus interface, and a CAN data interface;

[0013] The first power supply pin is connected to the positive pole of the starting battery;

[0014] The second power supply pin is connected to the positive pole of the second power supply;

[0015] The SPI interface is connected to the SPI interface of the microprocessor;

[0016] The CAN data interface is connected to the CAN controller of the microprocessor;

[0017] The CAN bus interface is connected to the in-vehicle CAN bus;

[0018] The INH pin is connected to the enable terminal of the first DC voltage stabilizing circuit;

[0019] The ignition wake-up signal is connected to the wake-up pin of the CAN transceiver after passing through a voltage dividing circuit and is also connected to an IO port of the microprocessor;

[0020] The microprocessor is powered by the second power supply.

[0021] Further, the IO port is configured as a floating input or a pull-down input or an AD input.

[0022] Further, the model of the CAN transceiver is TPT1145.

[0023] Further, the first DC voltage stabilizing circuit includes a wide-voltage DC-DC converter, which allows the input voltage to include 12V and 24V; its output voltage is 12V.

[0024] Furthermore, the model of the wide-voltage DC-DC converter is JWQ5125.

[0025] Furthermore, the second DC voltage stabilizing circuit includes a buck DC-DC converter, and its output voltage is 5V or 3.3V.

[0026] Furthermore, the model of the buck DC-DC converter is LM2596S, and the output voltage is 5V.

[0027] Based on the first aspect of the present invention, the following technical solutions are provided:

[0028] A vehicle-mounted ECU system includes the vehicle-mounted ECU low-power sleep wake-up circuit described in any one of the above.

[0029] The present invention achieves the following technical effects:

[0030] The present invention provides a low-power sleep wake-up circuit with simple implementation, low cost and high reliability. When the MCU system enters the power-down state, in the low-power state, only the CAN transceiver of the entire vehicle-mounted ECU system is in the sleep state and a small part of the power supply circuit works. The entire vehicle-mounted ECU system has low power consumption, greatly saves energy, and avoids waste of the vehicle-mounted battery power. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 is the circuit principle block diagram of the present invention;

[0032] Figure 2 is the circuit diagram of the first DC voltage stabilizing circuit of an embodiment;

[0033] Figure 3 is the circuit diagram of the second DC voltage stabilizing circuit of an embodiment. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] To further illustrate the embodiments, the present invention provides drawings. These drawings are part of the disclosure of the present invention, which are mainly used to illustrate the embodiments and can be used to explain the operation principle of the embodiments in conjunction with the relevant descriptions in the specification. With reference to these contents, those of ordinary skill in the art should be able to understand other possible implementation manners and the advantages of the present invention.

[0035] The present invention will be further described below in conjunction with the drawings and specific embodiments.

[0036] AsFigure 1 As shown in the figure, the utility model provides a low-power sleep and wake-up circuit for an in-vehicle ECU (electronic control unit), which is composed of functional modules such as a CAN transceiver 10, a first DC voltage stabilizing circuit 20, a second DC voltage stabilizing circuit 30, and an MCU 40.

[0037] The connected ignition wake-up signal KL15 is connected to the wake-up pin WAKE of the CAN transceiver 10 after being divided by resistors R1 and R2. The wake-up signal edge trigger (rising edge or falling edge) mode can be set through configuration. At the same time, the ignition wake-up signal KL15 enters an IO port of the MCU after being divided by resistors R1 and R2. The MCU will detect the level of the ignition wake-up signal KL15 through this pin to check whether the ignition wake-up signal KL15 is lost. Among the pins of the CAN transceiver 10, the pin BAT is the first power supply pin of the CAN transceiver 10, which is connected to the vehicle-mounted starting battery, as shown as VPP in the figure, to keep the CAN transceiver 10 in the powered state. As long as the pin BAT is powered, the register data of the CAN transceiver 10 will not be lost. At the same time, the CAN receiver part of the CAN transceiver 10 is powered by BAT and can receive CAN bus message signals. The pin VCC is the second power supply pin of the CAN transceiver 10, connected to a 5V power supply, to supply power to the CAN transmitter and the CAN bus of the CAN transceiver 10. SPI is a serial peripheral interface. The CAN transceiver 10 is connected to the MCU through the SPI communication bus. The MCU can configure the CAN transceiver 10 through the SPI bus to realize the state switching of the CAN transceiver 10. Its states include standby, sleep, and normal. The pin TXD is the CAN message data transmission pin of the CAN transceiver 10, and the pin RXD is the CAN message data reception pin of the CAN transceiver 10. These two pins are connected to the data transmission and reception pins of the CAN controller of the MCU to realize the transmission and reception of CAN message data. The pins CAN_H and CAN_L are the CAN bus interfaces of the CAN transceiver 10, representing CAN high and CAN low respectively. The pin INH (high-set pin) is an external power supply switching suppression switch. The level of this pin is high in the standby and normal states and low in the sleep state. This pin is connected to the enable pin EN of the first DC voltage stabilizer circuit 20. When the enable pin EN is at a high level, the first DC voltage stabilizer circuit 20 can work normally, that is, the output pin SW of the first DC voltage stabilizer circuit 20 can output a voltage of 12V. The function of the first DC voltage stabilizer circuit 20 is to convert the voltage of the starting battery power supply VPP into a stable DC output of 12V. The first DC voltage stabilizer circuit 20 supplies power to the second DC voltage stabilizer circuit 30. The second DC voltage stabilizer circuit 30 includes one or more buck-type DC-DC circuits to convert DC 12V into voltages such as DC 5V and DC 3.3V for output to supply power to the MCU and the CAN transceiver 10.

[0038] In this embodiment, the IO port of the MCU 40 connected to the ignition wake-up signal KL15 can be configured with input modes such as floating input, pull-down input, or AD input, etc.

[0039] In this embodiment, the CAN transceiver 10 uses the TPT1145 of Silergy Corporation; this chip has a low-power sleep mode and an INH output, and supports local wake-up (through the wake-up pin WAKE) and remote wake-up (through a specific CAN data frame).

[0040] As Figure 2 shown, the first DC voltage stabilization circuit 20 (voltage regulator) samples the automotive-grade JWQ5125 single-chip DC-DC converter, which has a wide input voltage range: 4.6V - 60V, adjustable output voltage, and functions of short-circuit protection, thermal protection, and current loss protection. The purpose of using a wide-voltage DC-DC converter is as follows: the voltage of the vehicle-mounted battery is usually 12V or 24V. Using a wide-voltage DC-DC converter can be compatible with different power supply voltage platforms. At the same time, the vehicle-mounted ECU has relatively high requirements for voltage stability. Using a wide-voltage DC-DC converter can ensure the stability of the voltage at the backend. This voltage stabilization circuit also has a short-circuit protection function, which can prevent the vehicle-mounted ECU system from being burned out due to the reverse connection of the positive and negative poles of the input power supply.

[0041] The second DC voltage stabilization circuit 30 operates at 12V, with a relatively low voltage, and a small-package, low-cost DC-DC converter can be used. As Figure 3 shown, the power supply of the MCU is usually 5V. To obtain a stable 5V power supply for the MCU, the conversion chip of the second DC voltage stabilization circuit 30 uses LM2596S-5.0, which can convert the front-end 12V voltage into a stable 5V output to supply power to the MCU 40 and the CAN transceiver 10.

[0042] The working principle of this circuit is described as follows:

[0043] ECU Sleep: When the MCU meets the sleep conditions (such as detecting the loss of the ignition wake-up signal KL15 through the IO port and the application layer logic determines that the sleep condition has been met), the MCU communicates with the CAN transceiver 10 through SPI to make the CAN transceiver 10 enter the sleep state; when the CAN transceiver 10 enters the sleep state, its INH pin will be set low, making the enable pin EN of the first DC voltage regulator circuit 20 at a low level, the first DC voltage regulator circuit 20 does not work and has no voltage output, and then the second DC voltage regulator circuit 30 has no voltage, so the MCU has no power supply, the MCU powers off, only the CAN transceiver 10 works in the sleep state, and the entire circuit enters the low-power state, greatly reducing the power consumption of the entire vehicle-mounted ECU system. Directly setting the IO port for inputting the ignition wake-up signal KL15 helps to trigger the sleep judgment when the ignition wake-up signal KL15 is lost, quickly confirm the reason for the loss of the ignition wake-up signal KL15, such as the KL15 line is loose, the system shuts down normally, etc., so as to make a timely response, enter the sleep mode or give an alarm. The application layer logic to judge whether to enter the sleep condition is prior art and is not the key point of the present utility model, so it will not be elaborated here.

[0044] KL15 Wake-up: When the ignition wake-up signal KL15 changes from low level to high level, the wake-up pin WAKE of the CAN transceiver 10 changes from low level to high level. The CAN transceiver 10 recognizes the edge trigger signal and the CAN transceiver 10 enters the standby state from the sleep state. At this time, the INH pin of the CAN transceiver 10 will be set high, so that the enable pin EN of the first DC voltage regulator circuit 20 is at a high level, the first DC voltage regulator circuit 20 enters the working state, outputs a 12V level, and then supplies power to the MCU through the second DC voltage regulator circuit 30, and the MCU powers on and wakes up to work.

[0045] CAN Network Management Message Wake-up: When there is a CAN network management message on the CAN bus, the CAN transceiver 10 enters the standby state from the sleep state and then enters the normal state; when entering the standby state, the INH pin of the CAN transceiver 10 will be set high, so that the enable pin EN of the first DC voltage regulator circuit 20 is at a high level, the voltage regulator enters the working state, outputs a 12V level, and then supplies power to the MCU through the second DC voltage regulator circuit 30, and the MCU powers on and wakes up to work.

[0046] The present utility model provides a low-power sleep wake-up circuit with simple implementation, low cost and high reliability. When the MCU system enters the power-off state, in the low-power state, only the CAN transceiver of the entire vehicle-mounted ECU system is in the sleep state and a small part of the power supply circuit works. The entire vehicle-mounted ECU system has low power consumption, greatly saves energy, and avoids the waste of the vehicle-mounted battery power supply.

[0047] The present utility model also provides a vehicle-mounted ECU system, which has the vehicle-mounted ECU low-power sleep wake-up circuit as described above.

[0048] Although the present utility model is specifically shown and described in conjunction with the preferred embodiments, those skilled in the art should understand that various changes can be made to the present utility model in terms of form and details without departing from the spirit and scope of the present utility model defined by the appended claims, and all of them fall within the protection scope of the present utility model.

Claims

1. A low-power sleep wake-up circuit for an on-vehicle ECU, characterized in that: It includes a CAN transceiver, a first DC voltage stabilizing circuit, a second DC voltage stabilizing circuit and a microprocessor; The first DC voltage stabilizing circuit is powered by a starting battery and outputs a first power supply; The second DC voltage stabilizing circuit is powered by the first power supply and outputs a second power supply; The CAN transceiver is a CAN transceiver with a specific frame wake-up function, having a first power pin, a second power pin, a wake-up pin, an INH pin, an SPI interface, a CAN bus interface and a CAN data interface; The first power pin is connected to the positive electrode of the starting battery; The second power supply pin is connected to the positive electrode of the second power supply; The SPI interface is connected to the SPI interface of the microprocessor; The CAN data interface is connected to the CAN controller of the microprocessor; The CAN bus interface is connected to the vehicle-mounted CAN bus; The INH pin is connected to the enable terminal of the first DC voltage stabilization circuit; The ignition wake-up signal is connected to the wake-up pin of the CAN transceiver after passing through the voltage divider circuit, and is connected to an IO port of the microprocessor; The microprocessor is powered by a second power supply.

2. The low-power sleep and wake-up circuit for the vehicle-mounted ECU as claimed in claim 1, characterized in that: The IO port is configured as a floating input, a pull-down input, or an AD input.

3. The low-power sleep and wake-up circuit for the vehicle-mounted ECU as claimed in claim 1, characterized in that: The model of the CAN transceiver is TPT1145.

4. The low-power sleep and wake-up circuit for the vehicle-mounted ECU as claimed in claim 1, characterized in that: The first DC voltage stabilizing circuit includes a wide voltage DC-DC converter, which allows input voltages including 12V and 24V; Its output voltage is 12V.

5. The low-power sleep and wake-up circuit for the vehicle-mounted ECU as claimed in claim 4, characterized in that: The model of the wide voltage DC-DC converter is JWQ5125.

6. The low-power sleep and wake-up circuit for the vehicle-mounted ECU as claimed in claim 4, characterized in that: The second DC voltage stabilizing circuit includes a step-down DC-DC converter, and its output voltage is 5V or 3.3V.

7. The low-power sleep and wake-up circuit for the vehicle-mounted ECU as claimed in claim 6, characterized in that: The model of the step-down DC-DC converter is LM2596S, and the output voltage is 5V.

8. A vehicle-mounted ECU system, characterized in that: A vehicle-mounted ECU low-power sleep and wake-up circuit is provided as described in any one of claims 1 to 7.

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