Wake-up circuit and communication module

Abstract

The utility model discloses a kind of wake-up circuit and communication module, it is related to battery management technical field, wherein, wake-up circuit includes first switch unit, second switch unit, first switch unit includes first PMOS pipe, first PMOS pipe includes first grid, first source, first drain, first pull-up resistance;Second switch unit includes second PMOS pipe, and second PMOS pipe includes second grid, second source, second drain and second pull-up resistance.The utility model's circuit can make battery management system after entering dormancy for a period of time, realize again wake-up function, reduce power consumption, reduce cost.

Description

Technical Field

[0001] This utility model relates to the field of battery management technology, and in particular to a wake-up circuit and a communication module. Background Technology

[0002] A battery management system (BMS) is a protection device for batteries and a bridge between batteries and load terminals. It provides overcharge, over-discharge, and over-temperature protection functions for batteries based on online monitoring of the actual battery usage status, ensuring the safe use of batteries. BMS is widely used in many fields such as electric vehicles, communication base stations, and robots.

[0003] In related technologies, when using a charging gun to charge an electric vehicle, the charging gun is inserted into the vehicle's charging port to wake up the battery management system (BMS). According to the BMS strategy, if the charging gun does not charge within a certain period, the BMS enters a dormant mode. To wake up the BMS for charging again, an auxiliary power supply is required. This necessitates setting up two circuits from the vehicle's charging port to the BMS. These circuits involve wiring harnesses and connectors, resulting in a complex circuit structure, increased battery consumption, and increased costs. Utility Model Content

[0004] This invention aims to at least partially solve one of the technical problems in related technologies. Therefore, the first objective of this invention is to propose a wake-up circuit that, by improving the existing charging CAN circuit, enables the re-wake-up of the battery management system that has entered sleep mode, reducing the power consumption of the battery management system when it is in sleep mode and improving charging efficiency; it also eliminates the conventional auxiliary power supply method for wake-up, thereby reducing material costs.

[0005] The second objective of this invention is to provide a communication module.

[0006] To achieve the above objectives, the first aspect of this utility model proposes a wake-up circuit, comprising: a first switching unit, including a first PMOS transistor, the first PMOS transistor including a first gate, a first source, a first drain, and a first pull-up resistor, the first gate being connected to a plug-in port for connecting a ground resistor, the first pull-up resistor being disposed between the first source and the first gate for pulling up the voltage level of the first gate; the first pull-up resistor may be selectively connected in parallel with a first voltage divider branch, the first voltage divider branch being provided with a first voltage divider resistor, the input terminal of the first voltage divider branch being connected to a second I / O port, and the ratio of the resistance values ​​of the first pull-up resistor and the first voltage divider resistor being greater than a first preset threshold; and a second switching unit, including a second PMOS transistor, the second PMOS transistor including a second gate, a second source, a second drain, and a second pull-up resistor, the second gate being connected to an RX receiving port, the second pull-up resistor being disposed between the second source and the second gate for pulling up the voltage of the second gate, and the second source being connected to the first drain.

[0007] In addition, the wake-up circuit described above according to this utility model may also have the following additional technical features:

[0008] Furthermore, the wake-up circuit described above also includes an MCU control unit, which includes a first I / O port, a CAN_RX receive port, and a second I / O port.

[0009] Furthermore, the wake-up circuit described above also includes a CAN communication unit, which includes a VIO power supply port, a VCC power supply port, an RX receiving port, and a mode control port. The VIO power supply port is connected to the first drain, the mode control port is connected to the first I / O port, and the RX receiving port is connected to the CAN_RX receiving port.

[0010] Furthermore, the aforementioned wake-up circuit also includes a power management unit, which includes a wake-up input terminal, a first power supply output terminal, and a second power supply output terminal. The wake-up input terminal is connected to the second drain and is used to receive a high-level wake-up pulse. The first power supply output terminal is connected to the VIO power supply port and the VCC power supply port. The second power supply output terminal is connected to the first source, the mode control port, and the first I / O port. The first power supply output terminal is used to provide a high-level voltage only when the power management unit is woken up, and the second power supply output terminal is used to continuously provide a high-level voltage.

[0011] Furthermore, a second voltage divider resistor is provided between the first gate and the plug-in port. The second voltage divider resistor is connected in series with the first pull-up resistor and the first voltage divider resistor. The resistance value of the second voltage divider resistor is equal to that of the first pull-up resistor.

[0012] Furthermore, a third voltage divider resistor is provided between the mode control port and the first I / O port. A second voltage divider branch is connected in parallel with the third voltage divider resistor. A fourth voltage divider resistor is provided in the second voltage divider branch. The ratio of the resistance values ​​of the fourth voltage divider resistor and the third voltage divider resistor is greater than a second preset threshold.

[0013] Furthermore, a fifth voltage divider resistor is provided between the second gate and the RX receiving port, and the fifth voltage divider resistor is connected in series with the second pull-up resistor.

[0014] Furthermore, when the plug-in port is not connected to a ground resistor: the MCU control unit is used to control the first I / O port and the second I / O port to be floating; the MCU control unit is also used to control the first voltage divider branch not to be connected to the first switching unit; the first pull-up resistor is used to pull up the voltage of the first gate to be the same as the voltage of the first source, so as to turn off the first switching unit; the first switching unit is used to control the second switching unit to be turned off; the power management unit is used to control the first power supply output terminal not to provide a high-level voltage and to control the second power supply output terminal to continuously provide a high-level voltage.

[0015] Furthermore, when a ground resistor is connected to the plug-in port: the MCU control unit controls the first I / O port to output a low level and controls the second I / O port to output a high level; the MCU control unit also controls the first voltage divider branch to connect to the first switching unit, so that the first voltage divider resistor and the first pull-up resistor are connected in parallel; the first pull-up resistor is used to control the voltage difference between the first gate and the first source to be less than the conduction voltage of the first gate, so that the first switching unit is turned off; the first switching unit is used to control the second switching unit to be turned off; the power management unit is used to control the first power supply output terminal to provide a high-level voltage and control the second power supply output terminal to continuously provide a high-level voltage; the first power supply output terminal is used to power the VIO power supply port and the VCC power supply port, so that the CAN communication unit enters Normal mode; the CAN communication unit is used to receive and send messages.

[0016] Furthermore, when the plug-in port is connected to a ground resistor, if the plug-in port does not start charging within a preset time interval: the power management unit controls the first power supply output terminal not to provide a high-level voltage and controls the second power supply output terminal to continuously provide a high-level voltage; the MCU control unit controls the first I / O port, the second I / O port to be floating and the VCC power supply port to be floating; the MCU control unit is also used to control the first voltage divider branch not to be connected to the first switching unit; the first voltage divider resistor is used to control the first pull-up resistor, the second voltage divider resistor, and the ground resistor to be connected in series, and the voltage difference between the first gate and the first source is greater than the conduction voltage of the first gate, so that the first switching unit is turned on; the first switching unit is used to provide a high-level voltage to the VIO power supply port based on the second power supply output terminal; the second power supply output terminal is used to provide a high-level voltage to the mode control port, so that the CAN communication unit enters Standby mode; wherein, Standby mode indicates that the CAN communication unit cannot receive and send messages.

[0017] Furthermore, the CAN communication unit is used to enter Normal mode according to the wake-up command; the CAN communication unit is also used to control the RX receiving port to change from high level to low level according to the charger handshake message; the RX receiving port is used to control the second switching unit to be turned on; the second switching unit is used to control the power management unit to be woken up; the power management unit is used to control the first power supply output terminal to provide a high level voltage and control the second power supply output terminal to continuously provide a high level voltage.

[0018] Furthermore, the level transition process of the CAN communication unit from Standby mode to Normal mode is from recessive level to dominant level, and then from dominant level to recessive level; the level transition process represented by the charger handshake message is from recessive level to dominant level, and then from dominant level to recessive level.

[0019] The wake-up circuit according to this utility model includes: a first switching unit, including a first PMOS transistor, the first PMOS transistor including a first gate, a first source, a first drain, and a first pull-up resistor, the first gate being connected to a plug-in port, the plug-in port being used to connect a ground resistor, the first pull-up resistor being disposed between the first source and the first gate, and used to pull up the voltage level of the first gate; the first pull-up resistor may be selectively connected in parallel with a first voltage divider branch, the first voltage divider branch being provided with a first voltage divider resistor, the input terminal of the first voltage divider branch being connected to a second I / O port, and the ratio of the resistance values ​​of the first pull-up resistor and the first voltage divider resistor being greater than a first preset threshold; a second switching unit, including a second PMOS transistor, the second PMOS transistor including a second gate, a second source, a second drain, and a second pull-up resistor, the second gate being connected to an RX receiving port, the second pull-up resistor being disposed between the second source and the second gate, and used to pull up the voltage of the second gate, the second source being connected to the first drain. Therefore, this circuit improves the existing charging CAN circuit to enable the re-wake-up of the battery management system that has entered sleep mode, thereby reducing the power consumption of the battery management system when it is in sleep mode and improving charging efficiency; it also eliminates the conventional auxiliary power supply mode for wake-up, thereby reducing material costs.

[0020] To achieve the above objectives, a second aspect of this utility model provides a communication module, which includes the aforementioned wake-up circuit.

[0021] According to the communication module of this utility model, by improving the existing charging CAN circuit through the above-mentioned wake-up circuit, the function of waking up the battery management system that has entered sleep mode is realized, which reduces the power consumption of the battery management system when it is in sleep mode and improves the charging efficiency; the conventional auxiliary power supply for wake-up mode is eliminated, thereby reducing material costs.

[0022] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of a wake-up circuit according to some embodiments of the present invention;

[0024] Figure 2 This is a schematic diagram illustrating the logic levels and dominance / recession of CAN according to some embodiments of the present invention;

[0025] Figure 3 This is a schematic diagram illustrating the duration of the charger handshake message transmission according to some embodiments of the present invention.

[0026] Figure 4 This is a block diagram of a communication module according to some embodiments of the present invention.

[0027] Explanation of reference numerals in the attached figures:

[0028] IC2 - MCU control unit, I / O1 - First I / O port, CAN_RX - CAN_RX receive port, I / O2 - Second I / O port, 8 - First voltage divider branch, R1 - First voltage divider resistor, Q1 - First switching unit, 20 - First PMOS transistor, 201 - First gate, 202 - First source, 203 - First drain, R2 - First pull-up resistor, 6 - Plug-in port, R10 - Resistor to ground, IC1 - CAN communication unit, VIO - VIO power supply port, VCC - VCC power supply port, RX - RX receive port, STB - Mode control port, Q2 - Second switching unit, 40 - Second PMOS transistor MOSFET, 401 - second gate, 402 - second source, 403 - second drain, R6 - second pull-up resistor, IC3 - power management unit, WAK - wake-up input, PMIC_5V - first power supply output, 5V_Standby - second power supply output, R3 - second voltage divider resistor, R9 - third voltage divider resistor, 12 - second voltage divider branch, R4 - fourth voltage divider resistor, R5 - fifth voltage divider resistor, R8 - sixth voltage divider resistor, R7 - seventh voltage divider resistor, D1 - first diode, D2 - second diode, D3 - third diode, D4 ​​- fourth diode, 100 - wake-up circuit and 400 - communication module. Detailed Implementation

[0029] The embodiments of this utility model are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.

[0030] As mentioned in the background section, the battery management system (BMS) is a protection device for the battery and a bridge between the battery and the load terminal. It provides protection functions such as overcharge, over-discharge, and over-temperature based on the actual usage status of the battery monitored online, so as to ensure the safe use of the battery. Battery management systems are widely used in many fields such as electric vehicles, communication base stations, and robots.

[0031] In the process of realizing this utility model, the applicant discovered that in related technologies, the charging gun and the electric vehicle are provided with DC+, DC-, PE, S+, S-, CC2, A+, and A- interfaces, of which DC+ and DC- are high-voltage charging power interfaces, PE is the vehicle ground, S+ and S- are CAN signal interfaces, CC2 is the charging connection confirmation interface, and A+ and A- are low-voltage auxiliary power interfaces.

[0032] When using a charging gun to charge an electric vehicle, the charging gun is inserted into the charging port of the electric vehicle. A 1K resistor is pulled down at CC2 on the charging gun and connected to the CC2 interface of the battery management system (BMS) on the electric vehicle to wake up the BMS. According to the BMS strategy, if the charging gun does not charge for a certain period of time, such as by using A+ and A- auxiliary power supply and CAN communication to initiate handshake messages, the BMS will enter a sleep mode. To wake up the BMS for charging again, auxiliary power supply A+ and A- is required. This necessitates setting up two circuits from the vehicle's charging port to the BMS. These two circuits involve wiring harnesses and connectors, resulting in a complex circuit structure, increased battery consumption, and increased costs.

[0033] The wake-up circuit and communication module proposed in the embodiments of this utility model are described below with reference to the accompanying drawings.

[0034] refer to Figure 1 This is a schematic diagram of a wake-up circuit according to some embodiments of the present invention.

[0035] The wake-up circuit 100 of this application may include an MCU control unit IC2, a first switch unit Q1, a CAN communication unit IC1, a second switch unit Q2, and a power management unit IC3.

[0036] The MCU control unit IC2 includes a first I / O port I / O1, a CAN_RX receive port (CAN_RX), and a second I / O port I / O2. The MCU control unit IC2 is the core of the battery management system.

[0037] The first switching unit Q1 includes a first PMOS transistor 20, which includes a first gate 201, a first source 202, a first drain 203, and a first pull-up resistor R2. The first gate 201 is connected to a connector 6, which is used to connect a ground resistor R10. The first pull-up resistor R2 is located between the first source 202 and the first gate 201 to pull up the voltage level of the first gate 201. The first pull-up resistor R2 may be optionally connected in parallel with a first voltage divider branch 8, which includes a first voltage divider resistor R1. The input of the first voltage divider branch 8 is connected to the second I / O port I / O2 of the MCU control unit IC2. The ratio of the resistance value of the first pull-up resistor R2 (e.g., 47KΩ) to the resistance value of the first voltage divider resistor R1 (e.g., 1KΩ) is greater than a first preset threshold (e.g., ...). When the MCU control unit IC2 outputs a high level through the second I / O port I / O2, the first voltage divider branch 8 is connected to the first switch unit Q1, and the first voltage divider resistor R1 is connected in parallel with the first pull-up resistor R2; when the second I / O port I / O2 is floating, the first voltage divider branch 8 is not connected to the first switch unit Q1.

[0038] A second voltage divider resistor R3 is provided between the first gate 201 of the first switching unit Q1 and the plug-in port 6. When the charging gun is plugged in, the second voltage divider resistor R3 is connected in series with the first pull-up resistor R2 and the first voltage divider resistor R1. The resistance value of the second voltage divider resistor R3 (e.g., 47KΩ) is equal to the resistance value of the first pull-up resistor R2 (e.g., 47KΩ).

[0039] The CAN communication unit IC1 includes a VIO power supply port, a VCC power supply port, an RX receiving port, and a mode control port STB. The VIO power supply port is connected to the first drain 203, the STB is connected to the first I / O port I / O1, the RX receiving port is connected to the CAN_RX receiving port, and a sixth voltage divider resistor R8 is provided between the RX receiving port and the CAN_RX receiving port. The CAN communication unit IC1 is used to convert the TX and RX signals for communication with the MCU into differential signals CANH and CANL.

[0040] A third voltage divider resistor R9 is provided between the mode control port STB of the CAN communication unit IC1 and the first I / O port I / O1. The third voltage divider resistor R9 is connected in parallel with a second voltage divider branch 12. The second voltage divider branch 12 is provided with a third voltage divider resistor R4. The ratio of the resistance value of the third voltage divider resistor R4 (e.g., 10KΩ) to the resistance value of the third voltage divider resistor R9 (e.g., 1KΩ) is greater than or equal to a second preset threshold (e.g., ...). ).

[0041] The second switching unit Q2 includes a second PMOS transistor 40, which includes a second gate 401, a second source 402, a second drain 403, and a second pull-up resistor R6. The second gate 401 is connected to the RX receiving port RX. The second pull-up resistor R6 is disposed between the second source 402 and the second gate 401 to pull up the voltage of the second gate 401. The second source 402 is connected to the first drain 203.

[0042] A fifth voltage divider resistor R5 is provided between the second gate 401 of the second switching unit Q2 and the RX receiving port RX of the CAN communication unit IC1. The fifth voltage divider resistor R5 is connected in series with the second pull-up resistor R6, and a seventh voltage divider resistor R7 is provided at the second drain 403.

[0043] The power management unit IC3 includes a wake-up input terminal WAK, a first power supply output terminal PMIC_5V, and a second power supply output terminal 5V_Standby. The wake-up input terminal WAK is connected to the second drain 403 and is used to receive a high-level wake-up pulse. The first power supply output terminal PMIC_5V is connected to the VIO power supply port VIO and the VCC power supply port VCC. The second power supply output terminal 5V_Standby is connected to the first source 202, the mode control port STB, the second voltage divider branch 12, and the first I / O port I / O1. The first power supply output terminal PMIC_5V is used to provide a high-level voltage (e.g., 5V) only when the power management unit IC3 is woken up, and the second power supply output terminal 5V_Standby is used to continuously provide a high-level voltage. In digital logic circuits, a low level represents 0, and a high level represents 1. Generally, the low level is defined as 0 to 0.25V, and the high level as 3.5 to 5V.

[0044] The first diode D1 is positioned between the ground resistor R10 and the second voltage divider resistor R3. The second diode D2 is positioned between the first drain 203 and the VIO power supply port VIO. The third diode D3 is positioned between the VIO power supply port VIO and the VCC power supply port VCC. The fourth diode D4 is positioned between the second drain 403 and the wake-up input terminal WAK. Diodes can be used as electronic switches to control the flow of current. Diodes are commonly used in logic gate circuits. Diodes are also used to protect circuits from reverse voltage or voltage surges.

[0045] When the plug-in port 6 is not connected to the ground resistor R10: the MCU control unit IC2 is used to control the first I / O port I / O1 and the second I / O port I / O2 to be floating; the MCU control unit IC2 is also used to control the first voltage divider branch 8 not to be connected to the first switch unit Q1; the first pull-up resistor R2 is used to pull up the voltage of the first gate 201 to be the same as the voltage of the first source 202, so that the first switch unit Q1 is turned off; the first switch unit Q1 is used to control the second switch unit Q2 to be turned off; the power management unit IC3 is used to control the first power supply output terminal PMIC_5V not to provide a high level voltage and to control the second power supply output terminal 5V_Standby to continuously provide a high level voltage.

[0046] When the charging gun is not connected to the plug port 6 and the plug port 6 is not connected to the ground resistor R10, the battery management system is not woken up, the MCU control unit IC2 does not work, the first I / O port I / O1 and the second I / O port I / O2 of the MCU control unit IC2 are floating, the first voltage divider branch 8 is not connected to the first switch unit Q1, that is, the first voltage divider resistor R1 is not connected to the first pull-up resistor R2, and the second voltage divider resistor R3 is not connected to the first pull-up resistor R2.

[0047] The voltage of the first gate 201 of the first switching unit Q1 is pulled up by the first pull-up resistor R2 to be the same as the voltage of the first source 202. That is, when the voltage of the first source 202 is 5V, the voltage of the first gate 201 is 5V. The difference between the voltage of the first gate 201 and the voltage of the first source 202 is calculated. The difference between the voltage of the first gate 201 and the voltage of the first source 202 is compared with the conduction voltage of the first gate 201. When the difference between the voltage of the first gate 201 and the voltage of the first source 202 is less than the conduction voltage of the first gate 201, the first switching unit Q1 is turned off; when the difference between the voltage of the first gate 201 and the voltage of the first source 202 is greater than the conduction voltage of the first gate 201, the first switching unit Q1 is turned on. After comparing the difference between the voltage of the first gate 201 and the voltage of the first source 202 with the turn-on voltage of the first gate 201, it can be found that the difference between the voltage of the first gate 201 and the voltage of the first source 202 is less than the turn-on voltage of the first gate 201, that is, the first switching unit Q1 is turned off. Since the second source 402 of the second switching unit Q2 is not powered when the first switching unit Q1 is turned off, the second switching unit Q2 is also turned off. At the same time, the power management unit IC3 is not woken up, the first power supply output terminal PMIC_5V of the power management unit IC3 does not provide a high-level voltage, and the second power supply output terminal 5V_Standby of the power management unit IC3 continuously provides a high-level voltage. When the charging gun is first connected to the plug port 6, there is a short delay (about 200ms) in the wake-up of the battery management system because the electrical signal has a certain transmission time requirement in the circuit. During this time interval, the input terminal of the first voltage divider circuit 8 has not yet received the high-level signal sent by the second I / O port I / O2, and the first voltage divider circuit 8 is not connected to the first switching unit Q1, that is, the first voltage divider resistor R1 is not connected in parallel with the first pull-up resistor R2. However, when the plug-in port 6 is connected to a ground resistor R10 with a resistance of 1KΩ, the voltage of the first gate 201 of the first switching unit Q1 is less than the voltage of the first source 202. That is, when the voltage of the first source 202 is 5V, the voltage of the first gate 201 is less than 5V. The absolute value of the difference between the voltage of the first gate 201 and the voltage of the first source 202 is calculated. The absolute value of the difference between the voltage of the first gate 201 and the voltage of the first source 202 is compared with the conduction voltage of the first gate 201. It is found that the absolute value of the difference between the voltage of the first gate 201 and the voltage of the first source 202 is greater than the conduction voltage of the first gate 201. That is, the first switching unit Q1 is turned on, and the second source 402 of the second switching unit Q2 is powered.However, since the voltage of the second gate 401 of the second switching unit Q2 is pulled up by the second pull-up resistor R6 to be the same as the voltage of the second source 402, that is, when the voltage of the second source 402 is 5V, the voltage of the second gate 401 is 5V. Calculating the difference between the voltage of the second gate 401 and the voltage of the second source 402, and comparing the difference between the voltage of the second gate 401 and the voltage of the second source 402 with the conduction voltage of the second gate 401, it can be found that the difference between the voltage of the second gate 401 and the voltage of the second source 402 is less than the conduction voltage of the second gate 401, that is, the second switching unit Q2 is turned off.

[0048] When the plug-in port 6 is connected to the ground resistor R10: the MCU control unit IC2 is used to control the first I / O port I / O1 to output a low level and control the second I / O port I / O2 to output a high level; the MCU control unit IC2 is also used to control the first voltage divider branch 8 to connect to the first switch unit Q1, so that the first voltage divider resistor R1 and the first pull-up resistor R2 are connected in parallel; the first pull-up resistor R2 is used to control the voltage difference between the first gate 201 and the first source 202 to be less than the conduction voltage of the first gate 201, so that the first switch unit Q1 is turned off; the first switch unit Q1 is used to control the second switch unit Q2 to be turned off; the power management unit IC3 is used to control the first power supply output terminal PMIC_5V to provide a high level voltage and control the second power supply output terminal 5V_Standby to continuously provide a high level voltage; the first power supply output terminal PMIC_5V is used to supply power to the VIO power supply port VIO and the VCC power supply port VCC, so that the CAN communication unit IC1 enters the Normal mode; the CAN communication unit IC1 is used to receive and send messages.

[0049] When the charging gun is connected to the plug port 6 and the plug port 6 is connected to the ground resistor R10, the ground resistor is connected to the second voltage divider resistor R3, and the resistance of the ground resistor is 1KΩ. The battery management system is awakened, the MCU control unit IC2 works, and the first I / O port I / O1 of the MCU control unit IC2 is controlled to output a low level, and the second I / O port I / O2 of the MCU control unit IC2 is controlled to output a high level. The first voltage divider branch 8 is connected to the first switch unit Q1. The first voltage divider resistor R1 is connected in parallel with the first pull-up resistor R2 of the first switch unit Q1, and the second voltage divider resistor R3 is connected in series with the first voltage divider resistor R1 and the first pull-up resistor R2.

[0050] Since the resistance of the first voltage divider resistor R1 is much smaller than that of the first pull-up resistor R2 and the second voltage divider resistor R3, the voltage allocated to the first gate 201 of the first switching unit Q1 is greater. The voltage of the first gate 201 is calculated as the difference between the voltage of the first gate 201 and the voltage of the first source 202. This difference is compared with the on-state voltage of the first gate 201. It is found that the difference between the voltage of the first gate 201 and the voltage of the first source 202 is less than the on-state voltage of the first gate 201, meaning the first switching unit Q1 is off. Since the second source 402 of the second switching unit Q2 is not powered when the first switching unit Q1 is off, the second switching unit Q2 is also off. Simultaneously, the power management unit IC3 is awakened, and the first power supply output terminal PMIC_5V of the power management unit IC3 provides a high-level voltage. The second power supply output terminal 5V_Standby of the power management unit IC3 continuously provides a high-level voltage. The VIO power supply port VIO and the VCC power supply port VCC of the CAN communication unit IC1 are powered by the high-level voltage provided by the first power supply output terminal PMIC_5V of the power management unit IC3. The CAN communication unit IC1 enters the Normal mode, where the Normal mode indicates that the CAN communication unit IC1 can receive and send messages.

[0051] When plug-in port 6 is connected to ground resistor R10, if plug-in port 6 does not start charging within a preset time interval: Power management unit IC3 is used to control the first power supply output terminal PMIC_5V not to provide a high-level voltage and to control the second power supply output terminal 5V_Standby to continuously provide a high-level voltage; MCU control unit IC2 is used to control the first I / O port I / O1, the second I / O port I / O2 to be floating and the VCC power supply port VCC to be floating; MCU control unit IC2 is also used to control the first voltage divider branch 8 not to be connected to the first switch unit Q1; the first voltage divider resistor R1 is used to control the first pull-up resistor R2 and the first voltage divider resistor R1 to be connected to the first voltage divider branch 8. The voltage divider resistor R3 and the ground resistor R10 are connected in series, and the voltage difference between the first gate 201 and the first source 202 is greater than the conduction voltage of the first gate 201, so that the first switching unit Q1 is turned on; the first switching unit Q1 is used to provide a high-level voltage to the VIO power supply port VIO based on the second power supply output terminal 5V_Standby; the second power supply output terminal 5V_Standby is used to provide a high-level voltage to the mode control port STB, so that the CAN communication unit IC1 enters the Standby mode; wherein, the Standby mode indicates that the CAN communication unit IC1 cannot receive and send messages.

[0052] After the charging gun is connected to the plug-in port 6 and the plug-in port 6 is connected to the ground resistor R10, if the plug-in port 6 does not start charging within a preset time interval, the battery management system enters sleep mode, and the power management unit IC3 enters sleep mode to reduce energy consumption. The first power supply output terminal PMIC_5V of the power management unit IC3 does not provide a high-level voltage, and the second power supply output terminal 5V_Standby of the power management unit IC3 continuously provides a high-level voltage. Since the MCU control unit IC2 is provided with a high-level voltage by the first power supply output terminal PMIC_5V of the power management unit IC3, the MCU control unit IC2 enters power-down mode. The first I / O port I / O1 and the second I / O port I / O2 of the MCU control unit IC2 are floating. The first voltage divider branch 8 is not connected to the first switch unit Q1, that is, the first voltage divider resistor R1 is not connected to the first pull-up resistor R2. The first pull-up resistor R2 is connected in series with the second voltage divider resistor R3 and the ground resistor R10.

[0053] The difference between the voltage of the first gate 201 and the voltage of the first source 202 of the first switching unit Q1 is calculated. This difference is compared with the turn-on voltage of the first gate 201. Since the difference is greater than the turn-on voltage, the first switching unit Q1 is turned on. Simultaneously, the power management unit IC3 is not activated. The first power supply output terminal PMIC_5V of the power management unit IC3 does not provide a high-level voltage, while the second power supply output terminal 5V_Standby of the power management unit IC3 continuously provides a high-level voltage. The VIO power supply port VIO of the CAN communication unit IC1 is supplied with a high-level voltage through the first switching unit Q1 via the second power supply output terminal 5V_Standby of the power management unit IC3. The VCC power supply port VCC of the CAN communication unit IC1 is left floating.

[0054] The mode control port STB of the CAN communication unit IC1 is supplied with a high-level voltage by the second power supply output terminal 5V_Standby of the power management unit IC3. When the CAN communication unit IC1 enters Standby mode, it waits to receive a wake-up command. Standby mode indicates that the CAN communication unit IC1 cannot receive or send messages. The Standby mode can detect whether a message has appeared on the CAN bus by detecting the RXD pin, and then it can be used to realize the message wake-up detection of the MCU.

[0055] The CAN communication unit IC1 is used to enter Normal mode according to the wake-up command; the CAN communication unit IC1 is also used to control the RX receiving port RX to change from high level to low level according to the charger handshake message; the RX receiving port RX is used to control the second switch unit Q2 to be turned on; the second switch unit Q2 is used to control the power management unit IC3 to be woken up; the power management unit IC3 is used to control the first power supply output terminal PMIC_5V to provide a high level voltage and control the second power supply output terminal 5V_Standby to continuously provide a high level voltage.

[0056] When the APP sends a wake-up command, and the CAN communication unit IC1 receives the command, it enters Normal mode. The charging pile sends a charger handshake message. When the CAN communication unit IC1 receives the message, its RX receiver port changes from high to low, and the second switch Q2 is turned on. The battery management system is then activated, and the power management unit IC3 is also activated. The first power supply output terminal PMIC_5V of the power management unit IC3 provides a high-level voltage, and the second power supply output terminal 5V_Standby continuously provides a high-level voltage.

[0057] When the charging station is swiped or the charging reservation is triggered by the APP, the CAN communication unit receives the charger handshake message (message code CHM). This message will be sent for about 6 seconds, with a period of 250ms. The specific content of the message is shown in Table 1. In this table, PGN(Dec) is the parameter group number (decimal) and PGN(Hex) is the parameter group number (hexadecimal).

[0058] Table 1

[0059]

[0060] refer to Figure 2 The diagram shows the logic levels and dominance / recessiveness of CAN according to some embodiments of the present invention. Converting 002600H to binary gives 0000 0000 0010 0110 0000, where "0" represents dominance and "1" represents recessiveness.

[0061] refer to Figure 3 This is a schematic diagram of the duration of the charger handshake message transmission according to some embodiments of the present invention. Since the communication rate is 250kbps, the duration of 1 bit is 4us.

[0062] The level transition process of CAN communication unit IC1 from Standby mode to Normal mode is from recessive level to dominant level, and then from dominant level back to recessive level. The level transition process represented by the charger handshake message is from recessive level to dominant level, and then from dominant level back to recessive level.

[0063] Common CAN chips such as NXP TJA1044 and TI TCAN1044, or CAN chips with INH wake-up interface functionality such as TJA1043 or TJA1145 can be used.

[0064] In some embodiments, when the current mode is Standby mode and it is necessary to switch the current mode to Normal mode, the mode control port STB of CAN communication unit IC1 is adjusted to a low level; when the current mode is Normal mode and it is necessary to switch the current mode to Standby mode, the mode control port STB of CAN communication unit IC1 is adjusted to a high level.

[0065] In summary, the wake-up circuit according to this utility model includes: a first switching unit, including a first PMOS transistor, the first PMOS transistor including a first gate, a first source, a first drain, and a first pull-up resistor, the first gate being connected to a plug-in port, the plug-in port being used to connect a ground resistor, the first pull-up resistor being disposed between the first source and the first gate, and used to pull up the voltage level of the first gate; the first pull-up resistor may be selectively connected in parallel with a first voltage divider branch, the first voltage divider branch being provided with a first voltage divider resistor, the input terminal of the first voltage divider branch being connected to a second I / O port, and the ratio of the resistance values ​​of the first pull-up resistor and the first voltage divider resistor being greater than a first preset threshold; a second switching unit, including a second PMOS transistor, the second PMOS transistor including a second gate, a second source, a second drain, and a second pull-up resistor, the second gate being connected to an RX receiving port, the second pull-up resistor being disposed between the second source and the second gate, and used to pull up the voltage of the second gate, the second source being connected to the first drain. Therefore, this circuit improves the existing charging CAN circuit to enable the re-wake-up of the battery management system that has entered sleep mode, thereby reducing the power consumption of the battery management system when it is in sleep mode and improving charging efficiency; it also eliminates the conventional auxiliary power supply mode for wake-up, thereby reducing material costs.

[0066] refer to Figure 4 This is a block diagram of the communication module according to an embodiment of the present utility model.

[0067] like Figure 4 As shown, the communication module 400 includes the wake-up circuit 100 described above.

[0068] According to the communication module of this utility model embodiment, by improving the existing charging CAN circuit through the above-mentioned wake-up circuit, the function of waking up the battery management system that has entered sleep mode is realized, thereby reducing the power consumption of the battery management system when it is in sleep mode and improving the charging efficiency; the conventional auxiliary power supply for wake-up mode is eliminated, thereby reducing material costs.

[0069] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0070] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0071] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0072] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0073] In this utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0074] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A wake-up circuit, characterized in that, include: The first switching unit (Q1) includes a first PMOS transistor (20), which includes a first gate (201), a first source (202), a first drain (203), and a first pull-up resistor (R2). The first gate (201) is connected to a plug-in port (6), which is used to connect a ground resistor (R10). The first pull-up resistor (R2) is disposed between the first source (202) and the first gate (201) and is used to pull up the level of the first gate (201). The first pull-up resistor (R2) may be selectively connected in parallel with a first voltage divider branch (8), which is provided with a first voltage divider resistor (R1). The input terminal of the first voltage divider branch (8) is connected to a second I / O port (I / O2). The ratio of the resistance values ​​of the first pull-up resistor (R2) and the first voltage divider resistor (R1) is greater than a first preset threshold. The second switching unit (Q2) includes a second PMOS transistor (40), which includes a second gate (401), a second source (402), a second drain (403), and a second pull-up resistor (R6). The second gate (401) is connected to the RX receiver port (RX). The second pull-up resistor (R6) is disposed between the second source (402) and the second gate (401) to pull up the voltage of the second gate (401). The second source (402) is connected to the first drain (203).

2. The wake-up circuit according to claim 1, characterized in that, It also includes an MCU control unit (IC2), which includes a first I / O port (I / O1), a CAN_RX receive port (CAN_RX), and a second I / O port (I / O2).

3. The wake-up circuit according to claim 2, characterized in that, It also includes a CAN communication unit (IC1), which includes a VIO power supply port (VIO), a VCC power supply port (VCC), an RX receiving port (RX), and a mode control port (STB). The VIO power supply port (VIO) is connected to the first drain (203), the mode control port (STB) is connected to the first I / O port (I / O1), and the RX receiving port (RX) is connected to the CAN_RX receiving port (CAN_RX).

4. The wake-up circuit according to claim 3, characterized in that, It also includes a power management unit (IC3), which includes a wake-up input (WAK), a first power output (PMIC_5V), and a second power output (5V_Standby). The wake-up input (WAK) is connected to the second drain (403) and is used to receive a high-level wake-up pulse. The first power output (PMIC_5V) is connected to the VIO power supply port (VIO) and the VCC power supply port (VCC). The second power output (5V_Standby) is connected to the first source (202), the mode control port (STB), and the first I / O port (I / O1). The first power output (PMIC_5V) is used to provide a high-level voltage only when the power management unit (IC3) is woken up, and the second power output (5V_Standby) is used to continuously provide a high-level voltage.

5. The wake-up circuit according to claim 4, characterized in that, A second voltage divider resistor (R3) is provided between the first gate (201) and the plug-in port (6). The second voltage divider resistor (R3) is connected in series with the first pull-up resistor (R2) and the first voltage divider resistor (R1). The resistance value of the second voltage divider resistor (R3) is equal to that of the first pull-up resistor (R2).

6. The wake-up circuit according to claim 5, characterized in that, A third voltage divider resistor (R9) is provided between the mode control port (STB) and the first I / O port (I / O1). The third voltage divider resistor (R9) is connected in parallel with a second voltage divider branch (12). The second voltage divider branch (12) is provided with a fourth voltage divider resistor (R4). The ratio of the resistance values ​​of the fourth voltage divider resistor (R4) to the third voltage divider resistor (R9) is greater than a second preset threshold.

7. The wake-up circuit according to claim 6, characterized in that, A fifth voltage divider resistor (R5) is provided between the second gate (401) and the RX receiving port (RX), and the fifth voltage divider resistor (R5) is connected in series with the second pull-up resistor (R6).

8. The wake-up circuit according to claim 7, characterized in that, When the plug-in port (6) is not connected to the ground resistor (R10): The MCU control unit (IC2) is used to control the first I / O port (I / O1) and the second I / O port (I / O2) to be left floating; The MCU control unit (IC2) is also used to control the first voltage divider branch (8) to not be connected to the first switch unit (Q1); The first pull-up resistor (R2) is used to pull up the voltage of the first gate (201) to the same voltage as the first source (202) so that the first switching unit (Q1) is turned off; The first switching unit (Q1) is used to control the second switching unit (Q2) to turn off; The power management unit (IC3) is used to control the first power supply output terminal (PMIC_5V) to not provide a high-level voltage and to control the second power supply output terminal (5V_Standby) to continuously provide a high-level voltage.

9. The wake-up circuit according to claim 7, characterized in that, When the plug-in port (6) is connected to the ground resistor (R10): The MCU control unit (IC2) is used to control the first I / O port (I / O1) to output a low level and control the second I / O port (I / O2) to output a high level; The MCU control unit (IC2) is also used to control the first voltage divider branch (8) to be connected to the first switching unit (Q1) so that the first voltage divider resistor (R1) and the first pull-up resistor (R2) are connected in parallel; The first pull-up resistor (R2) is used to control the voltage difference between the first gate (201) and the first source (202) to be less than the turn-on voltage of the first gate (201), so that the first switching unit (Q1) is turned off. The first switching unit (Q1) is used to control the second switching unit (Q2) to turn off; The power management unit (IC3) is used to control the first power supply output terminal (PMIC_5V) to provide a high-level voltage and to control the second power supply output terminal (5V_Standby) to continuously provide a high-level voltage; The first power output terminal (PMIC_5V) is used to supply power to the VIO power supply port (VIO) and the VCC power supply port (VCC) so that the CAN communication unit (IC1) enters Normal mode; The CAN communication unit (IC1) is used to receive and send messages.

10. The wake-up circuit according to claim 9, characterized in that, If the plug port (6) does not start charging within a preset time interval after the ground resistor (R10) is connected to the plug port (6): The power management unit (IC3) is used to control the first power supply output terminal (PMIC_5V) to not provide a high-level voltage and to control the second power supply output terminal (5V_Standby) to continuously provide a high-level voltage; The MCU control unit (IC2) is used to control the first I / O port (I / O1), the second I / O port (I / O2) to be floating and the VCC power supply port (VCC) to be floating. The MCU control unit (IC2) is also used to control the first voltage divider branch (8) to not be connected to the first switch unit (Q1); The first voltage divider resistor (R1) is used to control the first pull-up resistor (R2) to be connected in series with the second voltage divider resistor (R3) and the ground resistor (R10), and the voltage difference between the first gate (201) and the first source (202) is greater than the turn-on voltage of the first gate (201) so that the first switching unit (Q1) is turned on. The first switching unit (Q1) is used to provide a high-level voltage to the VIO power supply port (VIO) based on the second power supply output terminal (5V_Standby); The second power supply output terminal (5V_Standby) is used to provide a high-level voltage to the mode control port (STB) so that the CAN communication unit (IC1) enters the Standby mode; wherein, the Standby mode indicates that the CAN communication unit (IC1) cannot receive and send messages.

11. The wake-up circuit according to claim 10, characterized in that, The CAN communication unit (IC1) is used to enter Normal mode according to the wake-up command; The CAN communication unit (IC1) is also used to control the RX receiving port (RX) to change from high level to low level according to the charger handshake message; The RX receiving port (RX) is used to control the second switching unit (Q2) to be turned on; The second switching unit (Q2) is used to control the power management unit (IC3) to be woken up; The power management unit (IC3) is used to control the first power supply output terminal (PMIC_5V) to provide a high-level voltage and to control the second power supply output terminal (5V_Standby) to continuously provide a high-level voltage.

12. The wake-up circuit according to claim 11, characterized in that, The level transition process of the CAN communication unit (IC1) from the Standby mode to the Normal mode is as follows: from the recessive level to the dominant level, and then from the dominant level back to the recessive level. The level transition process represented by the charger handshake message is from a recessive level to a dominant level, and then from a dominant level back to a recessive level.

13. A communication module, characterized in that, The communication module (400) includes a wake-up circuit (100) as described in any one of claims 1 to 12.

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