CN112009306A

CN112009306A - Wake-up and dormancy circuit of AC charging CP signal

Info

Publication number: CN112009306A
Application number: CN202010812303.9A
Authority: CN
Inventors: 张明艳
Original assignee: Lishen Power Battery System Co Ltd
Current assignee: Lishen Qingdao New Energy Co Ltd
Priority date: 2020-08-13
Filing date: 2020-08-13
Publication date: 2020-12-01

Abstract

The invention discloses a circuit for waking up and sleeping a CP (charge control) signal during alternating current charging, which is characterized by comprising a 5V normal power module, a CP signal conversion module, a D trigger module, a D latch module, a BMS (battery management system) main control chip, a selection switch module and a power supply module, wherein: the 5V constant-current module is respectively connected with the CP signal conversion module, the D trigger module and the D latch module; the CP signal conversion module is sequentially connected with the D trigger module, the D latch module, the selection switch module and the power supply module; the BMS main control chip is respectively connected with the D trigger module, the D latch module, the selection switch module and the power module, and the invention realizes the functions of automatically awakening the BMS by the AC charging CP signal and automatically sleeping the BMS by the logic combination control of the high and low level changes of the input and output signals of the D trigger and the D latch, thereby having great production practice significance.

Description

Wake-up and dormancy circuit of AC charging CP signal

Technical Field

The invention relates to the technical field of battery management, in particular to a circuit for waking up and sleeping a CP (charge control) signal during alternating current charging.

Background

A Battery Management System (BMS), which is a Battery protection device and is also a bridge between a Battery and a load terminal, provides protection functions such as overcharge, overdischarge, and over-temperature for the Battery according to the actual usage state of the Battery monitored on line, and ensures that the Battery is safely used. The battery management system BMS is widely used in various fields such as electric vehicles, communication base stations, and robots.

Taking an electric automobile as an example, when an alternating current charging mode is adopted to charge a vehicle-mounted power battery system (hereinafter referred to as a battery system), if a charging gun on an automobile charging pile is not pulled out for a long time after charging is finished, the battery system can cause the power consumption to affect the endurance mileage of the automobile; it can also result in the on-board battery feeding affecting the normal use of the on-board electrical and electronic components (including the BMS).

The reasons for the above problems are: after charging, the charging gun is not pulled out, and the charging gun always keeps 12V voltage for a charging wake-up CP (CP, namely, charging wake-up) signal of the battery management system BMS, so that the battery management system BMS cannot enter a low-power-consumption dormant state, but continues to keep a high-power-consumption normal working state. At this time, if the battery management system BMS is powered by the on-vehicle DC/DC power source (supplied with power from the battery system), the DC/DC power source consumes the power of the battery system by continuously supplying power to the battery management system BMS; if the battery management system BMS is powered by the on-board battery cell, the battery management system BMS will always consume the on-board battery cell.

At present, there are two kinds of charging wake-up CP signals in the ac charging mode: 12V or PWM signal.

In view of the above problems, some prior art schemes wake up the BMS and control the BMS to sleep by using the PWM signal output from the ac charging interface CP terminal (i.e., the charging wake-up terminal), but the PWM signal detection and processing circuit and the PWM signal driving circuit of these prior art schemes are relatively complex in structure and relatively high in design cost.

Therefore, there is a need to develop a wake-up and sleep scheme for ac charging CP signal that does not use PWM signal as trigger signal and is low in cost.

Disclosure of Invention

The invention aims to provide a circuit for waking up and sleeping an alternating current charging CP signal, aiming at the technical defects in the prior art.

Therefore, the invention provides a circuit for waking up and sleeping AC charging CP signals, which comprises a 5V constant current module, a CP signal conversion module, a D trigger module, a D latch module, a BMS main control chip, a selection switch module and a power supply module, wherein:

the 5V constant-current module is respectively connected with the CP signal conversion module, the D trigger module and the D latch module and is used for providing continuous 5V direct current output for the CP signal conversion module, the D trigger module and the D latch module;

the CP signal conversion module is provided with two input ends which are respectively connected with the output end CP of the charging gun charging interface and the output end of the 5V constant current module, and is used for converting the CP signal output by the output end CP of the charging gun charging interface into a 5V signal and then inputting a clock signal input end CLK of the D trigger module;

the D trigger module is provided with a signal input end D1 and a preset input end PRE which are respectively connected with the output end of the 5V constant current module;

the D trigger module is provided with a reset input CLR which is connected with the output end of the BMS main control chip;

the D flip-flop module is provided with a clock signal input end CLK connected with the output end of the CP signal conversion module and used for receiving the 5V signal input by the CP signal conversion module;

a D flip-flop module having an output connected to the input D2 of the D latch module for providing an input signal to the D latch module;

the D latch module is provided with a latch enable input end LEN which is connected with the output end of the 5V constant current module;

the D latch module is provided with an output enable input end OEN connected with the output end of the BMS main control chip and used for receiving an output state control signal output by the BMS main control chip;

a D latch module having an input terminal D2 connected to the output terminal of the D flip-flop module for receiving the output signal of the D flip-flop module;

the D latch module is provided with an output end connected with the input end of the selection switch module and used for inputting a charging wake-up signal WKUP to the selection switch module;

the BMS main control chip comprises three signal output ends, wherein a first signal output end of the BMS main control chip is connected with a reset input end CLR of the D trigger module and is used for providing a reset control signal for the D trigger module and controlling the high-low level state of an input signal of the reset input end CLR of the D trigger module;

the BMS main control chip is provided with a second signal output end which is connected with an output enable input end OEN of the D latch module and is used for providing an output state control signal for the D latch module so as to control the high-low level state of an input signal of the output enable input end OEN of the D latch module;

the BMS main control chip is provided with a third signal output end which is connected with the input end of the selection switch module and used for providing a charging awakening self-locking signal PWR for the selection switch module;

in addition, a power input end DVDD of the BMS master control chip is connected to an output end of the power module, and is configured to receive a direct current power output by the power module;

the BMS main control chip is provided with a PWM input end which is connected with the output end CP of the charging gun charging interface and is used for detecting a PWM signal provided by the output end CP of the charging gun charging interface and judging whether charging is finished;

the selection switch module comprises two signal input ends and is used for realizing an OR logic function;

the first signal input end of the selection switch module is connected with the output end of the D latch module and is used for receiving a charging wake-up signal WKUP input by the D latch module;

the second signal input end of the selection switch module is connected with the output of the BMS main control chip and used for receiving a charging awakening self-locking signal PWR output by the BMS main control chip;

the output end of the selection switch module is connected with a power supply enabling input end EN of the power supply module and is used for providing a power supply enabling signal EN for the power supply module so as to control the on-off of the power supply output of the power supply module;

the power supply module is provided with a power supply output enabling input end EN which is connected with the output end of the selection switch module and is used for receiving a power supply enabling signal EN output by the selection switch module, and the high-low level state of the power supply enabling signal EN controls whether the power supply module outputs direct-current power supply or not;

the output of power module connects BMS main control chip's power input DVDD, and when power module exported DC power supply, power module does BMS main control chip supplies power to awaken battery management system BMS, and when power module did not export DC power supply, stopped doing BMS main control chip supplies power, thereby makes BMS dormancy.

The input end of the 5V constant-power module is connected with an external constant-

power

12V or 24V power supply.

The CP signal conversion module 200 includes a switch K1, a switch K2, a resistor R15, a resistor R16, and a resistor R17, wherein:

the controlled end of the switch K1 is connected with the output end CP of the charging interface of the charging gun;

one end of the switch K1 is connected with the 2 nd pin of the resistor R15;

the other end of the switch K1 is connected with a ground end GND;

the controlled end of the switch K2 is connected with the 1 st pin of the resistor R15;

one end of the switch K2 is connected with the output end of the 5V constant-current module;

the other end of the switch K2 is connected with the 1 st pin of the resistor R16;

the 1 st pin of the resistor R17 is connected with the 2 nd pin of the resistor R16 and the clock signal input end CLK of the D flip-flop module;

the 2 nd pin of the resistor R17 is connected to the ground GND.

The D trigger module comprises a D trigger and a zero clearing control circuit, and the D trigger is connected with the zero clearing control circuit;

the D trigger is edge-triggered and has preset and zero clearing functions, and the zero clearing control circuit is connected with a first signal output end of the BMS main control chip and used for receiving a zero clearing control signal output by the BMS main control chip so as to control whether the zero clearing function of the D trigger is effective or not.

The D trigger module comprises a D trigger, a resistor R1, a resistor R2, a resistor R3, a resistor R8 and a zero clearing control circuit, wherein:

the zero clearing control circuit comprises resistors R4, R5, R6, R7 and an enhanced N-channel field effect transistor Q1;

the power supply input end VCC of the D trigger is connected with the 2 nd pin of the resistor R1;

preset input terminal of D flip-flop

The end of the second pin is connected with the No. 2 pin of the resistor R2;

the input end D of the D trigger is connected with the 2 nd pin of the resistor R3;

reset input terminal of D trigger

The 1 st pin of the resistor R5 is connected;

the output end Q of the D trigger is connected with the 1 st pin of the resistor R8;

a clock signal input end CLK of the D trigger is connected with an output end of the CP signal conversion module;

the 1 st pin of the resistor R1, the 1 st pin of the resistor R2 and the 1 st pin of the resistor R3 are respectively connected with the output end of the 5V constant-current module;

the 2 nd pin of the resistor R8 is connected with the 1 st pin of the resistor R9;

the 2 nd pin of the resistor R9 is connected with the ground terminal GND;

the 2 nd pin of the resistor R5 is respectively connected with the 2 nd pin of the resistor R4 and the drain D of the NMOS transistor Q1;

the 1 st pin of the resistor R4 is connected with the output end of the 5V constant-current module;

the grid G of the NMOS tube Q1 is respectively connected with the 1 st pin of the resistor R6 and the 2 nd pin of the resistor R7;

the source S of the NMOS tube Q1 and the 1 st pin of the resistor R7 are respectively connected with a ground terminal GND;

and the 2 nd pin of the resistor R6 is connected with a third signal output end of the BMS main control chip.

The D latch module comprises a D latch and an output control circuit, and the D latch is connected with the output control circuit;

the D latch has a tristate gate output function;

and the output control circuit is connected with the second signal output end of the BMS main control chip and is used for receiving an output enable signal OEN output by the BMS main control chip.

The D latch module comprises a D latch, a resistor R10, a resistor R11, a resistor R14 and an output control circuit;

the output control circuit comprises a resistor R12 and a resistor R13;

the power supply input end VCC of the D latch is connected with the 2 nd pin of the resistor R11;

the latch input end LE of the D latch is connected with the 2 nd pin of the resistor R10;

the input end D of the D latch is respectively connected with the 2 nd pin of the resistor R8 and the 1 st pin of the resistor R9;

output enable input terminal of D latch

The 2 nd pin of the resistor R12 and the 1 st pin of the resistor R13 are respectively connected;

the output end Q of the D latch is connected with the 1 st pin of the resistor R14 and the input end of the selection switch module;

the 1 st pin of the resistor R10 and the 1 st pin of the resistor R11 are respectively connected with the output end of the 5V constant-current module;

the 1 st pin of the resistor R12 is connected with a ground end GND;

the 2 nd pin of the resistor R13 is respectively connected with the 2 nd pin of the resistor R6 and a third signal output end of the BMS main control chip;

the 2 nd pin of the resistor R14 is connected to the ground GND.

The circuit wakes up the control logic strategy of the battery management system BMS through the CP signal as follows:

step S0: before the charging gun is inserted, a CP signal output by an output end CP of a charging interface of the charging gun is 0V, the BMS is in a dormant state, no zero clearing control signal is input into the D trigger module by the BMS main control chip, so that the zero clearing function of the D trigger module is invalid, namely, the output end of the D trigger module is changed along the same direction of an input signal of the D trigger module after a rising edge effective signal appears in a clock signal CLK, and the output of the D trigger module is a low level signal when the clock signal CLK is invalid; the BMS main control chip does not output a state control signal to the D latch module, so that the high-resistance state output of the D latch module is invalid, namely the output of the D trigger module changes along the same direction of the input signal thereof, and the output charging wake-up signal WKUP is a low-level signal;

step S1: before a charging gun is inserted and charging is started, a CP signal output by an output end CP of a charging interface of the charging gun jumps from OV to 12V, a rising edge effective signal is input into a clock signal input end CLK of the D trigger module through the CP signal conversion module, the output of the D trigger module is triggered to change from low level to high level, a charging wake-up signal WKUP output by the D latch module is changed from low level to high level effective signal, a power supply enable signal EN output by the selection switch module is changed into high level, the power supply module is triggered to output a power supply to activate a BMS main control chip, and at the moment, the BMS is awakened preliminarily but charging is not allowed;

step S2: after the BMS is awakened initially, the BMS main control chip outputs a high-level charging awakening self-locking signal PWR for the selection switch module, a power supply enabling signal EN output by the selection switch module keeps the high level continuously, and the power supply module is controlled to output power supply to continuously supply power for the BMS main control chip; the BMS main control chip inputs a high-level zero clearing control signal to the D trigger module, so that the zero clearing function of the D trigger module is changed from invalid to valid, namely, the output signal of the D trigger module is locked from high level to low level until the zero clearing control signal is cancelled; the BMS main control chip inputs a high-level output state control signal to the D latch module, so that the high-resistance state output of the D latch is changed from invalid to valid, namely, a charging wake-up signal WKUP output by the D latch module is locked from high level to low level until the output state control signal is cancelled; to this end, the BMS is sufficiently awakened and allowed to charge.

After step S2, the method further includes the following steps:

step S3, when the charging of the charging gun is started, the CP signal output by the output end CP of the charging interface of the charging gun is changed from 12V to a PWM signal until the charging is finished, the rising edge of the PWM signal does not influence the low-level output signals of the D trigger module and the D latch module, and the PWM signal is the basis for the BMS main control chip to judge the charging is finished; when the output end CP of the charging interface of the charging gun does not provide PWM signals any more, the charging is finished; otherwise, if the supply is continued, the charging is not finished.

After step S3, the method further includes the following steps:

step S4: when charging is finished and the charging gun is not pulled out, the CP signal output by the output end CP of the charging interface of the charging gun is changed into 12V from the PWM signal, and at the moment, the control logic strategy for enabling the BMS to automatically sleep by the CP signal is executed, and the control logic strategy specifically comprises the following substeps:

step S40, before BMS dormancy, keeping the charging wake-up signal WKUP output by the D-latch module 400 at a low level, i.e. the WKUP signal is invalid, under the combined action of the D-flip-flop module clear function being valid and the D-latch module high-impedance state output being valid; the charging wakeup self-locking signal PWR output by the BMS master control chip 500 maintains a high level, that is, the PWR signal is valid;

step S41, when the CP signal output by the output CP of the charging interface of the charging gun changes from the PWM signal to the 12V continuous high level signal, the third signal output terminal of the BMS main control chip stops outputting the charging wake-up self-locking signal PWR, that is, the PWR signal changes from the high level to the low level;

step S42, a power supply enabling signal EN output by the switch selection module is changed from high level to low level, so that the power supply module stops outputting power supply and does not supply power to the BMS main control chip any more;

step S43, after the BMS main control chip is powered off, no output signal is input into the D flip-flop module and the D latch module, so that the zero clearing function of the D flip-flop module is changed from effective to ineffective, and the high-impedance state output of the D latch module is changed from effective to ineffective, so that the outputs of the D flip-flop module and the D latch can change along the same direction of the input signal;

in step S44, since the CP signal output from the output CP of the charging interface of the charging gun maintains a high level of 12V, and no rising edge signal jumping from 0V to 12V is input to the clock signal input CLK of the D flip-flop module, the output of the D flip-flop module still maintains a low level, so that the charging wake-up signal WKUP also maintains a low level, thereby locking the BMS main control chip in a power-off state, and thus the BMS sleeps.

Compared with the prior art, the invention provides the wake-up and sleep circuit of the alternating current charging CP signal, which does not use the PWM signal as the trigger signal, realizes the functions of automatically waking up the BMS and automatically sleeping the BMS by the alternating current charging CP signal through the logic combination control of the high and low level changes of the input and output signals of the D flip-flop and the D latch, and has great production practice significance.

In addition, the hardware circuit of the invention has scientific design, electronic components are of common application models, the type selection is easy, additional occupation of system resources of a BMS main control chip is not needed, the occupied space of the circuit board is small, and the design cost is very low;

in addition, the hardware circuit of the invention has low power consumption, the expense of a BMS system is hardly increased, even if the charging gun is not pulled out for a long time, the battery system or the vehicle-mounted storage battery can not consume electric quantity, and the working time required by the vehicle is ensured, therefore, the technical scheme of the invention has strong practical value and market popularization value.

Drawings

Fig. 1 is a block diagram of a wake-up and sleep circuit for an ac charging CP signal according to the present invention;

fig. 2 is a schematic diagram of a specific connection structure of an ac charging CP signal wake-up and sleep circuit according to the present invention.

Detailed Description

In order to make the technical means for realizing the invention easier to understand, the following detailed description of the present application is made in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are merely illustrative of the relevant application and are not limiting of the application. It should be noted that, for convenience of description, only the portions related to the present application are shown in the drawings.

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present application will be described in detail below with reference to the embodiments with reference to the attached drawings.

Referring to fig. 1 and 2, the present invention provides an ac charging CP signal wake-up and sleep circuit, including a 5V constant current module 100, a CP signal conversion module 200, a D flip-flop module 300, a D latch module 400, a BMS main control chip 500, a selection switch module 600, and a power supply module 700, wherein:

the 5V constant current module 100 is respectively connected with the CP signal conversion module 200, the D flip-flop module 300 and the D latch module 400, and is configured to provide continuous 5V dc output for the CP signal conversion module 200, the D flip-flop module 300 and the D latch module 400;

in the invention, in a specific implementation, the input end of the 5V constant-power module 100 is connected to an external constant-

power

12V or 24V power supply.

The CP signal conversion module 200 has two input ends respectively connected to the output end CP of the charging interface of the charging gun and the output end of the 5V normal power module 100, and is configured to convert the CP signal output from the output end CP of the charging interface of the charging gun into a 5V signal, and then input the 5V signal to the clock signal input end CLK of the D flip-flop module 300;

a D flip-flop module 300 having a signal input terminal D1 and a preset input terminal PRE connected to the output terminal of the 5V normal power module 100, respectively, for keeping the signals at the two input terminals always at a high level;

a D flip-flop module 300 having a clear input CLR connected to an output terminal of the BMS main control chip 500, wherein a high and low level state of an input signal of the clear input CLR is controlled by the output terminal of the BMS main control chip 500;

a D flip-flop module 300 having a clock signal input terminal CLK connected to the output terminal of the CP signal conversion module 200, for receiving the 5V signal input by the CP signal conversion module 200, wherein the 5V signal is valid for a rising edge;

a D flip-flop module 300 having an output connected to the input D2 of the D latch module 400 for providing an input signal to the D latch module 400;

it should be noted that, for the D flip-flop module 300, according to the level states of all the input signals (i.e., the 5V signal output by the 5V constant current module 100, the 5V signal output by the CP signal conversion module 200, and the clear control signal output by the BMS main control chip 500), corresponding signals are output, specifically: when the reset input CLR of the D flip-flop module 300 is at a low level, the output of the D flip-flop module 300 is at a low level, which is independent of the signal level states of D1 and CLK; when the reset input CLR of the D flip-flop module 300 is at a high level, when the clock CLK signal output by the CP signal conversion module 200 changes from a low level to a high level, the output of the D flip-flop module is in a state consistent with the level state of the dc output D1 signal output by the 5V constant current module 100, when the D1 signal is at a high level, the output of the D flip-flop module is at a high level, and otherwise, the output of the D flip-flop module is at a low level.

A D latch module 400 having a latch enable input terminal LEN connected to an output terminal of the 5V constant current module 100, and always keeping an input signal at a high level;

a D latch module 400 having an output enable input terminal OEN connected to an output terminal of the BMS main control chip 500, the high and low level states of the output enable input terminal OEN being controlled by the output of the BMS main control chip 500, for receiving an output state control signal output from the BMS main control chip 500;

a D latch module 400 having an input terminal D2 connected to the output terminal of the D flip-flop module 400 for receiving the output signal of the D flip-flop module 300;

a D-latch module 400 having an output terminal connected to the input terminal of the selection switch module 600, and configured to input a charging wake-up signal WKUP to the selection switch module 600;

it should be noted that, the D-latch module 400 determines whether to output the charging wake-up signal WKUP according to the level states of all the input signals (i.e., the 5V signal output by the 5V constant current module 100, the output signal of the D-flip-flop module 400, and the output state control signal output by the BMS main control chip 500), specifically: when the output enable input terminal OEN of the D latch module 400 is at a low level, the output terminal of the D latch module 400 is at a low level, and the charging wake-up signal WKUP is not output, which is independent of the signal level state input from the input terminal D2 of the D latch module 400; when the output enable input terminal OEN of the D latch module 400 is at a high level, the output terminal of the D latch module 400 is in a same level state as the D2 signal inputted from the input terminal D2 of the D latch module 400, when the D2 signal inputted from the input terminal D2 of the D latch module 400 is at a high level, the charging wake-up signal WKUP is outputted in a high level, and when the D2 signal inputted from the input terminal D2 of the D latch module 400 is at a low level, the charging wake-up signal WKUP is not outputted.

The BMS main control chip 500 comprises three signal output ends, wherein a first signal output end of the BMS main control chip is connected with a reset input end CLR of the D flip-flop module 300 and is used for providing a reset control signal for the D flip-flop module 300 and controlling the high-low level state of a reset input end CLR input signal of the D flip-flop module 300;

the BMS main control chip 500 has a second signal output terminal connected to the output enable input terminal OEN of the D latch module 400 for providing an output state control signal to the D latch module 400, thereby controlling a high-low level state of the output enable input terminal OEN input signal of the D latch module 400;

a third signal output end of the BMS main control chip 500 is connected to an input end of the selection switch module 600, and is configured to provide a charging wake-up self-locking signal PWR for the selection switch module 600;

in addition, the BMS main control chip 500 has a power input DVDD connected to an output terminal of the power module 700 for receiving the dc power output from the power module 700;

the BMS main control chip 500 has a PWM input terminal connected to the output terminal CP of the charging gun charging interface for detecting a PWM signal provided from the output terminal CP of the charging gun charging interface and determining whether charging is finished, wherein when the output terminal CP of the charging gun charging interface does not provide any PWM signal any more, it indicates that charging is finished; otherwise, if the supply is continued, the charging is not finished.

A selector switch module 600 comprising two signal inputs for implementing an or logic function;

a first signal input end of the selection switch module 600 is connected to an output end of the D latch module 400, and is configured to receive a charging wake-up signal WKUP input by the D latch module 400;

a second signal input end of the selection switch module 600 is connected to the output of the BMS main control chip 500, and is configured to receive a charging wake-up self-locking signal PWR output by the BMS main control chip 500;

the output end of the selection switch module 600 is connected to the power enable input end EN of the power module 700, and is configured to provide a power enable signal EN for the power module 700, so as to control the on/off of the power output of the power module 700;

it should be noted that, the selection switch module 600 determines whether to output the power enable signal EN according to the high-low level state of the charge wake-up signal WKUP and the charge wake-up self-locking signal PWR, and specifically includes: when the charging wake-up self-locking signal PWR output by the BMS main control chip 500 is at a high level, the power enable signal EN output by the selection switch module 600 is also at a high level, regardless of the level state of the charging signal wake-up signal WKUP; when the charging wake-up self-locking signal PWR output by the BMS main control chip 500 is at a low level, if the charging signal wake-up signal WKUP input by the D latch module 400 is at a high level, the power enable signal EN output by the selection switch module 600 is also at a high level, and if the charging signal wake-up signal WKUP input by the D latch module 400 is at a low level, the power enable signal EN output by the selection switch module 600 is also at a low level.

A power module 700 having a power output enable input terminal EN connected to the output terminal of the selection switch module 600, and configured to receive a power enable signal EN output by the selection switch module 600, where a high-low level state of the power enable signal EN controls whether the power module 700 outputs a dc power;

it should be noted that, when the power enable signal EN output by the selection switch module 600 is at a high level, the power module 700 outputs the dc power, and when the power enable signal EN is at a low level, the output of the dc power is stopped.

The output terminal of the power module 700 is connected to the power input terminal DVDD of the BMS main control chip 500, and when the power module 700 outputs a dc power, the power module 700 supplies power to the BMS main control chip 500 to wake up the BMS, and when the power module 700 does not output a dc power, the power module stops supplying power to the BMS main control chip 500 to make the BMS sleep.

In the invention, it should be noted that the charging gun is a charging gun on an existing automobile charging pile. As described in the background section, the charging gun is not pulled out after charging is completed, and the charging gun always maintains 12V voltage for a charging wake up CP (CP, i.e., charging wake up) signal of the battery management system BMS, so that the battery management system BMS cannot enter a low power consumption sleep state but continues to maintain a high power consumption normal operation state. At this time, if the battery management system BMS is powered by the on-vehicle DC/DC power source (supplied with power from the battery system), the DC/DC power source consumes the power of the battery system by continuously supplying power to the battery management system BMS; if the battery management system BMS is powered by the on-board battery cell, the battery management system BMS will always consume the on-board battery cell.

In the concrete implementation, the charging gun is a charging pile on any electric vehicle conduction charging system (namely, a charging pile) which meets the national standard GBT18487.1-2015 part 1 general requirements of electric vehicle conduction charging systems of the people's republic of China.

In the present invention, in terms of specific implementation, referring to fig. 2, the CP signal conversion module 200 includes a switch K1, a switch K2, a resistor R15, a resistor R16, and a resistor R17, where:

one end of the switch K1 is connected with the 2 nd pin of the resistor R15;

the other end of the switch K1 is connected with a ground end GND;

one end of the switch K2 is connected with the output end of the 5V constant-current module 100;

the 2 nd pin of the resistor R17 is connected to the ground GND.

It should be noted that the switches K1 and K2 may alternatively use MOSFETs, triodes or opto-couplers for converting the input CP signal into an edge trigger signal acceptable by the D flip-flop module 300.

It should be noted that, when the input end of the CP signal conversion module 200 is not connected to the output end CP of the charging gun charging interface, the CP signal is 0V, so that both the switch K1 and the switch K2 are turned off, and the signal of the 1 st pin of the resistor R17 is at a low level, that is, the output of the CP signal conversion module 200 is at a low level. When the output end CP of the charging interface of the charging gun is connected, the input signal CP of the CP signal conversion module 200 jumps from low level to high level (12V), so that the switches K1 and K2 are turned on, the 5V output of the 5V constant current module is turned on, the signal of the 1 st pin of the resistor R17 jumps from low level to high level, that is, the output of the CP signal conversion module 200 is high level.

In the present invention, in terms of specific implementation, referring to fig. 2, the D flip-flop module 300 includes a D flip-flop and a zero clearing control circuit, and the D flip-flop is connected to the zero clearing control circuit;

the D flip-flop is edge (rising edge active) triggered and has preset and zero clearing functions, and the zero clearing control circuit is connected to the first signal output end of the BMS main control chip 500 and is configured to receive a zero clearing control signal output by the BMS main control chip 500, so as to control whether the zero clearing function of the D flip-flop is active.

In a specific implementation, the D flip-flop module 300 includes a D flip-flop, a resistor R1, a resistor R2, a resistor R3, a resistor R8, and a zero clearing control circuit, where:

the zero clearing control circuit comprises resistors R4, R5, R6 and R7 and an enhanced N-channel field effect transistor (NMOS transistor) Q1;

preset input terminal of D flip-flop

The end of the second pin is connected with the No. 2 pin of the resistor R2;

reset input terminal of D trigger

The 1 st pin of the resistor R5 is connected;

a clock signal input end CLK of the D flip-flop is connected with the output end of the CP signal conversion module 200;

the 2 nd pin of the resistor R9 is connected with the ground terminal GND;

a 2 nd pin of the resistor R6 is connected to a third signal output terminal (i.e., a PWR output terminal) of the BMS main control chip 500.

It should be noted that, referring to fig. 2, for the D flip-flop module 300, the input terminal D of the D flip-flop and the preset enable input terminal D

And a power supply input end VCC is connected to the output of the 5V constant power module 100 through resistors R3, R2 and R1 respectively, and keeps 5V high level all the time; the latch input enable end LE and the power supply input end VCC of the D latch are respectively connected to the output of the 5V constant power module 100 through resistors R10 and R11, and the output is always kept at a 5V high level.

In the D flip-flop module 300, in the zero clearing control circuit, if the no PWR signal is input to the 2 nd pin of the resistor R6, the resistor R7 turns on the gate of the NMOS transistor Q1 with the power ground, and pulls down the gate voltage of the NMOS transistor Q1 to a low level, so that the NMOS transistor Q1 is in an off state; the resistor R4 and the resistor R5 enable the zero clearing input end of the D trigger to be connected with the input end of the D trigger

Is connected with the output end of the 5V constant current module 100 and maintains the zero clearing input end of the D trigger

And 5V high level, and the zero clearing function of the D trigger is invalid. If a PWR signal (high level) is input to the 2 nd pin of the resistor R6, the NMOS transistor Q1 is turned on, the 2 nd pin of the resistor R5 and the 2 nd pin of the resistor R4 are connected to a ground GND, and the resistor R5 connects a zero clearing input terminal of the D flip-flop to GND

And the D flip-flop is connected with a ground end GND and maintains low level, so that the zero clearing function of the D flip-flop is effective, and the output of the D flip-flop is locked to be low level without being influenced by a clock input signal CLK.

It should be noted that, for the D flip-flop module 300, when the D flip-flop zero clearing function is invalid, and when the clock signal input terminal CLK of the D flip-flop does not have a rising edge signal, the output terminal Q of the D flip-flop is connected to the ground terminal GND through the resistor R8 and the resistor R9, so as to maintain the output signal at a low level; when the clock signal input end CLK of the D trigger has a rising edge signal, the output end Q outputs high level.

In the present invention, in terms of specific implementation, referring to fig. 2, the D latch module 400 includes a D latch and an output control circuit, and the D latch is connected to the output control circuit;

the D latch has a tristate gate output function;

the output control circuit is connected to the second signal output terminal of the BMS main control chip 500, and is configured to receive the output enable signal OEN output by the BMS main control chip 500, thereby controlling the D latch to output a corresponding level signal according to the tri-state gate control logic.

In a specific implementation, the D latch module 400 includes a D latch, a resistor R10, a resistor R11, a resistor R14, and an output control circuit;

the output control circuit comprises a resistor R12 and a resistor R13;

output enable input terminal of D latch

the output end Q of the D latch is connected with the 1 st pin of the resistor R14 and the input end of the selection switch module 600;

the 1 st pin of the resistor R10 and the 1 st pin of the resistor R11 are respectively connected with the output end of the 5V constant-current module 100;

the 1 st pin of the resistor R12 is connected with a ground end GND;

the 2 nd pin of the resistor R13 is connected to the 2 nd pin of the resistor R6 and a third signal output terminal (i.e., a PWR output terminal) of the BMS main control chip 500;

the 2 nd pin of the resistor R14 is connected to the ground GND.

It should be noted that, referring to fig. 2, for the D latch module 400, in the output control circuit, when the no PWR signal is input at the 2 nd pin of the resistor R13, the resistor R12 enables the output of the D latch to be input

Is connected with a power ground GND and maintains the output enable input end

When the input signal of the latch is low level, the high-impedance state output of the D latch is invalid, that is, the output of the D latch changes along with the input signal in the same direction, and the input end D is high level, the charging wake-up signal WKUP output by the output end Q is also high level valid, so that the BMS main control chip 500 can be woken up; when the 2 nd pin of the resistor R13 has the input of the PWR signal (high level), the output of the D latch is enabled to be input

Pulling up to a high level to enable the high-impedance state output of the D latch to be effective, that is, the output end Q output of the D latch is in a high-impedance state, and the output end Q of the D latch is connected with a ground end GND through the resistor R14, so that the charging wake-up signal WKUP output by the output end Q is pulled down to a low level to enable the charging wake-up signal WKUP to be in an invalid state; when the high-impedance state output of the D latch is effective, the charging wake-up signal WKUP is locked into an invalid state without being influenced by the change of the input signal of the input end D of the D latch.

In the present invention, it should be noted that, in terms of specific implementation, the CP signal conversion module 200 may be a coupling circuit formed by a MOSFET or a triode, may be formed by a photocoupler, or may be another circuit structure with similar functions, and is configured to convert an input CP signal into an edge trigger signal acceptable by the D flip-flop module 300.

In the present invention, it should be noted that, in terms of implementation, the selection switch module 600 may selectively use currently commonly used or logic circuits, such as a discrete resistor/diode, or a switch integrated chip, or an existing or logic integrated chip.

In the present invention, it should be noted that, in terms of specific implementation, the power module 700 and the 5V constant power module 100 may use a low-power-consumption and step-down dc power circuit or an integrated power module 700 commonly used at present, such as a linear LDO, a switching power supply, and the like, and the dc power circuit or the integrated power module 700 should have a power output enabling function so as to control the on/off of the power output.

In the present invention, it should be noted that, in terms of specific implementation, the BMS host control chip 500 may use a currently commonly used brand, series and model, such as MC9S12 series of NXP, TC265 series of TC2 series of english-flying rabdosia, and the like, and the model of the BMS host control chip 500 is not within the protection scope of the present invention.

In a specific implementation of the present invention, based on the wake-up and sleep circuit for ac charging CP signals provided by the present invention, the CP signal output by the output CP of the charging gun charging interface can be changed from 0V to a rising edge valid signal of 12V, so as to serve as a BMS wake-up trigger signal (i.e., CP signal), wherein the control logic policy of the circuit for waking up the BMS by the CP signal is as follows:

step S0: before the charging gun is inserted, a CP signal output by an output end CP of a charging interface of the charging gun is 0V, the BMS is in a dormant state, no zero clearing control signal is input into the D trigger module by the BMS main control chip 500, the zero clearing function of the D trigger module 300 is invalid, namely, the output end of the D trigger module 300 is changed along with the input signal in the same direction after a clock signal CLK appears to be a rising edge effective signal, and when the clock signal CLK is invalid, the output of the D trigger module 300 is a low level signal; the BMS main control chip 500 does not output a state control signal to the D latch module 400, so that the high-impedance state output of the D latch module 400 is invalid, that is, the output of the D flip-flop module 300 changes along with the input signal thereof, and the output charging wake-up signal WKUP is a low level signal;

step S1: before the charging gun is inserted and charging is started, the CP signal output by the output end CP of the charging interface of the charging gun jumps from OV to 12V, the rising edge valid signal is input into the clock signal input end CLK of the D flip-flop module 300 through the CP signal conversion module, the output of the D flip-flop module 300 is triggered to change from low level (obtained through the wakeup control logic step S0) to high level, the charging wakeup signal WKUP output by the D latch module 400 is changed from low level (obtained through the wakeup control logic step S0) to high level valid signal, the power enable signal EN output by the selection switch module 600 is changed to high level, the power module 700 is triggered to output power to activate the BMS main control chip 500, and at this time, the BMS is preliminarily woken up but is not allowed to be charged;

step S2: after the BMS is initially awakened, the BMS main control chip 500 outputs a high-level charging awakening self-locking signal PWR to the selection switch module 600, and the power supply enabling signal EN output by the selection switch module 600 continues to maintain the high level, so as to control the power supply module 700 to output power and continuously supply power to the BMS main control chip 500; the BMS main control chip 500 inputs a high-level zero clearing control signal to the D flip-flop module 300, so that the zero clearing function of the D flip-flop module 300 is changed from invalid to valid, that is, the output signal of the D flip-flop module 300 is locked from high level to low level until the zero clearing control signal is cancelled; the BMS main control chip 500 inputs a high-level output state control signal to the D latch module 400, so that the high-impedance output of the D latch is changed from invalid to valid, that is, the charging wake-up signal WKUP output by the D latch module 400 is locked from a high level to a low level until the output state control signal is cancelled; to this end, the BMS is sufficiently awakened and allowed to charge.

In the above-mentioned control logic step S2, the charging wake-up signal WKUP output by the D-latch module 400 is disabled, and only the charging wake-up self-locking signal PWR is enabled, so that the BMS can automatically sleep after the charging is finished.

For the present invention, after step S2, the following control steps are also included:

step S3, when the charging of the charging gun is started, the CP signal output by the output end CP of the charging interface of the charging gun is changed from 12V to a PWM signal until the charging is finished, the rising edge of the PWM signal does not influence the low level output signals of the D trigger module 300 and the D latch module 400, and the PWM signal is the basis for the BMS main control chip 500 to judge the charging is finished; when the output end CP of the charging interface of the charging gun does not provide PWM signals any more, the charging is finished; otherwise, if the supply is continued, the charging is not finished.

For the present invention, after step S3, the following control steps are also included:

step S40, before BMS dormancy, keeping the charging wake-up signal WKUP output by the D-latch module 400 at a low level, i.e. the WKUP signal is invalid, under the combined action of the effective zero clearing function of the D-flip-flop module 300 and the effective high-impedance output of the D-latch module 400; the charging wakeup self-locking signal PWR output by the BMS master control chip 500 maintains a high level, that is, the PWR signal is valid;

step S41, when the CP signal output by the output CP of the charging interface of the charging gun changes from the PWM signal to the 12V continuous high level signal, the third signal output terminal of the BMS main control chip 500 stops outputting the charging wake-up self-locking signal PWR, that is, the PWR signal changes from the high level to the low level;

step S42, the power enable signal EN output by the switch selection module 600 changes from high level to low level, so that the power module 700 stops outputting power and no longer supplies power to the BMS main control chip 500;

step S43, after the BMS host control chip 500 is powered off, no output signal is input to the D flip-flop module 300 and the D latch module 400, so that the clear function of the D flip-flop module 300 is changed from active to inactive, and the high-impedance state output of the D latch module 400 is changed from active to inactive, so that the outputs of the D flip-flop module 300 and the D latch can change along the same direction as the input signal;

in step S44, since the CP signal output from the output CP of the charging interface of the charging gun maintains a high level of 12V and a rising edge signal that does not jump from 0V to 12V is input to the clock signal input CLK of the D flip-flop module 300, the output of the D flip-flop module 300 still maintains a low level, so that the charging wake-up signal WKUP also maintains a low level, thereby locking the BMS main control chip 500 in a power-off state, and thus the BMS sleeps.

It should be noted that, the wake-up and sleep circuit for an ac charging CP signal according to the present invention can be directly applied to the battery management system BMS, and can also be applied to other electronic control systems for controlling the wake-up and sleep of the BMS, or to electronic devices having wake-up and sleep requirements.

In summary, compared with the prior art, the wake-up and sleep circuit for the ac charging CP signal provided by the present invention does not use the PWM signal as the trigger signal, and implements the functions of automatically waking up the BMS by the ac charging CP signal and automatically sleeping the BMS by the logic combination control of the high and low level changes of the input and output signals of the D flip-flop and the D latch, thereby having great production practice significance.

In addition, the hardware circuit of the invention has scientific design, the electronic components are of common application models, the type selection is easy, the system resources of the BMS main control chip 500 are not required to be additionally occupied, the occupied space of the circuit board is small, and the design cost is very low;

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims

1. An AC charging CP signal awakening and sleeping circuit, comprising a 5V constant current module (100), a CP signal conversion module (200), a D flip-flop module (300), a D latch module (400), a BMS main control chip (500), a selection switch module (600) and a power supply module (700), wherein:

the 5V constant-current module (100) is respectively connected with the CP signal conversion module (200), the D flip-flop module (300) and the D latch module (400) and is used for providing continuous 5V direct current output for the CP signal conversion module (200), the D flip-flop module (300) and the D latch module (400);

the CP signal conversion module (200) is provided with two input ends which are respectively connected with the output end CP of the charging gun charging interface and the output end of the 5V constant-current module (100), and is used for converting the CP signal output by the output end CP of the charging gun charging interface into a 5V signal and then inputting the 5V signal into the clock signal input end CLK of the D trigger module (300);

a D trigger module (300) having a signal input terminal D1 and a preset input terminal PRE respectively connected with the output terminal of the 5V constant current module (100);

a D flip-flop module (300) having a reset input CLR connected to an output terminal of the BMS main control chip (500);

a D flip-flop module (300) having a clock signal input terminal CLK connected with the output terminal of the CP signal conversion module (200) for receiving the 5V signal inputted by the CP signal conversion module (200);

a D flip-flop module (300) having an output connected to the input D2 of the D latch module (400) for providing an input signal to the D latch module (400);

a D latch module (400) having a latch enable input terminal LEN connected to an output terminal of the 5V constant current module (100);

a D latch module (400) having an output enable input terminal OEN connected to an output terminal of the BMS main control chip (500) for receiving an output state control signal outputted from the BMS main control chip (500);

a D latch module (400) having an input D2 connected to the output of the D flip-flop module (400) for receiving the output signal of the D flip-flop module (300);

a D latch module (400) having an output terminal connected to the input terminal of the selection switch module (600) for inputting a charging wake-up signal WKUP to the selection switch module (600);

the BMS main control chip (500) comprises three signal output ends, wherein a first signal output end of the BMS main control chip is connected with a clear input end CLR of the D trigger module (300) and is used for providing a clear control signal for the D trigger module (300) and controlling the high-low level state of a CLR input signal of the clear input end of the D trigger module (300);

the BMS master control chip (500) is provided with a second signal output end connected with an output enabling input end OEN of the D latch module (400) and used for providing an output state control signal for the D latch module (400) so as to control the high-low level state of an input signal of the output enabling input end OEN of the D latch module (400);

the BMS main control chip (500) is provided with a third signal output end which is connected with the input end of the selection switch module (600) and used for providing a charging awakening self-locking signal PWR for the selection switch module (600);

in addition, the BMS main control chip (500) has a power input DVDD connected to an output of the power module (700) for receiving the dc power outputted by the power module (700);

the BMS main control chip (500) is provided with a PWM input end which is connected with the output end CP of the charging gun charging interface and is used for detecting a PWM signal provided by the output end CP of the charging gun charging interface and judging whether charging is finished or not;

a selector switch module (600) comprising two signal inputs for implementing an OR logic function;

a first signal input end of the selection switch module (600) is connected with an output end of the D latch module (400) and is used for receiving a charging wake-up signal WKUP input by the D latch module (400);

the second signal input end of the selection switch module (600) is connected with the output of the BMS main control chip (500) and is used for receiving a charging wake-up self-locking signal PWR output by the BMS main control chip (500);

the output end of the selection switch module (600) is connected with a power supply enabling input end EN of the power supply module (700) and is used for providing a power supply enabling signal EN for the power supply module (700) so as to control the on-off of the power supply output of the power supply module (700);

the power supply module (700) is provided with a power supply output enable input end EN, is connected with the output end of the selection switch module (600), and is used for receiving a power supply enable signal EN output by the selection switch module (600), and the high-low level state of the power supply enable signal EN controls whether the power supply module (700) outputs a direct-current power supply or not;

the output end of the power supply module (700) is connected with the power supply input end DVDD of the BMS main control chip (500), when the power supply module (700) outputs the direct current power supply, the power supply module (700) supplies power for the BMS main control chip (500) so as to wake up the BMS of the battery management system, and when the power supply module (700) does not output the direct current power supply, the power supply is stopped for the BMS main control chip (500) so as to enable the BMS to sleep.

2. The ac charging CP signal wake-up and sleep circuit as claimed in claim 1, wherein the input terminal of the 5V constant current module (100) is connected to an external constant current 12V or 24V power source.

3. The ac charging CP signal wake-up and sleep circuit of claim 1, wherein the CP signal conversion module 200 comprises a switch K1, a switch K2, a resistor R15, a resistor R16, and a resistor R17, wherein:

one end of the switch K1 is connected with the 2 nd pin of the resistor R15;

the other end of the switch K1 is connected with a ground end GND;

one end of the switch K2 is connected with the output end of the 5V constant-current module (100);

the 2 nd pin of the resistor R17 is connected to the ground GND.

4. The ac charging CP signal wake-up and sleep circuit of claim 1, wherein the D flip-flop module (300) comprises a D flip-flop and a clear control circuit, the D flip-flop and the clear control circuit being connected;

the D trigger is edge-triggered and has preset and zero clearing functions, and the zero clearing control circuit is connected with a first signal output end of the BMS main control chip (500) and used for receiving a zero clearing control signal output by the BMS main control chip (500) so as to control whether the zero clearing function of the D trigger is effective or not.

5. The ac charging CP signal wake-up and sleep circuit of claim 4, wherein the D flip-flop module (300) comprises a D flip-flop, a resistor R1, a resistor R2, a resistor R3, a resistor R8, and a clear control circuit, wherein:

preset input terminal of D flip-flop

The end of the second pin is connected with the No. 2 pin of the resistor R2;

reset input terminal of D trigger

The 1 st pin of the resistor R5 is connected;

a clock signal input end CLK of the D trigger is connected with an output end of the CP signal conversion module (200);

the 2 nd pin of the resistor R9 is connected with the ground terminal GND;

the 2 nd pin of the resistor R6 is connected to a third signal output terminal of the BMS main control chip (500).

6. The ac charging CP signal wake-up and sleep circuit of claim 1, wherein the D-latch module (400) comprises a D-latch and an output control circuit, the D-latch being connected to the output control circuit;

the D latch has a tristate gate output function;

the output control circuit is connected with a second signal output end of the BMS main control chip (500) and is used for receiving an output enable signal OEN output by the BMS main control chip (500).

7. The wake-up and sleep circuit of an ac charging CP signal according to claim 6, characterized in that the D-latch module (400) comprises a D-latch, a resistor R10, a resistor R11, a resistor R14 and an output control circuit;

the output control circuit comprises a resistor R12 and a resistor R13;

output enable input terminal of D latch

the output end Q of the D latch is connected with the 1 st pin of the resistor R14 and the input end of the selection switch module (600);

the 1 st pin of the resistor R10 and the 1 st pin of the resistor R11 are respectively connected with the output end of the 5V constant-current module (100);

the 1 st pin of the resistor R12 is connected with a ground end GND;

the 2 nd pin of the resistor R13 is respectively connected with the 2 nd pin of the resistor R6 and a third signal output end of the BMS main control chip (500);

the 2 nd pin of the resistor R14 is connected to the ground GND.

8. The wake-up and sleep circuit of an ac charging CP signal according to claim 1, wherein the control logic strategy of the circuit to wake up the battery management system BMS by the CP signal is as follows:

step S0: before the charging gun is inserted, a CP signal output by an output end CP of a charging interface of the charging gun is 0V, the BMS is in a dormant state, no zero clearing control signal is input into the D trigger module by the BMS main control chip (500), so that the zero clearing function of the D trigger module (300) is invalid, namely the output end of the D trigger module (300) is changed in the same direction along with the input signal of the clock signal CLK after the clock signal CLK appears to be a rising edge effective signal, and when the clock signal CLK is invalid, the output of the D trigger module (300) is a low level signal; the BMS main control chip (500) does not output a state control signal to the D latch module (400), so that the high-resistance state output of the D latch module (400) is invalid, namely the output of the D trigger module (300) changes along the same direction of the input signal thereof, and the output charging wake-up signal WKUP is a low-level signal;

step S1: before a charging gun is inserted and charging is started, a CP signal output by an output end CP of a charging interface of the charging gun jumps from OV to 12V, a rising edge effective signal is input into a clock signal input end CLK of a D flip-flop module (300) through a CP signal conversion module (200), the output of the D flip-flop module (300) is triggered to change from low level to high level, a charging wake-up signal WKUP output by a D latch module (400) is changed from low level to high level effective signal, a power supply enable signal EN output by a selection switch module (600) is changed into high level, the power supply module (700) is triggered to output power supply to activate a BMS main control chip (500), and at the moment, the BMS is preliminarily woken up but is not allowed to be charged;

step S2: after the BMS is awakened initially, the BMS main control chip (500) outputs a high-level charging awakening self-locking signal PWR for the selection switch module (600), a power supply enabling signal EN output by the selection switch module (600) keeps on keeping the high level, and the power supply module (700) is controlled to output power supply to continuously supply power to the BMS main control chip (500); the BMS main control chip (500) inputs a high-level zero clearing control signal to the D trigger module (300) to enable the zero clearing function of the D trigger module (300) to be changed from invalid to valid, namely the output signal of the D trigger module (300) is locked from high level to low level until the zero clearing control signal is cancelled; the BMS main control chip (500) inputs a high-level output state control signal to the D latch module (400) to enable the high-resistance state output of the D latch to be changed from invalid to valid, namely, the charging wake-up signal WKUP output by the D latch module (400) is locked from high level to low level until the output state control signal is cancelled; to this end, the BMS is sufficiently awakened and allowed to charge.

9. The ac charging CP signal wake-up and sleep circuit of claim 8, further comprising, after step S2, the following control steps:

step S3, when the charging of the charging gun is started, the CP signal output by the output end CP of the charging interface of the charging gun is changed from 12V to a PWM signal until the charging is finished, the rising edge of the PWM signal does not influence the low-level output signals of the D trigger module (300) and the D latch module (400), and the PWM signal is the basis for the BMS main control chip (500) to judge the charging is finished; when the output end CP of the charging interface of the charging gun does not provide PWM signals any more, the charging is finished; otherwise, if the supply is continued, the charging is not finished.

10. The ac charging CP signal wake-up and sleep circuit of claim 9, further comprising, after step S3, the following control steps:

step S40, before the BMS sleeps, under the combined action of the clearing function of the D flip-flop module (300) being valid and the high impedance output of the D latch module (400) being valid, the charging wake-up signal WKUP output by the D latch module 400 is kept at a low level, i.e. the WKUP signal is invalid; the charging wakeup self-locking signal PWR output by the BMS master control chip 500 maintains a high level, that is, the PWR signal is valid;

step S41, when the CP signal output by the output end CP of the charging interface of the charging gun is changed from the PWM signal to a 12V continuous high level signal, the third signal output end of the BMS main control chip (500) stops outputting the charging awakening self-locking signal PWR, namely, the PWR signal is changed from the high level to the low level;

step S42, a power supply enabling signal EN output by the switch selection module (600) is changed from high level to low level, so that the power supply module (700) stops outputting power supply and does not supply power to the BMS main control chip (500);

step S43, after the BMS main control chip (500) is powered off, no output signal is input into the D flip-flop module (300) and the D latch module (400), so that the zero clearing function of the D flip-flop module (300) is changed from effective to ineffective, and the high-impedance state output of the D latch module (400) is changed from effective to ineffective, so that the outputs of the D flip-flop module (300) and the D latch can change along the same direction of the input signal;

in step S44, since the CP signal output from the output CP of the charging interface of the charging gun maintains a high level of 12V and a rising edge signal that does not jump from 0V to 12V is input to the clock signal input CLK of the D flip-flop module (300), the output of the D flip-flop module (300) is still maintained at a low level, so that the charging wake-up signal WKUP is also maintained at a low level, thereby locking the BMS main control chip (500) in a power-off state, and thus the BMS sleeps.