CN216959371U

CN216959371U - Charging activation circuit and power supply system

Info

Publication number: CN216959371U
Application number: CN202123392380.2U
Authority: CN
Inventors: 徐勇平; 严威; 周云
Original assignee: Icon Energy System Shenzhen co ltd
Current assignee: Icon Energy System Shenzhen co ltd
Priority date: 2021-12-29
Filing date: 2021-12-29
Publication date: 2022-07-12
Anticipated expiration: 2031-12-29

Abstract

The utility model discloses a charging activation circuit and a power supply system, wherein the circuit comprises: the charging and discharging control system comprises a battery, a charging and discharging switching tube, a DC/DC module, a switching circuit and a control chip, wherein the battery is used for supplying power; the input end of the charge and discharge switching tube is connected with the charger, and the output end of the charge and discharge switching tube is connected with the battery; a DC/DC module for activating the battery management system; the first end of the switching circuit is connected with the DC/DC module, the second end of the switching circuit is connected with the battery, the third end of the switching circuit is used for being connected with the charger, and the switching circuit is conducted when being connected with the charger so that the battery supplies power to the DC/DC module; and the control chip is connected with the DC/DC module and the control end of the charge and discharge switching tube and is used for controlling the charge and discharge switching tube to be closed so that the battery is charged by the charger. From this, realized the battery activation of charging under the undervoltage condition, need not manual operation button, automatic activation is more convenient, has reduced the consumption.

Description

Charging activation circuit and power supply system

Technical Field

The utility model relates to the technical field of batteries, in particular to a charging activation circuit and a power supply system.

Background

Energy storage batteries on the market at present can enter a dormant state or a shutdown state after being undervoltage. If the battery is not charged for a long time, the battery cell may be permanently disabled due to self power consumption. In order to solve the problem that the battery cannot be activated due to the undervoltage entering into the sleep state, two solutions are generally available at present. One solution is that if the battery is turned off under voltage, the client needs to manually press a button switch of the battery to turn on the battery so as to close a charging and discharging MOS tube for charging, but the solution brings inconvenience to the client. Another scheme may be to turn on a Battery Management System (BMS) through a Power Conversion System (PCS) control or remote control, but this scheme needs to communicate with the BMS, i.e., the BMS needs to be in an operating state, which increases the Power consumption of the Battery in an undervoltage state, and is not suitable.

SUMMERY OF THE UTILITY MODEL

The utility model provides a charging activation circuit and a power supply system, and aims to solve the problems that manual operation is needed when a battery is under-voltage and enters a dormant state to be reactivated, and the battery is complicated and inconvenient.

In a first aspect, the present invention provides a charge activation circuit, including: the device comprises a battery, a charging and discharging switching tube, a DC/DC module, a switching circuit, a control chip and a battery; the input end of the charge and discharge switching tube is connected with the charger, and the output end of the charge and discharge switching tube is connected with the battery; a DC/DC module for activating the battery management system; the first end of the switching circuit is connected with the DC/DC module, the second end of the switching circuit is connected with the battery, the third end of the switching circuit is used for being connected with the charger, and the switching circuit is conducted when being connected with the charger so that the battery supplies power to the DC/DC module; and the control chip is connected with the DC/DC module and the control end of the charge and discharge switching tube and is used for controlling the charge and discharge switching tube to be closed so that the battery is charged by the charger.

Further, the switch circuit comprises a first switch unit and a second switch unit, the first switch unit is used for connecting the charger, the input end of the second switch unit is connected with the battery, the output end of the second switch unit is connected with the control end of the second switch unit connected with the DC/DC module, and the first switch unit is used for controlling the conduction of the second switch unit when being connected with the charger.

Further, the first switch unit comprises a third triode, a second MOS transistor, a sixth MOS transistor, a fourth resistor, a fifth resistor, a sixth resistor, a tenth resistor and a first voltage-stabilizing subunit, the source electrode of the sixth MOS tube is used for connecting the charger, the drain electrode of the sixth MOS tube is connected with the collector electrode of the third triode through the sixth resistor, the grid electrode of the sixth MOS tube is connected with the base electrode of the third triode through the tenth resistor, the first voltage-stabilizing subunit is connected between the source electrode and the grid electrode of the sixth MOS tube, the base electrode of the third triode is grounded through a fifth resistor, the emitter of the third triode is grounded through a fourth resistor, the grid electrode of the second MOS tube is connected with the emitter of the third triode, the drain electrode of the second MOS tube is connected with the control end of the second switch unit, and the source electrode of the second MOS tube is grounded.

Further, the second switch unit includes a first MOS transistor, a second resistor, and a second voltage-stabilizing subunit, a source of the first MOS transistor is connected to the battery, a drain of the first MOS transistor is connected to the DC/DC module, a gate of the first MOS transistor is connected to a drain of the second MOS transistor through the second resistor, and the second voltage-stabilizing subunit is connected between the source and the gate of the first MOS transistor.

Further, the charging activation circuit further comprises a cut-off unit, the cut-off unit is connected with the first switch unit and the control chip, and the cut-off unit is used for receiving a cut-off signal output by the control chip and cutting off the first switch unit.

Further, the cut-off unit comprises a seventh MOS transistor and a thirteenth resistor, the control chip is connected to the gate of the seventh MOS transistor through the thirteenth resistor, the drain of the seventh MOS transistor is connected to the base of the third triode, and the source of the seventh MOS transistor is grounded.

Furthermore, the charging activation circuit further comprises an overvoltage protection unit, one end of the overvoltage protection unit is used for being connected with the charger, the other end of the overvoltage protection unit is connected with the cut-off unit, and the overvoltage protection unit is used for controlling the cut-off unit to disconnect the first switch unit when the charging voltage is too high.

Further, the overvoltage protection unit comprises an eighth triode, a fifth voltage regulator tube, a sixth diode, an eighth resistor, a ninth resistor, an eleventh resistor and a fourteenth resistor, the eighth resistor and the eleventh resistor are connected in series, the eighth resistor is used for connecting the charger, the cathode of the fifth voltage-regulator tube is connected with the eleventh resistor, the anode of the fifth voltage-regulator tube is grounded, the base electrode of the eighth triode is connected between the eighth resistor and the eleventh resistor, the emitter electrode of the eighth triode is connected with the charger through the ninth resistor, the collector of the eighth triode is grounded through the fourteenth resistor, the anode of the sixth diode is connected between the fourteenth resistor and the collector of the eighth triode, and the cathode of the sixth diode is connected with the thirteenth resistor.

Further, the charging activation circuit further comprises a signal judgment unit, the signal judgment unit comprises a ninth MOS transistor, a sixteenth resistor, a seventeenth resistor, an eighteenth resistor and a third voltage stabilization subunit, a drain electrode of the ninth MOS transistor is connected to the power pin of the control chip through the sixteenth resistor, a gate of the ninth MOS transistor is connected to an emitter of the third triode through the eighteenth resistor, a source electrode of the ninth MOS transistor is connected to the voltage feedback pin of the control chip through the seventeenth resistor, the third voltage stabilization subunit is connected between the gate and the source electrode of the ninth MOS transistor, and the source electrode of the ninth MOS transistor is grounded.

In a second aspect, the present invention further provides a power supply system, including a charging activation circuit and a battery management system, where the charging activation circuit is the charging activation circuit of the first aspect, and the charging activation circuit is used to activate the battery management system.

Compared with the prior art, the utility model has the beneficial effects that: the charger is connected with the battery through the switch circuit, when the charger is connected with the switch circuit, the switch circuit is conducted to enable the battery to supply power to the DC/DC module, the DC/DC module activates the battery management system, the DC/DC module supplies power to the control chip after being electrified, the control chip outputs a control signal to control the charging and discharging switch tube to be closed, the charger normally charges the battery, therefore, the charging activation of the battery in an undervoltage state is achieved, a manual operation button is not needed, the automatic activation is more convenient, and the power consumption is reduced.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 shows a schematic diagram of a charge activation circuit according to an embodiment of the utility model;

FIG. 2 shows a schematic diagram of a charge activation circuit according to another embodiment of the present invention;

FIG. 3 shows a circuit diagram of a charge activation circuit according to an embodiment of the utility model;

FIG. 4 is a circuit diagram of a signal determining unit of the charge pump circuit according to an embodiment of the present invention;

10. a battery; 20. a charge and discharge switch tube; 30. a DC/DC module; 40. a switching circuit; 41. a first switch unit; 42. a second switching unit; 50. a control chip; 60. a cutting unit; 70. an overvoltage protection unit; 80. a signal judgment unit; 90. a charger.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It will be understood that the terms "comprises" and/or "comprising," when used in this specification and the appended claims, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

It is also to be understood that the terminology used in the description of the utility model herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used in the specification of the present invention and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

It should be further understood that the term "and/or" as used in this specification and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

Referring to fig. 1, an embodiment of the present invention provides a charge activation circuit, including: the device comprises a battery 10, a charging and discharging switching tube 20, a DC/DC module 30, a switching circuit 40 and a control chip 50(MCU), wherein the battery 10 is used for supplying power; the input end of the charge and discharge switching tube 20 is connected with a charger, and the output end of the charge and discharge switching tube is connected with the battery 10; a DC/DC module 30 for activating a battery 10 management system; a switch circuit 40, having a first terminal connected to the DC/DC module 30, a second terminal connected to the battery 10, and a third terminal connected to the charger, wherein the switch circuit 40 is turned on when connected to the charger, so that the battery 10 supplies power to the DC/DC module 30; and the control chip 50 is connected with the DC/DC module 30 and the control end of the charge and discharge switching tube 20, and the control chip 50 is used for controlling the charge and discharge switching tube 20 to be closed so that the charger charges the battery 10.

Specifically, the charge activation circuit has P + and P-for connecting the charger, and B + and B-, where the voltages of P + and P-are the charger voltages, and B + and B-are for connecting the battery 10. The charge and discharge switching tube 20 is located between P + and B +, and the charger can normally charge the battery 10 when closed, and is disconnected to charge the battery 10. B-is common to P-. The switch circuit 40 is located between B + and B-, the switch circuit 40 includes a first terminal, a second terminal and a third terminal, the first terminal is connected to P + and the charging and discharging switch tube 20 directly, the second terminal is connected to B +, and the third terminal is connected to the DC/DC module 30. The DC/DC module 30 is connected to a battery 10 management system, and the DC/DC module 30 supplies power to the battery 10 management system when being powered on, thereby activating the battery 10 management system. The control chip 50 is connected to the control terminal of the switch circuit 40, and the control chip 50 controls the charging and discharging switch tube 20 to be closed by outputting a high level or a low level.

Through implementing the embodiment, the switch circuit 40 is set to connect the charger, the battery 10 and the DC/DC module 30, when the charger is connected to the switch circuit 40, the switch circuit 40 is turned on to supply power to the DC/DC module 30 by the battery 10, thereby activating the management system of the battery 10 by the DC/DC module 30, the DC/DC module 30 supplies power to the control chip 50 after being powered on, the control chip 50 outputs a control signal to control the charging and discharging switch tube 20 to be closed, so that the charger normally charges the battery 10, therefore, the charging activation of the battery 10 in a shutdown state is realized, a manual operation button is not needed, the automatic activation is more convenient, and the power consumption is reduced.

Referring to fig. 2, in an embodiment, the switching circuit 40 includes a first switching unit 41 and a second switching unit 42, the first switching unit 41 is used for connecting the charger, an input terminal of the second switching unit 42 is connected to the battery 10, an output terminal of the second switching unit 42 is connected to the DC/DC module 30, a control terminal of the second switching unit 42 is connected to the first switching unit 41, and the first switching unit 41 is used for controlling the second switching unit 42 to be turned on when the charger is connected. It should be noted that the first switch unit 41 and the second switch unit 42 in the embodiment have various forms, such as a transistor, a MOS transistor, or a switch circuit 40 composed of a plurality of switch elements, as long as the switch function can be achieved, and the utility model is not limited thereto. When charging activation is needed, the charger is connected to the switch circuit 40, the charger provides charging voltage, the first switch unit 41 is driven by the charging voltage to be conducted, the control end of the second switch unit 42 is connected with the first switch unit 41, the second switch unit 42 is controlled by the first switch unit 41, the second switch unit 42 is conducted when the first switch unit 41 is conducted, a path is formed between the battery 10 and the DC/DC module 30, the DC/DC module 30 is supplied with power by the battery 10, and the DC/DC module 30 supplies voltage to a management system of the battery 10 after converting the voltage, so that the management system of the battery 10 is activated. And the DC/DC module 30 supplies power to the control chip 50 after converting the voltage, the control chip 50 outputs a control signal to the control end of the charge-discharge switching tube 20 after being electrified, and the charge-discharge switch is controlled to be closed, so that the charge voltage output by the charger can directly charge the battery 10 through the charge-discharge switching tube 20, the operation of charging activation is completed, manual operation is not needed, the charger only needs to be accessed, convenience and rapidness are realized, and the user experience is good.

Referring to fig. 3, in an embodiment, the first switching unit 41 includes a third transistor Q3, a second MOS transistor Q2, a sixth MOS transistor Q6, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a tenth resistor R10, and a first voltage regulator subunit, a source of the sixth MOS transistor Q2 is used for connecting the charger, a drain of the sixth MOS transistor Q6 is connected to a collector of the third transistor Q3 through the sixth resistor R6, a gate of the sixth MOS transistor Q6 is connected to a base of the third transistor Q3 through the tenth resistor R10, the first voltage regulator subunit is connected between the source and the gate of the sixth MOS transistor Q6, a base of the third transistor Q3 is connected to ground through the fifth resistor R5, an emitter of the third transistor Q3 is connected to ground through the fourth resistor R4, a gate of the second transistor Q2 is connected to an emitter of the third transistor Q3, and a drain of the second transistor Q2 is connected to a control terminal of the second voltage regulator unit, the source of the second MOS transistor Q2 is grounded.

Specifically, the third transistor Q3 is an NPN transistor, the second MOS transistor Q2 is an NMOS transistor, and the sixth MOS transistor Q6 is a PNP transistor. The first voltage-stabilizing subunit comprises a seventh resistor R7 and a fourth voltage-stabilizing tube D4, the seventh resistor R7 is connected with the fourth voltage-stabilizing tube D4 in parallel, the cathode of the fourth voltage-stabilizing tube D4 is connected with the source electrode of the sixth MOS tube Q6, and the anode of the fourth voltage-stabilizing tube D4 is connected with the gate of the sixth MOS tube Q6. The source of the sixth MOS transistor Q6 is connected to P +, and when the charger is connected, the voltage on P + is the charging voltage, that is, when P + P-is powered on, the voltage is divided by the resistor R7R 10R5, a voltage is generated on R10, so that Q6 is turned on, and the function of D4 is to remove the clamp voltage when VGS of Q6 reaches a certain value, thereby preventing MOS damage. Then there is a voltage between R5 and R10 that causes Q3 to turn on, and the emitter of Q3 will have a voltage that turns on Q2. Therefore, after the charger is connected, the whole first switch unit 41 is conducted, the circuit structure is simple, and the reliability is high.

Referring to fig. 3, in an embodiment, the second switching unit 42 includes a first MOS transistor Q1, a second resistor R2, and a second regulator subunit, the source of the first MOS transistor Q1 is connected to the battery 10, the drain of the first MOS transistor Q1 is connected to the DC/DC module 30, the gate of the first MOS transistor Q1 is connected to the drain of the second MOS transistor Q2 through a second resistor R2, and the second regulator subunit is connected between the source and the gate of the first MOS transistor Q1.

Specifically, the first MOS transistor Q1 is a PMOS transistor, the second voltage regulator subunit includes a first voltage regulator transistor D1 and a first resistor R1, the first voltage regulator transistor D1 and the first resistor R1 are connected in parallel, a cathode of the first voltage regulator transistor D1 is connected to a source of the first MOS transistor Q1, and an anode of the first voltage regulator transistor D1 is connected to a gate of the first MOS transistor Q1. The second MOS tube Q2 is conducted, the voltage output by the battery 10 is applied to the second voltage-stabilizing subunit, the first voltage-stabilizing tube D1 is conducted in a reverse breakdown mode, the voltage is clamped to a voltage-stabilizing value by the first voltage-stabilizing tube D1, the voltage of the first resistor R1 is the same as that of the first voltage-stabilizing tube D1 in parallel connection, and the first resistor R1 generates a voltage drop to enable the first MOS tube Q1 to be conducted. Therefore, the first MOS transistor Q1 is controlled by the conduction of the second MOS transistor Q2 to conduct, the battery 10 supplies power to the DC/DC module 30 through the first MOS transistor Q1, and the DC/DC module 30 can activate the battery 10 management system and supply power to the control chip 50.

Referring to fig. 2, in an embodiment, the charging activation circuit further includes a cut-off unit 60, the cut-off unit 60 is connected to the first switch unit 41 and the control chip 50, and the cut-off unit 60 is configured to receive a cut-off signal output by the control chip 50 to turn off the first switch unit 41. Specifically, after the charging and discharging switch 20 is closed, the control chip 50 outputs a cut-off signal to the first switch unit 41, so that the first switch unit 41 is opened, and the battery 10 management system (BMS) continuously supplies power to the first MOS transistor Q1 through other circuits to close the first MOS transistor Q1. The other circuits are peripheral circuits, not shown in the figure, and are not limited herein.

Referring to fig. 3, in a specific implementation, the cut-off unit 60 includes a seventh MOS transistor Q7 and a thirteenth resistor R13, the control chip 50 is connected to the gate of the seventh MOS transistor Q7 through the thirteenth resistor R13, the drain of the seventh MOS transistor Q7 is connected to the base of the third triode Q3, and the source of the seventh MOS transistor Q7 is grounded. Specifically, the seventh MOS transistor Q7 is an NPN transistor, the control chip 50 is connected to the thirteenth resistor R13 through a pin, and the control chip 50 outputs a high level to the gate of the seventh MOS transistor Q7, so as to pull down the base of the third transistor Q3, so that the third transistor Q3 is turned off, and the second MOS transistor Q2 is also turned off. The first MOS transistor Q1 provides voltage to the first MOS transistor Q1 through other circuits by the battery 10 management system.

In this embodiment, when the charger is connected to P + and P-and the charging voltage output by the charger is too low, the voltage applied to the base of the third transistor Q3 does not satisfy the turn-on condition, the third transistor Q3 is turned off, and the whole charging activation circuit does not work.

Referring to fig. 2, in an embodiment, the charging activation circuit further includes an overvoltage protection unit 70, one end of the overvoltage protection unit 70 is used for being connected to the charger, and the other end of the overvoltage protection unit 70 is connected to the cut-off unit 60, and the overvoltage protection unit 70 is used for controlling the cut-off unit 60 to open the first switch unit 41 when the charging voltage is too high. Specifically, when the charger is connected to P + and P-, and the charging voltage output from the charger is too high, the overvoltage protection unit 70 triggers overvoltage protection, and the control cutoff unit 60 turns off the first switching unit 41, so that the entire charging activation circuit does not operate.

Referring to fig. 3, in particular, the overvoltage protection unit 70 includes an eighth triode Q8, a fifth regulator D5, a sixth diode D6, an eighth resistor R8, a ninth resistor R9, an eleventh resistor R11, and a fourteenth resistor R14, the eighth resistor R8 and the eleventh resistor R11 are connected in series, the eighth resistor R8 is used to connect the charger, the cathode of the fifth regulator D5 is connected to the eleventh resistor R11, the anode of the fifth regulator D5 is grounded, the base of the eighth triode Q8 is connected between the eighth resistor R8 and the eleventh resistor R11, the emitter of the eighth triode Q8 is connected to the charger through the ninth resistor R9, the collector of the eighth triode Q8 is grounded through the fourteenth resistor R14, the anode of the sixth diode D6 is connected between the fourteenth resistor R14 and the collector of the eighth triode Q8, the cathode of the sixth diode D6 is connected to the thirteenth resistor R13.

The eighth transistor Q8 is a PNP transistor. When the charger is connected to P + and P-and the charging voltage output by the charger is too high, the charging voltage is greater than the breakdown voltage of the fifth voltage-regulator tube D5, the fifth voltage-regulator tube D5 is conducted in a reverse breakdown mode, and the P + and the P-form a loop, so that the eighth triode Q8 is conducted, the voltage output by the collector of the eighth triode Q8 drives the seventh MOS tube Q7 to be disconnected through the sixth diode D6, the base of the third triode Q3 is pulled low, the third triode Q3 is disconnected, and the whole charging activation circuit does not work.

Referring to fig. 4, in an embodiment, the charging activation circuit further includes a signal determination unit 80, the signal determination unit 80 includes a ninth MOS transistor Q9, a sixteenth resistor R16, a seventeenth resistor R17, an eighteenth resistor R18 and a third voltage regulation subunit, a drain of the ninth MOS transistor Q9 is connected to the power supply pin of the control chip 50 through the sixteenth resistor R16, a gate of the ninth MOS transistor Q9 is connected to an emitter of the third transistor Q3 through the eighteenth resistor R18, a source of the ninth MOS transistor Q9 is connected to the voltage feedback pin of the control chip 50 through the seventeenth resistor R17, the third voltage regulation subunit is connected between the gate and the source of the ninth MOS transistor Q9, and a source of the ninth MOS transistor Q9 is grounded.

Specifically, the signal determination unit 80 is connected between the third transistor Q3 and the second MOS transistor Q2 through a POWER pin. The third voltage-stabilizing subunit comprises an eighth voltage-stabilizing tube D8 and a fifteenth resistor R15, the eighth voltage-stabilizing tube D8 and the fifteenth resistor R15 are connected in parallel, the cathode of the eighth voltage-stabilizing tube D8 is connected with the gate of the ninth MOS tube Q9, and the anode of the eighth voltage-stabilizing tube D8 is connected with the source of the ninth MOS tube Q9 and grounded. In the process of charging activation, the ninth MOS transistor Q9 is turned on, a voltage feedback signal (FB signal) is applied to the voltage feedback pin of the control chip 50 through the seventeenth resistor R17, and the control chip 50 determines to trigger charging activation after receiving the signal.

The operation principle of the present embodiment will be further described below.

The charging activation circuit of the embodiment comprises transistors Q1-Q9, resistors R1-R18, voltage-stabilizing tubes D1-D8, a battery CELL, a B +, B-, P +, P-, DC/DC module, a control chip MCU and the like. When the battery is in an undervoltage state, the charging and discharging MOS Q4 and Q6 are disconnected. The BMS is in a power off state. The MOS Q1 is off and does not supply power to the subsequent stage circuits. And when the battery is shut down under low voltage and the charger is not connected, the two ends of the P + and the P-have no voltage. When the charger is connected, the voltages of P + and P-are the charger voltage. At the moment, the current and the voltage are provided for the Q3 base stage through the voltage division of R7, R10, R4 and R5. Turning Q3 on. The G level of the MOS Q2 outputs more than Vgs turn-on voltage through R6, Q3-Vce and R4, and Q2 is turned on. The voltage is divided by resistors R1 and R2, the output is larger than Vgs conducting voltage, and Q1 is conducted. The DCDC is powered up and the BMS is activated. The MCU controls the MOS Q4 and Q5 to close, and the battery can be charged normally.

And after the charging and discharging MOS is closed, the MCU pin is driven. Q7 is controlled to be high by R13. The B stage of transistor Q3 is pulled low. Q3 is not conductive. The power of P + cannot pass through the transistor Q3, the MOS Q2 is disconnected, and the BMS continuously supplies power to the Q1 through other circuits to enable the MOS Q1 to be closed.

If the voltage of the charger (between P + and P-) is too low, the voltage is divided by R7, R10, R4, R5 and Q3, so that the B level of Q3 does not meet the starting condition, at the moment, Q3 is disconnected, and the whole circuit does not work. If the charger voltage (between P + and P-) is too high, it is greater than the regulated voltage of the regulator tube D5. The voltage regulator tube D5 is operated through R8 and R11. P + and P-form a loop. At this time, the transistor Q8 EB is turned on and the transistor CE is turned on. The C-stage output voltage of the Q8 is divided by the R9, the Q8-CE and the R14, the MOS Q7 is driven to be disconnected by the D6, and the B stage of the triode Q3 is pulled down. At this point Q3 is open and the entire line is inactive.

The charging activation is carried out under the state of disconnecting MOS or shutting down, Q9 can be driven through a pin POWER, and an FB signal is output to judge whether the charging activation is carried out.

The embodiment of the utility model also provides a power supply system, which comprises a charging activation circuit and a battery management system, wherein the charging activation circuit is the charging activation circuit in the embodiment, and the charging activation circuit is used for activating the battery management system. The charging activation circuit has been described in detail in the above embodiments, and is not described in detail here.

Through implementing this embodiment, set up switching circuit connection charger and battery and DC/DC module, connect switching circuit when the charger inserts, switching circuit switches on and makes the battery supply power to DC/DC module, thereby the DC/DC module activates battery management system, the power supply to control chip after the DC/DC module is gone up to the electricity, control chip output control signal control charge-discharge switch tube is closed, make the charger normally charge to the battery, therefore, the activation of charging of battery under the undervoltage state has been realized, need not manual operation button, the loaded down with trivial details step of manual operation has been removed from, automatic activation is more convenient, and for prior art need BMS be in operating condition, this embodiment need not BMS keep operating condition, through DC/DC activation BMS can, thereby the power consumption has been reduced.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the utility model, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.

Claims

1. A charge activation circuit, comprising:

a battery;

the input end of the charge and discharge switching tube is connected with the charger, and the output end of the charge and discharge switching tube is connected with the battery;

a DC/DC module for activating the battery management system;

the first end of the switching circuit is connected with the DC/DC module, the second end of the switching circuit is connected with the battery, the third end of the switching circuit is used for being connected with the charger, and the switching circuit is conducted when being connected with the charger so that the battery supplies power to the DC/DC module;

and the control chip is connected with the DC/DC module and the control end of the charge and discharge switching tube and is used for controlling the charge and discharge switching tube to be closed so that the battery is charged by the charger.

2. The charging activation circuit according to claim 1, wherein the switching circuit comprises a first switching unit and a second switching unit, the first switching unit is configured to be connected to the charger, an input terminal of the second switching unit is connected to the battery, an output terminal of the second switching unit is connected to the DC/DC module, a control terminal of the second switching unit is connected to the first switching unit, and the first switching unit is configured to control the second switching unit to be turned on when being connected to the charger.

3. The charging activation circuit according to claim 2, wherein the first switching unit comprises a third transistor, a second MOS transistor, a sixth MOS transistor, a fourth resistor, a fifth resistor, a sixth resistor, a tenth resistor, and a first regulator unit, a source of the sixth MOS transistor is used for connecting the charger, a drain of the sixth MOS transistor is connected to a collector of the third transistor through the sixth resistor, a gate of the sixth MOS transistor is connected to a base of the third transistor through the tenth resistor, the first regulator unit is connected between the source and the gate of the sixth MOS transistor, the base of the third transistor is grounded through the fifth resistor, an emitter of the third transistor is grounded through the fourth resistor, a gate of the second MOS transistor is connected to an emitter of the third transistor, and a drain of the second MOS transistor is connected to the control terminal of the second switching unit, and the source electrode of the second MOS tube is grounded.

4. The charge activation circuit according to claim 3, wherein the second switching unit comprises a first MOS transistor, a second resistor and a second voltage regulation subunit, the source of the first MOS transistor is connected to the battery, the drain of the first MOS transistor is connected to the DC/DC module, the gate of the first MOS transistor is connected to the drain of the second MOS transistor through the second resistor, and the second voltage regulation subunit is connected between the source and the gate of the first MOS transistor.

5. The charging activation circuit of claim 4, further comprising a cut-off unit, wherein the cut-off unit is connected with the first switch unit and the control chip, and the cut-off unit is configured to receive a cut-off signal output by the control chip to turn off the first switch unit.

6. The charging activation circuit of claim 5, wherein the cut-off unit comprises a seventh MOS transistor and a thirteenth resistor, the control chip is connected to the gate of the seventh MOS transistor through the thirteenth resistor, the drain of the seventh MOS transistor is connected to the base of the third transistor, and the source of the seventh MOS transistor is grounded.

7. The charging activation circuit according to claim 6, further comprising an overvoltage protection unit, one end of the overvoltage protection unit is used for being connected with the charger, the other end of the overvoltage protection unit is connected with the cut-off unit, and the overvoltage protection unit is used for controlling the cut-off unit to disconnect the first switch unit when the charging voltage is too high.

8. The charging activation circuit of claim 7, wherein the over-voltage protection unit comprises an eighth triode, a fifth voltage regulator, a sixth diode, an eighth resistor, a ninth resistor, an eleventh resistor and a fourteenth resistor, the eighth resistor and the eleventh resistor are connected in series, the eighth resistor is used for connecting the charger, the cathode of the fifth voltage-regulator tube is connected with the eleventh resistor, the anode of the fifth voltage-regulator tube is grounded, the base electrode of the eighth triode is connected between the eighth resistor and the eleventh resistor, the emitter electrode of the eighth triode is connected with the charger through the ninth resistor, the collector of the eighth triode is grounded through the fourteenth resistor, the anode of the sixth diode is connected between the fourteenth resistor and the collector of the eighth triode, and the cathode of the sixth diode is connected with the thirteenth resistor.

9. The charging activation circuit according to claim 8, further comprising a signal determination unit, wherein the signal determination unit comprises a ninth MOS transistor, a sixteenth resistor, a seventeenth resistor, an eighteenth resistor and a third voltage regulation subunit, a drain of the ninth MOS transistor is connected to the power pin of the control chip through the sixteenth resistor, a gate of the ninth MOS transistor is connected to the emitter of the third triode through the eighteenth resistor, a source of the ninth MOS transistor is connected to the voltage feedback pin of the control chip through the seventeenth resistor, the third voltage regulation subunit is connected between the gate and the source of the ninth MOS transistor, and the source of the ninth MOS transistor is grounded.

10. A power supply system comprising a charge activation circuit according to any one of claims 1 to 9 and a battery management system, wherein the charge activation circuit is configured to activate the battery management system.