CN113675925A

CN113675925A - Charge and discharge control device, semiconductor chip, battery management system and electric equipment

Info

Publication number: CN113675925A
Application number: CN202110992856.1A
Authority: CN
Inventors: 不公告发明人
Original assignee: Zhuhai Maiju Microelectronics Co Ltd
Current assignee: Zhuhai Maiju Microelectronics Co Ltd
Priority date: 2021-08-27
Filing date: 2021-08-27
Publication date: 2021-11-19

Abstract

The present disclosure provides a charge and discharge control device, including: the charging switch is driven to be conducted when the battery device is charged; a charge switch driver, the charge switch being driven on based on a drive signal of the charge switch driver; a discharge switch, the discharge switch being driven to conduct when the battery device is discharged; a discharge switch driver, the discharge switch being driven to conduct based on a drive signal of the discharge switch driver; and a voltage transformation device for transforming the terminal voltage of the battery device to generate at least a first voltage and a second voltage, the second voltage being less than the first voltage, the charge switch driver generating the drive signal based on the first voltage, and the discharge switch driver generating the drive signal based on the second voltage. The disclosure also provides a semiconductor chip, a battery management system and electric equipment.

Description

Charge and discharge control device, semiconductor chip, battery management system and electric equipment

Technical Field

The present disclosure relates to the field of battery technologies, and in particular, to a charge and discharge control device, a semiconductor chip, a battery management system, and an electric device.

Background

In the prior art, a large number of electric devices (electric vehicles, mobile phones, etc.) use a battery pack (or a battery unit or a battery pack) to provide electric energy, the discharge of the battery pack provides electric energy for a load, and the battery pack also needs to be charged.

During the charging and discharging process of the battery pack, the charging loop and the discharging loop need to be controlled, and in the prior art, field effect transistors are often used as control devices of the charging loop and the discharging loop (to turn on or off the charging loop, and to turn on or off the discharging loop).

However, since the source of the field effect transistor used as the discharge loop is generally connected to the negative voltage of the battery pack/cell (stable), and the source of the field effect transistor used as the charge loop is generally connected to the negative voltage of the battery pack (unstable), the driving circuit of the field effect transistor Vgs used as the discharge loop and the field effect transistor Vgs used as the charge loop in the related art may cause failure of the field effect transistor used as the charge loop.

Disclosure of Invention

In order to solve at least one of the above-described technical problems, the present disclosure provides a new charge and discharge control device, a semiconductor chip, a battery management system, and an electric device.

The charge and discharge control device, the semiconductor chip, the battery management system and the electric equipment are realized by the following technical scheme.

According to an aspect of the present disclosure, there is provided a charge and discharge control device including:

a charging switch, which is driven to be turned on when the battery device is charged;

a charge switch driver, the charge switch being driven on based on a drive signal of the charge switch driver;

a discharge switch that is driven to conduct when the battery device is discharged;

a discharge switch driver, the discharge switch being driven to conduct based on a driving signal of the discharge switch driver; and the number of the first and second groups,

the charging switch driver generates a driving signal based on the first voltage, and the discharging switch driver generates a driving signal based on the second voltage.

According to the charge and discharge control device of at least one embodiment of the present disclosure, the charge switch and the discharge switch are both field effect transistors.

According to the charge and discharge control device of at least one embodiment of the present disclosure, the voltage transformation device includes a charge pump and a voltage buffer, the charge pump transforms a terminal voltage of the battery device to the first voltage, the first voltage is used as a supply voltage of the voltage buffer, and the voltage buffer outputs the second voltage.

According to the charge and discharge control device of at least one embodiment of the present disclosure, the charge pump includes a first switch, a second switch, a third switch, a first capacitor, and a second capacitor, the first switch is disposed between a first end of the first capacitor and a positive terminal of the battery device, the second switch is disposed between a second end of the first capacitor and a negative terminal of the battery device, the third switch is disposed between the second end of the first capacitor and the positive terminal of the battery device, and the second capacitor is disposed between the positive terminal of the battery device and the negative terminal or the ground terminal of the battery device.

According to the charge and discharge control apparatus of at least one embodiment of the present disclosure, the voltage buffer includes an active circuit;

the active circuit comprises a third P-type MOS tube, a fourth P-type MOS tube, a second N-type MOS tube and a first P-type MOS tube, wherein the source terminal of the third P-type MOS tube and the source terminal of the fourth P-type MOS tube are connected with the output voltage of the voltage transformation device;

the grid end of the third P-type MOS tube is connected with the grid end of the fourth P-type MOS tube;

the drain end of the second N-type MOS tube is respectively connected with the drain end and the gate end of the third P-type MOS tube;

the source end of the first P-type MOS tube is connected with the drain end of the fourth P-type MOS tube;

the source end of the second N-type MOS tube is connected with the drain end of the first P-type MOS tube and is grounded;

a grid end of the second N-type MOS tube is applied with bias voltage to conduct the second N-type MOS tube, the third P-type MOS tube and the fourth P-type MOS tube;

the grid end of the first P-type MOS tube is applied with a reference voltage to conduct the first P-type MOS tube, and the reference voltage is raised by using a series resistor and is provided to the source end of the first P-type MOS tube to serve as an output buffer voltage.

According to the charge and discharge control device of at least one embodiment of the present disclosure, the voltage buffer further includes at least one slave circuit that duplicates a voltage of a source terminal of the first P-type MOS transistor of the master circuit as a driving signal of another discharge switch driver.

According to the charge and discharge control device of at least one embodiment of the present disclosure, the slave circuit includes a fifth P-type MOS transistor, a sixth P-type MOS transistor, a first N-type MOS transistor, and a second P-type MOS transistor, and a source terminal of the fifth P-type MOS transistor and a source terminal of the sixth P-type MOS transistor are connected to the output voltage of the voltage transformation device;

the grid end of the fifth P-type MOS tube is connected with the grid end of the sixth P-type MOS tube;

the drain end of the first N-type MOS tube is respectively connected with the drain end and the gate end of the fifth P-type MOS tube;

the source end of the second P-type MOS tube is connected with the drain end of the sixth P-type MOS tube;

the source end of the first N-type MOS tube is connected with the drain end of the second P-type MOS tube and is grounded;

the grid end of the first N-type MOS tube is applied with the bias voltage to conduct the first N-type MOS tube, the fifth P-type MOS tube and the sixth P-type MOS tube;

the reference voltage is applied to the grid end of the second P-type MOS tube to conduct the second P-type MOS tube, and the voltage of the source end of the second P-type MOS tube is used as the output buffer voltage.

According to the charge and discharge control device of at least one embodiment of the present disclosure, the first P-type MOS transistor and the second P-type MOS transistor are the same MOS transistor; the first N-type MOS tube and the second N-type MOS tube are the same MOS tube.

According to the charge and discharge control apparatus of at least one embodiment of the present disclosure, the discharge switch driver includes a driver switching device, and when the driver switching device is turned on, the discharge switch driver applies the buffer voltage to the discharge switch to turn on the discharge switch.

According to the charge and discharge control device of at least one embodiment of the present disclosure, the discharge switch driver includes a first drive control logic device that controls on and off of the driver switching device.

According to the charge and discharge control device of at least one embodiment of the present disclosure, the charge switch driver includes a first current mirror, a second current mirror, and a current source, the current source provides a driving current, the first current mirror mirrors the driving current for the first time, the second current mirror mirrors the driving current mirrored for the first time again to provide the driving current to the bias resistor, so that a voltage across the bias resistor serves as a gate-source control voltage of the charge switch.

According to the charge and discharge control device of at least one embodiment of the present disclosure, the charge switch driver further includes a second drive control logic device that controls the current source such that the current source outputs or does not output the drive current.

According to the charge and discharge control device of at least one embodiment of the present disclosure, a protection diode is provided between the gate and the source of the charge switch.

The charge and discharge control device according to at least one embodiment of the present disclosure further includes a current detection resistor to detect a charge current of the battery during charge and a discharge current of the battery during discharge.

According to the charge and discharge control device of at least one embodiment of the present disclosure, the charge and discharge control device is in the form of a semiconductor chip.

According to another aspect of the present disclosure, there is provided a semiconductor chip formed with the charge and discharge control device according to any one of the above.

According to still another aspect of the present disclosure, there is provided a battery management system including:

the charge/discharge control device according to any one of the above, wherein the charge/discharge control device controls charge/discharge of the battery device.

According to still another aspect of the present disclosure, there is provided an electric device including:

a battery device; and the number of the first and second groups,

in the above battery management system, the battery management system controls at least charging/discharging of the battery device.

Drawings

The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the disclosure and together with the description serve to explain the principles of the disclosure.

Fig. 1 is a schematic circuit configuration diagram of a charge and discharge control device according to an embodiment of the present disclosure.

Fig. 2 is a schematic circuit configuration diagram of a charge pump of the charge and discharge control device according to an embodiment of the present disclosure.

Fig. 3 and 4 are schematic diagrams of a first operating state and a second operating state, respectively, of the charge pump shown in fig. 2.

Fig. 5 is a schematic circuit configuration diagram of a voltage transformation device of a charge and discharge control device according to an embodiment of the present disclosure.

Fig. 6 is a schematic circuit configuration diagram of a charge switch driver of a charge and discharge control device according to an embodiment of the present disclosure.

Fig. 7 is a schematic circuit configuration diagram of a discharge switch driver of a charge and discharge control device according to an embodiment of the present disclosure.

Fig. 8 is a block diagram illustrating a structure of an electric device according to an embodiment of the present disclosure.

Description of the reference numerals

10 charge and discharge control device

20 battery device

101 charging switch

102 discharge switch

103 charging switch driver

104 discharge switch driver

105 voltage transformation device

201 battery unit

1031 first current mirror

1032 second current mirror.

Detailed Description

The present disclosure will be described in further detail with reference to the drawings and embodiments. It is to be understood that the specific embodiments described herein are for purposes of illustration only and are not to be construed as limitations of the present disclosure. It should be further noted that, for the convenience of description, only the portions relevant to the present disclosure are shown in the drawings.

It should be noted that the embodiments and features of the embodiments in the present disclosure may be combined with each other without conflict. Technical solutions of the present disclosure will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.

Unless otherwise indicated, the illustrated exemplary embodiments/examples are to be understood as providing exemplary features of various details of some ways in which the technical concepts of the present disclosure may be practiced. Accordingly, unless otherwise indicated, features of the various embodiments may be additionally combined, separated, interchanged, and/or rearranged without departing from the technical concept of the present disclosure.

The use of cross-hatching and/or shading in the drawings is generally used to clarify the boundaries between adjacent components. As such, unless otherwise noted, the presence or absence of cross-hatching or shading does not convey or indicate any preference or requirement for a particular material, material property, size, proportion, commonality between the illustrated components and/or any other characteristic, attribute, property, etc., of a component. Further, in the drawings, the size and relative sizes of components may be exaggerated for clarity and/or descriptive purposes. While example embodiments may be practiced differently, the specific process sequence may be performed in a different order than that described. For example, two processes described consecutively may be performed substantially simultaneously or in reverse order to that described. In addition, like reference numerals denote like parts.

When an element is referred to as being "on" or "on," "connected to" or "coupled to" another element, it can be directly on, connected or coupled to the other element or intervening elements may be present. However, when an element is referred to as being "directly on," "directly connected to" or "directly coupled to" another element, there are no intervening elements present. For purposes of this disclosure, the term "connected" may refer to physically, electrically, etc., and may or may not have intermediate components.

For descriptive purposes, the present disclosure may use spatially relative terms such as "below … …," below … …, "" below … …, "" below, "" above … …, "" above, "" … …, "" higher, "and" side (e.g., "in the sidewall") to describe one component's relationship to another (other) component as illustrated in the figures. Spatially relative terms are intended to encompass different orientations of the device in use, operation, and/or manufacture in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" the other elements or features. Thus, the exemplary term "below … …" can encompass both an orientation of "above" and "below". Further, the devices may be otherwise positioned (e.g., rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. Furthermore, when the terms "comprises" and/or "comprising" and variations thereof are used in this specification, the presence of stated features, integers, steps, operations, elements, components and/or groups thereof are stated but does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and/or groups thereof. It is also noted that, as used herein, the terms "substantially," "about," and other similar terms are used as approximate terms and not as degree terms, and as such, are used to interpret inherent deviations in measured values, calculated values, and/or provided values that would be recognized by one of ordinary skill in the art.

The charge/discharge control device, the semiconductor chip, the battery management system, and the electric device according to the present disclosure will be described in detail below with reference to fig. 1 to 8.

Fig. 1 is a circuit configuration diagram of a charge/discharge control device according to an embodiment of the present disclosure.

The battery device 20 shown in fig. 1 includes one battery unit 201, and it should be noted that the battery device 20 may be in the form of a battery pack, that is, the battery device 20 includes a plurality of battery units 201 connected in series. The battery unit 201 may be a lithium battery, or may be other types of batteries.

According to an embodiment of the present disclosure, referring to fig. 1, a charge and discharge control device 10 includes:

a charging switch 101, wherein the charging switch 101 is driven to be turned on when the battery device 20 is charged;

a charge switch driver 103, the charge switch 101 being driven on based on a drive signal of the charge switch driver 103;

a discharge switch 102, wherein when the battery device 20 discharges, the discharge switch 102 is driven to be on;

a discharge switch driver 104, the discharge switch 102 being driven to be on based on a drive signal of the discharge switch driver 104; and the number of the first and second groups,

and a voltage transformation device 105, wherein the voltage transformation device 105 transforms a terminal voltage of the battery device 20 to generate at least a first voltage and a second voltage, the second voltage being smaller than the first voltage, the charge switch driver 103 generates a drive signal based on the first voltage, and the discharge switch driver 104 generates a drive signal based on the second voltage.

The voltage transformation device 105 of the present disclosure may output a corresponding first voltage (Vcp1) and second voltage (Vbuf) based on the magnitude of the terminal voltage of the battery device 20 to meet the requirements of the charging switch driver 103 and the discharging switch driver 104.

In the charge/discharge control device 10 according to the above embodiment, the charge switch 101 and the discharge switch 102 are both field effect transistors.

Fig. 1 exemplarily shows the structures of the field effect transistors of the charge switch 101 and the discharge switch 102, and those skilled in the art can adjust the structures (channel type, etc.) of the charge switch 101 and the discharge switch 102 in light of the technical solution of the present disclosure.

With the charge-discharge control device 10 of each of the above embodiments, preferably, the voltage transformation device 105 includes a charge pump (CP1) and a voltage buffer, the charge pump (CP1) transforms the terminal voltage of the battery device 20 to a first voltage (Vcp1), the first voltage (Vcp1) is used as a power supply voltage (Vcp1) of the voltage buffer, and the voltage buffer outputs the second voltage (Vbuf).

With the charge-discharge control device 10 of each of the above embodiments, the charge pump (CP1) preferably includes the first switch (SW1), the second switch (SW2), the third switch (SW3), and the first capacitor (C)_FLY1) And a second capacitance (C)_B1) The first switch (SW1) is arranged on the first capacitor (C)_FLY1) And the positive terminal of the battery device 20, and a second switch (SW2) is provided in the first capacitor (C)_FLY1) And a negative terminal of the battery device 20, and a third switch (SW3) is provided in the first capacitor (C)_FLY1) And the positive terminal of the battery device 20, a second capacitor (C)_B1) Is provided between the positive terminal of the battery device 20 and the negative or ground terminal of the battery device 20.

Fig. 2 shows a circuit configuration of a charge pump according to an embodiment of the present disclosure, which increases the terminal voltage of the battery device 20 to 2 times the terminal voltage, that is, Vcp1 is 2 × Vbat +, it should be understood by those skilled in the art that, when the battery device 20 is a battery pack formed by a plurality of battery cells 201 connected in series, the charge pump may adopt a charge pump or a transformer having a voltage reduction function in the prior art to convert the terminal voltage of the battery device 20 to a desired first voltage.

Fig. 3 to 4 illustrate the operation principle of the charge pump according to one embodiment of the present disclosure, as shown in fig. 3, in the first half of the duty cycle, when the first switch (SW1) and the second switch (SW2) are closed and the third switch (SW3) is open, the first capacitor (C) is connected_FLY1) Accumulated charge, first capacitance (C)_FLY1) The voltage at the first terminal of (1) rises to Vbat +; in the second half of the duty cycle, as shown in FIG. 4, the first switch (SW1) and the second switch (SW2) are open, the third switch (SW3) is closed, and the first capacitor (C)_FLY1) The voltage of the first terminal of (a) rises to 2 × Vbat +.

With the charge-discharge control device 10 of each of the above embodiments, it is preferable that the voltage buffer includes the active circuit (a).

Referring to fig. 5, the active circuit (a) includes a third P-type MOS transistor (MP3), a fourth P-type MOS transistor (MP4), a second N-type MOS transistor (MN2), and a first P-type MOS transistor (MP1), wherein a source terminal of the third P-type MOS transistor (MP3) and a source terminal of the fourth P-type MOS transistor (MP4) are connected to the output voltage (Vcp1) of the voltage transformation device 105;

the grid end of the third P-type MOS tube (MP3) is connected with the grid end of the fourth P-type MOS tube (MP 4);

the drain end of the second N-type MOS tube (MN2) is respectively connected with the drain end and the gate end of the third P-type MOS tube (MP 3);

the source end of the first P-type MOS tube (MP1) is connected with the drain end of the fourth P-type MOS tube (MP 4);

the source terminal of the second N-type MOS transistor (MN2) is connected with the drain terminal of the first P-type MOS transistor (MP1) and is grounded;

the gate terminal of the second N-type MOS transistor (MN2) is applied with a bias voltage (Vbias) to conduct the second N-type MOS transistor (MN2), the third P-type MOS transistor (MP3) and the fourth P-type MOS transistor (MP 4);

the gate terminal of the first P-type MOS transistor (MP1) is applied with a reference voltage (V_REF) To turn on the first P-type MOS transistor (MP1), the reference voltage is raised (Vbuf1) by using the series resistors (R1, R2) and provided to the source terminal of the first P-type MOS transistor (MP1) as the output buffer voltage (i.e., Vbuf1, which is Vbuf1 used as the driving signal of the discharge switch driver 104).

With regard to the charge and discharge control device 10 of each of the above embodiments, preferably, referring to fig. 5, the voltage buffer further includes at least one slave circuit (B) that duplicates the voltage at the source terminal of the first P-type MOS transistor of the master circuit (a) as a driving signal (i.e., the driving voltage Vbuf) of another discharge switch driver.

In the charge and discharge control device 10 according to each of the above embodiments, the slave circuit (B) preferably includes a fifth P-type MOS transistor (MP5), a sixth P-type MOS transistor (MP6), a first N-type MOS transistor (MN1), and a second P-type MOS transistor (MP2), and the source terminal of the fifth P-type MOS transistor (MP5) and the source terminal of the sixth P-type MOS transistor (MP6) are connected to the output voltage (Vcp1) of the voltage transformation device 105;

the gate terminal of the fifth P-type MOS transistor (MP5) is connected with the gate terminal of the sixth P-type MOS transistor (MP 6);

the drain end of the first N-type MOS tube (MN1) is respectively connected with the drain end and the gate end of the fifth P-type MOS tube (MP 5);

the source end of the second P-type MOS tube (MP2) is connected with the drain end of the sixth P-type MOS tube (MP 6);

the source terminal of the first N-type MOS transistor (MN1) is connected with the drain terminal of the second P-type MOS transistor (MP2) and is grounded;

the gate terminal of the first N-type MOS transistor (MN1) is applied with a bias voltage (Vbias) to conduct the first N-type MOS transistor (MN1), the fifth P-type MOS transistor (MP5) and the sixth P-type MOS transistor (MP 6);

the gate terminal of the second P-type MOS transistor (MP2) is applied with a reference voltage (V)_REF) The voltage of the source terminal of the second P-type MOS transistor (MP2) is used as the output buffer voltage (i.e. Vbuf) by turning on the second P-type MOS transistor (MP 2).

In the charge/discharge control device 10 according to each of the above embodiments, it is preferable that the first P-type MOS transistor (MP1) and the second P-type MOS transistor (MP2) are the same MOS transistor (the channel width/length ratio and other parameters are the same);

the first N-type MOS transistor (MN1) and the second N-type MOS transistor (MN2) are the same MOS transistor (the channel width-length ratio and other parameters are the same).

As shown in fig. 5, the voltage buffer of this embodiment includes a master circuit (a) and a slave circuit (B), and preferably, the MP3, MP4, MP5, and MP6 are all the same MOS transistors (the channel width-length ratio, etc. are the same).

As can be seen from the circuit configuration in FIG. 5, I_B1And I_B2Are equal.

As can be seen from the circuit configuration shown in fig. 5, the magnitude of Vbuf1 can be adjusted by controlling the magnitude of the reference voltage VREF and/or adjusting the proportional relationship of the series resistances (two R1), so that the voltage buffer outputs an appropriate buffer voltage as a driving signal (driving voltage) of the discharge switch driver 104.

With the charge and discharge control device 10 of each of the above embodiments, preferably, referring to fig. 7, the discharge switch driver 104 includes a driver switching device, and when the driver switching device is turned on, the discharge switch driver 104 applies a buffer voltage to the discharge switch to turn on the discharge switch.

Preferably, the discharge switch driver 104 of the charge and discharge control device 10 includes a first drive control logic device that controls the on and off of the driver switch device.

Fig. 7 illustrates an exemplary circuit structure of the discharge switch driver 104 according to an embodiment of the disclosure, and those skilled in the art can make appropriate adjustments to the circuit structure of the discharge switch driver 104 based on a full understanding of the technical solutions of the disclosure, which all fall within the protection scope of the disclosure.

Illustratively, the driver switch device in fig. 7 includes a P-type MOS transistor and an N-type MOS transistor, the gate terminals of the two MOS transistors are connected and commonly receive the driving signal (driving voltage) for driving the control logic device, and the drain terminals of the two MOS transistors are connected and the drain terminal voltage is used as the driving voltage of the discharge switch 102 (DSG).

The first driving control logic device may be a control circuit, a control chip or a part of a control chip, which controls the on or off of the driver switch device based on a preset driving control logic (e.g., a clock timing), and the present disclosure is not intended to limit the specific structure of the first driving control logic device, and may adopt a control circuit or a control chip solidified with a preset driving control logic in the prior art.

With the charge-discharge control device 10 of each of the above embodiments, it is preferable that the charge switch driver 103 includes the first current mirror 1031, the second current mirror 1032, and the current source (supplying the driving current Idrv) that supplies the driving current (Idrv), the first current mirror 1031 mirrors the driving current for the first time, and the second current mirror 1032 mirrors the driving current mirrored for the first time again to supply to the bias resistance (Rb) so that the voltage across the bias resistance (Rb) becomes the gate-source control voltage (Vgs, i.e., the driving signal) of the charge switch 101.

In consideration of the fact that the source terminal of the charge switch 101 is connected to the cathode voltage of the battery pack (unstable), the technical scheme of the present disclosure does not adopt a manner of directly applying a voltage to the gate terminal of the charge switch 101 as the turn-on voltage (Vgs) of the charge switch 101, but provides a stable driving current through a current source, and after being mirrored through a two-stage current mirror, generates the turn-on voltage (Vgs) which is stably unaffected by the cathode voltage fluctuation of the battery pack through a bias resistor (Rb), thereby improving the reliability of the charge switch 101.

Fig. 6 illustrates a circuit structure of the charging switch driver 103 according to a preferred embodiment of the present disclosure, and those skilled in the art can make appropriate adjustments to the circuit structure of the charging switch driver 103 based on a full understanding of the technical solutions of the present disclosure, all of which fall within the protection scope of the present disclosure.

With the charge and discharge control device 10 of the above embodiment, preferably, referring to fig. 6, the charge switch driver 103 further includes a second drive control logic device that controls the current source so that the current source outputs or does not output a drive current.

The second driving control logic device may be a control circuit, a control chip or a part of a control chip, and controls the current source to output the driving current or not to output the driving current based on a preset driving control logic (e.g., a clock timing).

In the charge/discharge control device 10 according to each of the above embodiments, a protection diode is preferably provided between the gate and the source of the charge switch 101.

With the charge-discharge control device 10 of each of the above embodiments, it is preferable to further include a current detection resistor (Rsns) to detect a charge current during charging of the battery and a discharge current during discharging of the battery, with reference to fig. 1.

Fig. 1 exemplarily shows a current detection resistor Rsns, and a voltage across the current detection resistor Rsns may be acquired by an ADC sampler or COMP (comparator), so as to obtain values of a discharge current and a charge current.

Preferably, the current sensing resistor Rsns is a precision resistor, and the resistance value thereof is not affected by temperature and the like.

In the charge/discharge control device 10 according to each of the above embodiments, the charge/discharge control device 10 is preferably in the form of a semiconductor chip.

According to still another aspect of the present disclosure, there is provided a semiconductor chip on which the charge and discharge control device 10 according to any one of the above embodiments is formed.

According to still another aspect of the present disclosure, there is provided a battery management system including: in the charge/discharge control device 10 according to any of the above embodiments, the charge/discharge control device 10 controls the charge/discharge of the battery device 20.

According to still another aspect of the present disclosure, there is provided an electric device including: a battery device; and the above-described battery management system that controls at least charging/discharging of the battery device 20. Referring to fig. 8, the electric device may be an electric car, a mobile phone, or the like.

In the description herein, reference to the description of the terms "one embodiment/mode," "some embodiments/modes," "example," "specific example" or "some examples" or the like means that a particular feature, structure, material, or characteristic described in connection with the embodiment/mode or example is included in at least one embodiment/mode or example of the present disclosure. In this specification, the schematic representations of the terms used above are not necessarily intended to be the same embodiment/mode or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments/modes or examples. Furthermore, the various embodiments/aspects or examples and features of the various embodiments/aspects or examples described in this specification can be combined and combined by one skilled in the art without conflicting therewith.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present disclosure, "a plurality" means at least two, e.g., two, three, etc., unless explicitly specifically limited otherwise.

It will be understood by those skilled in the art that the foregoing embodiments are merely for clarity of illustration of the disclosure and are not intended to limit the scope of the disclosure. Other variations or modifications may occur to those skilled in the art, based on the foregoing disclosure, and are still within the scope of the present disclosure.

Claims

1. A charge and discharge control device, comprising:

a discharge switch driver, the discharge switch being driven to conduct based on a driving signal of the discharge switch driver; and

2. The charge and discharge control device according to claim 1, wherein the charge switch and the discharge switch are both field effect transistors.

3. The charge and discharge control device according to claim 2, wherein the voltage transforming device includes a charge pump and a voltage buffer, the charge pump transforms a terminal voltage of the battery device to the first voltage, the first voltage is a supply voltage of the voltage buffer, and the voltage buffer outputs the second voltage.

4. The charge and discharge control device according to claim 3, wherein the charge pump includes a first switch, a second switch, a third switch, a first capacitor, and a second capacitor, the first switch is provided between a first end of the first capacitor and a positive terminal of the battery device, the second switch is provided between a second end of the first capacitor and a negative terminal of the battery device, the third switch is provided between the second end of the first capacitor and the positive terminal of the battery device, and the second capacitor is provided between the positive terminal of the battery device and the negative terminal or a ground terminal of the battery device.

5. The charge and discharge control device according to claim 3, wherein the voltage buffer includes an active circuit;

6. The charge and discharge control device according to claim 5, wherein the voltage buffer further comprises at least one slave circuit, the slave circuit copies a voltage of a source terminal of the first P-type MOS transistor of the master circuit as a driving signal of another discharge switch driver;

preferably, the driven circuit comprises a fifth P-type MOS transistor, a sixth P-type MOS transistor, a first N-type MOS transistor, and a second P-type MOS transistor, and a source terminal of the fifth P-type MOS transistor and a source terminal of the sixth P-type MOS transistor are connected to the output voltage of the voltage transformation device;

the grid end of the second P-type MOS tube is applied with the reference voltage to conduct the second P-type MOS tube, and the voltage of the source end of the second P-type MOS tube is used as the output buffer voltage;

preferably, the first P-type MOS transistor and the second P-type MOS transistor are the same MOS transistor; the first N-type MOS tube and the second N-type MOS tube are the same MOS tube;

preferably, the discharge switch driver includes a driver switching device, and when the driver switching device is turned on, the discharge switch driver applies the buffer voltage to the discharge switch to turn on the discharge switch;

preferably, the discharge switch driver comprises a first drive control logic device which controls the on and off of the driver switch device;

preferably, the charge switch driver includes a first current mirror, a second current mirror and a current source, the current source provides a driving current, the first current mirror mirrors the driving current for the first time, the second current mirror mirrors the driving current mirrored for the first time again to provide the driving current to the bias resistor, so that the voltage across the bias resistor serves as the gate-source control voltage of the charge switch;

preferably, the charge switch driver further comprises a second drive control logic device that controls the current source such that the current source outputs or does not output the drive current;

preferably, a protection diode is arranged between the grid electrode and the source electrode of the charging switch;

preferably, a current detection resistor is further included to detect a charging current of the battery during charging and a discharging current of the battery during discharging.

7. The charge and discharge control device according to claim 1, wherein the charge and discharge control device is in the form of a semiconductor chip.

8. A semiconductor chip, characterized in that the charge-discharge control device according to any one of claims 1 to 7 is formed.

9. A battery management system, comprising:

the charge and discharge control device according to any one of claims 1 to 7, which performs charge/discharge control of a battery device.

10. An electrical device, comprising:

a battery device; and

the battery management system of claim 9, the battery management system controlling at least charging/discharging of the battery device.