Charging and discharging control devices, semiconductor chips, battery management systems and electrical equipment

Abstract

The present disclosure provides a charge and discharge control device, including: a charging switch, when the battery device is charged, the charging switch is driven to turn on; a charging switch driver, the charging switch is driven to turn on based on a driving signal of the charging switch driver; a discharging switch, when the battery device is discharged, the discharging switch is driven to turn on; a discharging switch driver, the discharging switch is driven to turn on based on a driving signal of the discharging switch driver; and a transformer, which transforms the terminal voltage of the battery device to generate at least a first voltage and a second voltage, the second voltage is less than the first voltage, 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. The present disclosure also provides a semiconductor chip, a battery management system, and an electric device.

Description

Technical Field

[0001] The present disclosure relates to the field of battery technology, and in particular to a charge and discharge control device, a semiconductor chip, a battery management system and an electrical device. Background Art

[0002] In the prior art, a large number of electrical devices (electric vehicles, mobile phones, etc.) use battery packs (or battery cells, battery packs) to provide electrical energy. The discharge of the battery pack provides electrical energy for the load, and the battery pack also needs to be charged.

[0003] During the charging and discharging process of the battery pack, the charging circuit and the discharging circuit need to be controlled. In the prior art, field effect transistors are often used as control devices for the charging circuit and the discharging circuit (to turn on or off the charging circuit, and to turn on or off the discharging circuit).

[0004] However, since the source of the field effect transistor used as a discharge circuit is generally connected to the negative voltage of the battery pack / battery cell (stable), and the source of the field effect transistor used as a charging circuit is generally connected to the negative voltage of the battery pack (unstable), the driving circuit of the field effect transistor Vgs used as a discharge circuit and the field effect transistor Vgs used as a charging circuit in the prior art may cause failure of the field effect transistor used as a charging circuit. Summary of the invention

[0005] In order to solve at least one of the above technical problems, the present disclosure provides a new charge and discharge control device, a semiconductor chip, a battery management system and an electric device.

[0006] The charge and discharge control device, semiconductor chip, battery management system and electrical equipment disclosed in the present invention are implemented through the following technical solutions.

[0007] According to one aspect of the present disclosure, there is provided a charge and discharge control device, comprising:

[0008] A charging switch, when the battery device is charged, the charging switch is driven to conduct;

[0009] a charging switch driver, wherein the charging switch is driven to be turned on based on a driving signal of the charging switch driver;

[0010] A discharge switch, when the battery device is discharged, the discharge switch is driven to conduct;

[0011] a discharge switch driver, wherein the discharge switch is driven to be turned on based on a drive signal of the discharge switch driver; and

[0012] A transformer device, wherein the transformer device transforms the terminal voltage of the battery device to generate at least a first voltage and a second voltage, wherein the second voltage is less than the first voltage, 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.

[0013] 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.

[0014] 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 the terminal voltage of the battery device to the first voltage, the first voltage serves as the power supply voltage of the voltage buffer, and the voltage buffer outputs the second voltage.

[0015] 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 arranged between the first end of the first capacitor and the positive terminal of the battery device, the second switch is arranged between the second end of the first capacitor and the negative terminal of the battery device, the third switch is arranged between the second end of the first capacitor and the positive terminal of the battery device, and the second capacitor is arranged between the positive terminal of the battery device and the negative terminal or the ground terminal of the battery device.

[0016] According to the charge and discharge control device of at least one embodiment of the present disclosure, the voltage buffer includes an active circuit;

[0017] The active circuit comprises a third P-type MOS transistor, a fourth P-type MOS transistor, a second N-type MOS transistor, and a first P-type MOS transistor, and a source terminal of the third P-type MOS transistor and a source terminal of the fourth P-type MOS transistor are connected to the output voltage of the voltage conversion device;

[0018] The gate terminal of the third P-type MOS transistor is connected to the gate terminal of the fourth P-type MOS transistor;

[0019] The drain terminal of the second N-type MOS transistor is respectively connected to the drain terminal and the gate terminal of the third P-type MOS transistor;

[0020] The source terminal of the first P-type MOS transistor is connected to the drain terminal of the fourth P-type MOS transistor;

[0021] The source terminal of the second N-type MOS transistor is connected to the drain terminal of the first P-type MOS transistor and is grounded;

[0022] A bias voltage is applied to the gate terminal of the second N-type MOS transistor to turn on the second N-type MOS transistor, the third P-type MOS transistor and the fourth P-type MOS transistor;

[0023] A reference voltage is applied to the gate terminal of the first P-type MOS transistor to turn on the first P-type MOS transistor, and a series resistor is used to raise the reference voltage and provide it to the source terminal of the first P-type MOS transistor as an output buffer voltage.

[0024] According to the charge and discharge control device of at least one embodiment of the present disclosure, the voltage buffer also includes at least one slave circuit, which copies the voltage at the source terminal of the first P-type MOS tube of the active circuit as a driving signal for another discharge switch driver.

[0025] 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 the source terminal of the fifth P-type MOS transistor and the source terminal of the sixth P-type MOS transistor are connected to the output voltage of the transformer;

[0026] The gate terminal of the fifth P-type MOS transistor is connected to the gate terminal of the sixth P-type MOS transistor;

[0027] The drain terminal of the first N-type MOS transistor is respectively connected to the drain terminal and the gate terminal of the fifth P-type MOS transistor;

[0028] The source terminal of the second P-type MOS transistor is connected to the drain terminal of the sixth P-type MOS transistor;

[0029] The source terminal of the first N-type MOS transistor is connected to the drain terminal of the second P-type MOS transistor and is grounded;

[0030] The bias voltage is applied to the gate terminal of the first N-type MOS transistor to turn on the first N-type MOS transistor, the fifth P-type MOS transistor and the sixth P-type MOS transistor;

[0031] The reference voltage is applied to the gate terminal of the second P-type MOS transistor to turn on the second P-type MOS transistor, and the voltage at the source terminal of the second P-type MOS transistor is used as the output buffer voltage.

[0032] According to the charge and discharge control device of at least one embodiment of the present disclosure, the first P-type MOS tube and the second P-type MOS tube are the same MOS tube; the first N-type MOS tube and the second N-type MOS tube are the same MOS tube.

[0033] According to the charge and discharge control device of at least one embodiment of the present disclosure, the discharge switch driver includes a driver switch device, and when the driver switch device is turned on, the discharge switch driver applies the buffer voltage to the discharge switch to turn on the discharge switch.

[0034] 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, and the first drive control logic device controls the conduction and disconnection of the driver switch device.

[0035] According to the charge and discharge control device of at least one embodiment of the present disclosure, the charging 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 performs a first mirroring of the driving current, and the second current mirror performs a second mirroring of the driving current after the first mirroring to provide it to a bias resistor, so that the voltage across the bias resistor serves as the gate-source control voltage of the charging switch.

[0036] According to the charge and discharge control device of at least one embodiment of the present disclosure, the charging switch driver further includes a second drive control logic device, which controls the current source so that the current source outputs or does not output the drive current.

[0037] 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 charging switch.

[0038] According to at least one embodiment of the present disclosure, the charge and discharge control device further includes a current sensing resistor to detect the charging current of the battery during the charging process and the discharging current of the battery during the discharging process.

[0039] According to at least one embodiment of the present disclosure, the charge and discharge control device is in the form of a semiconductor chip.

[0040] According to another aspect of the present disclosure, a semiconductor chip is provided, on which the charge and discharge control device described above is formed.

[0041] According to another aspect of the present disclosure, there is provided a battery management system, comprising:

[0042] Any of the above-mentioned charge and discharge control devices, wherein the charge and discharge control device controls the charge and discharge of the battery device.

[0043] According to another aspect of the present disclosure, there is provided an electric device, comprising:

[0044] battery device; and,

[0045] The battery management system mentioned above at least controls the charging / discharging of the battery device. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The accompanying drawings illustrate exemplary embodiments of the present disclosure and together with the description serve to explain the principles of the present disclosure. These drawings are included to provide a further understanding of the present disclosure and are incorporated in and constitute a part of this specification.

[0047] Figure 1 It is a schematic diagram of the circuit structure of a charge and discharge control device according to one embodiment of the present disclosure.

[0048] Figure 2 Schematic diagram of the circuit structure of a charge pump of a charge and discharge control device according to an embodiment of the present disclosure.

[0049] Figure 3 and Figure 4 They are Figure 2 A schematic diagram showing a first working state and a second working state of a charge pump is shown.

[0050] Figure 5 Schematic diagram of the circuit structure of a transformer device of a charge and discharge control device according to an embodiment of the present disclosure.

[0051] Figure 6 Schematic diagram of the circuit structure of a charging switch driver of a charging and discharging control device according to an embodiment of the present disclosure.

[0052] Figure 7 Schematic diagram of the circuit structure of a discharge switch driver of a charge and discharge control device according to an embodiment of the present disclosure.

[0053] Figure 8 It is a schematic block diagram of the structure of an electric device according to an embodiment of the present disclosure.

[0054] Description of Reference Numerals

[0055] 10. Charge and discharge control device

[0056] 20 Battery Device

[0057] 101 Charging switch

[0058] 102 Discharge switch

[0059] 103 Charging switch driver

[0060] 104 Discharge switch driver

[0061] 105 Transformer

[0062] 201 Battery Cell

[0063] 1031 First Current Mirror

[0064] 1032 Second current mirror. DETAILED DESCRIPTION

[0065] The present disclosure is further described in detail below in conjunction with the accompanying drawings and implementations. It is understood that the specific implementations described herein are only used to explain the relevant content, rather than to limit the present disclosure. It should also be noted that, for ease of description, only the parts related to the present disclosure are shown in the accompanying drawings.

[0066] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in the present disclosure can be combined with each other. The technical solution of the present disclosure will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0067] Unless otherwise specified, the exemplary embodiments / embodiments shown will be understood as providing exemplary features of various details of some ways in which the technical concept of the present disclosure can be implemented in practice. Therefore, unless otherwise specified, the features of the various embodiments / embodiments can be combined, separated, interchanged and / or rearranged without departing from the technical concept of the present disclosure.

[0068] The use of cross-hatching and / or shading in the accompanying drawings is generally used to make the boundaries between adjacent components clear. As such, unless otherwise specified, the presence or absence of cross-hatching or shading does not convey or indicate any preference or requirement for the specific materials, material properties, dimensions, proportions, commonalities between the components shown, and / or any other characteristics, attributes, properties, etc. of the components. In addition, in the accompanying drawings, the sizes and relative sizes of the components may be exaggerated for clarity and / or descriptive purposes. When the exemplary embodiments can be implemented differently, the specific process sequence can be performed in a different order than described. For example, two successively described processes can be performed substantially simultaneously or in an order opposite to the described order. In addition, the same figure numbers represent the same components.

[0069] When a component is referred to as being "on" or "over," "connected to," or "coupled to" another component, the component may be directly on, directly connected to, or directly coupled to the other component, or intervening components may be present. However, when a component is referred to as being "directly on," "directly connected to," or "directly coupled to" another component, there are no intervening components. For this purpose, the term "connected" may refer to a physical connection, an electrical connection, etc., with or without intervening components.

[0070] For descriptive purposes, the present disclosure may use spatially relative terms such as "under," "beneath," "under," "down," "over," "upper," "above," "higher," and "side (e.g., in a "sidewall")," to describe the relationship of one component to another (other) component as shown in the accompanying drawings. The 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 accompanying drawings. For example, if the device in the accompanying drawings is turned over, components described as "under" or "beneath" other components or features would subsequently be positioned "over" the other components or features. Thus, the exemplary term "under" can encompass both the "above" and "below" orientations. Furthermore, the device may be otherwise oriented (e.g., rotated 90 degrees or at other orientations), and the spatially relative descriptors used herein should be interpreted accordingly.

[0071] The terms used here are for the purpose of describing specific embodiments, and are not intended to be restrictive. As used here, unless the context clearly indicates otherwise, the singular forms "one (kind, person)" and "said (the)" are also intended to include plural forms. In addition, when the terms "comprise" and / or "include" and their variations are used in this specification, it is explained that there are stated features, integral bodies, steps, operations, parts, assemblies and / or their groups, but it is not excluded that there are or add one or more other features, integral bodies, steps, operations, parts, assemblies and / or their groups. It should also be noted that, as used here, the terms "substantially", "approximately" and other similar terms are used as approximate terms and not as degree terms, so that they are used to explain the inherent deviations of the measured values, calculated values ​​and / or the values ​​provided that will be recognized by those of ordinary skill in the art.

[0072] Combined with the following Figures 1 to 8 The charge and discharge control device, semiconductor chip, battery management system and electrical equipment disclosed in the present invention are described in detail.

[0073] Figure 1 It is a circuit configuration diagram of a charge and discharge control device according to one embodiment of the present disclosure.

[0074] Figure 1 The battery device 20 shown in the figure includes a battery cell 201. 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 cells 201 connected in series. The battery cell 201 may be a lithium battery or other types of batteries.

[0075] According to one embodiment of the present disclosure, referring to Figure 1 , the charge and discharge control device 10 comprises:

[0076] A charging switch 101, when the battery device 20 is charged, the charging switch 101 is driven to be turned on;

[0077] A charging switch driver 103, wherein the charging switch 101 is driven to be turned on based on a driving signal of the charging switch driver 103;

[0078] The discharge switch 102 is driven to be turned on when the battery device 20 is discharging;

[0079] a discharge switch driver 104, wherein the discharge switch 102 is driven to be turned on based on a driving signal of the discharge switch driver 104; and

[0080] The transformer 105 transforms the terminal voltage of the battery device 20 to generate at least a first voltage and a second voltage, wherein the second voltage is less than the first voltage. The charging switch driver 103 generates a driving signal based on the first voltage, and the discharging switch driver 104 generates a driving signal based on the second voltage.

[0081] The voltage transformation device 105 of the present disclosure can output a corresponding first voltage ( Vcp1 ) and a second voltage ( Vbuf ) based on the terminal voltage of the battery device 20 to meet the requirements of the charging switch driver 103 and the discharging switch driver 104 .

[0082] In the charge and discharge control device 10 of the above embodiment, both the charge switch 101 and the discharge switch 102 are field effect transistors.

[0083] Figure 1 The structure of the field effect transistors of the charging switch 101 and the discharging switch 102 is exemplarily shown in the figure. Those skilled in the art can adjust the structure (channel type, etc.) of the charging switch 101 and the discharging switch 102 based on the technical solution disclosed in the present invention.

[0084] For the charge and discharge control device 10 of each of the above-mentioned embodiments, preferably, the transformer 105 includes a charge pump (CP1) and a voltage buffer, the charge pump (CP1) converts the terminal voltage of the battery device 20 to a first voltage (Vcp1), the first voltage (Vcp1) serves as a power supply voltage (Vcp1) of the voltage buffer, and the voltage buffer outputs a second voltage (Vbuf).

[0085] For the charge and discharge control device 10 in each of the above embodiments, preferably, the charge pump (CP1) includes a first switch (SW1), a second switch (SW2), a third switch (SW3), a first capacitor (C FLY1 ) and the second capacitor (C B1 ), the first switch (SW1) is set at the first capacitor (C FLY1) and the positive terminal of the battery device 20, the second switch (SW2) is arranged between the first capacitor (C FLY1 ) and the negative terminal of the battery device 20, the third switch (SW3) is set between the first capacitor (C FLY1 ) and the positive terminal of the battery device 20, the second capacitor (C B1 ) is arranged between the positive terminal of the battery device 20 and the negative terminal or the ground terminal of the battery device 20.

[0086] Figure 2 The circuit structure of a charge pump of an embodiment of the present disclosure is shown, and the charge pump increases the terminal voltage of the battery device 20 to twice the terminal voltage, that is, Vcp1=2×Vbat+. Those skilled in the art should understand that when the battery device 20 is a battery pack composed of multiple battery cells 201 connected in series, the charge pump can adopt a charge pump or transformer with a step-down function in the prior art to convert the terminal voltage of the battery device 20 to the required first voltage.

[0087] Figure 3 to Figure 4 The working principle of the charge pump of one embodiment of the present disclosure is shown as follows: Figure 3 As shown, in the first half of the working cycle, when the first switch (SW1) and the second switch (SW2) are closed and the third switch (SW3) is open, the first capacitor (C FLY1 ) accumulates charge, the first capacitor (C FLY1 ) rises to Vbat+; in the second half of the working cycle, Figure 4 As shown, the first switch (SW1) and the second switch (SW2) are disconnected, the third switch (SW3) is closed, and the first capacitor (C FLY1 )’s first end voltage rises to 2×Vbat+.

[0088] For the charge and discharge control device 10 of each of the above-mentioned embodiments, preferably, the voltage buffer includes an active circuit (A).

[0089] refer to Figure 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), and 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 transformer 105;

[0090] The gate terminal of the third P-type MOS transistor (MP3) is connected to the gate terminal of the fourth P-type MOS transistor (MP4);

[0091] The drain terminal of the second N-type MOS transistor (MN2) is respectively connected to the drain terminal and the gate terminal of the third P-type MOS transistor (MP3);

[0092] The source terminal of the first P-type MOS transistor (MP1) is connected to the drain terminal of the fourth P-type MOS transistor (MP4);

[0093] A source terminal of the second N-type MOS transistor (MN2) is connected to a drain terminal of the first P-type MOS transistor (MP1) and is grounded;

[0094] A bias voltage (Vbias) is applied to the gate terminal of the second N-type MOS transistor (MN2) to turn on the second N-type MOS transistor (MN2), the third P-type MOS transistor (MP3) and the fourth P-type MOS transistor (MP4);

[0095] A reference voltage (V REF ) is used to turn on the first P-type MOS tube (MP1), and the reference voltage is raised (Vbuf1) using the series resistors (R1, R2) and provided to the source terminal of the first P-type MOS tube (MP1) to serve as an output buffer voltage (i.e., Vbuf1, which can be used as a driving signal of the discharge switch driver 104).

[0096] For the charge and discharge control device 10 in each of the above embodiments, preferably, refer to Figure 5 The voltage buffer also includes at least one slave circuit (B), which replicates the voltage at the source terminal of the first P-type MOS tube of the active circuit (A) to serve as a driving signal (i.e., driving voltage Vbuf) for another discharge switch driver.

[0097] For the charge and discharge control device 10 of each of the above embodiments, preferably, the slave circuit (B) 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 transformer 105;

[0098] The gate terminal of the fifth P-type MOS transistor (MP5) is connected to the gate terminal of the sixth P-type MOS transistor (MP6);

[0099] The drain terminal of the first N-type MOS transistor (MN1) is respectively connected to the drain terminal and the gate terminal of the fifth P-type MOS transistor (MP5);

[0100] The source terminal of the second P-type MOS transistor (MP2) is connected to the drain terminal of the sixth P-type MOS transistor (MP6);

[0101] A source terminal of the first N-type MOS transistor (MN1) is connected to a drain terminal of the second P-type MOS transistor (MP2) and is grounded;

[0102] A bias voltage (Vbias) is applied to the gate terminal of the first N-type MOS transistor (MN1) to turn on the first N-type MOS transistor (MN1), the fifth P-type MOS transistor (MP5) and the sixth P-type MOS transistor (MP6);

[0103] The reference voltage (V REF ) is used to turn on the second P-type MOS transistor (MP2), and the voltage at the source terminal of the second P-type MOS transistor (MP2) is used as the output buffer voltage (ie, Vbuf).

[0104] For the charge and discharge control device 10 of each of the above embodiments, preferably, the first P-type MOS transistor (MP1) and the second P-type MOS transistor (MP2) are the same MOS transistors (parameters such as channel width-to-length ratio are the same);

[0105] The first N-type MOS transistor (MN1) and the second N-type MOS transistor (MN2) are the same MOS transistors (parameters such as channel width-to-length ratio are the same).

[0106] like Figure 5 As shown, the voltage buffer of this embodiment includes an active circuit (A) and a passive circuit (B). Preferably, MP3, MP4, MP5, and MP6 are all the same MOS tubes (with the same parameters such as channel width-to-length ratio).

[0107] Depend on Figure 5 From the circuit structure in, we can see that I B1 with I B2 equal.

[0108] Depend on Figure 5 As can be seen from the circuit structure shown, the size of Vbuf1 can be adjusted by controlling the size of the reference voltage VREF and / or adjusting the proportional relationship of the series resistors (two R1), so that the voltage buffer outputs a suitable buffer voltage as the drive signal (drive voltage) of the discharge switch driver 104.

[0109] For the charge and discharge control device 10 in each of the above embodiments, preferably, refer to Figure 7 The discharge switch driver 104 includes a driver switch device. When the driver switch device is turned on, the discharge switch driver 104 applies a buffer voltage to the discharge switch to turn on the discharge switch.

[0110] Preferably, the discharge switch driver 104 of the charge and discharge control device 10 comprises a first drive control logic device, and the first drive control logic device controls the on and off of the driver switch device.

[0111] Figure 7 The circuit structure of the discharge switch driver 104 of an embodiment of the present disclosure is exemplarily shown. Based on a full understanding of the technical solution of the present disclosure, those skilled in the art can make appropriate adjustments to the circuit structure of the discharge switch driver 104, all of which fall within the protection scope of the present disclosure.

[0112] For example, Figure 7 The driver switch device includes a P-type MOS tube and an N-type MOS tube, the gate terminals of the two MOS tubes are connected and jointly receive the driving signal (driving voltage) of the driving control logic device, the drain terminals of the two MOS tubes are connected and the drain terminal voltage is used as the driving voltage of the discharge switch 102 (DSG).

[0113] Among them, the first drive control logic device can be a control circuit, a control chip or a part of a control chip, which controls the conduction or disconnection of the driver switching device based on a preset drive control logic (such as clock timing). The present disclosure does not intend to specifically limit the specific structure of the first drive control logic device, and it can adopt a control circuit or control chip with a preset drive control logic in the prior art.

[0114] For the charge and discharge control device 10 of each of the above-mentioned embodiments, preferably, the charging switch driver 103 includes a first current mirror 1031, a second current mirror 1032 and a current source (providing a driving current Idrv), the current source provides a 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 after the first mirroring again to provide it to the bias resistor (Rb), so that the voltage across the bias resistor (Rb) serves as the gate-source control voltage (Vgs, i.e., the driving signal) of the charging switch 101.

[0115] Taking into account that the source terminal of the charging switch 101 is connected to the negative voltage of the battery pack (unstable), the technical solution disclosed in the present invention does not adopt the method of directly applying a voltage to the gate terminal of the charging switch 101 as the turn-on voltage (Vgs) of the charging switch 101, but provides a stable driving current through a current source. After being mirrored by two-stage current mirrors, a stable turn-on voltage (Vgs) that is not affected by the negative voltage fluctuation of the battery pack is generated through a bias resistor (Rb), thereby improving the reliability of the charging switch 101.

[0116] Figure 6 The circuit structure of the charging switch driver 103 of a preferred embodiment of the present disclosure is exemplarily shown. 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 solution of the present disclosure, all of which fall within the protection scope of the present disclosure.

[0117] For the charge and discharge control device 10 of the above embodiment, preferably, reference is made to Figure 6 The charging switch driver 103 further includes a second driving control logic device, which controls the current source so that the current source outputs or does not output the driving current.

[0118] Among them, the second drive control logic device can be a control circuit, a control chip or a part of a control chip, which controls the current source to output a drive current or not output a drive current based on a preset drive control logic (such as a clock timing). The present disclosure does not intend to specifically limit the specific structure of the second drive control logic device, and it can adopt a control circuit or control chip with a preset drive control logic in the prior art.

[0119] For the charge and discharge control device 10 of each of the above embodiments, preferably, a protection diode is provided between the gate and the source of the charging switch 101 .

[0120] For the charge and discharge control device 10 in each of the above embodiments, preferably, refer to Figure 1 , and also includes a current sensing resistor (Rsns) to detect the charging current of the battery during the charging process and the discharging current of the battery during the discharging process.

[0121] Figure 1 The current sensing resistor Rsns is exemplarily shown in FIG. 1 . The voltage across the current sensing resistor Rsns can be collected by an ADC sampler or a COMP (comparator) to obtain the values ​​of the discharge current and the charge current.

[0122] Preferably, the current-sense resistor Rsns is a precision resistor, and its resistance value is not affected by factors such as temperature.

[0123] For the charge and discharge control device 10 of each of the above-mentioned embodiments, preferably, the charge and discharge control device 10 is in the form of a semiconductor chip.

[0124] According to another aspect of the present disclosure, a semiconductor chip is provided, on which the charge and discharge control device 10 according to any one of the above-mentioned embodiments is formed.

[0125] According to another aspect of the present disclosure, a battery management system is provided, including: the charge and discharge control device 10 of any one of the above embodiments, the charge and discharge control device 10 controls the charge and discharge of the battery device 20 .

[0126] According to another aspect of the present disclosure, there is provided an electric device, comprising: a battery device; and the above-mentioned battery management system, wherein the battery management system at least controls the charging / discharging of the battery device 20. Figure 8, where the electrical equipment can be electric vehicles, mobile phones, etc.

[0127] In the description of this specification, the description with reference to the terms "one embodiment / method", "some embodiments / methods", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment / method or example are included in at least one embodiment / method or example of the present disclosure. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment / method or example. Moreover, the specific features, structures, materials or characteristics described may be combined in a suitable manner in any one or more embodiments / methods or examples. In addition, those skilled in the art may combine and combine the different embodiments / methods or examples described in this specification and the features of the different embodiments / methods or examples, unless they are contradictory.

[0128] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present disclosure, "plurality" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0129] Those skilled in the art should understand that the above embodiments are only for the purpose of clearly illustrating the present disclosure, and are not intended to limit the scope of the present disclosure. For those skilled in the art, other changes or modifications may be made based on the above disclosure, and these changes or modifications are still within the scope of the present disclosure.

Claims

1. A charge and discharge control device, characterized in that: include: A charging switch, when the battery device is charged, the charging switch is driven to conduct; a charging switch driver, wherein the charging switch is driven to be turned on based on a driving signal of the charging switch driver; A discharge switch, when the battery device is discharging, the discharge switch is driven to be turned on, and both the charging switch and the discharge switch are field effect transistors; a discharge switch driver, wherein the discharge switch is driven to be turned on based on a drive signal of the discharge switch driver; as well as a voltage transformation device, wherein the voltage transformation device transforms the terminal voltage of the battery device to generate at least a first voltage and a second voltage, wherein the second voltage is less than the first voltage, 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; The current sensing resistor detects the charging current of the battery during charging and the discharging current of the battery during discharging. The voltage conversion device includes a charge pump and a voltage buffer. The charge pump converts the terminal voltage of the battery device to the first voltage. The first voltage is used as a power supply voltage of the voltage buffer. The voltage buffer outputs the second voltage. Wherein, the voltage buffer comprises an active circuit; The active circuit includes 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 a source terminal of the third P-type MOS tube and a source terminal of the fourth P-type MOS tube are connected to the output voltage of the voltage transformation device; a gate terminal of the third P-type MOS tube is connected to a gate terminal of the fourth P-type MOS tube; a drain terminal of the second N-type MOS tube is respectively connected to a drain terminal and a gate terminal of the third P-type MOS tube; a source terminal of the first P-type MOS tube is connected to a drain terminal of the fourth P-type MOS tube; a source terminal of the second N-type MOS tube is connected to a drain terminal of the first P-type MOS tube and is grounded; a bias voltage is applied to a gate terminal of the second N-type MOS tube to turn on the second N-type MOS tube, the third P-type MOS tube and the fourth P-type MOS tube; a reference voltage is applied to a gate terminal of the first P-type MOS tube to turn on the first P-type MOS tube, and a series resistor is used to raise the reference voltage and provide it to a source terminal of the first P-type MOS tube as an output buffer voltage.

2. The charge and discharge control device according to claim 1, characterized in that: The charge pump includes a first switch, a second switch, a third switch, a first capacitor and a second capacitor. The first switch is arranged between the first end of the first capacitor and the positive terminal of the battery device, the second switch is arranged between the second end of the first capacitor and the negative terminal of the battery device, the third switch is arranged between the second end of the first capacitor and the positive terminal of the battery device, and the second capacitor is arranged between the positive terminal of the battery device and the negative terminal or the ground terminal of the battery device.

3. The charge and discharge control device according to claim 1, characterized in that: The voltage buffer further includes at least one slave circuit, which replicates the voltage at the source terminal of the first P-type MOS transistor of the active circuit to serve as a driving signal for another discharge switch driver.

4. The charge and discharge control device according to claim 3, characterized in that: The slave 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 conversion device; The gate terminal of the fifth P-type MOS transistor is connected to the gate terminal of the sixth P-type MOS transistor; The drain terminal of the first N-type MOS transistor is respectively connected to the drain terminal and the gate terminal of the fifth P-type MOS transistor; The source terminal of the second P-type MOS transistor is connected to the drain terminal of the sixth P-type MOS transistor; The source terminal of the first N-type MOS transistor is connected to the drain terminal of the second P-type MOS transistor and is grounded; The bias voltage is applied to the gate terminal of the first N-type MOS transistor to turn on the first N-type MOS transistor, the fifth P-type MOS transistor and the sixth P-type MOS transistor; The reference voltage is applied to the gate terminal of the second P-type MOS transistor to turn on the second P-type MOS transistor, and the voltage at the source terminal of the second P-type MOS transistor is used as the output buffer voltage.

5. The charge and discharge control device according to claim 4, characterized in that: The first P-type MOS transistor and the second P-type MOS transistor are the same MOS transistor; the first N-type MOS transistor and the second N-type MOS transistor are the same MOS transistor.

6. The charge and discharge control device according to claim 1, characterized in that: The discharge switch driver includes a driver switch device, and when the driver switch device is turned on, the discharge switch driver applies the buffer voltage to the discharge switch to turn on the discharge switch.

7. The charge and discharge control device according to claim 6, characterized in that: The discharge switch driver includes a first drive control logic device, which controls the conduction and disconnection of the driver switch device.

8. The charge and discharge control device according to claim 1, characterized in that: The charging 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 performs a first mirroring of the driving current, and the second current mirror performs a second mirroring of the driving current after the first mirroring to provide it to a bias resistor, so that the voltage across the bias resistor serves as a gate-source control voltage of the charging switch.

9. The charge and discharge control device according to claim 8, characterized in that: The charging switch driver further includes a second driving control logic device, which controls the current source so that the current source outputs or does not output the driving current.

10. The charge and discharge control device according to claim 1, characterized in that: A protection diode is arranged between the gate and the source of the charging switch.

11. The charge and discharge control device according to claim 1, characterized in that: The charge and discharge control device is in the form of a semiconductor chip.

12. A semiconductor chip, characterized in that: A charge and discharge control device according to any one of claims 1 to 11 is provided.

13. A battery management system, characterized in that: include: The charge and discharge control device according to any one of claims 1 to 11, wherein the charge and discharge control device controls the charge and discharge of a battery device.

14. An electrical device, characterized in that: include: Battery device; as well as The battery management system according to claim 13, wherein the battery management system at least controls the charging / discharging of the battery device.

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