A positive terminal protection drive control circuit for a lithium battery protection board

Abstract

The present invention discloses a positive terminal protection drive control circuit for a lithium battery protection board, comprising: a charge pump circuit, a positive terminal drive circuit of the protection board, and a charging voltage acquisition circuit; the charge pump circuit is connected to the positive terminal drive circuit of the protection board and the lithium battery; the positive terminal drive circuit of the protection board is connected to the charge pump circuit, the charging voltage acquisition circuit, and the lithium battery; the charging voltage acquisition circuit is connected to the charge pump circuit and the positive terminal drive circuit of the protection board. The present application can have high flexibility while providing a protection function, can modify corresponding components according to requirements without replacing the whole, the circuit supports soft start, has a small starting current, improves the service life of components while ensuring the stable product quality, and the DC bias voltage introduced in the circuit can optimize the static characteristics of transistors.

Description

Technical Field

[0001] The present invention relates to the field of circuit technologies, and particularly to a positive terminal protection drive control circuit for a lithium battery protection board. Background Art

[0002] The method adopted for the positive terminal of the existing lithium battery protection board is to use an integrated IC with specific protection functions. When overcharging, over-discharging, or over-current occurs in the lithium battery, the corresponding functions are turned off to achieve the protection purpose. However, the functions of this method are relatively fixed and it is difficult to make corresponding adjustments according to specific requirements. When there are new requirements, it often faces difficulties in changing the peripheral circuit or the inability to meet the requirements due to the limitations of the IC's own functions. This will result in the original protection board not being able to meet the new requirements, and even the entire solution may need to be completely redone. In addition, when a part of the circuit inside the integrated IC fails or is damaged, the entire IC needs to be replaced, which greatly increases the time and money costs during use.

[0003] Therefore, the existing technology needs to be improved. Summary of the Invention

[0004] The technical problem to be solved by the embodiments of the present invention is: to provide a positive terminal protection drive control circuit for a lithium battery protection board to solve the problems existing in the prior art.

[0005] According to one aspect of the embodiments of the present invention, a positive terminal protection drive control circuit for a lithium battery protection board is disclosed, including:

[0006] A charge pump circuit, a positive terminal drive circuit of the protection board, and a charging voltage acquisition circuit;

[0007] The charge pump circuit is connected to the positive terminal drive circuit of the protection board and the lithium battery, and the charge pump circuit is used to boost the voltage for the positive terminal drive circuit of the protection board;

[0008] The positive terminal drive circuit of the protection board is connected to the charge pump circuit, the charging voltage acquisition circuit, and the lithium battery, and is used to stop charging when the positive terminal drive circuit of the protection board receives a charging stop signal when the lithium battery is in an overcharged state, and stop discharging when the positive terminal drive circuit of the protection board receives a discharging stop signal when the lithium battery is in an over-discharged state;

[0009] The charging voltage acquisition circuit is connected to the charge pump circuit and the positive terminal drive circuit of the protection board, and is used to detect the charging voltage of the lithium battery.

[0010] In another embodiment, the positive terminal drive circuit of the protection board includes:

[0011] The first MOS transistor, the second MOS transistor, the third MOS transistor, the protection circuit, the fifth MOS transistor, the sixth MOS transistor, the seventh MOS transistor, the eighth MOS transistor, the ninth MOS transistor, the tenth MOS transistor, the first control signal port, the second control signal port, the third control signal port, the first power output terminal;

[0012] The first MOS transistor is connected to the second MOS transistor, the protection circuit, the fifth MOS transistor, the seventh MOS transistor, and the lithium battery;

[0013] The second MOS transistor is connected to the third MOS transistor and the seventh MOS transistor;

[0014] The third MOS transistor is connected to the ninth MOS transistor, the tenth MOS transistor, and the first power output terminal;

[0015] The fifth MOS transistor is connected to the sixth MOS transistor, the seventh MOS transistor, the tenth MOS transistor, and the charge pump circuit;

[0016] The seventh MOS transistor is connected to the eighth MOS transistor;

[0017] The sixth MOS transistor is connected to the eighth MOS transistor;

[0018] The sixth MOS transistor and the eighth MOS transistor are connected to the first control signal port;

[0019] The ninth MOS transistor is connected to the tenth MOS transistor and the third control signal port;

[0020] The protection circuit is connected to the second control signal port.

[0021] In another embodiment, the protection circuit includes: a fourth MOS transistor, a first resistor, a second resistor, and a third resistor;

[0022] The first resistor is connected to the drain of the fourth MOS transistor, the second resistor is connected to the gate of the fourth MOS transistor, and the third resistor is connected to the gate and source of the fourth MOS transistor;

[0023] The second resistor is connected to the second control signal port.

[0024] In another embodiment, the charging voltage acquisition circuit includes: a voltage stabilizing circuit, an eleventh MOS transistor, a twelfth MOS transistor, a fourth control signal port, and a fifth control signal port;

[0025] The voltage stabilizing circuit is connected to the charge pump circuit, the fourth control signal port, and the eleventh MOS transistor;

[0026] The eleventh MOS transistor is connected to the twelfth MOS transistor;

[0027] The twelfth MOS transistor is connected to the fifth control signal port.

[0028] In another embodiment, the voltage stabilizing circuit includes a first voltage stabilizing diode, a fourth resistor, a fifth resistor, a first diode, and a second diode;

[0029] One end of the voltage stabilizing diode is connected to the fourth resistor and the first diode, and the other end is grounded;

[0030] The fourth resistor is connected to the fourth control signal port through the fifth resistor;

[0031] The first diode is connected to the charge pump circuit through the second diode.

[0032] In another embodiment, a fuse is provided between the positive terminal driving circuit of the protection board and the lithium battery.

[0033] Compared with the prior art, the present invention has the following advantages:

[0034] The positive terminal protection driving control circuit of the lithium battery protection board of the present invention includes a charge pump circuit, a positive terminal driving circuit of the protection board, and a charging voltage acquisition circuit; the charge pump circuit is connected to the positive terminal driving circuit of the protection board and the lithium battery; the positive terminal driving circuit of the protection board is connected to the charge pump circuit, the charging voltage acquisition circuit, and the lithium battery; the charging voltage acquisition circuit is connected to the charge pump circuit and the positive terminal driving circuit of the protection board. This application can have high flexibility while providing protection functions, and corresponding components can be changed according to needs without replacing the whole. The circuit supports soft start, has a small starting current, improves the service life of components while ensuring the stable quality of the product, and the DC bias voltage introduced in the circuit can optimize the static characteristics of transistors. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings used in the description of the embodiments or the prior art. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0036] Figure 1 It is a schematic structural diagram of an embodiment of the positive terminal protection driving control circuit of the lithium battery protection board of the present invention;

[0037] Figure 2 It is a circuit diagram of an embodiment of the charge pump circuit of the present invention;

[0038] Figure 3It is a circuit diagram of an embodiment of the positive terminal drive circuit of the protection board of the present invention;

[0039] Figure 4 It is a circuit diagram of an embodiment of the charging voltage acquisition circuit of the present invention.

[0040] In the figure, 2 is the charge pump circuit, 3 is the positive terminal drive circuit of the protection board, and 4 is the charging voltage acquisition circuit. Detailed implementation manners

[0041] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of the present invention.

[0042] The following further describes in detail a positive terminal protection drive control circuit for a lithium battery protection board provided by the present invention with reference to the accompanying drawings and embodiments.

[0043] As Figure 1 , Figure 2 shown, the positive terminal protection drive control circuit of the lithium battery protection board in this embodiment includes:

[0044] A charge pump circuit 2, a positive terminal drive circuit 3 of the protection board, and a charging voltage acquisition circuit 4;

[0045] The charge pump circuit 2 is connected to the positive terminal drive circuit 3 of the protection board and the lithium battery, and the charge pump circuit 2 is used to boost the voltage for the positive terminal drive circuit 3 of the protection board;

[0046] The positive terminal drive circuit 3 of the protection board is connected to the charge pump circuit 2, the charging voltage acquisition circuit 4, and the lithium battery. When the lithium battery is in an overcharge state, the positive terminal drive circuit 3 of the protection board stops charging after receiving a shutdown discharge signal. When the lithium battery is in an overdischarge state, the positive terminal drive circuit 3 of the protection board stops discharging after receiving a shutdown discharge signal;

[0047] The charging voltage acquisition circuit 4 is connected to the charge pump circuit 2 and the positive terminal drive circuit 3 of the protection board, and is used to detect the charging voltage of the lithium battery.

[0048] As Figure 3 shown, the positive terminal drive circuit 3 of the protection board includes:

[0049] The first MOS transistor Q1, the second MOS transistor Q2, the third MOS transistor Q3, the protection circuit U1, the fifth MOS transistor Q12, the sixth MOS transistor Q14, the seventh MOS transistor Q10, the eighth MOS transistor Q15, the ninth MOS transistor Q17, the tenth MOS transistor Q13, the first control signal port CHG, the second control signal port CO2, the third control signal port DSG, the first power output terminal P+;

[0050] The first MOS transistor Q1 is connected to the second MOS transistor Q2, the protection circuit U1, the fifth MOS transistor Q12, the seventh MOS transistor Q10, and the lithium battery;

[0051] The second MOS transistor Q2 is connected to the third MOS transistor Q3 and the seventh MOS transistor Q10;

[0052] The third MOS transistor Q3 is connected to the ninth MOS transistor Q17, the tenth MOS transistor Q13, and the first power output terminal P+;

[0053] The fifth MOS transistor Q12 is connected to the sixth MOS transistor Q14, the seventh MOS transistor Q10, the tenth MOS transistor Q13, and the charge pump circuit 2;

[0054] The seventh MOS transistor Q10 is connected to the eighth MOS transistor Q15;

[0055] The sixth MOS transistor Q14 is connected to the eighth MOS transistor Q15;

[0056] The sixth MOS transistor Q14 and the eighth MOS transistor Q15 are connected to the first control signal port CHG;

[0057] The ninth MOS transistor Q17 is connected to the tenth MOS transistor Q13 and the third control signal port DSG;

[0058] The protection circuit U1 is connected to the second control signal port CO2.

[0059] The protection circuit U1 includes: a fourth MOS transistor Q8, a first resistor R14, a second resistor R18, and a third resistor R19;

[0060] The first resistor R14 is connected to the drain of the fourth MOS transistor Q8, the second resistor R18 is connected to the gate of the fourth MOS transistor Q8, and the third resistor R19 is connected to the gate and source of the fourth MOS transistor Q8;

[0061] The second resistor R18 is connected to the second control signal port CO2.

[0062] As Figure 4As shown in the figure, the charging voltage acquisition circuit 4 includes: a voltage stabilization circuit U2, an eleventh MOS transistor Q20, a twelfth MOS transistor Q21, a fourth control signal port CH_DET, and a fifth control signal port ADC_EN;

[0063] The voltage stabilization circuit U2 is connected to the charge pump circuit 2, the fourth control signal port CH_DET, and the eleventh MOS transistor Q20;

[0064] The eleventh MOS transistor Q20 is connected to the twelfth MOS transistor Q21;

[0065] The twelfth MOS transistor Q21 is connected to the fifth control signal port ADC_EN.

[0066] The voltage stabilization circuit U2 includes a first voltage stabilizing diode ZD4, a fourth resistor R41, a fifth resistor R42, a first diode D11, and a second diode D10;

[0067] One end of the first voltage stabilizing diode ZD4 is connected to the fourth resistor R41 and the first diode D11, and the other end is grounded;

[0068] The fourth resistor R41 is connected to the fourth control signal port CH_DET through the fifth resistor R42;

[0069] The first diode D11 is connected to the charge pump circuit 1 through the second diode D10.

[0070] A fuse is provided between the positive terminal drive circuit 3 of the protection board and the lithium battery.

[0071] The specific working principle of the positive terminal protection drive control circuit of the lithium battery protection board in this application is as follows:

[0072] The charge pump circuit 2 is used to boost the voltage of the circuit. The charge pump circuit 2 can output a higher voltage to meet the requirements of the positive terminal drive circuit 3 of the protection board.

[0073] At Figure 3In it, the first MOS transistor Q1 is a secondary charging MOS transistor, the second MOS transistor Q2 is a primary charging MOS transistor, and the third MOS transistor Q3 is a discharging MOS transistor. When charging is required, a high level is input to the first control signal port CHG, and the sixth MOS transistor Q14 and the eighth MOS transistor Q15 will conduct, and respectively pull down the gates of the fifth MOS transistor Q12 and the seventh MOS transistor Q10 to a low level, and the fifth MOS transistor Q12 and the seventh MOS transistor Q10 will conduct. The voltages on the gates of the first MOS transistor Q1 and the second MOS transistor Q2 will become the output voltage of the charge pump circuit 2, thereby turning on the positive terminal driving circuit 3 of the protection board. The protection circuit U1 is composed of the fourth MOS transistor Q8, the first resistor R14, the second resistor R18, and the third resistor R19, and is a secondary control protection circuit for the positive terminal driving circuit 3 of the protection board, used to prevent the positive terminal driving circuit 3 of the protection board from not being able to be normally turned off when the control voltage of the first control signal port CHG is abnormal. When secondary charging overvoltage occurs, inputting a high level to the second control signal port CO2 can make the fourth MOS transistor Q8 conduct. At this time, regardless of the state of the gate of the first MOS transistor Q1, it will be pulled down to a low level, thereby turning off the first MOS transistor Q1 and turning off the charging.

[0074] When discharging is required, input a high level to the third control signal port DSG, and the ninth MOS transistor Q17 will conduct, pulling down the base of the triode Q11 to a low level, thereby making the triode Q11 conduct. The gate of the third MOS transistor Q3 will become the output voltage of the charge pump circuit 2, making the third MOS transistor Q3 turn on for discharging.

[0075] Figure 4 In it, when the voltage of the first power output terminal P+ needs to be detected, when a high level is input to the fifth control signal port ADC_EN, the twelfth MOS transistor Q21 will conduct, pulling down the gate of the eleventh MOS transistor Q20 to a low level, making the eleventh MOS transistor Q20 conduct. The loop where the eleventh MOS transistor Q20 is located is connected to the charging loop. At this time, detecting the voltage of the fourth control signal port CH_DET can know the voltage of the first power output terminal P+. When it is detected that the battery voltage is too low, the charging voltage acquisition circuit 4 will be continuously turned on, and the voltage stabilizing circuit U2 composed of the first zener diode ZD4, the fourth resistor R41, and the fifth resistor R42 supplies power to the charge pump circuit 2 through the first diode D11 and the second diode D10.

[0076] The above has introduced in detail a positive terminal protection drive control circuit for a lithium battery protection board. In this article, specific examples are used to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present invention.

[0077] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A positive terminal protection drive control circuit for a lithium battery protection board, characterized in that, Including: A charge pump circuit, a positive terminal driving circuit of the protection board, and a charging voltage acquisition circuit; The charge pump circuit is connected to the positive terminal driving circuit of the protection board and the lithium battery, and the charge pump circuit is used to boost the voltage for the positive terminal driving circuit of the protection board; The positive terminal driving circuit of the protection board is connected to the charge pump circuit, the charging voltage acquisition circuit, and the lithium battery. When the lithium battery is in an overcharge state, the positive terminal driving circuit of the protection board stops charging after receiving a charging-off signal. When the lithium battery is in an over-discharge state, the positive terminal driving circuit of the protection board stops discharging after receiving a discharge-off signal; The charging voltage acquisition circuit is connected to the charge pump circuit and the positive terminal driving circuit of the protection board, and is used to detect the charging voltage of the lithium battery; The positive terminal driving circuit of the protection board includes: A first MOS transistor, a second MOS transistor, a third MOS transistor, a protection circuit, a fifth MOS transistor, a sixth MOS transistor, a seventh MOS transistor, an eighth MOS transistor, a ninth MOS transistor, a tenth MOS transistor, a first control signal port, a second control signal port, a third control signal port, and a first power output terminal; The first MOS transistor is connected to the second MOS transistor, the protection circuit, the fifth MOS transistor, the seventh MOS transistor, and the lithium battery; The second MOS transistor is connected to the third MOS transistor and the seventh MOS transistor; The third MOS transistor is connected to the ninth MOS transistor, the tenth MOS transistor, and the first power output terminal; The fifth MOS transistor is connected to the sixth MOS transistor, the seventh MOS transistor, the tenth MOS transistor, and the charge pump circuit; The seventh MOS transistor is connected to the eighth MOS transistor; The sixth MOS transistor is connected to the eighth MOS transistor; The sixth MOS transistor and the eighth MOS transistor are connected to the first control signal port; The ninth MOS transistor is connected to the tenth MOS transistor and the third control signal port; The protection circuit is connected to the second control signal port.

2. The circuit according to claim 1, wherein The protection circuit includes: a fourth MOS transistor, a first resistor, a second resistor, and a third resistor; The first resistor is connected to the drain of the fourth MOS transistor, the second resistor is connected to the gate of the fourth MOS transistor, and the third resistor is connected to the gate and the source of the fourth MOS transistor; The second resistor is connected to the second control signal port.

3. The circuit according to claim 1, wherein The charging voltage acquisition circuit includes: a voltage stabilizing circuit, an eleventh MOS transistor, a twelfth MOS transistor, a fourth control signal port, and a fifth control signal port; The voltage stabilizing circuit is connected to the charge pump circuit, the fourth control signal port, and the eleventh MOS transistor; The eleventh MOS transistor is connected to the twelfth MOS transistor; The twelfth MOS transistor is connected to the fifth control signal port.

4. The circuit according to claim 3, characterized in that, The voltage stabilizing circuit includes a first zener diode, a fourth resistor, a fifth resistor, a first diode, and a second diode; One end of the zener diode is connected to the fourth resistor and the first diode, and the other end is grounded; The fourth resistor is connected to the fourth control signal port through the fifth resistor; The first diode is connected to the charge pump circuit through the second diode.

5. The circuit according to claim 1, characterized in that, A fuse is arranged between the positive terminal driving circuit of the protection board and the lithium battery.

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