A battery charging and discharging control circuit, power supply device and mobile terminal

Abstract

The present disclosure relates to a battery charge and discharge control circuit, a power supply device and a mobile terminal. The battery charge and discharge control circuit includes: a current limiting module, a voltage control module and a control module; the first end of the current limiting module is electrically connected to the positive end of the first battery, the second end of the current limiting module is electrically connected to the positive end of the second battery, the control end of the current limiting module is electrically connected to the output end of the voltage control module, the output end of the control module is electrically connected to the input end of the voltage control module, and the second end of the current limiting module is also electrically connected to the charge and discharge circuit; the current limiting module is used to limit the charge and discharge current of the first battery. The present disclosure makes the charge and discharge current of the first battery adjustable during the charge and discharge process, and only needs to control the charge and discharge current of the first battery, with low control cost and high efficiency.

Description

Technical Field

[0001] The present disclosure relates to the field of battery technology, and in particular to a battery charging and discharging control circuit, a power supply device and a mobile terminal. Background Art

[0002] For currently commonly used electronic devices, in order to maximize the battery capacity, two batteries are usually connected in parallel to expand the battery pack capacity of the electronic device. However, various problems will arise when two batteries with large differences in capacity are charged and discharged in parallel. For example, during the charging process, one battery may be overcharged or over-discharged with a large current for a long time, affecting the safety and service life of the battery. In order to solve the above problems, in the prior art, the charging and discharging currents of the two batteries are usually controlled separately to solve the battery charging and discharging problems encountered, but the cost of controlling the charging and discharging circuits of the two batteries at the same time is high and the efficiency is very low. Utility Model Content

[0003] In order to solve the above technical problems or at least partially solve the above technical problems, the present disclosure provides a battery charge and discharge control circuit, a power supply device and a mobile terminal, so that the charge and discharge current of the first battery during the charge and discharge process is adjustable, thereby avoiding the problem of excessive instantaneous current due to simultaneous charging and discharging of the first battery and the second battery, and only the charge and discharge current of the first battery is controlled, with low control cost and high efficiency.

[0004] The embodiment of the present disclosure provides a battery charge and discharge control circuit, including: a current limiting module, a voltage control module and a control module;

[0005] The first end of the current limiting module is electrically connected to the positive end of the first battery, the second end of the current limiting module is electrically connected to the positive end of the second battery, the control end of the current limiting module is electrically connected to the output end of the voltage control module, the output end of the control module is electrically connected to the input end of the voltage control module, and the second end of the current limiting module is also electrically connected to the charge and discharge circuit;

[0006] The current limiting module is used to limit the charging and discharging current of the first battery.

[0007] Optionally, a voltage detection module is also included;

[0008] The first detection end of the voltage detection module is electrically connected to the positive end of the first battery, the second detection end of the voltage detection module is electrically connected to the positive end of the second battery, and the output end of the voltage detection module is electrically connected to the input end of the control module.

[0009] Optionally, the current limiting module includes: at least one switch unit and a current control unit;

[0010] The first end of the current control unit is electrically connected to the positive end of the first battery, the second end of the current control unit is electrically connected to the positive end of the second battery, and the second end of the current control unit is also connected to the charge and discharge circuit; the control end of the switch unit is electrically connected to the output end of the voltage control module, the first end of the switch unit is electrically connected to the positive end of the first battery, and the second end of the switch unit is electrically connected to the charge and discharge circuit.

[0011] Optionally, the current control unit includes a first resistor.

[0012] Optionally, the switch unit includes: a first NMOS tube;

[0013] The gate of the first NMOS tube is electrically connected to the output end of the voltage control module, the first electrode of the first NMOS tube is electrically connected to the positive terminal of the first battery, and the second electrode of the first NMOS tube is electrically connected to the charge and discharge circuit.

[0014] Optionally, the switch unit includes: a second NMOS tube and a third NMOS tube;

[0015] The gate of the second NMOS tube is electrically connected to the first output end of the voltage control module, the gate of the third NMOS tube is electrically connected to the second output end of the voltage control module, the source of the second NMOS tube is electrically connected to the positive terminal of the first battery, the drain of the second NMOS tube is electrically connected to the drain of the third NMOS tube, and the source of the third NMOS tube is electrically connected to the charge and discharge circuit.

[0016] Optionally, the voltage control module is a boost control circuit.

[0017] Optionally, the switch unit includes: a first PMOS tube;

[0018] The gate of the first PMOS tube is electrically connected to the output end of the voltage control module, the first electrode of the first PMOS tube is electrically connected to the positive terminal of the first battery, and the second electrode of the first PMOS tube is electrically connected to the charge and discharge circuit.

[0019] An embodiment of the present disclosure also provides a power supply device, comprising any battery charge and discharge control circuit as described above.

[0020] The embodiment of the present disclosure also provides a mobile terminal, comprising the power supply device as described above.

[0021] Compared with the prior art, the technical solution provided by the embodiments of the present disclosure has the following advantages:

[0022] The disclosed embodiment provides a battery charge and discharge control circuit, a power supply device and a mobile terminal. By setting a current limiting module between the first battery and the charge and discharge circuit, the voltage provided to the current limiting module is adjusted by the voltage control module to adjust the current flowing through the current limiting module, so that the current limiting module can limit the current size of the first battery during the charge and discharge process, so that the first battery will not complete charging or discharging too early compared to the second battery during the charge and discharge process, thereby avoiding the first battery from being overcharged or over-discharged for a long time, and ensuring the safety and service life of the first battery. It can also avoid that when the first battery and the second battery are first installed in the electronic device, the first battery is filled with current from the second battery due to the different power, causing the first battery to be damaged. In addition, the disclosed embodiment controls the current of the first battery only through the current limiting module, so that the control cost is reduced and the efficiency is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0025] Figure 1 A schematic diagram of a battery charging and discharging control circuit provided in an embodiment of the present disclosure;

[0026] Figure 2 A schematic diagram of another battery charge and discharge control circuit provided in an embodiment of the present disclosure;

[0027] Figure 3 A schematic diagram of another battery charge and discharge control circuit provided in an embodiment of the present disclosure;

[0028] Figure 4 A schematic diagram of another battery charge and discharge control circuit provided in an embodiment of the present disclosure;

[0029] Figure 5 A schematic diagram of another battery charge and discharge control circuit provided in an embodiment of the present disclosure;

[0030] Figure 6 A schematic diagram of another battery charging and discharging control circuit provided in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0031] In order to more clearly understand the above-mentioned objectives, features and advantages of the present disclosure, the scheme of the present disclosure will be further described below. It should be noted that the embodiments of the present disclosure and the features in the embodiments can be combined with each other without conflict.

[0032] In the following description, many specific details are set forth to facilitate a full understanding of the present disclosure, but the present disclosure may also be implemented in other ways different from those described herein; it is obvious that the embodiments in the specification are only part of the embodiments of the present disclosure, rather than all of the embodiments.

[0033] Figure 1 A schematic diagram of a battery charging and discharging control circuit provided by an embodiment of the present disclosure is shown in FIG. Figure 1 As shown, the battery charge and discharge control circuit includes: a current limiting module 100 , a voltage control module 200 and a control module 300 .

[0034] The first end 101 of the current limiting module 100 is electrically connected to the positive terminal 411 of the first battery 410, the second end 102 of the current limiting module 100 is electrically connected to the positive terminal 421 of the second battery 420, the negative terminal 412 of the first battery 410 and the negative terminal 422 of the second battery 420 are both grounded, the control end 103 of the current limiting module 100 is electrically connected to the output end 201 of the voltage control module 200, the output end 301 of the control module 300 is electrically connected to the input end 202 of the voltage control module 200, and the second end 102 of the current limiting module 100 is also electrically connected to the charge and discharge circuit 500.

[0035] The current limiting module 100 is used to limit the magnitude of the current flowing to the first battery 410 , and to limit the magnitude of the current flowing out of the first battery 410 .

[0036] Exemplarily, the rated capacity of the first battery 410 is smaller than the rated capacity of the second battery 420. When the electronic device is not started, since the voltage of the second battery 420 is higher than the voltage of the first battery 410, when the first battery 410 and the second battery 420 are just placed in the electronic device, the second battery 420 will output current to the first battery 410, so the output current of the second battery 420 can be limited by the current limiting module 100 to prevent the first battery 410 from being damaged by excessive current. When the electronic device starts normally and begins to be used, since the rated capacity of the first battery 410 is lower than the rated capacity of the second battery 420, if the first battery 410 and the second battery 420 are discharged with the same current, the first battery 410 will continue to discharge after normally discharging to the cut-off voltage, so that the service life of the first battery 410 is affected. Therefore, the output voltage of the voltage control module 200 can be controlled by the control module 300, so that the current limiting module 100 limits the discharge current of the first battery 410 to avoid the first battery 410 from discharging too fast, and try to ensure that the first battery 410 and the second battery 420 can complete the discharge at the same time. When the electronic device starts to charge, since the rated capacity of the first battery 410 is lower than the rated capacity of the second battery 420, if the first battery 410 and the second battery 420 are charged with the same current, the first battery 410 will continue to be charged after it is fully charged, which will affect the service life of the first battery 410. Therefore, the output voltage of the voltage control module 200 can be controlled by the control module 300, so that the current limiting module 100 limits the charging current of the first battery 410 to avoid the first battery 410 from charging too fast, and try to ensure that the first battery 410 and the second battery 420 can be charged at the same time.

[0037] It should be noted that the rated capacity of the first battery being smaller than the rated capacity of the second battery is only an example of the present disclosure, and the rated capacity of the first battery may also be equal to the rated capacity of the second battery, which is determined according to actual conditions and is not specifically limited here.

[0038] Therefore, the embodiment of the present disclosure sets a current limiting module 100 between the first battery 410 and the charge and discharge circuit 500, and adjusts the voltage provided to the current limiting module 100 through the voltage control module 200 to adjust the current flowing through the current limiting module 100, so that the current limiting module 100 can limit the current size of the first battery 410 during the charge and discharge process, so that the first battery 410 will not complete charging or discharging too early compared to the second battery 420 during the charge and discharge process, thereby avoiding the first battery 410 from being overcharged or over-discharged for a long time, and ensuring the safety and service life of the first battery 410. It can also avoid that when the first battery 410 and the second battery 420 are first installed in the electronic device, the first battery 410 is injected with the current from the second battery 420 due to the different power, causing the first battery 410 to be damaged. In addition, the embodiment of the present disclosure controls the current of the first battery 410 only through the current limiting module 100, so that the control cost is reduced and the efficiency is improved.

[0039] In some embodiments, Figure 2 A schematic diagram of another battery charging and discharging control circuit provided by an embodiment of the present disclosure is shown in FIG. Figure 2 As shown, the battery charge and discharge control circuit further includes a voltage detection module 600 .

[0040] The first detection terminal 601 of the voltage detection module 600 is electrically connected to the positive terminal 411 of the first battery 410 , the second detection terminal 602 of the voltage detection module 600 is electrically connected to the positive terminal 421 of the second battery 420 , and the output terminal 603 of the voltage detection module 600 is electrically connected to the input terminal 302 of the control module 300 .

[0041] Exemplarily, the rated capacity of the first battery 410 is less than the rated capacity of the second battery 420. When the electronic device is normally started and begins to be used, the voltage of the first battery 410 and the second battery 420 are first detected by the voltage detection module 600, and the detected voltages are sent to the control module 300 for comparison. When it is detected that the voltage of the first battery 410 is less than the voltage of the second battery 420, the control module 300 controls the output voltage of the voltage control module 200, so that the current limiting module 100 limits the discharge current of the first battery 410, so that the discharge speed of the first battery 410 is slowed down, while the discharge speed of the second battery 420 is still kept normal at this time, so that the first battery 410 can slow down the discharge speed to wait for the voltage of the second battery 420 to approach the voltage level of the first battery 410 faster. When it is detected that the voltage of the first battery 410 is greater than or equal to the voltage of the second battery 420, the control module 300 controls the output voltage of the voltage control module 200 so that the current limiting module 100 no longer limits the discharge current of the first battery 410, and the discharge speed of the first battery 410 is restored to a normal speed, thereby enabling the voltage of the first battery 410 to approach the voltage level of the second battery 420 more quickly.

[0042] When the electronic device starts to charge, the voltage detection module 600 is used to detect the voltages of the first battery 410 and the second battery 420 respectively, and the detected voltages are sent to the control module 300 for comparison. When it is detected that the voltage of the first battery 410 is greater than the voltage of the second battery 420, the control module 300 controls the output voltage of the voltage control module 200, so that the current limiting module 100 limits the charging current of the first battery 410, so that the charging current of the first battery 410 is reduced and the charging speed is slowed down, while the charging speed of the second battery 420 remains normal at this time, so that the voltage of the second battery 420 can approach the voltage level of the first battery 410 more quickly. When it is detected that the voltage of the first battery 410 is less than or equal to the voltage of the second battery 420, the control module 300 controls the output voltage of the voltage control module 200, so that the current limiting module 100 does not limit the charging current of the first battery 410, so that the charging current of the first battery 410 returns to normal, so that the voltage of the first battery 410 can approach the voltage level of the second battery 420 more quickly. Thus, the embodiment of the present disclosure realizes limiting the charge and discharge current of the first battery 410 through the current limiting module 100, so that the charge and discharge speeds of the first battery 410 and the second battery 420 can be almost the same, thereby preventing the first battery 410 from being charged or discharged too quickly, thereby preventing the subsequent overcharge and overdischarge, and ensuring the safety and service life of the first battery 410. The embodiment of the present disclosure also detects the voltage of the first battery 410 and the second battery 420 through the voltage detection module 600, further ensuring the accuracy of the current limiting module 100 for the first battery 410. In addition, the embodiment of the present disclosure controls the current of the first battery 410 only through the current limiting module 100, so that the control cost is reduced and the efficiency is improved.

[0043] In some embodiments, Figure 3 A schematic diagram of another battery charging and discharging control circuit provided by an embodiment of the present disclosure is shown in FIG. Figure 3 As shown, the current limiting module 100 includes: at least one switch unit 110 and a current control unit 120 .

[0044] The first end 121 of the current control unit 120 is electrically connected to the positive terminal 411 of the first battery 410, the second end 122 of the current control unit 120 is electrically connected to the positive terminal 421 of the second battery 420, and the second end 122 of the current control unit 120 is also connected to the charge and discharge circuit 500; the control end 111 of the switch unit 110 is electrically connected to the output end 201 of the voltage control module 200, the first end 112 of the switch unit 110 is electrically connected to the positive terminal 411 of the first battery 410, and the second end 113 of the switch unit 110 is electrically connected to the charge and discharge circuit 500.

[0045] Exemplarily, the rated capacity of the first battery 410 is less than the rated capacity of the second battery 420. When the electronic device is not started, the switch unit 110 remains disconnected. When the first battery 410 and the second battery 420 are installed in the electronic device, if the voltage of the second battery 420 is greater than the voltage of the first battery 410, the second battery 420 will transmit current to the first battery 410. Since the switch unit 110 remains disconnected, the current will flow to the first battery 410 through the current control unit 120, and the current control unit 120 will limit the magnitude of the current flowing therethrough to prevent the first battery 410 from being damaged by excessive current.

[0046] When the electronic device starts normally and begins to be used, the voltage detection module 600 is first used to detect the voltages of the first battery 410 and the second battery 420 respectively, and the detected voltages are sent to the control module 300 for comparison. When it is detected that the voltage of the first battery 410 is less than the voltage of the second battery 420, the control module 300 controls the output voltage of the voltage control module 200, and the switch unit 110 is disconnected according to the voltage signal output by the voltage control module 200. At this time, the discharge current of the first battery 410 will be transmitted to the charge and discharge circuit 500 through the current control unit 120, and the current control unit 120 will limit the discharge current of the first battery 410 to slow down the discharge speed of the first battery 410, while the discharge speed of the second battery 420 remains normal at this time, so that the first battery 410 can slow down the discharge speed to wait for the voltage of the second battery 420 to approach the voltage level of the first battery 410 faster. When it is detected that the voltage of the first battery 410 is greater than or equal to the voltage of the second battery 420, the control module 300 controls the output voltage of the voltage control module 200, and the switch unit 110 is turned on according to the voltage signal output by the voltage control module 200. At this time, the discharge current of the first battery 410 will be transmitted to the charge and discharge circuit 500 through the turned-on switch unit 110, so that the discharge speed of the first battery 410 is restored to normal speed, thereby allowing the voltage of the first battery 410 to approach the voltage level of the second battery 420 more quickly.

[0047] When the electronic device starts to charge, the voltage detection module 600 is first used to detect the voltages of the first battery 410 and the second battery 420 respectively, and the detected voltages are sent to the control module 300 for comparison. When it is detected that the voltage of the first battery 410 is greater than the voltage of the second battery 420, the control module 300 controls the output voltage of the voltage control module 200, and the switch unit 110 is disconnected according to the voltage signal output by the voltage control module 200. At this time, the charging current will be transmitted to the first battery 410 through the current control unit 120, and the current control unit 120 will limit the charging current of the first battery 410, so that the charging current of the first battery 410 is reduced and the charging speed is slowed down. At this time, the charging speed of the second battery 420 remains normal, so that the voltage of the second battery 420 can approach the voltage level of the first battery 410 more quickly. When it is detected that the voltage of the first battery 410 is less than or equal to the voltage of the second battery 420, the control module 300 controls the output voltage of the voltage control module 200, and the switch unit 110 is turned on according to the voltage signal output by the voltage control module 200. At this time, the charging current will be transmitted to the first battery 410 through the turned-on switch unit 110, so that the charging speed of the first battery 410 is restored to normal speed, thereby allowing the voltage of the first battery 410 to approach the voltage level of the second battery 420 more quickly.

[0048] Thus, the embodiment of the present disclosure realizes limiting the charge and discharge current of the first battery 410 through the cooperation between the switch unit 110 and the current control unit 120, so that the charge and discharge speeds of the first battery 410 and the second battery 420 can be almost the same, thereby preventing the first battery 410 from being charged or discharged too quickly, thereby preventing the subsequent overcharge and overdischarge, and ensuring the safety and service life of the first battery 410. The embodiment of the present disclosure also detects the voltage of the first battery 410 and the second battery 420 through the voltage detection module 600, further ensuring the accuracy of the current limiting module 100 for the first battery 410. In addition, the embodiment of the present disclosure controls the current of the first battery 410 only through the current limiting module 100, so that the control cost is reduced and the efficiency is improved.

[0049] In some embodiments, the current control unit includes a first resistor.

[0050] Specifically, the current control unit can use a first resistor with a resistance value of 100Ω. Through the cooperation of the switch unit and the first resistor, when the switch unit is turned on, the charge and discharge current of the first battery can be transmitted without restriction through the turned-on switch unit. When the switch unit is disconnected, the charge and discharge current of the first battery can be transmitted through the first resistor, thereby limiting the current size. The charge and discharge speeds of the first battery and the second battery can be almost the same, thereby preventing the first battery from being charged or discharged too quickly, resulting in subsequent overcharging and over-discharging, and ensuring the safety and service life of the first battery.

[0051] In some embodiments, Figure 4 A schematic diagram of another battery charging and discharging control circuit provided by an embodiment of the present disclosure is shown in FIG. Figure 4 As shown, the switch unit includes: a first NMOS tube Q1.

[0052] The gate of the first NMOS transistor Q1 is electrically connected to the output terminal 201 of the voltage control module 200 , the first electrode of the first NMOS transistor Q1 is electrically connected to the positive terminal 411 of the first battery 410 , and the second electrode of the first NMOS transistor Q1 is electrically connected to the charge and discharge circuit 500 .

[0053] Exemplarily, the rated capacity of the first battery 410 is less than the rated capacity of the second battery 420. When the electronic device is not started, the first NMOS tube Q1 remains disconnected. When the first battery 410 and the second battery 420 are installed in the electronic device, if the voltage of the second battery 420 is greater than the voltage of the first battery 410, the second battery 420 will transmit current to the first battery 410. Since the first NMOS tube Q1 remains disconnected, the current will flow to the first battery 410 through the current control unit 120, and the current control unit 120 will limit the current flowing through to avoid excessive current from damaging the first battery 410.

[0054] When the electronic device starts normally and begins to be used, the voltage detection module 600 is first used to detect the voltages of the first battery 410 and the second battery 420 respectively, and the detected voltages are sent to the control module 300 for comparison. When it is detected that the voltage of the first battery 410 is lower than the voltage of the second battery 420, the control module 300 controls the voltage control module 200 to output a low-level signal, and the first and second poles of the first NMOS tube Q1 are disconnected. At this time, the discharge current of the first battery 410 will be transmitted to the charge and discharge circuit 500 through the current control unit 120, and the current control unit 120 will limit the discharge current of the first battery 410, so that the first battery 410 slows down the discharge speed, waiting for the voltage of the second battery 420 to approach the voltage level of the first battery 410 faster. When it is detected that the voltage of the first battery 410 is greater than or equal to the voltage of the second battery 420, the control module 300 controls the output high-level signal of the voltage control module 200, and the first electrode and the second electrode of the first NMOS tube Q1 are turned on. At this time, the discharge current of the first battery 410 will be transmitted to the charge and discharge circuit 500 through the turned-on first NMOS tube Q1, so that the discharge speed of the first battery 410 is restored to a normal speed, thereby allowing the voltage of the first battery 410 to approach the voltage level of the second battery 420 more quickly.

[0055] When the electronic device starts to charge, the voltage detection module 600 is used to detect the voltages of the first battery 410 and the second battery 420 respectively, and the detected voltages are sent to the control module 300 for comparison. When it is detected that the voltage of the first battery 410 is greater than the voltage of the second battery 420, the control module 300 controls the output low-level signal of the voltage control module 200, and the first pole and the second pole of the first NMOS tube Q1 are disconnected. At this time, the charging current will be transmitted to the first battery 410 through the current control unit 120, and the current control unit 120 will limit the charging current of the first battery 410, so that the charging current of the first battery 410 is reduced and the charging speed is slowed down. At this time, the charging speed of the second battery 420 remains normal, so that the voltage of the second battery 420 can approach the voltage level of the first battery 410 more quickly. When it is detected that the voltage of the first battery 410 is less than or equal to the voltage of the second battery 420, the control module 300 controls the output high-level signal of the voltage control module 200, and the first electrode and the second electrode of the first NMOS tube Q1 are turned on. At this time, the charging current will be transmitted to the first battery 410 through the turned-on first NMOS tube Q1, so that the charging speed of the first battery 410 is restored to normal speed, thereby allowing the voltage of the first battery 410 to approach the voltage level of the second battery 420 more quickly.

[0056] In some embodiments, Figure 5A schematic diagram of another battery charging and discharging control circuit provided by an embodiment of the present disclosure is shown in FIG. Figure 5 As shown, the switch unit includes: a second NMOS tube Q2 and a third NMOS tube Q3.

[0057] The gate of the second NMOS tube Q2 is electrically connected to the first output terminal 202 of the voltage control module 200, the gate of the third NMOS tube Q3 is electrically connected to the second output terminal 203 of the voltage control module 200, the source of the second NMOS tube Q2 is electrically connected to the positive terminal 411 of the first battery 410, the drain of the second NMOS tube Q2 is electrically connected to the drain of the third NMOS tube Q3, and the source of the third NMOS tube Q3 is electrically connected to the charge and discharge circuit 500.

[0058] Exemplarily, the rated capacity of the first battery 410 is less than the rated capacity of the second battery 420. When the electronic device is in the off state, if the voltage in the first battery 410 or the second battery 420 is higher than the voltage of the other battery, the battery with the larger voltage will output current to the battery with the smaller voltage. At this time, the second NMOS tube Q2 and the third NMOS tube Q3 are kept in the disconnected state, and the first battery 410 and the second battery 420 limit the current output by the battery through the current control unit 120. The current after limitation can be less than 20mA. Therefore, the first battery 410 and the second battery 420 balance the voltages of the two through the current control unit to avoid large current discharge and affect the battery life.

[0059] When the electronic device is turned on and used normally, the voltage detection module 600 detects the voltages of the first battery 410 and the second battery 420. When it is detected that the voltage of the first battery 410 is lower than the voltage of the second battery 420, the control module 300 controls the voltage control module 200 to output a low-level signal, and the second NMOS tube Q2 and the third NMOS tube Q3 are both disconnected. At this time, the discharge current of the first battery 410 is transmitted to the charge and discharge circuit 500 through the current control unit 120, and the current control unit 120 limits the discharge current of the first battery 410, so that the first battery 410 slows down the discharge speed, waiting for the voltage of the second battery 420 to approach the voltage level of the first battery 410 faster. When it is detected that the voltage of the first battery 410 is greater than or equal to the voltage of the second battery 420, the control module 300 controls the output high-level signal of the voltage control module 200, and the second NMOS tube Q2 and the third NMOS tube Q3 are both turned on. At this time, the discharge current of the first battery 410 will be transmitted to the charge and discharge circuit 500 through the turned-on second NMOS tube Q2 and the third NMOS tube Q3, so that the discharge speed of the first battery 410 is restored to the normal speed, thereby enabling the voltage of the first battery 410 to more quickly approach the voltage level of the second battery 420. In addition, the current flowing through the second NMOS tube Q2 and the third NMOS tube Q3 can also be set to no more than 1A through the voltage control module 200, thereby preventing the first battery 410 from discharging too fast during normal discharge.

[0060] When the electronic device starts to charge, pre-charging is performed first, and the second NMOS tube Q2 and the third NMOS tube Q3 are controlled to be disconnected, so as to limit the charging current of the first battery 410, and make the charging and discharging circuit 500 mainly pre-charge the second battery 420, so that the pre-charging is completed quickly and the charging prompt is displayed.

[0061] Then, constant current charging is performed. The voltage of the first battery 410 and the second battery 420 is detected by the voltage detection module 600. When the voltage of the first battery 410 is greater than the voltage of the second battery 420, the second NMOS tube Q2 and the third NMOS tube Q3 are controlled to be disconnected, and the charge and discharge circuit 500 mainly charges the second battery 420. When the voltage of the first battery 410 is less than the voltage of the second battery 420, and the voltage of the first battery 410 is less than 3.1V, the second NMOS tube Q2 and the third NMOS tube Q3 are controlled to be turned on, and the current flowing through the second NMOS tube Q2 and the third NMOS tube Q3 is limited by the voltage control module 200, and the charging current is controlled to be 100mA, so that the first battery 410 enters the pre-charging mode. Only when the voltage of the first battery 410 is greater than or equal to 3.1V, the charging current is set to 1.5V, so that the first battery 410 is also charged with constant current.

[0062] Finally, constant voltage charging is performed, and the voltages of the first battery 410 and the second battery 420 are detected by the voltage detection module 600. When the voltage of the first battery 410 is greater than the voltage of the second battery 420, the second NMOS tube Q2 and the third NMOS tube Q3 are controlled to be disconnected. At this time, the charging current will be transmitted to the first battery 410 through the current control unit 120, and the current control unit 120 will limit the charging current of the first battery 410, so that the charging current of the first battery 410 is reduced and the charging speed is slowed down. At this time, the charging speed of the second battery 420 remains normal, so that the voltage of the second battery 420 can approach the voltage level of the first battery 410 more quickly. When it is detected that the voltage of the first battery 410 is less than or equal to the voltage of the second battery 420, the control module 300 controls the output high-level signal of the voltage control module 200 to control the second NMOS tube Q2 and the third NMOS tube Q3 to be turned on. At this time, the charging current will be transmitted to the first battery 410 through the turned-on second NMOS tube Q2 and the third NMOS tube Q3. The voltage control module 200 sets the current flowing through the second NMOS tube Q2 and the third NMOS tube Q3 to 500mA, so that the charging speed of the first battery 410 is restored to the normal speed, thereby allowing the voltage of the first battery 410 to approach the voltage level of the second battery 420 more quickly.

[0063] Thus, the embodiment of the present disclosure realizes limiting the charge and discharge current of the first battery 410 through the cooperation of the second NMOS tube Q2, the third NMOS tube Q3 and the current control unit 120, so that the charge and discharge speeds of the first battery 410 and the second battery 420 can be almost consistent, thereby preventing the first battery 410 from being charged or discharged too quickly, thereby preventing the subsequent overcharge and overdischarge phenomenon, and ensuring the safety and service life of the first battery 410. The embodiment of the present disclosure controls the current of the first battery 410 only through the current limiting module 100, so that the control cost is reduced and the efficiency is improved.

[0064] The disclosed embodiment also sets two NMOS tubes, and connects the drain of the second NMOS tube Q2 to the drain of the third NMOS tube Q3, so that the second NMOS tube Q2 and the third NMOS tube Q3 are set back to back. Since the second NMOS tube Q2 and the third NMOS tube Q3 are both provided with parasitic diodes, when the second NMOS tube Q2 and the third NMOS tube Q3 are both disconnected, the positive and negative directions of the parasitic diode in the second NMOS tube Q2 are opposite to the positive and negative directions of the parasitic diode in the third NMOS tube Q3, so that the current in the circuit cannot pass through the two parasitic diodes at the same time, further ensuring that when the second NMOS tube Q2 and the third NMOS tube Q3 are both disconnected, no current passes through the branch where the second NMOS tube Q2 and the third NMOS tube Q3 are located.

[0065] In some embodiments, the voltage control module is a boost control circuit.

[0066] Specifically, the voltage control module can adopt a boost control circuit, which can control the on and off of the connected NMOS tube and limit the current flowing through the NMOS tube after it is turned on, thereby further ensuring that the battery safety and life of the battery will not be affected by excessive charge and discharge current during the charging process.

[0067] In some embodiments, Figure 6 A schematic diagram of another battery charging and discharging control circuit provided by an embodiment of the present disclosure is shown in FIG. Figure 6 As shown, the switch unit includes: a first PMOS tube Q4.

[0068] The gate of the first PMOS transistor Q4 is electrically connected to the output terminal 201 of the voltage control module 200 , the first electrode of the first PMOS transistor Q4 is electrically connected to the positive terminal 411 of the first battery 410 , and the second electrode of the first PMOS transistor Q4 is electrically connected to the charge and discharge circuit 500 .

[0069] Exemplarily, the rated capacity of the first battery 410 is less than the rated capacity of the second battery 420. When the electronic device is not started, the first PMOS tube Q4 remains disconnected. When the first battery 410 and the second battery 420 are installed in the electronic device, if the voltage of the second battery 420 is greater than the voltage of the first battery 410, the second battery 420 will transmit current to the first battery 410. Since the first PMOS tube Q4 remains disconnected, the current will flow to the first battery 410 through the current control unit 120, and the current control unit 120 will limit the magnitude of the current flowing through to avoid excessive current from damaging the first battery 410.

[0070] When the electronic device is started normally and begins to be used, the voltage of the first battery 410 and the second battery 420 are first detected by the voltage detection module 600, and the detected voltages are sent to the control module 300 for comparison. When it is detected that the voltage of the first battery 410 is lower than the voltage of the second battery 420, the control module 300 controls the voltage control module 200 to output a high-level signal, and the first and second electrodes of the first PMOS tube Q4 are disconnected. At this time, the discharge current of the first battery 410 will be transmitted to the charge and discharge circuit 500 through the current control unit 120, and the current control unit 120 will limit the discharge current of the first battery 410, so that the first battery 410 slows down the discharge speed, waiting for the voltage of the second battery 420 to approach the voltage level of the first battery 410 faster. When it is detected that the voltage of the first battery 410 is greater than or equal to the voltage of the second battery 420, the control module 300 controls the output low-level signal of the voltage control module 200, and the first electrode and the second electrode of the first PMOS tube Q4 are turned on. At this time, the discharge current of the first battery 410 will be transmitted to the charge and discharge circuit 500 through the turned-on first PMOS tube Q4, so that the discharge speed of the first battery 410 is restored to the normal speed, thereby allowing the voltage of the first battery 410 to approach the voltage level of the second battery 420 more quickly.

[0071] When the electronic device starts to charge, the voltage detection module 600 is first used to detect the voltages of the first battery 410 and the second battery 420 respectively, and the detected voltages are sent to the control module 300 for comparison. When it is detected that the voltage of the first battery 410 is greater than the voltage of the second battery 420, the control module 300 controls the voltage control module 200 to output a high-level signal, and the first and second poles of the first PMOS tube Q4 are disconnected. At this time, the charging current will be transmitted to the first battery 410 through the current control unit 120, and the current control unit 120 will limit the charging current of the first battery 410, so that the charging current of the first battery 410 is reduced and the charging speed is slowed down. At this time, the charging speed of the second battery 420 remains normal, so that the voltage of the second battery 420 can approach the voltage level of the first battery 410 more quickly. When it is detected that the voltage of the first battery 410 is less than or equal to the voltage of the second battery 420, the control module 300 controls the output low-level signal of the voltage control module 200, and the first pole and the second pole of the first PMOS tube Q4 are turned on. At this time, the charging current will be transmitted to the first battery 410 through the turned-on first PMOS tube Q4, so that the charging speed of the first battery 410 is restored to the normal speed, thereby allowing the voltage of the first battery 410 to approach the voltage level of the second battery 420 more quickly.

[0072] An embodiment of the present disclosure also provides a power supply device, comprising any of the above-mentioned battery charge and discharge control circuits.

[0073] The power supply device disclosed in the above embodiment and the battery charge and discharge control circuit disclosed in the above embodiments have the same or corresponding beneficial effects, and will not be described again here to avoid repetition.

[0074] The embodiment of the present disclosure also provides a mobile terminal, comprising the above-mentioned power supply device.

[0075] The mobile terminal disclosed in the above embodiment and the power supply device disclosed in the above embodiments have the same or corresponding beneficial effects, which will not be described again here to avoid repetition.

[0076] It should be noted that, in this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0077] The above description is only a specific embodiment of the present disclosure, so that those skilled in the art can understand or implement the present disclosure. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present disclosure. Therefore, the present disclosure will not be limited to the embodiments described herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A battery charge and discharge control circuit, characterized in that: include: Current limiting module, voltage control module and control module; The first end of the current limiting module is electrically connected to the positive end of the first battery, the second end of the current limiting module is electrically connected to the positive end of the second battery, the control end of the current limiting module is electrically connected to the output end of the voltage control module, the output end of the control module is electrically connected to the input end of the voltage control module, and the second end of the current limiting module is also electrically connected to the charge and discharge circuit; The current limiting module is used to limit the charging and discharging current of the first battery.

2. The battery charge and discharge control circuit according to claim 1, characterized in that: Also includes a voltage detection module; The first detection end of the voltage detection module is electrically connected to the positive end of the first battery, the second detection end of the voltage detection module is electrically connected to the positive end of the second battery, and the output end of the voltage detection module is electrically connected to the input end of the control module.

3. The battery charge and discharge control circuit according to claim 2, characterized in that: The current limiting module includes: at least one switch unit and a current control unit; The first end of the current control unit is electrically connected to the positive end of the first battery, the second end of the current control unit is electrically connected to the positive end of the second battery, and the second end of the current control unit is also connected to the charge and discharge circuit; the control end of the switch unit is electrically connected to the output end of the voltage control module, the first end of the switch unit is electrically connected to the positive end of the first battery, and the second end of the switch unit is electrically connected to the charge and discharge circuit.

4. The battery charge and discharge control circuit according to claim 3, characterized in that: The current control unit includes a first resistor.

5. The battery charge and discharge control circuit according to claim 3, characterized in that: The switch unit comprises: a first NMOS tube; The gate of the first NMOS tube is electrically connected to the output end of the voltage control module, the first electrode of the first NMOS tube is electrically connected to the positive terminal of the first battery, and the second electrode of the first NMOS tube is electrically connected to the charge and discharge circuit.

6. The battery charge and discharge control circuit according to claim 3, characterized in that: The switch unit includes: a second NMOS tube and a third NMOS tube; The gate of the second NMOS tube is electrically connected to the first output end of the voltage control module, the gate of the third NMOS tube is electrically connected to the second output end of the voltage control module, the source of the second NMOS tube is electrically connected to the positive terminal of the first battery, the drain of the second NMOS tube is electrically connected to the drain of the third NMOS tube, and the source of the third NMOS tube is electrically connected to the charge and discharge circuit.

7. The battery charge and discharge control circuit according to any one of claims 5 to 6, characterized in that: The voltage control module is a boost control circuit.

8. The battery charge and discharge control circuit according to claim 3, characterized in that: The switch unit comprises: a first PMOS tube; The gate of the first PMOS tube is electrically connected to the output end of the voltage control module, the first electrode of the first PMOS tube is electrically connected to the positive terminal of the first battery, and the second electrode of the first PMOS tube is electrically connected to the charge and discharge circuit.

9. A power supply device, characterized in that: The invention comprises a battery charge and discharge control circuit as claimed in any one of claims 1 to 8.

10. A mobile terminal, characterized in that: Comprising the power supply device as claimed in claim 9.

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