Lithium battery over-current alarm and fast recovery circuit

Abstract

The utility model relates to a lithium battery over-current alarm and fast recovery circuit which comprises a single-chip microcomputer circuit module, a switch control circuit module and a charging management circuit module. The single-chip microcomputer circuit module comprises voltage detection and load control and is used for detecting the voltage state of a battery to control operation or stop of equipment. The charging management circuit module comprises a charging management chip U4 and a lithium battery BT1 and is used for charging the lithium battery BT1; and the switch control circuit module comprises a PmosQ4 and a triode Q5, and is used for recovering the lithium battery BT1 to the working voltage when being loaded. The voltage of the lithium battery after overcurrent is detected through the single-chip microcomputer, the single-chip microcomputer performs early warning and cuts off the load to protect the safety of the circuit, and then the switch circuit composed of the PMOS and the triode makes up the defect that the lithium battery can be restarted only after the load needs to be thoroughly cut off after overcurrent through the restart switch, so that the lithium battery with low discharge capacity is suitable for more high-load scenes, and the service life of the lithium battery is prolonged. The circuit is effectively protected and the cost is reduced.

Description

TECHNICAL FIELD

[0001] The utility model belongs to lithium battery overcurrent technical field, concretely relates to a lithium battery overcurrent alarm and fast recovery circuit. BACKGROUND

[0002] With the gradual popularization of automation, AI and the continuous development of intelligentization in the medical industry, there are more and more lithium battery related products, handheld medical devices are more and more popular, and lithium batteries are more and more widely used due to their large energy density, superior cycle performance, fast charging and discharging and other excellent characteristics, but due to their characteristics, there are strict requirements on the use method and scene. At the same time, due to the production cost, the low-priced lithium battery is not equipped with a self-starting circuit; therefore, the device using the low-priced lithium battery scheme cannot start in extreme conditions, affecting the customer experience. In view of this, it is necessary to provide a circuit that can quickly recover after lithium battery overcurrent to overcome the above-mentioned defects.

[0003] In summary, the prior art has the problem that low-priced lithium batteries are not equipped with a self-starting circuit, which causes the device to be unable to start in extreme conditions, affecting the customer experience. SUMMARY

[0004] The purpose of this section is to outline some aspects of the embodiments of the present utility model and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the abstract of the specification and the utility model name to avoid obscuring the purpose of this section, the abstract of the specification and the utility model name, and such simplifications or omissions cannot be used to limit the scope of the present utility model.

[0005] Therefore, the purpose of the present utility model is to provide a lithium battery overcurrent alarm and fast recovery circuit, which can solve the problem that the prior art has low-priced lithium batteries that are not equipped with a self-starting circuit, which causes the device to be unable to start in extreme conditions, affecting the customer experience. The present utility model provides a lithium battery overcurrent alarm and fast recovery circuit, which comprises a single-chip microcomputer circuit module, a switch control circuit module and a charge management circuit module; the single-chip microcomputer circuit module comprises voltage detection and load control, which is used to detect the voltage state of the battery to control the operation or stop of the device; the charge management circuit module comprises a charge management chip U4 and a lithium battery BT1, which is used to charge the lithium battery BT1; the switch control circuit module comprises a Pmos Q4 and a triode Q5, which is used to restore the lithium battery BT1 to the working voltage when the load is connected.

[0006] Optionally, the voltage detection comprises an MCU control circuit single U2, a voltage dividing resistor R5, a voltage dividing resistor R6, a voltage detection network BT+ and a network Bat V Det; the load control comprises an Nmos Q1, an Nmos Q2, a Ctrl network and a network Gate.

[0007] Optionally, the network Gate and the Nmos Q1, the Nmos Q2 are connected, the Ctrl network, the voltage detection network BT+ and the network Bat V Det are connected with MCU control circuit single-chip U2.

[0008] Optionally, the MCU control circuit single-chip U2 is connected with the alarm signal network Charge.

[0009] Optionally, the alarm signal network Charge is connected with the LED or the buzzer.

[0010] In summary, the utility model includes at least one of the following beneficial effects:

[0011] The utility model discloses a lithium battery overcurrent alarm and rapid recovery circuit, including the lithium battery, the load, the overcurrent detection circuit, the alarm signal network, the MCU control circuit, the switch control circuit, the charge management circuit, the overcurrent detection circuit is connected with the lithium battery, the alarm signal network is connected with the MCU control circuit, the switch control circuit is connected with the MCU control circuit, the charge management circuit is connected with the MCU control circuit, the load is connected with the switch control circuit. BRIEF DESCRIPTION OF DRAWINGS

[0012] In order to more clearly illustrate the technical scheme in the embodiment of the utility model or prior art, below will to the embodiment or prior art description needed to use the drawing briefly introduce, obviously, below description's drawing only some embodiments of the utility model, for the ordinary skilled person in the art comes, under the premise of not paying the creative labor, can also obtain other drawings according to these drawings.

[0013] Figure 1 It is the whole circuit diagram of a lithium battery overcurrent alarm and rapid recovery circuit of the utility model;

[0014] Figure 2 It is the charge management circuit module schematic drawing of a lithium battery overcurrent alarm and rapid recovery circuit of the utility model;

[0015] Figure 3 It is the switch control circuit module schematic drawing of a lithium battery overcurrent alarm and rapid recovery circuit of the utility model;

[0016] Figure 4 It is the MCU control circuit module schematic drawing of a lithium battery overcurrent alarm and rapid recovery circuit of the utility model;

[0017] Figure 5 It is the existing battery circuit diagram. IMPLEMENTATION

[0018] Below, combining the drawings of the utility model Figures 1-5The utility model further illustrates in detail.

[0019] Embodiment one, refer to Figures 1-5 , in order to be able to solve the prior art low price lithium battery is not equipped with self starting circuit in extreme case and cannot start the problem of affecting customer experience. The utility model discloses a lithium battery overcurrent alarm and quick recovery circuit, including, single-chip microcomputer circuit module, switch control circuit module and charge management circuit module, single-chip microcomputer circuit module includes voltage detection and load control, for detecting the voltage state of battery to control the operation or stop of equipment, charge management circuit module includes charge management chip U4 and lithium battery BT1, for charging lithium battery BT1, switch control circuit module includes Pmos Q4 and triode Q5, for allowing lithium battery BT1 to recover to working voltage when load. Voltage detection includes MCU control circuit single-chip U2, voltage dividing resistor R5, voltage dividing resistor R6, voltage detection network BT+ and network Bat V Det, load control includes Nmos Q1, Nmos Q2, Ctrl network and network Gate, network Gate is connected with Nmos Q1 and Nmos Q2, and Ctrl network, voltage detection network BT+ and network Bat V Det are connected with MCU control circuit single-chip U2. MCU control circuit single-chip U2 is connected with alarm signal network Charge. Alarm signal network Charge is connected with LED or buzzer.

[0020] Single-chip microcomputer circuit detects the voltage state of lithium battery to control the operation or stop of equipment, charge management circuit controls charging current and voltage when charging, charges lithium battery, and charge management chip stops outputting current to lithium battery by detecting the threshold value of voltage after lithium battery is fully charged, switch control circuit is when equipment operation encounters unexpected situation and makes lithium battery overcurrent and cannot actively recover power supply, through switch circuit control, makes lithium battery and load all disconnect, thereby making lithium battery recover to working voltage.

[0021] Charge management circuit supplies power to equipment, and single-chip microcomputer circuit monitors and controls the operation of equipment, and when equipment operation appears abnormal, single-chip microcomputer controls the operation or stop of equipment, but because lithium battery is connected with load and cannot recover to working voltage automatically, so it is necessary to make lithium battery completely disconnect with peripheral load through switch control circuit, to make lithium battery recover to working voltage.

[0022] The utility model detects the voltage value of lithium battery after overdischarge through single-chip microcomputer, and single-chip microcomputer disconnects load GND through MOS and alarms, at this time, lithium battery is in overcurrent protection state and cannot work, and switch circuit controls MOS and triode to make lithium battery restart quickly.

[0023] Specific implementation principle: when the load at J2 occurs current overload exceeding the lithium battery carrying capacity, the abnormal voltage will be transmitted to the MCU control circuit single chip U2 through the voltage detection network BT+ network through the voltage dividing resistor R5 and the voltage dividing resistor R6, at this time, the MCU control circuit single chip U2 compares the detected signal with the threshold value set by the program to determine whether it is abnormal. If it is abnormal, the load of J2 will be stopped by controlling the turn-off of Nmos Q1 and Nmos Q1 through the Ctrl network through the resistor R3, and the MCU control circuit single chip U2 sends an alarm signal through the alarm signal network Charge, which can be connected with LED or buzzer.

[0024] At this time, the lithium battery BT1 is in an overcurrent protection state, and cannot recover to the starting voltage of the device without taking out the lithium battery. If the utility model is not used, the switch S1 of the switch control circuit alone cannot make the device work normally. Because the voltage of the lithium battery is always below the working voltage of the device.

[0025] Therefore, the utility model uses the switch S1 of the switch control circuit to disconnect the voltage at the load, so that the base voltage of the N-type triode Q5 controlled by the resistor R2 at the original place is low, then the collector and emitter of the triode Q5 are disconnected, which further affects the gate of the Pmos Q4S, so that the source and drain of the Pmos Q4 are disconnected, and then the BT network and the voltage detection network BT+ connected with the lithium battery BT1 are completely disconnected with the load J2 and the charge management chip U4 and the MCU control circuit single chip U2. In this way, the lithium battery can be restarted.

[0026] At this time, the switch S1 of the switch control circuit is closed again, and the lithium battery power supply is restored to normal, and the device is restarted normally.

[0027] The above are preferred embodiments of the utility model, which do not limit the protection scope of the utility model, so that: all equivalent changes made according to the structure, shape and principle of the utility model should be covered in the protection scope of the utility model.

Claims

1. A lithium battery overcurrent alarm and fast recovery circuit, characterized in that, It includes single-chip computer circuit module, switch control circuit module and charge management circuit module; the single-chip computer circuit module includes voltage detection and load control, for detecting the voltage state of battery to control the running or stopping of equipment;The charge management circuit module includes charge management chip U4 and lithium battery BT1, for charging lithium battery BT1;The switch control circuit module includes Pmos Q4 and triode Q5, for restoring lithium battery BT1 to working voltage when load.

2. The overcurrent alarm and fast recovery circuit for lithium battery according to claim 1, characterized in that, The voltage detection includes MCU control circuit single-chip U2, voltage dividing resistor R5, voltage dividing resistor R6, voltage detection network BT+ and network Bat VDet;The load control includes Nmos Q1, Nmos Q2, Ctrl network and network Gate.

3. The overcurrent alarm and fast recovery circuit for lithium batteries according to claim 2, characterized in that, The network Gate is connected with the Nmos Q1 and the Nmos Q2, and the Ctrl network, the voltage detection network BT+ and the network Bat VDet are connected with the MCU control circuit single-chip U2.

4. The overcurrent alarm and fast recovery circuit for lithium batteries of claim 2, wherein, The MCU control circuit single-chip U2 is connected with alarm signal network Charge.

5. The overcurrent alarm and fast recovery circuit for lithium batteries of claim 4, wherein, The alarm signal network Charge is connected with LED or buzzer.

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