A protection circuit for short circuit of a boost output

Abstract

The utility model relates to power management technical field discloses a kind of protection circuit of high reliability and better safety boost output short circuit, including switch control module (101), boost module (102) and short circuit detection module (103), wherein, when external short circuit, the potential of the second signal end of short circuit detection module (103) is pulled low, to control its conduction, short circuit detection module (103) third signal end exports a short circuit signal to the second signal end of switch control module (101), switch control module (101) is controlled to be off, to shut off battery pack output voltage signal.

Description

Technical Field

[0001] This utility model relates to the field of power management technology, and more specifically, to a protection circuit for short circuit of boost output. Background Technology

[0002] Currently, the demand for small-scale photovoltaic energy storage is growing in Africa. With constantly changing user needs, many small-scale energy storage products need to support various electrical devices, with mainstream DC devices typically operating at 12V. The development trend of lithium batteries is towards larger single-cell capacity; a single cell voltage of 3.2V can achieve a capacity of 314Ah. Therefore, the battery pack voltage of many energy storage products cannot reach the operating voltage of DC devices, necessitating the use of boost circuits. Boost chips generally lack short-circuit protection; once a short circuit occurs, the resulting large current will trigger the battery protection chip, leading to a system power outage. A commonly used protection circuit is the self-resetting fuse, but it has several drawbacks for use in small-scale energy storage products in Africa.

[0003] On the one hand, these small energy storage products have very little space, and the heat generated will cause the internal temperature of the entire product to rise, affecting battery use;

[0004] On the other hand, in the event of a short circuit, a resettable fuse is essentially a resistor, and its power consumption can reach several watts. This is unacceptable given that the battery capacity of a small energy storage product is already low. Summary of the Invention

[0005] The technical problem to be solved by this utility model is to provide a high-reliability and safer protection circuit for short circuits in boost output, addressing the defect in the prior art where the heat generated causes the internal temperature of the entire product to rise, affecting battery use.

[0006] The technical solution adopted by this utility model to solve its technical problem is: to construct a protection circuit for short circuit of boost output, which has the following features:

[0007] A switch control module, which is configured within a protection circuit, has a first signal terminal for receiving an enable signal, which is used to control the on / off state of the battery pack output.

[0008] A boost module, whose input terminal is connected to the output terminal of the switch control module, is used to receive the voltage signal output by the battery pack and boost the input voltage signal.

[0009] The short-circuit detection module has its first signal terminal connected to one end of the battery pack, and is used to acquire the voltage signal of the battery pack.

[0010] The second signal terminal of the short-circuit detection module is connected to the output terminal of the boost module, and is used to receive the boosted voltage signal.

[0011] The third signal terminal of the short-circuit detection module is connected to the second signal terminal of the switch control module;

[0012] When an external short circuit occurs, the potential of the second signal terminal of the short circuit detection module is pulled low to control its conduction. The third signal terminal of the short circuit detection module outputs a short circuit signal to the second signal terminal of the switch control module, and the switch control module is controlled to turn off to shut down the output voltage signal of the battery pack.

[0013] In some embodiments, the switch control module includes at least a first transistor and a first MOSFET.

[0014] The base of the first transistor is connected to the enable terminal of the main controller via a first resistor, for receiving the enable signal output by the main controller.

[0015] The base of the first transistor is also connected to the third signal terminal of the short-circuit detection module to receive the short-circuit signal.

[0016] The collector of the first transistor is connected to the gate of the first MOSFET through a second resistor.

[0017] The source of the first MOSFET is connected to the output terminal of the battery pack.

[0018] The drain of the first MOSFET is coupled to the input terminal of the boost module.

[0019] The emitter of the first transistor is connected to the common terminal.

[0020] When the input enable signal is high, the first transistor is controlled to turn on, pulling the gate voltage of the first MOSFET to a low level, thereby controlling the first MOSFET to turn on, and the battery pack outputs the voltage signal to the boost module;

[0021] When the short-circuit detection module outputs the short-circuit signal, the base voltage of the first transistor is pulled to a low level, the first transistor is turned off, and thus the first MOS transistor is turned off.

[0022] In some embodiments, the short-circuit detection module includes at least a second transistor and a third transistor.

[0023] The base of the second transistor is connected to the output terminal of the boost module through the eleventh resistor.

[0024] The emitter of the second transistor is connected to one end of the battery pack.

[0025] The collector of the second transistor is connected to the base of the third transistor through a thirteenth resistor.

[0026] The collector of the third transistor is coupled to the base of the first transistor.

[0027] The emitter of the third transistor is connected to the common terminal.

[0028] In some embodiments, the short-circuit detection module further includes a first diode.

[0029] The anode of the first diode is connected to one end of the battery pack.

[0030] The cathode of the first diode is connected to the emitter of the second transistor.

[0031] In some embodiments, the first transistor and the third transistor are selected as NPN transistors.

[0032] The second transistor is selected as a PNP type transistor.

[0033] The first MOSFET is selected as a P-channel MOSFET.

[0034] In some embodiments, the boost module includes at least a first inductor and a power manager.

[0035] One end of the first inductor and the power input terminal of the power manager are connected to the drain of the first MOSFET.

[0036] The other end of the first inductor is connected to a signal input terminal of the power manager.

[0037] The power manager is used to receive the voltage signal output by the battery pack and to boost the input voltage signal.

[0038] The output terminal of the power manager is connected to the base of the second transistor.

[0039] In some embodiments, the boost module further includes an input filtering module and an output filtering module.

[0040] One end of the input filtering module is connected to the drain of the first MOS transistor.

[0041] The other end of the input filtering module is connected to the common terminal.

[0042] One end of the output filtering module is connected to the output of the power manager.

[0043] The other end of the output filtering module is connected to the common terminal.

[0044] In some embodiments, the input filtering module includes a first capacitor and a second capacitor connected in parallel.

[0045] One end of the first capacitor and one end of the second capacitor are connected to the drain of the first MOSFET.

[0046] The other end of the first capacitor and the second capacitor are connected to a common terminal.

[0047] In some embodiments, the output filtering module includes a seventh capacitor, an eighth capacitor, and a ninth capacitor connected in parallel.

[0048] One end of the seventh capacitor, the eighth capacitor, and the ninth capacitor is connected to the output terminal of the power manager.

[0049] The other ends of the seventh capacitor, the eighth capacitor, and the ninth capacitor are connected to the common terminal.

[0050] The boost output short-circuit protection circuit of this invention includes a switch control module, a boost module, and a short-circuit detection module. When an external short circuit occurs, the potential of the second signal terminal of the short-circuit detection module is pulled low to control its conduction. The third signal terminal of the short-circuit detection module outputs a short-circuit signal to the second signal terminal of the switch control module, which is then controlled to turn off, thereby shutting down the battery pack output voltage signal. Compared with existing technologies, this invention detects the voltage signal at the output terminal of the boost module via the short-circuit detection module. When a short circuit occurs, the voltage at the output terminal of the boost module is pulled down to 0V, triggering the short-circuit detection module to conduct the corresponding output short-circuit signal, thereby controlling the switch control module to turn off. This ensures the safety and reliability of the circuit or battery pack operation. It effectively solves the problem that when a short circuit occurs, the large current generated triggers the battery protection chip, leading to system power loss and inability to recover. Furthermore, in small energy storage products with limited space, heat generation can cause the internal temperature of the entire product to rise, affecting battery performance. Attached Figure Description

[0051] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings:

[0052] Figure 1 This is a circuit diagram of an embodiment of the boost output short-circuit protection circuit provided by this utility model. Detailed Implementation

[0053] To provide a clearer understanding of the technical features, objectives, and effects of this utility model, the specific embodiments of this utility model will now be described in detail with reference to the accompanying drawings.

[0054] like Figure 1 As shown, in the first embodiment of the boost output short-circuit protection circuit of this utility model, the boost output short-circuit protection circuit 100 includes a switch control module 101, a boost module 102, and a short-circuit detection module 103.

[0055] The switch control module 101 is used to receive an enable signal or a short circuit signal. The input enable signal or short circuit signal is used to control the on / off state of the battery pack BAT output voltage signal.

[0056] The boost module 102 is used to receive the voltage signal output by the battery pack BAT when the switch control module 101 is controlled to be turned on, and to boost the input voltage signal to output a DC12V voltage signal.

[0057] The short-circuit detection module 103 is used to acquire the voltage signal output by the boost module 102. When the acquired voltage signal is pulled down to a low level (such as around 0V), the short-circuit detection module 103 is triggered to conduct and outputs a short-circuit signal to the switch control module 101 to control the switch control module 101 to turn off.

[0058] Specifically, the switch control module 101 is configured in the protection circuit, and its first signal terminal is used to receive the enable signal input from the main controller (not shown). The enable signal (high level / low level) is used to control the on / off state of the switch control module 101, and the on / off state of the battery pack BAT output is controlled by controlling the on / off state of the switch control module 101.

[0059] Furthermore, the input terminal of the boost module 102 is connected to the output terminal of the switch control module 101. When the switch control module 101 is turned on, the voltage signal output by the battery pack BAT is input to the boost module 102 through the switch control module 101, and the input voltage signal is boosted to output a DC12V voltage signal.

[0060] Furthermore, the first signal terminal of the short-circuit detection module 103 is connected to one end of the battery pack BAT to obtain the voltage signal of the battery pack BAT and provide a voltage signal (such as 1.5V) for its operation.

[0061] The second signal terminal of the short-circuit detection module 103 is connected to the output terminal of the boost module 102 to receive the boosted voltage signal (corresponding to DC12V).

[0062] The third signal terminal of the short-circuit detection module 103 is connected to the second signal terminal of the switch control module 101;

[0063] When an external short circuit occurs, the potential of the second signal terminal of the short circuit detection module 103 is pulled low, that is, the DC12V voltage output by the boost module 102 is pulled down to 0V, thereby controlling the short circuit detection module 103 to conduct.

[0064] The third signal terminal of the controlled short-circuit detection module 103 can output at least one short-circuit signal. The short-circuit signal is output to the second signal terminal of the switch control module 101, and the switch control module 101 is controlled to turn off, so as to turn off the battery pack BAT output voltage signal.

[0065] Using this technical solution, the voltage signal at the output terminal of the boost module is detected by the short-circuit detection module. When a short circuit occurs, the voltage at the output terminal of the boost module is pulled down to 0V, thereby triggering the short-circuit detection module to conduct the corresponding output short-circuit signal, which controls the switch control module to shut down. This ensures the safety and reliability of the circuit or battery pack operation. It can effectively solve the problem that when a short circuit occurs, the large current generated will trigger the battery protection chip, resulting in a system power outage that cannot be self-recovered. In addition, this type of small energy storage product has a very small space, and the heat generated will cause the internal temperature of the entire product to rise, affecting the use of the battery.

[0066] In some implementations, to ensure the reliability of the battery pack BAT output circuit switching, a first transistor Q101 and a first MOSFET VT101 can be provided in the switch control module 101.

[0067] Among them, the first transistor Q101 is selected as an NPN transistor, and the first MOSFET VT101 is selected as a P-channel MOSFET, both of which have the function of switching;

[0068] Specifically, the base of the first transistor Q101 is connected to the enable terminal (EN) of the main controller (not shown) through the first resistor R101. The enable signal output by the main controller is input to the base of the first transistor Q101 through the first resistor R101.

[0069] The base of the first transistor Q101 is also connected to the third signal terminal of the short-circuit detection module 103, and is used to receive the short-circuit signal output by the short-circuit detection module 103 when it is turned on.

[0070] In this configuration, the collector of the first transistor Q101 is connected to the gate of the first MOSFET VT101 through the second resistor R102.

[0071] The source of the first MOSFET VT101 is connected to the output terminal of the battery pack BAT.

[0072] The output terminal of the battery pack BAT is also connected to the gate of the first MOSFET VT101 through a third resistor R103.

[0073] The drain of the first MOSFET VT101 is coupled to the input terminal of the boost module 102.

[0074] The emitter of the first transistor Q101 is connected to the common terminal.

[0075] When the input enable signal is high, the first transistor Q101 is controlled to conduct, pulling the gate voltage of the first MOSFET VT101 to a low level, thereby controlling the first MOSFET VT101 to conduct. The battery pack BAT outputs a voltage signal to the boost module 102. After the input voltage signal is boosted by the boost module 102, a DC12V voltage is output.

[0076] When a short circuit occurs in the circuit, the DC12V voltage signal output by the boost module 102 is pulled down to 0V to control the short circuit detection module 103 to turn on, and a short circuit signal is output accordingly. The base voltage of the first transistor Q101 is pulled down to a low level, so that the first transistor Q101 is turned off, which in turn controls the first MOSFET VT101 to turn off, and the output of the battery pack BAT is turned off.

[0077] When the circuit recovers, the short circuit detection module 103 switches from being on to being off. The short circuit detection module 103 stops outputting the short circuit signal, and the enable signal continues to act on the base of the first transistor Q101 to control the first transistor Q101 to be on, thereby controlling the first MOSFET VT101 to be on, so that the output circuit of the battery pack BAT switches from being off to being on.

[0078] In some implementations, in order to ensure the reliability of the output short-circuit signal, a second transistor Q102 and a third transistor Q103 can be provided in the short-circuit detection module 103. The second transistor Q102 is selected as a PNP transistor and the third transistor Q103 is selected as an NPN transistor, both of which have the function of switching.

[0079] Specifically, the base of the second transistor Q102 is connected to the output terminal of the boost module 102 through the eleventh resistor R111 to obtain the voltage signal (corresponding to 12V) output by the boost module 102.

[0080] Furthermore, the emitter of the second transistor Q102 is connected to one end of the battery pack BAT to obtain the voltage signal (e.g., 1.5V) output by the battery pack BAT.

[0081] The collector of the second transistor Q102 is connected to the base of the third transistor Q103 through the thirteenth resistor R113.

[0082] The collector of the third transistor Q103 is coupled to the base of the first transistor Q101.

[0083] The emitter of the third transistor Q103 is connected to the common terminal.

[0084] Specifically, when a short circuit occurs, the voltage signal output by the boost module 102 (corresponding to 12V) is pulled down to 0V, the second transistor Q102 is turned on, and the voltage signal output by the battery pack BAT (e.g., 1.5V) is input to the base of the third transistor Q103 through the second transistor Q102 to control the third transistor Q103 to turn on, outputting a short circuit signal to the base of the first transistor Q101, so that the enable signal of the base of the first transistor Q101 is pulled down to a low level to control the first transistor Q101 to turn off, thereby controlling the first MOSFET VT101 to turn off.

[0085] In some embodiments, the short-circuit detection module 103 further includes a first diode D101, wherein the anode of the first diode D101 is connected to one end of the battery pack BAT.

[0086] The cathode of the first diode D101 is connected to the emitter of the second transistor Q102.

[0087] The voltage signal output by the battery pack BAT is input to the emitter of the second transistor Q102 via the first diode D101.

[0088] In some implementations, to meet the power demand of the load, a first inductor L101 and a power manager U101 can be provided in the boost module 102, wherein the first inductor L101 has the function of energy storage, and the power manager U101 has the function of switching and calculation.

[0089] Specifically, one end of the first inductor L101 and the power input terminal (corresponding to pin 12) of the power manager U101 are connected to the drain of the first MOSFET VT101.

[0090] The other end of the first inductor L101 is connected to a signal input terminal (corresponding to pin 7) of the power manager U101.

[0091] The first inductor L101 and the power manager U101 are used to receive the voltage signal output by the battery pack BAT and to boost the input voltage signal.

[0092] The output of power manager U101 is connected to the base of the second transistor Q102;

[0093] The power manager U101 controls the switching of its internal switching transistor. During charging, the switching transistor inside the power manager U101 is turned on, and the first inductor L101 absorbs energy.

[0094] During discharge, the switching transistor inside the power manager U101 is turned off, and the first inductor L101 releases energy.

[0095] In some embodiments, the boost module 102 further includes an input filtering module and an output filtering module.

[0096] One end of the input filtering module is connected to the drain of the first MOSFET VT101, which is used to filter the voltage signal input to the battery pack BAT.

[0097] The other end of the input filtering module is connected to the common terminal.

[0098] One end of the output filtering module is connected to the output terminal of the power manager U101, and it is used to filter the voltage signal (corresponding to DC12V) output by the power manager U101.

[0099] The other end of the output filter module is connected to the common terminal.

[0100] In some implementations, the input filtering module includes a first capacitor C101 and a second capacitor C102 connected in parallel.

[0101] In this configuration, one end of the first capacitor C101 and the second capacitor C102 are connected to the drain of the first MOSFET VT101.

[0102] The other ends of the first capacitor C101 and the second capacitor C102 are connected to the common terminal.

[0103] In some implementations, the output filtering module includes a seventh capacitor C107, an eighth capacitor C108, and a ninth capacitor C109 connected in parallel.

[0104] One end of the seventh capacitor C107, the eighth capacitor C108, and the ninth capacitor C109 is connected to the output terminal of the power manager U101.

[0105] The other ends of the seventh capacitor C107, the eighth capacitor C108, and the ninth capacitor C109 are connected to the common terminal.

[0106] Specifically, when an external short circuit occurs, the DC12V output of the power manager U101 is pulled down to 0V. The voltage drop across the eleventh resistor R111 reaches the conduction threshold of the second transistor Q102, turning on the second transistor Q102. The voltage output from the battery pack BAT passes through the first diode D101, the second transistor Q102, and the thirteenth resistor R113 to the base of the third transistor Q103. The third transistor Q103 turns on, pulling down the short-circuit signal (SHORT). The short-circuit signal (SHORT) is then sent to the base of the first transistor Q101. The enable signal of the base of the first transistor Q101 is pulled down by the short-circuit signal (SHORT), causing the first transistor Q101 to be turned off. At the same time, the first MOSFET VT101 is also turned off, cutting off the input voltage of the power manager U101 and turning off the DC12V output, thus providing short-circuit protection with extremely low power consumption.

[0107] When the short circuit is removed, the second transistor Q102 changes from being on to being off, and at the same time the third transistor Q103 is off. The short circuit signal (SHORT) at the base of the first transistor Q101 is pulled high by the enable signal, and the first transistor Q101 turns on. The first MOSFET VT101 turns on, and the power manager U101 works normally, outputting a DC12V voltage.

[0108] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

Claims

1. A protection circuit for short circuit in boost output, characterized in that, have: A switch control module, which is configured within a protection circuit, has a first signal terminal for receiving an enable signal, which is used to control the on / off state of the battery pack output. A boost module, whose input terminal is connected to the output terminal of the switch control module, is used to receive the voltage signal output by the battery pack and boost the input voltage signal. The short-circuit detection module has its first signal terminal connected to one end of the battery pack, and is used to acquire the voltage signal of the battery pack. The second signal terminal of the short-circuit detection module is connected to the output terminal of the boost module, and is used to receive the boosted voltage signal. The third signal terminal of the short-circuit detection module is connected to the second signal terminal of the switch control module; When an external short circuit occurs, the potential of the second signal terminal of the short circuit detection module is pulled low to control its conduction. The third signal terminal of the short circuit detection module outputs a short circuit signal to the second signal terminal of the switch control module, and the switch control module is controlled to turn off to shut down the output voltage signal of the battery pack.

2. The protection circuit for short circuit of boost output according to claim 1, characterized in that, The switch control module includes at least a first transistor and a first MOSFET. The base of the first transistor is connected to the enable terminal of the main controller via a first resistor, for receiving the enable signal output by the main controller. The base of the first transistor is also connected to the third signal terminal of the short-circuit detection module to receive the short-circuit signal. The collector of the first transistor is connected to the gate of the first MOSFET through a second resistor. The source of the first MOSFET is connected to the output terminal of the battery pack. The drain of the first MOSFET is coupled to the input terminal of the boost module. The emitter of the first transistor is connected to the common terminal. When the input enable signal is high, the first transistor is controlled to turn on, pulling the gate voltage of the first MOSFET to a low level, thereby controlling the first MOSFET to turn on, and the battery pack outputs the voltage signal to the boost module; When the short-circuit detection module outputs the short-circuit signal, the base voltage of the first transistor is pulled to a low level, the first transistor is turned off, and thus the first MOS transistor is turned off.

3. The protection circuit for short circuit of boost output according to claim 2, characterized in that, The short-circuit detection module includes at least a second transistor and a third transistor. The base of the second transistor is connected to the output terminal of the boost module through the eleventh resistor. The emitter of the second transistor is connected to one end of the battery pack. The collector of the second transistor is connected to the base of the third transistor through a thirteenth resistor. The collector of the third transistor is coupled to the base of the first transistor. The emitter of the third transistor is connected to the common terminal.

4. The protection circuit for short circuit of boost output according to claim 3, characterized in that, The short-circuit detection module also includes a first diode. The anode of the first diode is connected to one end of the battery pack. The cathode of the first diode is connected to the emitter of the second transistor.

5. The protection circuit for short circuit of boost output according to claim 3, characterized in that, The first transistor and the third transistor are selected as NPN type transistors. The second transistor is selected as a PNP type transistor. The first MOSFET is selected as a P-channel MOSFET.

6. The protection circuit for short circuit of boost output according to claim 3, characterized in that, The boost module includes at least a first inductor and a power manager. One end of the first inductor and the power input terminal of the power manager are connected to the drain of the first MOSFET. The other end of the first inductor is connected to a signal input terminal of the power manager. The power manager is used to receive the voltage signal output by the battery pack and to boost the input voltage signal. The output terminal of the power manager is connected to the base of the second transistor.

7. The protection circuit for short circuit of boost output according to claim 6, characterized in that, The boost module also includes an input filtering module and an output filtering module. One end of the input filtering module is connected to the drain of the first MOS transistor. The other end of the input filtering module is connected to the common terminal. One end of the output filtering module is connected to the output of the power manager. The other end of the output filtering module is connected to the common terminal.

8. The protection circuit for short circuit of boost output according to claim 7, characterized in that, The input filtering module includes a first capacitor and a second capacitor connected in parallel. One end of the first capacitor and one end of the second capacitor are connected to the drain of the first MOSFET. The other end of the first capacitor and the second capacitor are connected to a common terminal.

9. The protection circuit for short circuit of boost output according to claim 7, characterized in that, The output filtering module includes a seventh capacitor, an eighth capacitor, and a ninth capacitor connected in parallel. One end of the seventh capacitor, the eighth capacitor, and the ninth capacitor is connected to the output terminal of the power manager. The other ends of the seventh capacitor, the eighth capacitor, and the ninth capacitor are connected to the common terminal.

Images