Power-off isolation circuit and mobile power supply leasing system

Abstract

The utility model relates to the technical field of mobile power supplies, in particular to a power-off isolation circuit and a mobile power supply leasing system. The base electrode of the first triode and the base electrode of the second triode are both connected with the power supply end of the mobile power supply leasing system, and the collector electrode of the first triode and the emitter electrode of the second triode are both connected with the main control end of the mobile power supply leasing system. The emitter electrode of the first triode and the collector electrode of the second triode are connected with an external interface of the mobile power supply leasing system. A power-off isolation circuit carrying two triodes is designed between a main control end and an external interface of the mobile power supply leasing system, when the mobile power supply leasing system is in a power-off state, the first triode and the second triode are both cut off, the main control end of the mobile power supply leasing system is disconnected from the external interface, and the external interface is disconnected from the main control end. According to the scheme, protection isolation is achieved, and the circuit is simple and low in cost.

Description

Technical Field

[0001] The utility model relates to the technical field of mobile power supplies, in particular to a power-off isolation circuit and a mobile power supply rental system. Background Art

[0002] With the development of shared mobile power rental systems, contact communication through POGO PIN has become the mainstream communication method between devices. However, when the shared mobile power rental system is powered off and separated from the shared mobile power, or when the shared mobile power rental system remains connected to the shared mobile power but the power is disconnected, the communication line between the external interface of the shared mobile power rental system and the main control MCU is still electrically connected and easily affected by external environmental factors, thereby affecting the normal operation of the main control MCU or causing damage to the main control MCU.

[0003] Therefore, it is very important for those skilled in the art to design a power-off isolation circuit and a mobile power rental system that can cut off the communication line of the main control MCU from the external interface exposed to the outside when the main control MCU is powered off. Utility Model Content

[0004] The technical problem to be solved by the embodiments of the utility model is to provide a power-off isolation circuit and a mobile power rental system to solve the problem in the prior art that when the power is disconnected, the external communication interface exposed to the outside and the communication line inside the main control MCU are still in an electrically connected state, and the MCU is easily affected by external environmental factors.

[0005] The utility model discloses a power-off isolation circuit, which is used in a mobile power rental system. The circuit comprises: a first transistor and a second transistor, wherein the base of the first transistor and the base of the second transistor are both connected to the power supply end of the mobile power rental system, the collector of the first transistor and the emitter of the second transistor are both connected to the main control end of the mobile power rental system, and the emitter of the first transistor and the collector of the second transistor are both connected to the external interface of the mobile power rental system.

[0006] Optionally, it also includes a first pull-up resistor and a second pull-up resistor, one end of the first pull-up resistor is connected to the power supply end of the mobile power rental system, and the other end of the first pull-up resistor is connected to the base of the first transistor; one end of the second pull-up resistor is connected to the power supply end of the mobile power rental system, and the other end of the second pull-up resistor is connected to the base of the second transistor.

[0007] The utility model also provides a mobile power rental system, which includes at least one power-off isolation circuit as described above, and also includes a main control circuit and an output circuit. The output circuit includes multiple external interfaces, and the number of the power-off isolation circuits is the same as the number of external interface pairs in the output circuit.

[0008] Optionally, the main control circuit includes a main control chip, and the plurality of power-off isolation circuits are respectively connected to different communication pins of the main control chip.

[0009] Optionally, a protection resistor is provided between the power-off isolation circuit and a communication pin of the main control chip.

[0010] Optionally, a power supply circuit is further included, the power supply circuit includes an external interface power supply end and a system power supply end, the external interface power supply end is connected to the output circuit, and the system power supply end is connected to the power-off isolation circuit.

[0011] Optionally, the power supply circuit further includes a filter module, and the filter module is connected to the system power supply end.

[0012] Optionally, a sampling circuit is further included, the sampling circuit includes a plurality of sampling modules, each of the external interfaces is provided with a sampling terminal, and each of the sampling modules is correspondingly connected to one of the sampling terminals.

[0013] Optionally, the sampling module includes a first sampling resistor and a second sampling resistor, and the first sampling resistor and the second sampling resistor are connected in series.

[0014] Optionally, an indicator light circuit is further included, and the indicator light circuit includes a light emitting diode, and the light emitting diode is connected to the main control chip.

[0015] Compared with the prior art, the beneficial effect of the power-off isolation circuit provided by the embodiment of the utility model is that: by designing a power-off isolation circuit equipped with two transistors between the main control end and the external interface of the mobile power rental system, when the mobile power rental system is powered off, the first transistor and the second transistor are both cut off, thereby disconnecting the connection between the main control end and the external interface of the mobile power rental system, thereby protecting the main control end from being affected by the external connection. This solution not only realizes the function of protection isolation, but also has a simple circuit and low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The technical solution of the utility model will be further described in detail below with reference to the accompanying drawings and embodiments, in which:

[0017] Figure 1 The circuit of the power-off isolation circuit provided by the embodiment of the utility model Figure 1 ;

[0018] Figure 2 The circuit of the power-off isolation circuit provided by the embodiment of the utility model Figure 2 ;

[0019] Figure 3 It is a schematic diagram of a mobile power rental system provided by an embodiment of the utility model;

[0020] Figure 4 is a circuit diagram of an output circuit provided by an embodiment of the utility model;

[0021] Figure 5 It is a circuit diagram of a main control circuit provided by an embodiment of the utility model;

[0022] Figure 6 is a circuit diagram of a power supply circuit provided by an embodiment of the utility model;

[0023] Figure 7 is a circuit diagram of a sampling circuit provided by an embodiment of the utility model;

[0024] Figure 8 It is a circuit diagram of an indicator light circuit provided by an embodiment of the utility model. DETAILED DESCRIPTION

[0025] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. Now, in conjunction with the accompanying drawings, a preferred embodiment of the present utility model is described in detail.

[0026] like Figure 1 to Figure 2 As shown, the utility model provides a specific embodiment of a power-off isolation circuit.

[0027] A power-off isolation circuit for use in a mobile power rental system, referring to Figure 1 The power-off isolation circuit includes: a first transistor N1 and a second transistor N2, a base b of the first transistor N1 and a base b of the second transistor N2 are both connected to the power supply end of the mobile power rental system, a collector c of the first transistor N1 and an emitter e of the second transistor N2 are both connected to the main control end of the mobile power rental system, and an emitter e of the first transistor N1 and a collector c of the second transistor N2 are both connected to the external interface of the mobile power rental system.

[0028] Specifically, refer to Figure 1The first transistor N1 and the second transistor N2 are both NPN transistors, and both can use 3904 transistors. The base of the first transistor N1 and the base of the second transistor N2 are both connected to the power supply end of the mobile rental system to obtain the working voltage. The collector c of the first transistor N1 is connected to the main control end of the mobile power rental system, the emitter e of the first transistor N1 is connected to the external interface of the mobile power supply, the emitter e of the second transistor N2 is connected to the main control end of the mobile power rental system, and the collector c of the second transistor N2 is connected to the external interface of the mobile power supply; when the device is normally powered on, the first transistor N1 and the second transistor N2 are both turned on, and the mobile power rental device works normally. When the device is powered off, the first transistor N1 and the second transistor N2 are both turned off, so that the connection between the main control end of the mobile power rental device and the external interface is disconnected, thereby protecting the main control end of the mobile power rental device from being affected by the external interface.

[0029] Furthermore, the power-off isolation circuit also includes a first pull-up resistor and a second pull-up resistor, one end of the first pull-up resistor is connected to the power supply end of the mobile power rental system, and the other end of the first pull-up resistor is connected to the gate of the first transistor; one end of the second pull-up resistor is connected to the power supply end of the mobile power rental system, and the other end of the second pull-up resistor is connected to the gate of the second transistor.

[0030] Specifically, refer to Figure 2 , the first pull-up resistor R1 and the second pull-up resistor R2 have the same resistance value; one end of the first pull-up resistor R1 is connected to the power supply end of the mobile power rental system to obtain the working voltage, and the other end of the first pull-up resistor R1 is connected to the base of the first transistor N1. When the device is powered on normally, the first pull-up resistor R1 will turn on the first transistor N1. When the device is powered off, the first pull-up resistor R1 fails and the first transistor N1 is cut off; one end of the second pull-up resistor R2 is connected to the power supply end of the mobile power supply to obtain the working voltage, and the other end of the second pull-up resistor R2 is connected to the base of the second transistor N2. When the device is powered on normally, the second pull-up resistor R2 will turn on the second transistor N2. When the device is powered off, the first pull-up resistor R1 fails and the first transistor N1 is cut off.

[0031] When the device is powered on normally, the first pull-up resistor R1 will turn on the first transistor N1, and the second pull-up resistor R2 will turn on the second transistor N2. The signal of the mobile power main control end can be connected to the external interface through the first transistor N1 and the second transistor N2, so as to communicate with other external devices; when the device is powered off, the first pull-up resistor R1 and the second pull-up resistor R2 are both invalid, the first transistor N1 and the second transistor N2 are both cut off, and the mobile power main control end is disconnected from the external interface, so as not to be affected by the external connection.

[0032] With the development of shared mobile power rental equipment, contact communication through POGO PIN has become the mainstream communication method between devices. However, when the shared mobile power rental equipment is powered off and separated from the shared mobile power, or when the shared mobile power rental equipment remains connected to the shared mobile power but the power is disconnected, the external interface of the shared mobile power rental equipment is exposed to the external communication line with the main MCU. It is easily affected by external environmental factors, which will affect the normal operation of the main MCU and even cause damage to the main MCU in severe cases.

[0033] In this embodiment, a power-off isolation circuit equipped with two transistors and two pull-up resistors is designed between the main control end and the external interface. When the mobile power rental device is powered off, the first pull-up resistor and the second pull-up resistor will both fail, so that the first transistor and the second transistor will both be cut off, thereby disconnecting the connection between the main control end of the mobile power rental device and the external interface, thereby protecting the main control end of the mobile power rental device from being affected by the external connection. This solution not only realizes the function of protection isolation, but also has a simple circuit and low cost.

[0034] like Figures 3 to 8 As shown, the utility model also provides a specific embodiment of a mobile power system.

[0035] A mobile power system, reference Figures 1 to 3 The mobile power system includes at least one power-off isolation circuit 10 as described above, and also includes a main control circuit 20 and an output circuit 30. The emitter e of the first transistor N1 and the collector c of the second transistor N2 are both connected to the output circuit 30, and the collector c of the first transistor N1 and the emitter e of the second transistor N2 are both connected to the main control circuit 20.

[0036] Specifically, refer to Figure 1 and Figure 2The main control circuit 20 is mainly used for the control and data processing of the mobile power rental system. The output end of the main control circuit 20 is connected to the input end of the power-off isolation circuit 10, and the output end of the power-off isolation circuit 10 is connected to the input end of the output circuit 30. When the device is powered on normally, the first pull-up resistor R1 in the power-off isolation circuit 10 will turn on the first transistor N1 in the power-off isolation circuit 10, and the second pull-up resistor R2 in the power-off isolation circuit 10 will turn on the second transistor N2 in the power-off isolation circuit 10. The signal of the main control circuit 20 can be transmitted through the power-off isolation circuit 1 0 and the second transistor N2 in the power-off isolation circuit 10 remain connected to the output circuit 30, so as to communicate with other external devices; when the device is powered off, the first pull-up resistor R1 in the power-off isolation circuit 10 and the second pull-up resistor R2 in the power-off isolation circuit 10 are both invalid, the first transistor N1 in the power-off isolation circuit 10 and the second transistor N2 in the power-off isolation circuit 10 are both cut off, and the main control circuit 20 is disconnected from the output circuit 30. Even if the output circuit 30 is exposed to the external environment, the external factors will not affect the main control circuit 20.

[0037] When the mobile power rental device is powered off and separated from the mobile power supply, or when the mobile power rental device remains connected to the mobile power supply but the power supply is disconnected, the external interface of the mobile power rental device exposed to the outside and the communication line inside the main control MCU are still in an electrically connected state, which is easily affected by external environmental factors, which will affect the normal operation of the main control MCU and even cause damage to the main control MCU in severe cases.

[0038] In this embodiment, by designing a mobile power rental system with a main control circuit, an output circuit and a power-off isolation circuit, when the mobile power rental system is powered off, the first pull-up resistor in the power-off isolation circuit and the second pull-up resistor in the power-off isolation circuit will both fail, so that the first transistor in the power-off isolation circuit and the second transistor in the power-off isolation circuit are both cut off, thereby disconnecting the main control circuit from the output circuit, thereby protecting the main control circuit from external influences. This solution not only realizes the function of protection isolation, but also has a simple circuit and low cost.

[0039] In one embodiment, reference Figure 4 The output circuit 30 includes multiple pairs of external interfaces, and the number of power-off isolation circuits is the same as the number of external interface pairs in the output circuit 30.

[0040] Specifically, refer to Figure 3The output circuit 30 includes a POGO PIN1 interface, a POGO PIN2 interface, a POGO PIN3 interface and a POGO PIN4 interface; the POGO PIN1 interface is provided with a POGO-UART-1 pin, the POGO PIN2 interface is provided with a POGO-UART-2 pin, the POGO PIN3 interface is provided with a POGO-UART-3 pin, and the POGO PIN4 interface is provided with a POGO-UART-4 pin. The number of power-off isolation circuits is the same as the number of external interface pairs in the output circuit 30, that is, the POGO-UART-1 pin, the POGO-UART-2 pin, the POGO-UART-3 pin and the POGO-UART-4 pin are all connected to the power-off isolation circuit.

[0041] By setting the number of power-off isolation circuits to be the same as the number of external interface pairs in the output circuit 30, a power-off isolation circuit is set between each external interface and the main control circuit 20. This can ensure that when the mobile power rental system is powered off, the main control circuit 20 can be disconnected from all external interfaces of the output circuit 30 to ensure that the main control circuit 20 is not affected by the external environment.

[0042] In one embodiment, reference Figure 5 The main control circuit 20 includes a main control chip U3, and a plurality of power-off isolation circuits are respectively connected to different communication pins of the main control chip U3.

[0043] Specifically, refer to Figure 5 The main control chip U3 includes multiple communication pins for connecting to the power-off isolation circuit, specifically including UART-1 pin, UART-2 pin, UART-3 pin and UART-4 pin, wherein the UART-1 pin of the main control chip U3 is connected to the POGO-UART-1 pin of the output circuit 30 through a power-off isolation circuit, the UART-2 pin of the main control chip U3 is connected to the POGO-UART-2 pin of the output circuit 30 through a power-off isolation circuit, the UART-3 pin of the main control chip U3 is connected to the POGO-UART-3 pin of the output circuit 30 through a power-off isolation circuit, and the UART-4 pin of the main control chip U3 is connected to the POGO-UART-4 pin of the output circuit 30 through a power-off isolation circuit.

[0044] When the mobile power rental system is powered off, the first transistor N1 and the second transistor N2 in the multiple power-off isolation circuits are both cut off, thereby disconnecting the UART-1 pin of the main control chip U3 from the POGO-UART-1 pin of the output circuit 30, and disconnecting the UART-2 pin of the main control chip U3 from the POGO-UART-2 pin of the output circuit 30, and disconnecting the UART-3 pin of the main control chip U3 from the POGO-UART-3 pin of the output circuit 30, and disconnecting the UART-4 pin of the main control chip U3 from the POGO-UART-4 pin of the output circuit 30.

[0045] In one embodiment, reference Figure 5 A protective resistor is provided between the power-off isolation circuit and the communication pin of the main control chip U3.

[0046] Specifically, the protection resistor is mainly used for current limiting to prevent large current from damaging electronic components of the power-off isolation circuit.

[0047] In one embodiment, reference Figure 6 The mobile power rental system also includes a power supply circuit 40, which includes an external interface power supply end and a system power supply end. The external interface power supply end is connected to the output circuit 30, and the system power supply end is connected to the power-off isolation circuit.

[0048] Specifically, refer to Figure 6 The power supply circuit 40 is mainly used to provide working voltage for other circuits. The power supply circuit 40 is connected to the output circuit 30 through the external interface power supply terminal to provide POGO_5V voltage to the external mobile power supply; the power supply circuit 40 is connected to the power-off isolation circuit through the system power supply terminal, and provides a 3.3V working voltage for the power-off isolation circuit. The power supply circuit 40 can also provide working voltage for other circuits through the system power supply terminal, such as the main control circuit 20.

[0049] In one embodiment, reference Figure 6 The power supply circuit 40 also includes a filter module, and the filter module is connected to the system power supply end.

[0050] Specifically, refer to Figure 5 The filtering module includes multiple parallel filter capacitors, specifically including filter capacitor C1, filter capacitor C2, filter capacitor C3, filter capacitor C4, filter capacitor C5, filter capacitor C6, filter capacitor C7 and filter capacitor C8. Filter capacitor C1, filter capacitor C2, filter capacitor C3, filter capacitor C4, filter capacitor C5, filter capacitor C6, filter capacitor C7 and filter capacitor C8 are all connected in parallel to filter the output current of the power supply circuit to output a stable current to the system power supply end and power other modules in the system.

[0051] In one embodiment, reference Figure 7 The mobile power rental system also includes a sampling circuit 50, which includes a plurality of sampling modules. A sampling terminal is provided on each external interface, and each sampling module is correspondingly connected to a sampling terminal.

[0052] Specifically, refer to Figure 7 The sampling circuit 50 is mainly used for voltage adoption, and includes a first sampling module 51, a second sampling module 52, a third sampling module 53 and a fourth sampling module 54, and each sampling module includes two resistors connected in series; and a first sampling terminal POGO_ADC_1 is provided on the POGO PIN1 interface of the output circuit 30, a first sampling terminal POGO_ADC_2 is provided on the POGO PIN2 interface of the output circuit 30, a first sampling terminal POGO_ADC_3 is provided on the POGO PIN3 interface of the output circuit 30, and a first sampling terminal POGO_ADC_4 is provided on the POGO PIN4 interface of the output circuit 30.

[0053] Further, refer to Figure 7 The first sampling module 51 includes a resistor R41 and a resistor R42, one end of the resistor R41 is connected to the first sampling terminal POGO_ADC_1, the other end of the resistor R41 is connected to one end of the resistor R42, and the other end of the resistor R42 is grounded; the second sampling module 52 includes a resistor R45 and a resistor R58, one end of the resistor R45 is connected to the second sampling terminal POGO_ADC_2, the other end of the resistor R45 is connected to one end of the resistor R58, and the other end of the resistor R58 is grounded; the third sampling module 53 includes a resistor R59 and a resistor R60, one end of the resistor R59 is connected to the third sampling terminal POGO_ADC_3, the other end of the resistor R59 is connected to one end of the resistor R60, and the other end of the resistor R60 is grounded; the fourth sampling module 54 includes a resistor R61 and a resistor R62, one end of the resistor R61 is connected to the fourth sampling terminal POGO_ADC_4, the other end of the resistor R61 is connected to one end of the resistor R62, and the other end of the resistor R62 is grounded.

[0054] In one embodiment, reference Figure 8 The mobile power rental system also includes an indicator light circuit 60, which includes a light emitting diode LED1, which is connected to the main control chip U3, and a resistor R40 is provided between the light emitting diode LED1 and the main control chip U3.

[0055] It should be understood that the above embodiments are only used to illustrate the technical solutions of the present utility model rather than to limit it. For those skilled in the art, the technical solutions described in the above embodiments can be modified, or some of the technical features therein can be replaced by equivalents; and all these modifications and replacements should fall within the scope of protection of the claims attached to the present utility model.

Claims

1. A power-off isolation circuit, used in a mobile power rental system, characterized in that: include: A first transistor and a second transistor, the base of the first transistor and the base of the second transistor are both connected to the power supply end of the mobile power rental system, the collector of the first transistor and the emitter of the second transistor are both connected to the main control end of the mobile power rental system, and the emitter of the first transistor and the collector of the second transistor are both connected to the external interface of the mobile power rental system.

2. The power-off isolation circuit according to claim 1, characterized in that: It also includes a first pull-up resistor and a second pull-up resistor, one end of the first pull-up resistor is connected to the power supply end of the mobile power rental system, and the other end of the first pull-up resistor is connected to the base of the first transistor; one end of the second pull-up resistor is connected to the power supply end of the mobile power rental system, and the other end of the second pull-up resistor is connected to the base of the second transistor.

3. A mobile power rental system, characterized in that: It comprises at least one power-off isolation circuit as described in any one of claims 1-2, and also comprises a main control circuit and an output circuit, and the number of the power-off isolation circuits is the same as the number of external interface pairs in the output circuit.

4. The mobile power rental system according to claim 3, characterized in that: The main control circuit includes a main control chip, and each of the power-off isolation circuits is respectively connected to different communication pins of the main control chip.

5. The mobile power rental system according to claim 4, characterized in that: A protection resistor is provided between the power-off isolation circuit and the communication pin of the main control chip.

6. The mobile power rental system according to claim 3, characterized in that: It also includes a power supply circuit, which includes an external interface power supply end and a system power supply end. The external interface power supply end is connected to the output circuit, and the system power supply end is connected to the power-off isolation circuit.

7. The mobile power rental system according to claim 6, characterized in that: The power supply circuit further includes a filter module, and the filter module is connected to the system power supply end.

8. The mobile power rental system according to claim 3, characterized in that: It also includes a sampling circuit, which includes a plurality of sampling modules. A sampling terminal is provided on each of the external interfaces, and each of the sampling modules is correspondingly connected to one of the sampling terminals.

9. The mobile power rental system according to claim 8, characterized in that: The sampling module includes a first sampling resistor and a second sampling resistor, and the first sampling resistor and the second sampling resistor are connected in series.

10. The mobile power rental system according to claim 4, characterized in that: It also includes an indicator light circuit, which includes a light emitting diode, and the light emitting diode is connected to the main control chip.

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