Automatic start-up circuit of wireless cellular module and electronic device

Abstract

The utility model discloses an automatic starting circuit of wireless cellular module and electronic equipment, wherein, the automatic starting circuit includes control circuit, first starting circuit and second starting circuit, the output of control circuit is connected with the grid of first switch tube, the source of first switch tube is grounded, and the drain of first switch tube is connected with the switch machine pin of wireless cellular module, the control end of first starting circuit is connected with the external power supply end of wireless cellular module, and the output of first starting circuit is connected with the input of control circuit, the control end of second starting circuit is connected with the output of control circuit, and the output of second starting circuit is connected with the input of control circuit, and control circuit controls the level signal of switch machine pin of wireless cellular module according to the NAND result of level signal of the output of first starting circuit and the output of second starting circuit, makes wireless cellular module realize the automatic starting of anti power supply fluctuation, thereby, realize wireless cellular module steady starting.

Description

Technical Field

[0001] This utility model relates to the field of automatic power-on circuit technology, and more particularly to an automatic power-on circuit and electronic device for a wireless cellular module. Background Technology

[0002] To save costs, wireless cellular modules are often used as the main processor in many application designs, taking into account both communication and control. However, since there are no other MCUs (Microcontroller Units) on the circuit board, an automatic power-on circuit needs to be designed for the wireless cellular module. Currently, the automatic power-on circuit of the wireless cellular module usually pulls the power-on pin low to a low level for a period of time when the wireless cellular module is powered on, and then releases it to achieve automatic power-on of the wireless cellular module.

[0003] However, the problem with this technology is that the automatic power-on circuit will only trigger the automatic power-on process when the power is completely lost and then restored. If there is a short power outage when the external power supply of the wireless cellular module is unstable, the external power supply voltage will take some time to completely lose power because the external capacitor of the wireless cellular module is discharging. When the external power supply voltage drops below the protection voltage, the wireless cellular module will automatically shut down. If the external power supply voltage returns to normal before it completely loses power, the automatic power-on process will not be triggered, and the wireless cellular module will remain in the off state. Utility Model Content

[0004] This utility model aims to at least partially solve one of the technical problems in related technologies. Therefore, the first objective of this utility model is to provide an automatic power-on circuit for a wireless cellular module, which ensures that the wireless cellular module can automatically power on again after being shut down due to power supply fluctuations. This avoids the wireless cellular module failing to function properly due to power supply fluctuations and achieves stable power-on of the wireless cellular module.

[0005] The second objective of this invention is to provide an electronic device.

[0006] To achieve the above objectives, the first aspect of this utility model proposes an automatic power-on circuit for a wireless cellular module. The automatic power-on circuit includes: a control circuit, the output of which is connected to the gate of a first switching transistor, the source of which is grounded, and the drain of which is connected to the power-on pin of the wireless cellular module; a first power-on circuit, the control terminal of which is connected to the external power supply terminal of the wireless cellular module, and the output terminal of which is connected to the input terminal of the control circuit; and a second power-on circuit, the control terminal of which is connected to the output terminal of the control circuit, and the output terminal of which is connected to the input terminal of the control circuit. The control circuit is adapted to control the level signal of the power-on pin based on the AND-NOT result of the level signals of the output terminals of the first and second power-on circuits, thereby enabling the wireless cellular module to automatically power on against power supply fluctuations.

[0007] According to the automatic power-on circuit of the wireless cellular module of this utility model, the power-on and power-off status of the wireless cellular module is monitored by the first power-on circuit, and the power-on and power-off pin level signals of the wireless cellular module are controlled by the control circuit based on the AND-NOT result of the level signals of the output terminals of the first power-on circuit and the second power-on circuit. This ensures that the wireless cellular module can automatically power on again after being powered off due to power supply fluctuations, thereby avoiding the wireless cellular module from failing to work properly due to power supply fluctuations and achieving stable power-on of the wireless cellular module.

[0008] In addition, the automatic power-on circuit of the wireless cellular module described above according to this utility model may also have the following additional technical features: In some examples of this utility model, when the wireless cellular module is powered on, the external power supply terminal of the wireless cellular module outputs voltage to the voltage detection terminal of the automatic power-on circuit; when the wireless cellular module is powered off, the external power supply terminal of the wireless cellular module stops outputting voltage to the voltage detection terminal of the automatic power-on circuit.

[0009] In some examples of this utility model, the first power-on circuit includes: a first comparator, the non-inverting input terminal of the first comparator being connected to the voltage detection terminal of the automatic power-on circuit, the power supply terminal of the first comparator being connected to the power supply input terminal of the automatic power-on circuit, and the ground terminal of the first comparator being connected to the ground wire; and a first Zener diode circuit, the output terminal of the first Zener diode circuit being connected to the inverting input terminal of the first comparator.

[0010] In some examples of this utility model, the second power-on circuit includes: a second switching transistor, the gate of which is connected to the output terminal of the control circuit, the source of which is grounded, and the drain of which is connected to the delay control terminal of the automatic power-on circuit, wherein the delay capacitor disposed between the delay control terminal of the automatic power-on circuit and the ground wire discharges when the second switching transistor is turned on; a second comparator, the non-inverting input terminal of which is connected to the drain of the second switching transistor and the delay control terminal of the automatic power-on circuit, the power supply terminal of which is connected to the power supply input terminal of the automatic power-on circuit, and the ground terminal of which is connected to the ground wire; a second Zener diode circuit, the output terminal of which is connected to the inverting input terminal of the second comparator; and a constant current source, which is connected to the drain of the second switching transistor, the non-inverting input terminal of the second comparator, and the delay control terminal of the automatic power-on circuit.

[0011] In some examples of this utility model, the input terminal of the control circuit is connected to the power-on enable terminal of the automatic power-on circuit. The power-on enable terminal of the automatic power-on circuit, the power input terminal of the automatic power-on circuit, and the power input terminal of the wireless cellular module are all connected to the power supply circuit. When the level signal of the power-on enable terminal of the automatic power-on circuit is a high level signal, the control circuit is enabled.

[0012] In some examples of this utility model, when the enable terminal of the power-on circuit of the automatic power-on circuit changes from a low-level signal to a high-level signal, or when the output terminal of the first power-on circuit changes from a low-level signal to a high-level signal, the second switching transistor is turned on and then turned off by the control circuit.

[0013] In some examples of this utility model, when the level signal at the output terminal of the first power-on circuit is a low level signal, the first switching transistor is turned on by the control circuit, so that the level signal of the power-on pin of the wireless cellular module is a low level signal.

[0014] In some examples of this utility model, when the output signal of the first power-on circuit is a high-level signal, if the output signal of the second power-on circuit is a low-level signal, the first switch is turned on by the control circuit, so that the power-on pin of the wireless cellular module is a low-level signal; if the output signal of the second power-on circuit is a high-level signal, the first switch is turned off by the control circuit, so that the power-on pin of the wireless cellular module is a high-level signal.

[0015] In some examples of this invention, the first switch is in the on state when the level signal at the output of the control circuit is a high level signal, and the first switch is in the off state when the level signal at the output of the control circuit is a low level signal.

[0016] To achieve the above objectives, a second aspect of this utility model provides an electronic device including the automatic power-on circuit of the aforementioned wireless cellular module of this utility model.

[0017] According to the electronic device of this utility model, by adopting the aforementioned automatic power-on circuit of the wireless cellular module, it is possible to ensure that the wireless cellular module can be automatically powered on again after being powered off due to power fluctuations, thereby avoiding the wireless cellular module from failing to work properly due to power fluctuations and achieving stable power-on of the wireless cellular module.

[0018] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0019] Figure 1 The present invention provides an electrical schematic diagram of an automatic power-on circuit according to an embodiment of the present invention. Figure 2 This is a block diagram of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0020] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.

[0021] The automatic power-on circuit and electronic equipment of the wireless cellular module proposed in the present invention are described below with reference to the accompanying drawings.

[0022] Figure 1 This is an electrical schematic diagram of an automatic power-on circuit according to an embodiment of the present invention.

[0023] Specifically, in some examples of this utility model, reference is made to... Figure 1 As shown, the automatic power-on circuit 100 includes: a control circuit 110, a first power-on circuit 120, and a second power-on circuit 130.

[0024] In this circuit, the output of control circuit 110 is connected to the gate of first switching transistor Q1, the source of first switching transistor Q1 is grounded, and the drain of first switching transistor Q1 is connected to the power-on pin PWRKEY of wireless cellular module 200; the control terminal of first power-on circuit 120 is connected to the external power supply terminal VDD_EXT of wireless cellular module 200, and the output terminal of first power-on circuit 120 is connected to the input terminal of control circuit 110; the control terminal of second power-on circuit 130 is connected to the output terminal of control circuit 110, and the output terminal of second power-on circuit 130 is connected to the input terminal of control circuit 110; wherein, control circuit 110 is adapted to control the level signal of power-on pin PWRKEY according to the AND-NOT result of the level signals of the output terminals of first power-on circuit 120 and second power-on circuit 130, so that wireless cellular module 200 can automatically power on against power supply fluctuations.

[0025] It should be understood that in this example of the present invention, the first power-on circuit 120 determines the power-on / off state of the wireless cellular module 200 by monitoring the voltage signal output from the external power supply terminal of the wireless cellular module 200. For example, when the wireless cellular module 200 is in the power-off state, the output terminal of the first power-on circuit 120 is at a low level, and when the wireless cellular module 200 is in the power-on state, the output terminal of the first power-on circuit 120 is at a high level. Then, the control circuit 110 controls the level signal of the power-on / off pin PWRKEY of the wireless cellular module 200 based on the AND-NOT result of the level signals of the output terminals of the first power-on circuit 120 and the second power-on circuit 130, so as to ensure that the wireless cellular module 200 can automatically power on again after being powered off due to power supply fluctuations, thereby avoiding the wireless cellular module 200 from failing to work properly due to power supply fluctuations and improving the user experience.

[0026] Specifically, in this example of the present invention, when the wireless cellular module 200 is powered on, the control circuit 110 causes the output of the second power-on circuit 130 to first be low and then high. When the output of the second power-on circuit 130 is low, since the wireless cellular module 200 is in a powered-off state, the output of the first power-on circuit 120 is low. At this time, the level signals of the output of the first power-on circuit 120 and the output of the second power-on circuit 130 are both low-level signals (the NAND result is high). The output of the control circuit 110 is high, turning on the first switch Q1, thereby enabling the wireless cellular module 200 to power on. The power-on pin PWRKEY of the cellular module 200 is grounded. Subsequently, when the output of the second power-on circuit 130 is high, the wireless cellular module 200 has completed power-on. The output of the first power-on circuit 120 then becomes high. At this time, the level signals of the output of the first power-on circuit 120 and the output of the second power-on circuit 130 are both high (the NAND result is low). The control circuit 110 outputs a low level, turning off the first switch Q1, thereby restoring the power-on pin PWRKEY of the wireless cellular module 200 to a high level, thus realizing the automatic power-on of the wireless cellular module 200.

[0027] Additionally, when the wireless cellular module 200 triggers automatic shutdown due to power supply fluctuations, the output of the first power-on circuit 120 becomes low, while the output of the second power-on circuit 130 remains high. At this time, the output signal of the first power-on circuit 120 is low, while the output signal of the second power-on circuit 130 is high (the NAND result is high). The high-level output of the control circuit 110 turns on the first switch Q1, thereby grounding the power-on pin PWRKEY of the wireless cellular module 200. Subsequently, the wireless cellular module completes power-on, and the output of the first power-on circuit 120 becomes high. The control circuit 110 then makes the output of the second power-on circuit 130 first low and then high. When the output of the second power-on circuit 130 is low... The output signal of the first power-on circuit 120 is a high-level signal while the output signal of the second power-on circuit 130 is a low-level signal (the NAND result is high-level). The control circuit 110 outputs a high-level signal, turning on the first switch Q1, which in turn grounds the power-on pin PWRKEY of the wireless cellular module 200. Subsequently, when the output of the second power-on circuit 130 is high-level, the output signals of both the first power-on circuit 120 and the second power-on circuit 130 are high-level signals (the NAND result is low-level). The control circuit 110 outputs a low-level signal, turning off the first switch Q1, which in turn restores the power-on pin PWRKEY of the wireless cellular module 200 to a high level, ensuring that the wireless cellular module 200 can automatically power on again after being shut down due to power supply fluctuations.

[0028] Furthermore, in some examples of this utility model, reference is made to... Figure 1 As shown, when the wireless cellular module 200 is powered on, the external power supply terminal VDD_EXT of the wireless cellular module 200 outputs voltage to the voltage detection terminal IN of the automatic power-on circuit 100; when the wireless cellular module 200 is powered off, the external power supply terminal VDD_EXT of the wireless cellular module 200 stops outputting voltage to the voltage detection terminal IN of the automatic power-on circuit 100.

[0029] Specifically, in this example of the present invention, when the wireless cellular module 200 is in the powered-on state, the external power supply terminal VDD_EXT of the wireless cellular module 200 outputs voltage to the voltage detection terminal IN of the automatic power-on circuit 100; when the wireless cellular module 200 is in the powered-off state, the external power supply terminal VDD_EXT of the wireless cellular module 200 stops outputting voltage to the voltage detection terminal IN of the automatic power-on circuit 100, so that the automatic power-on circuit 100 can determine the power-on / off state of the wireless cellular module 200 by monitoring the voltage signal output by the external power supply terminal VDD_EXT of the wireless cellular module 200, thereby detecting whether the wireless cellular module has been powered off due to power supply fluctuations, and thus ensuring that the wireless cellular module 200 can be automatically powered on again after being powered off due to power supply fluctuations.

[0030] Furthermore, in some examples of this utility model, reference is made to... Figure 1 As shown, the first power-on circuit 120 includes: a first comparator U1, the non-inverting input terminal of the first comparator U1 is connected to the voltage detection terminal IN of the automatic power-on circuit 100, the power supply terminal of the first comparator U1 is connected to the power supply input terminal VCC of the automatic power-on circuit 100, and the ground terminal of the first comparator U1 is connected to the ground wire; and a first Zener diode circuit 121, the output terminal of the first Zener diode circuit 121 is connected to the inverting input terminal of the first comparator U1.

[0031] It should be understood that in this example of the present invention, when the wireless cellular module 200 is in the powered-on state, the external power supply terminal VDD_EXT of the wireless cellular module 200 outputs a 1.8V voltage to the voltage detection terminal IN of the automatic power-on circuit 100. When the wireless cellular module 200 is in the powered-off state, the external power supply terminal VDD_EXT of the wireless cellular module 200 stops outputting voltage to the voltage detection terminal IN of the automatic power-on circuit 100, which is equivalent to outputting a 0V voltage. In addition, the first Zener diode circuit 121 outputs a constant voltage of 1V.

[0032] Specifically, in this example of the present invention, the output voltage of the external power supply terminal VDD_EXT of the wireless cellular module 200 is input to the non-inverting input terminal of the first comparator U1 through the voltage detection terminal IN of the automatic power-on circuit 100, and a constant voltage is input to the inverting input terminal of the first comparator U1 through the first Zener diode circuit 121. This enables the first comparator U1 to convert the voltage signal output from the external power supply terminal VDD_EXT of the wireless cellular module 200 into a logic level signal and output it to the control circuit 110, so that the control circuit 110 can determine the power-on / off state of the wireless cellular module 200.

[0033] Optionally, in some examples of this invention, the first comparator U1 can be a Schmitt trigger.

[0034] It should be understood that in this example of the present invention, the voltage signal output from the external power supply terminal VDD_EXT of the wireless cellular module 200 to the voltage detection terminal IN of the automatic power-on circuit 100 may be unstable and fluctuate. Ordinary comparators have only one threshold voltage and are easily affected by interference, while Schmitt triggers have hysteresis characteristics, which are equivalent to having two threshold voltages. They can reverse the level only when the input voltage changes significantly, and have strong anti-interference capabilities.

[0035] Furthermore, in some examples of this utility model, reference is made to... Figure 1 As shown, the second power-on circuit 130 includes: a second switching transistor Q2, the gate of which is connected to the output terminal of the control circuit 110, the source of which is grounded, and the drain of which is connected to the delay control terminal CDELAY of the automatic power-on circuit 100. The delay capacitor C, located between the delay control terminal CDELAY and ground, discharges when the second switching transistor Q2 is turned on; and a second comparator U2, the non-inverting input of which is connected to the drain of the second switching transistor Q2. The delay control terminal CDELAY of the automatic power-on circuit 100 is connected to the power input terminal VCC of the automatic power-on circuit 100, and the ground terminal of the second comparator U2 is connected to the ground wire; the output terminal of the second Zener diode circuit 131 is connected to the inverting input terminal of the second comparator U2; the constant current source A is connected to the drain of the second switching transistor Q2, the non-inverting input terminal of the second comparator U2, and the delay control terminal CDELAY of the automatic power-on circuit 100.

[0036] It should be understood that in the above example of this utility model, the second Zener diode circuit 131 outputs a constant voltage of 1V. When the second switch Q2 is turned on, the delay capacitor C is grounded and discharged. At the same time, the non-inverting input terminal of the second comparator U2 is grounded, and the voltage at the non-inverting input terminal becomes 0V, which is lower than the 1V voltage input at the inverting input terminal of the second Zener diode circuit 131. Therefore, the output terminal of the second comparator U2 is at a low level at this time. When the second switch Q2 is turned off, the constant current source A charges the delay capacitor C, causing the voltage at the non-inverting input terminal of the second comparator U2 connected between the constant current source A and the delay capacitor C to continuously increase. Subsequently, when the voltage at the non-inverting input terminal of the second comparator U2 is higher than the 1V voltage input at the inverting input terminal of the second Zener diode circuit 131, the output terminal of the second comparator U2 is at a high level. Therefore, the control circuit 110 can control the second switch Q2 to turn on and off, so that the output of the second power-on circuit 130 is first at a low level and then at a high level. Then, the level signal of the power-on / off pin PWRKEY of the wireless cellular module 200 can be controlled according to the level signal of the output of the second power-on circuit 130, thereby realizing the automatic power-on of the wireless cellular module.

[0037] Furthermore, in some examples of this utility model, reference is made to... Figure 1 As shown, the input terminal of the control circuit 110 is connected to the power-on enable terminal ENABLE of the automatic power-on circuit 100. The power-on enable terminal ENABLE of the automatic power-on circuit 100, the power input terminal VCC of the automatic power-on circuit 100, and the power input terminal VBAT of the wireless cellular module 200 are all connected to the power supply circuit 300. When the power-on enable terminal ENABLE of the automatic power-on circuit 100 is a high-level signal, the control circuit 110 is enabled.

[0038] It should be understood that in the above example of this utility model, the power supply circuit 300 supplies power to both the wireless cellular module 200 and the automatic power-on circuit 100. When the power-on enable terminal ENABLE of the automatic power-on circuit 100 is a low-level signal, it indicates that the power supply to the wireless cellular module 200 or the automatic power-on circuit 100 is abnormal, and the control circuit 110 does not need to work. When the power-on enable terminal ENABLE of the automatic power-on circuit 100 is a high-level signal, it indicates that the power supply to the wireless cellular module 200 and the automatic power-on circuit 100 is normal, and the control circuit 110 can work normally.

[0039] Furthermore, in some examples of this utility model, when the enable terminal ENABLE of the automatic power-on circuit 100 changes from a low level signal to a high level signal, or when the output terminal of the first power-on circuit 120 changes from a low level signal to a high level signal, the second switch Q2 is turned on and then turned off by the control circuit 110.

[0040] It should be understood that in the above example of this utility model, when the enable terminal ENABLE of the power-on circuit 100 changes from a low level signal to a high level signal, it indicates that the wireless cellular module 200 is powered on. The control circuit 110 turns on the second switch Q2 and then turns it off, thus powering on the wireless cellular module 200. When the output terminal of the first power-on circuit 120 changes from a low level signal to a high level signal, it indicates that the wireless cellular module 200 has been powered on again after being powered off due to power supply fluctuations. The control circuit 110 turns on the second switch Q2 and then turns it off, thus restoring the power-on pin PWRKEY of the wireless cellular module 200 to a high level, so as to avoid affecting the power-on of the wireless cellular module 200 again.

[0041] Therefore, by changing the ENABLE signal of the power-on circuit of the automatic power-on circuit 100 from a low level signal to a high level signal, or by changing the output of the first power-on circuit 120 from a low level signal to a high level signal, the control circuit 110 turns on the second switch Q2 and then turns it off, so as to ensure that the wireless cellular module 200 can automatically power on when powered on. At the same time, it ensures that the wireless cellular module 200 can automatically power on again after being shut down due to power supply fluctuations, thereby realizing an automatic power-on circuit that prevents power supply fluctuations.

[0042] Furthermore, in some examples of this utility model, when the level signal at the output terminal of the first power-on circuit 120 is a low level signal, the first switch transistor Q1 is turned on by the control circuit 110, so that the level signal of the power-on / off pin PWRKEY of the wireless cellular module 200 is a low level signal.

[0043] It should be understood that in the above example of this utility model, when the wireless cellular module 200 is powered off due to power fluctuations, the output signal of the first power-on circuit 120 is a low-level signal and the output signal of the second power-on circuit 130 is a high-level signal (the NAND result is high). Therefore, the control circuit 110 turns on the first switch Q1, making the power-on pin PWRKEY of the wireless cellular module 200 a low-level signal, thereby powering on the wireless cellular module. This ensures that the wireless cellular module can automatically power on again after being powered off due to power fluctuations.

[0044] Furthermore, in some examples of this utility model, when the output signal of the first power-on circuit 120 is a high-level signal, if the output signal of the second power-on circuit 130 is a low-level signal, the first switch Q1 is turned on by the control circuit 110, so that the power-on pin PWRKEY of the wireless cellular module 200 is a low-level signal; if the output signal of the second power-on circuit 130 is a high-level signal, the first switch Q1 is turned off by the control circuit 110, so that the power-on pin PWRKEY of the wireless cellular module 200 is a high-level signal.

[0045] It should be understood that in the above example of this utility model, after the wireless cellular module 200 is powered off and then powered on again due to power supply fluctuations, the output level signal of the first power-on circuit 120 is a high-level signal. At this time, the control circuit 110 turns on the second switch Q2 and then turns it off, so that the power-on pin PWRKEY of the wireless cellular module 200 is restored to a high level, so as to avoid affecting the power-on of the wireless cellular module 200.

[0046] Specifically, in the above example of this utility model, when the second switch Q2 is turned on, the output signal of the second power-on circuit 130 is a low-level signal and the output signal of the first power-on circuit 120 is a high-level signal (the NAND result is high). Therefore, the control circuit 110 turns on the first switch Q1, thereby making the power-on pin PWRKEY of the wireless cellular module 200 a low-level signal. When the second switch Q2 is turned off, the output signal of the second power-on circuit 130 is a high-level signal and the output signal of the first power-on circuit 120 is a high-level signal (the NAND result is low). Therefore, the control circuit 110 turns off the first switch Q1, thereby making the power-on pin PWRKEY of the wireless cellular module 200 a high-level signal.

[0047] Furthermore, in some examples of this utility model, when the level signal at the output terminal of the control circuit 110 is a high level signal, the first switch Q1 is in the on state, and when the level signal at the output terminal of the control circuit 110 is a low level signal, the first switch Q1 is in the off state.

[0048] It should be understood that in the above examples of this utility model, the level signal at the output terminal of the control circuit 110 is the result of a logical AND-NOT operation between the level signals at the output terminals of the first power-on circuit 120 and the second power-on circuit 130. That is, when the level signals at the output terminals of the first power-on circuit 120 and the second power-on circuit 130 are both low, the level signal at the output terminal of the control circuit 110 is high; when the level signals at the output terminals of the first power-on circuit 120 and the second power-on circuit 130 are both high, the level signal at the output terminal of the control circuit 110 is low; when the level signal at the output terminal of the first power-on circuit 120 is low and the level signal at the output terminal of the second power-on circuit 130 is high, the level signal at the output terminal of the control circuit 110 is high; when the level signal at the output terminal of the first power-on circuit 120 is high and the level signal at the output terminal of the second power-on circuit 130 is low, the level signal at the output terminal of the control circuit 110 is high. In addition, the power-on / power-off pin PWRKEY of the wireless cellular module 200 is at a high level by default after external power supply. When the power-on / power-off pin PWRKEY of the wireless cellular module 200 changes from a low level to a high level for a period of time, the wireless cellular module 200 will execute the power-on process to power on. In order to enable the wireless cellular module 200 to power on again after being powered off due to power fluctuations, the power-on / power-off pin PWRKEY of the wireless cellular module 200 needs to be restored to a high level after power-on to avoid affecting the wireless cellular module's ability to power on again.

[0049] Specifically, in the above example of this utility model, when the level signal at the output terminal of the control circuit 110 is a high level signal, the first switch Q1 is in the on state, and when the level signal at the output terminal of the control circuit 110 is a low level signal, the first switch Q1 is in the off state, so as to control the on / off state of the first switch Q1 by the output level signal of the control circuit 110, thereby controlling the level signal of the power-on / off pin PWRKEY of the wireless cellular module 200, thereby realizing the automatic power-on of the wireless cellular module.

[0050] In summary, the automatic power-on circuit of the wireless cellular module of this utility model monitors the power-on / off status of the wireless cellular module through the first power-on circuit, and controls the level signal of the power-on / off pin of the wireless cellular module through the control circuit based on the level signals of the output terminals of the first and second power-on circuits. This ensures that the wireless cellular module can automatically power on again after being powered off due to power supply fluctuations, thereby avoiding the inability of the wireless cellular module to work properly due to power supply fluctuations and achieving stable power-on of the wireless cellular module.

[0051] Figure 2 This is a block diagram of an electronic device according to an embodiment of the present invention.

[0052] Specifically, in some examples of this utility model, reference is made to... Figure 2 As shown, the electronic device 1000 includes the automatic power-on circuit 100 and the wireless cellular module 200 of the aforementioned example of the present invention.

[0053] It should be understood that the specific implementation of the electronic device 1000 of this utility model can be referred to the specific implementation of the automatic power-on circuit 100 of the wireless cellular module in the example of this utility model mentioned above. In order to reduce redundancy, it will not be described again here.

[0054] In summary, the electronic device according to this utility model, by adopting the aforementioned automatic power-on circuit of the wireless cellular module, can ensure that the wireless cellular module can automatically power on again after being shut down due to power supply fluctuations, thereby avoiding the wireless cellular module from failing to work properly due to power supply fluctuations and achieving stable power-on of the wireless cellular module.

[0055] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0056] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0057] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0058] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0059] In this utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0060] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. An automatic power-on circuit for a wireless cellular module, characterized in that, The automatic power-on circuit includes: The control circuit has its output terminal connected to the gate of the first switching transistor, the source of the first switching transistor is grounded, and the drain of the first switching transistor is connected to the power-on pin of the wireless cellular module. The first power-on circuit has its control terminal connected to the external power supply terminal of the wireless cellular module, and its output terminal connected to the input terminal of the control circuit. The second power-on circuit has its control terminal connected to the output terminal of the control circuit, and its output terminal connected to the input terminal of the control circuit. The control circuit is adapted to control the level signal of the power-on / off pin based on the AND-NOT result of the level signals of the output terminals of the first power-on circuit and the second power-on circuit, so that the wireless cellular module can automatically power on without power fluctuations.

2. The automatic power-on circuit of the wireless cellular module according to claim 1, characterized in that, When the wireless cellular module is powered on, the external power supply terminal of the wireless cellular module outputs voltage to the voltage detection terminal of the automatic power-on circuit; when the wireless cellular module is powered off, the external power supply terminal of the wireless cellular module stops outputting voltage to the voltage detection terminal of the automatic power-on circuit.

3. The automatic power-on circuit of the wireless cellular module according to claim 2, characterized in that, The first power-on circuit includes: The first comparator has its non-inverting input connected to the voltage detection terminal of the automatic power-on circuit, its power supply terminal connected to the power input terminal of the automatic power-on circuit, and its ground terminal connected to the ground wire. The first Zener diode circuit has its output terminal connected to the inverting input terminal of the first comparator.

4. The automatic power-on circuit of the wireless cellular module according to claim 2, characterized in that, The second power-on circuit includes: The second switching transistor has its gate connected to the output terminal of the control circuit, its source grounded, and its drain connected to the delay control terminal of the automatic power-on circuit. The delay capacitor located between the delay control terminal of the automatic power-on circuit and the ground line discharges when the second switching transistor is turned on. The second comparator has its non-inverting input connected to the drain of the second switching transistor and the delay control terminal of the automatic power-on circuit, respectively. The power supply terminal of the second comparator is connected to the power supply input terminal of the automatic power-on circuit, and the ground terminal of the second comparator is connected to the ground wire. The output of the second Zener diode circuit is connected to the inverting input of the second comparator. A constant current source is connected to the drain of the second switching transistor, the non-inverting input of the second comparator, and the delay control terminal of the automatic power-on circuit.

5. The automatic power-on circuit of the wireless cellular module according to claim 4, characterized in that, The input terminal of the control circuit is connected to the power-on enable terminal of the automatic power-on circuit. The power-on enable terminal of the automatic power-on circuit, the power input terminal of the automatic power-on circuit, and the power input terminal of the wireless cellular module are all connected to the power supply circuit. When the level signal of the power-on enable terminal of the automatic power-on circuit is a high level signal, the control circuit is enabled.

6. The automatic power-on circuit of the wireless cellular module according to claim 5, characterized in that, When the enable terminal of the power-on circuit in the automatic power-on circuit changes from a low-level signal to a high-level signal, or when the output terminal of the first power-on circuit changes from a low-level signal to a high-level signal, the control circuit turns on the second switch and then turns it off.

7. The automatic power-on circuit of the wireless cellular module according to claim 1, characterized in that, When the output signal of the first power-on circuit is a low level signal, the control circuit turns on the first switch transistor, so that the power-on pin of the wireless cellular module is a low level signal.

8. The automatic power-on circuit of the wireless cellular module according to claim 1, characterized in that, When the output signal of the first power-on circuit is high, if the output signal of the second power-on circuit is low, the first switch is turned on by the control circuit, making the power-on pin of the wireless cellular module low; if the output signal of the second power-on circuit is high, the first switch is turned off by the control circuit, making the power-on pin of the wireless cellular module high.

9. The automatic power-on circuit of the wireless cellular module according to any one of claims 7-8, characterized in that, When the output signal of the control circuit is a high-level signal, the first switch is in the on state; and when the output signal of the control circuit is a low-level signal, the first switch is in the off state.

10. An electronic device, characterized in that, The electronic device includes a wireless cellular module and an automatic power-on circuit for the wireless cellular module as described in any one of claims 1-9.

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