CN111668809A - Power supply voltage control circuit and GPRS module - Google Patents
Power supply voltage control circuit and GPRS module Download PDFInfo
- Publication number
- CN111668809A CN111668809A CN202010564611.4A CN202010564611A CN111668809A CN 111668809 A CN111668809 A CN 111668809A CN 202010564611 A CN202010564611 A CN 202010564611A CN 111668809 A CN111668809 A CN 111668809A
- Authority
- CN
- China
- Prior art keywords
- voltage
- power supply
- circuit
- gprs module
- switch circuit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
- H02H3/20—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to excess voltage
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H1/00—Details of emergency protective circuit arrangements
- H02H1/0007—Details of emergency protective circuit arrangements concerning the detecting means
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H11/00—Emergency protective circuit arrangements for preventing the switching-on in case an undesired electric working condition might result
- H02H11/002—Emergency protective circuit arrangements for preventing the switching-on in case an undesired electric working condition might result in case of inverted polarity or connection; with switching for obtaining correct connection
Abstract
The embodiment of the invention relates to the technical field of automatic control, and discloses a power supply voltage control circuit and a GPRS module, wherein the power supply voltage control circuit comprises: the voltage detection circuit, the first switch circuit and the second switch circuit; the input end of the voltage detection circuit is connected with the power supply end of the power supply equipment, and the output end of the voltage detection circuit is connected with the input end of the first switch circuit; the output end of the first switch circuit is connected with the control end of the second switch circuit; the input end of the second switch circuit is connected with the power supply end of the power supply equipment, the control end of the second switch circuit is connected with the output end of the first switch circuit, and the output end of the second switch circuit is connected with the power utilization equipment; the second switch circuit controls the power supply end of the power supply device to supply power to the electric equipment according to the second control signal. Through the mode, the embodiment of the invention realizes the automatic control of the power supply voltage.
Description
Technical Field
The embodiment of the invention relates to the technical field of automatic control, in particular to a power supply voltage control circuit and a GPRS module.
Background
With the rapid development of the internet of things, the intellectualization of household electrical appliances becomes the trend of future development of household electrical appliances, and various wireless communication technologies are widely applied to the development and design of household electrical appliances.
The GPRS module is widely used as a wireless communication technology in home appliances. The GPRS module has higher requirement on the power supply voltage, and the GPRS module can be damaged and cannot be recovered if the external power supply is abnormal.
Disclosure of Invention
In view of the above problems, embodiments of the present invention provide a supply voltage control circuit and a GPRS module, which are used to solve the problem in the prior art that a GPRS module is damaged when external power supply is abnormal.
According to an aspect of an embodiment of the present invention, there is provided a supply voltage control circuit, including:
the voltage detection circuit, the first switch circuit and the second switch circuit;
the input end of the voltage detection circuit is connected with the power supply end of the power supply equipment, and the output end of the voltage detection circuit is connected with the input end of the first switch circuit; the voltage detection circuit detects the voltage of a power supply end of the power supply equipment and sends a first control signal to the first switch circuit according to a detection result;
the output end of the first switch circuit is connected with the control end of the second switch circuit; the first switch circuit sends a second control signal to the second switch circuit according to the first control signal;
the input end of the second switch circuit is connected with the power supply end of the power supply equipment, the control end of the second switch circuit is connected with the output end of the first switch circuit, and the output end of the second switch circuit is connected with the power utilization equipment; the second switch circuit controls a power supply end of the power supply equipment to supply power to the electric equipment according to the second control signal;
when the voltage of the power supply end of the power supply equipment is greater than the working voltage threshold of the electric equipment, the voltage detection circuit sends a first control signal for turning off to the first switch circuit, and the first switch circuit is turned off;
after the first switch circuit is turned off, the first switch circuit sends a second control signal for turning off to the second switch circuit, the second switch circuit is turned off, and the power supply end of the power supply device stops supplying power to the electric equipment.
In an optional mode, the voltage detection circuit comprises a first current limiting resistor, a first diode, a first voltage dividing resistor, a second voltage dividing resistor, a first noise reduction capacitor, a voltage comparator, a first filter capacitor and a first pull-up resistor;
one end of the first current-limiting resistor is connected with a power supply end of the power supply equipment, the other end of the first current-limiting resistor is connected with the anode of the first diode, and the cathode of the first diode is grounded;
the first voltage-dividing resistor and the second voltage-dividing resistor are connected in series between a power supply end of the power supply equipment and the ground, and the first noise-reduction capacitor is connected in parallel with the second voltage-dividing resistor;
the non-inverting input end of the voltage comparator is connected with the anode of the first diode and is used for fixing the voltage of the non-inverting input end of the voltage comparator to the voltage drop value of the first diode; the inverting input end of the voltage comparator is connected to the common end of the first voltage-dividing resistor and the second voltage-dividing resistor, and is used for taking the voltage-dividing value of the second voltage-dividing resistor to the voltage of the power supply end of the power supply device as the voltage of the inverting input end of the voltage comparator; a power supply end of the voltage comparator is respectively connected with a power supply end of the power supply equipment and one end of the first filter capacitor, and the other end of the first filter capacitor is grounded;
the first pull-up resistor is connected between a power supply end of the power supply device and an output end of the voltage comparator in parallel;
when the voltage of a power supply end of the power supply equipment is greater than the voltage of an overvoltage protection point, the voltage of an inverting input end of the voltage comparator is greater than the voltage of a non-inverting input end of the voltage comparator, and the voltage comparator outputs a first control signal with low level; otherwise, the voltage comparator outputs a first control signal of a high level through the first pull-up resistor.
In an alternative mode, the first switch circuit includes a third voltage dividing resistor, a fourth voltage dividing resistor and an NPN transistor;
one end of the third voltage-dividing resistor is connected with the output end of the voltage detection circuit, and the other end of the third voltage-dividing resistor is connected with the base electrode of the NPN type triode;
the fourth voltage-dividing resistor is connected between the base electrode and the emitter electrode of the NPN type triode in parallel, and the collector electrode of the NPN type triode is connected with the control end of the second switching circuit;
when the first control signal is a high-level control signal, the NPN type triode is conducted, and a collector of the NPN type triode sends a low-level second control signal to the second switch circuit;
when the first control signal is a low-level control signal, the NPN type triode is turned off, and a collector of the NPN type triode sends a high-level second control signal to the second switch circuit.
In an alternative mode, the second switch circuit includes a PMOS and a fifth voltage-dividing resistor;
the source electrode of the PMOS is connected with the power supply end of the power supply equipment, the grid electrode of the PMOS is connected with the output end of the first switch circuit, and the drain electrode of the PMOS is connected with the power utilization equipment;
the fifth voltage-dividing resistor is connected between the source and the gate of the PMOS in parallel;
when the second control signal is a low-level control signal, the PMOS is conducted, and a power supply end of the power supply equipment supplies power to the electric equipment;
and when the second control signal is a high-level control signal, the PMOS is turned off, and the power supply end of the power supply equipment stops supplying power to the electric equipment.
In an optional manner, the circuit further comprises: the reverse connection protection circuit is connected between a power supply end of the power supply equipment and an input end of the voltage detection circuit;
the reverse connection protection circuit comprises a second diode and a first voltage-stabilizing capacitor;
the anode of the second diode is grounded, and the cathode of the second diode is respectively connected with the power supply end of the power supply equipment and the input end of the voltage detection circuit;
the first voltage-stabilizing capacitor is connected in parallel with the second diode and is used for providing stable voltage for the input end of the voltage detection circuit;
when the power supply end of the power supply equipment is reversely connected, the second diode is conducted, and the voltage of the input end of the voltage detection circuit is the voltage drop of the second diode.
According to another aspect of the embodiments of the present invention, a GPRS module is provided, where the GPRS module includes a GPRS module and the above-mentioned supply voltage control circuit; the output end of the power supply voltage control circuit is connected with the power supply end of the GPRS module; and the power supply voltage control circuit is used for controlling a power supply end of the power supply equipment to supply power to the GPRS module.
In an optional manner, the GPRS module further includes a buck filter circuit;
the voltage reduction filter circuit is connected between the output end of the power supply voltage control circuit and the power supply end of the GPRS module and used for performing voltage reduction filter on the power supply end of the power supply equipment and then supplying power to the GPRS module.
In an alternative mode, the step-down filter circuit includes: the voltage reduction diode, the second voltage stabilization capacitor, the second noise reduction capacitor, the third noise reduction capacitor and the discharge resistor;
the anode of the step-down diode is connected with the output end of the power supply voltage control circuit, and the cathode of the step-down diode is connected with the power supply end of the GPRS module and used for stepping down the power supply end of the power supply equipment;
and the second voltage stabilizing capacitor, the second noise reduction capacitor, the third noise reduction capacitor and the discharge resistor are connected in parallel between the negative electrode of the voltage reduction diode and the ground and used for providing stable voltage for the GPRS module.
In an optional manner, the GPRS module further includes a communication level conversion circuit; the communication level conversion circuit comprises a signal receiving circuit and a signal sending circuit;
the input end of the signal receiving circuit is connected with the signal transmitting end of the power supply equipment, and the output end of the signal receiving circuit is connected with the signal receiving end of the GPRS module, and is used for converting the signal level sent by the power supply equipment into a signal level matched with the GPRS module and then sending the signal level to the GPRS module;
the input end of the signal sending circuit is connected with the signal transmitting end of the GPRS module, the output end of the signal sending circuit is connected with the signal receiving end of the power supply equipment, and the signal level sent by the GPRS module is converted into a signal level matched with the power supply equipment and then sent to the power supply equipment.
In an alternative form, the signal receiving circuit includes: a sixth voltage-dividing resistor, a seventh voltage-dividing resistor and a freewheeling diode;
the sixth voltage-dividing resistor and the seventh voltage-dividing resistor are connected in series between a signal transmitting end of the power supply equipment and the ground, and a common end of the sixth voltage-dividing resistor and the seventh voltage-dividing resistor is connected with a signal receiving end of the GPRS module; the seventh voltage-dividing resistor is used for dividing the signal level sent by the power supply equipment to obtain a signal level matched with the GPRS module;
the positive pole of the fly-wheel diode is connected with the signal receiving end of the GPRS module, the negative pole of the fly-wheel diode is connected with an external power supply, and the voltage of the external power supply is the same as the core working voltage of the GPRS module; the freewheeling diode is used for maintaining the signal level of the signal receiving end of the GPRS module.
In an alternative form, the signal transmission circuit includes: the second pull-up resistor, the first NPN type triode and the second current-limiting resistor;
the second pull-up resistor is connected between a signal receiving end and a power supply end of the power supply equipment;
a collector of the first NPN triode is connected with a signal receiving end of the power supply equipment, an emitter of the first NPN triode is connected with a signal transmitting end of the GPRS module, a base of the first NPN triode is connected with an external power supply through the second current-limiting resistor, and the voltage of the external power supply is the same as the core working voltage of the GPRS module;
when the signal level sent by the GPRS module is a high level, the first NPN type triode is cut off, and a signal receiving end of the power supply equipment receives the level of a power supply end of the power supply equipment;
when the signal level sent by the GPRS module is low level, the first NPN type triode is conducted, and the signal receiving end of the power supply equipment receives the signal level of the low level.
The embodiment of the invention detects the voltage provided by the power supply end of the power supply equipment through the voltage detection circuit and sends a first control signal to the first switch circuit according to the detection result; the first switch circuit sends a second control signal to the second switch circuit according to the first control signal, so that the second switch circuit controls the power supply end of the power supply device to supply power to the electric device according to the second control signal. By the aid of the mode, the power supply of the power supply equipment to the electric equipment is controlled, and when the voltage provided by the power supply equipment exceeds the working voltage threshold of the electric equipment, the power supply equipment can stop supplying power to the electric equipment through the power supply voltage control circuit provided by the embodiment of the invention, so that the electric equipment is prevented from being damaged. When the electric equipment is the GPRS module, the embodiment of the invention avoids the damage of the GPRS module when the power supply voltage of the power supply equipment is abnormal.
The foregoing description is only an overview of the technical solutions of the present invention, and the embodiments of the present invention are described below in order to make the technical means of the present invention more clearly understood and to make the above and other objects, features, and advantages of the present invention more clearly understandable.
Drawings
Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention. Also, like reference numerals are used to refer to like parts throughout the drawings. In the drawings:
fig. 1 is a block diagram illustrating a power supply voltage control circuit according to an embodiment of the present invention;
FIG. 2 illustrates a schematic diagram of a supply voltage control circuit provided by an embodiment of the present invention;
fig. 3 shows a block diagram of a GPRS module according to an embodiment of the present invention;
fig. 4 is a block diagram illustrating another GPRS module according to an embodiment of the present invention;
fig. 5 is a schematic diagram of a GPRS module according to an embodiment of the present invention.
The reference numbers in the detailed description are as follows:
The second switch circuit 30 has a first pull-up resistor R2 and a second noise reduction capacitor C1
The reverse connection protection circuit 40 has a third voltage dividing resistor R6 and a third noise reduction capacitor C2
The fourth voltage dividing resistor R7 of the voltage-reducing filter circuit 50 is discharged by the resistor R1
Communication level converting circuit 60 NPN type triode Q1 sixth voltage dividing resistor R10
Seventh voltage dividing resistor R9 of PMOS TR1 of signal receiving circuit 61
Fifth voltage divider resistor R3 of the signaling circuit 62 freewheeling diode D4
A first current limiting resistor R4, a second diode D1, a second pull-up resistor R11
A first diode D3, a first voltage-stabilizing capacitor EC1, a first NPN type triode Q2
A first divider resistor R5, a second diode D1, and a second current limiting resistor R12
Second voltage-dividing resistor R8 GPRS module U1
First noise reduction capacitor C5 supply voltage control circuit 100
Detailed Description
Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and therefore are only examples, and the protection scope of the present invention is not limited thereby.
The application scenario of the embodiment of the invention is the control of the output voltage of the power supply equipment when the power supply equipment supplies power to the electric equipment. The power supply device can be a power supply, and can also be any electrical equipment or electronic product. The electric device may be any electric device or electronic product, and the embodiment of the present invention is not limited thereto. The power supply end of the power supply device outputs a voltage signal to the power consumption device, and the voltage signal is controlled and output by the power supply voltage control circuit provided by the embodiment of the invention. When the voltage signal output by the power supply end of the power supply equipment is greater than the working voltage threshold of the electric equipment, the power supply voltage control circuit controls the power supply equipment to output voltage to the electric equipment, and therefore the electric equipment is prevented from being damaged. The following describes various embodiments of the present invention.
Referring to fig. 1, fig. 1 is a block diagram illustrating a power supply voltage control circuit according to an embodiment of the present invention, the power supply voltage control circuit including: a voltage detection circuit 10, a first switch circuit 20, and a second switch circuit 30. An input terminal of the voltage detection circuit 10 is connected to a power supply terminal of the power supply apparatus, and an output terminal of the voltage detection circuit 10 is connected to an input terminal of the first switch circuit 20. The voltage detection circuit 10 is configured to detect a voltage VIN at a power supply end of the power supply device to obtain a detection result, and send a first control signal to the first switch circuit 20 according to the detection result to control the first switch circuit 20 to be turned on or turned off.
The output terminal of the first switching circuit 20 is connected to the control terminal of the second switching circuit 30. The first switching circuit 20 is turned on or off according to the first control signal and transmits a corresponding second control signal to the second switching circuit 30.
The input end of the second switch circuit 30 is connected to the power supply end of the power supply device, the control end of the second switch circuit 30 is connected to the output end of the first switch circuit 20, and the output end of the second switch circuit 30 is connected to the power consumption device. The second switch circuit 30 controls the power source terminal of the power supply device to supply power to the electric device according to the second control signal.
When the voltage VIN of the power supply terminal of the power supply device is less than or equal to the working voltage threshold of the electric device, the voltage detection circuit 10 sends a first control signal for turning on to the first switch circuit 20, so that the first switch circuit 20 is turned on. After the first switch circuit 20 is turned on, the first switch circuit 20 sends an on second control signal to the second switch circuit 30 to turn on the second switch circuit 30, so that the power source end of the power supply device supplies power to the electric device through the second switch circuit 30.
When the voltage VIN at the power supply end of the power supply device is greater than the working voltage threshold of the electric device, the voltage detection circuit 10 sends a first control signal for turning off to the first switch circuit 20, so that the first switch circuit 20 is turned off. After the first switch circuit 20 is turned off, the first switch circuit 20 sends a second control signal for turning off to the second switch circuit 30, so that the second switch circuit 30 is turned off, and thus the power supply end of the power supply device is blocked by the second switch circuit 30 to stop supplying power to the electric equipment, and the power supply end of the power supply device is prevented from supplying voltage larger than the working voltage threshold of the electric equipment to damage the electric equipment.
In some embodiments, referring to fig. 2, fig. 2 is a schematic diagram of a supply voltage control circuit according to an embodiment of the present invention. As shown in fig. 2, the voltage detection circuit 10 includes a first current limiting resistor R4, a first diode D3, a first voltage dividing resistor R5, a second voltage dividing resistor R8, a first noise reduction capacitor C5, a voltage comparator U2, a first filter capacitor C4, and a first pull-up resistor R2. One end of the first current limiting resistor R4 is connected to a power supply terminal of the power supply apparatus, the other end of the first current limiting resistor R4 is connected to the anode of the first diode D3, and the cathode of the first diode D3 is grounded. The first voltage-dividing resistor R5 and the second voltage-dividing resistor R8 are connected in series between the power supply terminal of the power supply device and the ground, and the first noise reduction capacitor C5 is connected in parallel with the second voltage-dividing resistor R8. The non-inverting input end of the voltage comparator U2 is connected with the anode of the first diode D3, the inverting input end of the voltage comparator U2 is connected with the common end of the first voltage-dividing resistor R5 and the second voltage-dividing resistor R8, the power supply ends of the voltage comparator U2 are respectively connected with the power supply end of the power supply equipment and one end of the first filter capacitor C4, and the other end of the first filter capacitor C4 is grounded. The first pull-up resistor R2 is connected in parallel between the power supply terminal of the power supply device and the output terminal of the voltage comparator U2. The first diode D3 in the embodiment of the present invention may be any type of diode, and the embodiment of the present invention does not limit the specific type of the first diode D3, for example, in a specific implementation, the first diode D3 is a diode with the type FR-100. The voltage comparator U2 in the embodiment of the present invention may also be any type of voltage comparator, and the embodiment of the present invention is not limited to the type of the voltage comparator U2, for example, the type LM339 of the voltage comparator.
The first current limiting resistor R4 and the first diode D3 form a path, so that the voltage at the non-inverting input terminal of the voltage comparator U2 is the voltage drop value of the first diode D3. For a common diode, the voltage drop value is generally 0.7V, and the voltage of the non-inverting input terminal of the voltage comparator U2 is maintained at 0.7V. The voltage at the inverting input terminal of the voltage comparator U2 is the divided value of the voltage output by the power supply device through the second voltage-dividing resistor R8 and the first voltage-dividing resistor R5. The first noise reduction capacitor C5 reduces the noise of the voltage at the inverting input terminal of the voltage comparator U2, thereby inputting a stable voltage value to the inverting input terminal of the voltage comparator U2. The first filter capacitor C4 filters the voltage output by the power supply device and provides an operating voltage for the voltage comparator U2. The first pull-up resistor R2 is used to make the voltage comparator U2 output a high level.
When the voltage value output by the power supply equipment is smaller than or equal to the working voltage threshold of the electric equipment, the voltage division value of the second voltage division resistor R8 is smaller than or equal to the voltage drop value of the first diode D3, and the voltage comparator U2 outputs a first control signal with a high level.
When the voltage value output by the power supply equipment is greater than the working voltage threshold of the electric equipment, the voltage division value of the second voltage division resistor R8 is greater than the voltage drop value of the first diode D3, and the voltage comparator U2 outputs a first control signal with a low level through the first pull-up resistor R2.
It should be understood that the values of the first voltage-dividing resistor R5 and the second voltage-dividing resistor R8 are selected according to the operating voltage threshold of the powered device, so as to ensure that the divided voltage value of the second voltage-dividing resistor R8 is less than or equal to the voltage drop value of the first diode D3 when the voltage value output by the power supply device is less than or equal to the operating voltage threshold of the powered device.
Through the voltage detection circuit, the embodiment of the invention realizes the detection of the voltage value output by the power supply equipment, and outputs different first control signals according to the relation between the voltage value output by the power supply equipment and the working voltage threshold of the electric equipment so as to control the subsequent circuit.
In some embodiments, with continued reference to fig. 2, the first switch circuit 20 includes a third voltage dividing resistor R6, a fourth voltage dividing resistor R7, and an NPN transistor Q1. One end of the third voltage dividing resistor R6 is connected to the output end of the voltage detection circuit 10, and the other end of the third voltage dividing resistor R6 is connected to the base of the NPN transistor Q1. The fourth voltage dividing resistor R7 is connected in parallel between the base and the emitter of the NPN transistor Q1, and the collector of the NPN transistor Q1 is connected to the control terminal of the second switch circuit 30.
The fourth voltage dividing resistor R7 and the third voltage dividing resistor R6 divide the voltage of the first control signal output by the voltage detection circuit 10, so as to obtain the voltage between the base and the emitter of the NPN-type triode Q1. When the first control signal is a high-level control signal, the divided voltage value of the fourth voltage dividing resistor R7 is a high level, so that the NPN transistor Q1 is turned on, and the collector of the NPN transistor Q1 outputs a low-level second control signal. When the first control signal is a low-level control signal, the divided voltage value of the fourth voltage dividing resistor R7 is at a low level, so that the NPN transistor Q1 is turned off, and the collector of the NPN transistor Q1 outputs a high-level second control signal.
In some embodiments, with continued reference to fig. 2, the second switch circuit 30 includes a PMOS TR1 and a fifth voltage divider resistor R3. The source of PMOS TR1 is connected to the power supply terminal of the power supply device, the gate of PMOS TR1 is connected to the output terminal of the first switch circuit 20, and the drain of PMOS TR1 is connected to the power supply terminal of the power consumption device. The fifth voltage-dividing resistor R3 is connected in parallel between the source and the gate of the PMOS TR 1.
When the second control signal output from the first switch circuit 20 is a low-level control signal, the PMOS TR1 is turned on, and the power source terminal of the power supply device supplies power to the electric device. When the second control signal output by the first switch circuit 20 is a high-level control signal, the PMOS TR1 is turned off, and the power supply terminal of the power supply apparatus stops supplying power to the electric device.
When the second control signal output by the first switch circuit 20 is a low-level control signal, a current flows through the fifth voltage-dividing resistor, so that a steep rising edge is provided for the gate of the PMOS TR1, and the fast and reliable turning-on of the PMOS TR1 is ensured. When the second control signal output by the first switch circuit 20 is a high-level control signal, no current flows through the fifth voltage-dividing resistor R3, so that a steep falling edge is provided for the gate of the PMOS TR1, and the PMOS TR1 is ensured to be turned off quickly and reliably.
The overall operation of the schematic diagram shown in fig. 2 is explained below.
When the voltage value VIN output by the power supply device is less than or equal to the operating voltage threshold of the electric device, the voltage comparator U2 outputs a high-level first control signal, the high-level first control signal turns on the NPN transistor Q1, so that the collector of the NPN transistor Q1 outputs a low-level second control signal, and the low-level second control signal turns on the PMOS TR1, so that the power supply device supplies power to the electric device through the PMOS TR 1.
In the embodiment of the present invention, the voltage VIN provided by the power supply terminal of the power supply device is detected by the voltage detection circuit 10, and a first control signal is sent to the first switch circuit 20 according to the detection result; the first switch circuit 20 sends a second control signal to the second switch circuit 30 according to the first control signal, so that the second switch circuit 30 controls the power supply terminal of the power supply device to supply power to the electric device according to the second control signal. By the aid of the mode, the power supply of the power supply equipment to the electric equipment is controlled, and when the voltage provided by the power supply equipment exceeds the working voltage threshold of the electric equipment, the power supply equipment can stop supplying power to the electric equipment through the power supply voltage control circuit provided by the embodiment of the invention, so that the electric equipment is prevented from being damaged. When the electric equipment is the GPRS module, the embodiment of the invention avoids the damage of the GPRS module when the power supply voltage of the power supply equipment is abnormal.
Referring to fig. 2, in some embodiments, the supply voltage control circuit further includes a reverse connection protection circuit 40, and the reverse connection protection circuit 40 is connected between the power source terminal of the power supply device and the input terminal of the voltage detection circuit 10. The reverse connection protection circuit 40 includes a second diode D1 and a first stabilizing capacitor EC 1. The anode of the second diode D1 is grounded, and the cathode of the second diode D1 is connected to the power supply terminal of the power supply device and the input terminal of the voltage detection circuit 10, respectively. The first voltage stabilizing capacitor EC1 is connected in parallel with the second diode D1 for providing a stable voltage to the input terminal of the voltage detection circuit 10. When the power source terminals of the power supply apparatus are reversely connected, the second diode D1 is turned on, and the voltage at the input terminal of the voltage detection circuit 10 is a voltage drop of the second diode D1. When the polarity of the power source terminal of the power supply device is correct, the second diode D1 is turned off in the reverse direction, and the voltage at the input terminal of the voltage detection circuit 10 is the power source voltage VIN of the power supply device. Through the mode, the power supply end of the power supply equipment is prevented from being damaged when being reversely connected.
Fig. 3 shows a block diagram of a GPRS module according to an embodiment of the present invention, and as shown in fig. 3, the GPRS module according to the embodiment of the present invention includes a GPRS module U1 and a supply voltage control circuit 100. The supply voltage control circuit 100 in the embodiment of the present invention is a supply voltage control circuit provided in any one of the above-described embodiments, for example, the supply voltage control circuit shown in fig. 1 or fig. 2. The output end of the supply voltage control circuit 100 is connected to a power supply terminal VCC of the GPRS module U1, and the supply voltage control circuit 100 is configured to control the power supply device to supply power to the GPRS module U1. The GPRS module U1 in the embodiment of the present invention may be any type of GPRS module, and the embodiment of the present invention is not limited thereto. For example, in one particular embodiment, the GPRS module U1 is a GPRS module model G510-Q50-20.
The GPRS module provided by the embodiment of the invention can be directly used on any electronic equipment or electrical equipment and is used for providing communication for the electronic equipment or the electrical equipment. The GPRS module is powered by a power supply voltage VIN provided by a power supply end of the electronic equipment or the electrical equipment, and when the power supply voltage VIN is less than or equal to a working voltage VCC of the GRPS module U1, the GPRS module U1 can work normally; when the supply voltage is greater than the operating voltage VCC of the GPRS module U1, the supply voltage control circuit 100 blocks the supply voltage from supplying power to the GPRS module U1, thereby avoiding damage to the GPRS module U1. Therefore, the GPRS module provided by the embodiment of the present invention has a self-protection function on the premise of ensuring the self-function of the GPRS module U1, so as to avoid high-voltage damage and prolong the service life of the GPRS module.
In some embodiments, referring to fig. 4, the GPRS module further comprises a buck filter circuit 50. The voltage reduction filter circuit 50 is connected between the output end of the supply voltage control circuit 100 and a power supply end VCC of the GPRS module U1, and is configured to perform voltage reduction filtering on the voltage VIN of the power supply end of the power supply device and then supply power to the GPRS module U1 when VIN is less than or equal to VCC.
In some embodiments, referring to fig. 5, the buck filter circuit 50 includes a buck diode D2, a second stabilizing capacitor EC2, a second noise reduction capacitor C1, a third noise reduction capacitor C2, and a discharge resistor R1. The anode of the buck diode D2 is connected to the output terminal of the supply voltage control circuit 100, and the cathode of the buck diode D2 is connected to the power supply terminal of the GPRS module U1. The second voltage stabilizing capacitor EC2, the second noise reduction capacitor C1, the third noise reduction capacitor C2 and the discharge resistor R1 are connected in parallel between the negative electrode of the buck diode D2 and the ground.
When the power supply device supplies power to the GPRS module U1, the voltage VIN of the power supply device is stepped down by the step-down diode D2, and is stabilized and denoised by the second stabilizing capacitor EC2, the second denoising capacitor C1, and the third denoising capacitor C2, and then the power is supplied to the GPRS module U1. When the voltage VIN of the power supply device is lower than the regulated value of the second regulation capacitor EC2, the second regulation capacitor EC2 discharges. The discharge resistor R1 provides a discharge loop for the second stabilizing capacitor EC2 when the second stabilizing capacitor EC2 discharges. The voltage reduction filter circuit 50 can ensure that the power supply equipment can safely and reliably supply power to the GPRS module U1, and further ensures the power utilization safety of the GPRS module U1.
In some embodiments, referring to fig. 4, the GPRS module further comprises a communication level shifter 60. The communication level conversion circuit 60 includes a signal receiving circuit 61 and a signal transmitting circuit 62. The input end of the signal receiving circuit 61 is connected with the signal transmitting end OUT-TX of the power supply equipment, and the output end of the signal receiving circuit 61 is connected with the signal receiving end GPRS-RX of the GPRS module U1, and is used for converting the signal level sent by the power supply equipment into the signal level matched with the GPRS module U1 and then sending the signal level to the GPRS module U1. The input end of the signal sending circuit 62 is connected with the signal sending end GPRS-TX of the GPRS module U1, and the output end of the signal sending circuit 62 is connected with the signal receiving end OUT-RX of the power supply device, and is used for converting the signal level sent by the GPRS module U1 into a signal level matched with the power supply device and then sending the signal level to the power supply device.
In some embodiments, please refer to fig. 5, fig. 5 is a schematic circuit diagram of a GPRS module according to an embodiment of the present invention. The signal receiving circuit 61 includes: a sixth voltage-dividing resistor R10, a seventh voltage-dividing resistor R9, and a freewheeling diode D4. The sixth voltage-dividing resistor R10 and the seventh voltage-dividing resistor R9 are connected in series between the signal transmitting terminal OUT-TX of the power supply equipment and the ground, and the common terminal of the sixth voltage-dividing resistor R10 and the seventh voltage-dividing resistor R9 is connected with the signal receiving terminal GPRS-RX of the GPRS module U1. The anode of the freewheeling diode D4 is connected with the signal receiving terminal GPRS-RX of the GPRS module U1, and the cathode of the freewheeling diode D4 is connected with the external power supply VDD, wherein the voltage of the external power supply is the same as the core operating voltage VDD of the GPRS module U1. Inside the GPRS module, the core operating voltage VDD of the GPRS module is converted from the operating voltage of the GPRS module U1.
The seventh voltage-dividing resistor R9 is used for dividing the signal level sent by the power supply device to obtain a signal level matched with the GPRS module U1. For example, the signal level transmitted by the power supply device is 5V, and the signal level that the GPRS module U1 can receive is 3V, so that 5V × R9/(R9+ R10) ═ 3V. In one embodiment, R9 ═ 3.3K and R10 ═ 2K. The freewheeling diode D4 is used to maintain the signal level at the signal receiving end of the GPRS module U1 stable. Assuming that the voltage drop of the freewheeling diode D4 is 0.5V, the freewheeling diode D4 can maintain the signal level at the receiving terminal of the GPRS module U1 to be less than VDD +0.5V, so as to avoid that the GPRS module U1 cannot identify when the voltage value divided by the seventh voltage-dividing resistor R9 is higher than the core operating voltage VDD of the GPRS module U1. Through the mode, the signal level sent by the power supply equipment is converted into the signal level matched with the GPRS module U1, so that the GPRS module U1 can identify the signal sent by the power supply equipment, and the communication between the power supply equipment and the GPRS module U1 is realized.
In some embodiments, referring to fig. 5, the signal transmitting circuit 62 includes: a second pull-up resistor R11, a first NPN transistor Q2 and a second current limiting resistor R12. The second pull-up resistor R11 is connected between the signal receiving terminal OUT-RX of the power supply device and the power supply terminal VIN. The collector of the first NPN type triode Q2 is connected to a signal receiving terminal OUT-RX of the power supply device, the base of the first NPN type triode Q2 is connected to an external power supply VDD through a second current limiting resistor R12, and the voltage of the external power supply VDD is the same as the core operating voltage VDD of the GPRS module U1.
When the signal level sent by the GPRS module U1 is high, the first NPN transistor Q2 is turned off, and the signal receiving terminal OUT-RX of the power supply device receives the level VIN of the power supply terminal of the power supply device. When the signal level sent by the GPRS module U1 is a low level, the first NPN transistor Q2 is turned on, and the signal receiving terminal of the power supply device receives the signal level of the low level. In this way, the signal level sent by the GPRS module U1 is converted into a signal level matched with the power supply device, so that the power supply device can recognize the signal sent by the GPRS module U1, and communication between the GPRS module U1 and the power supply device is realized.
It is to be noted that technical or scientific terms used herein shall have the ordinary meaning as understood by those skilled in the art to which embodiments of the present invention belong, unless otherwise specified.
In the description of the present embodiments, the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", and the like, indicate orientations and positional relationships that are based on the orientations and positional relationships shown in the drawings, and are used only for convenience in describing the embodiments of the present invention and for simplicity in description, but do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the embodiments of the present invention.
Furthermore, the technical terms "first", "second", etc. are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. In the description of the embodiments of the present invention, "a plurality" means two or more unless specifically defined otherwise.
In the description of the novel embodiments of the present invention, unless explicitly stated or limited otherwise, the terms "mounted," "connected," and "fixed" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral part; mechanical connection or electrical connection is also possible; either directly or indirectly through intervening media, either internally or in any other relationship. Specific meanings of the above terms in the embodiments of the present invention can be understood by those of ordinary skill in the art according to specific situations.
In describing the novel embodiments of this embodiment, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through intervening media. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention, and they should be construed as being included in the following claims and description. In particular, the technical features mentioned in the embodiments can be combined in any way as long as there is no structural conflict. It is intended that the invention not be limited to the particular embodiments disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.
Claims (10)
1. A supply voltage control circuit, the circuit comprising:
the voltage detection circuit, the first switch circuit and the second switch circuit;
the input end of the voltage detection circuit is connected with the power supply end of the power supply equipment, and the output end of the voltage detection circuit is connected with the input end of the first switch circuit; the voltage detection circuit detects the voltage of a power supply end of the power supply equipment and sends a first control signal to the first switch circuit according to a detection result;
the output end of the first switch circuit is connected with the control end of the second switch circuit; the first switch circuit sends a second control signal to the second switch circuit according to the first control signal;
the input end of the second switch circuit is connected with the power supply end of the power supply equipment, the control end of the second switch circuit is connected with the output end of the first switch circuit, and the output end of the second switch circuit is connected with the power utilization equipment; the second switch circuit controls a power supply end of the power supply equipment to supply power to the electric equipment according to the second control signal;
when the voltage of the power supply end of the power supply equipment is greater than the working voltage threshold of the electric equipment, the voltage detection circuit sends a first control signal for turning off to the first switch circuit, and the first switch circuit is turned off;
after the first switch circuit is turned off, the first switch circuit sends a second control signal for turning off to the second switch circuit, the second switch circuit is turned off, and the power supply end of the power supply device stops supplying power to the electric equipment.
2. The circuit of claim 1, wherein the voltage detection circuit comprises a first current limiting resistor, a first diode, a first voltage dividing resistor, a second voltage dividing resistor, a first noise reduction capacitor, a voltage comparator, a first filter capacitor, and a first pull-up resistor;
one end of the first current-limiting resistor is connected with a power supply end of the power supply equipment, the other end of the first current-limiting resistor is connected with the anode of the first diode, and the cathode of the first diode is grounded;
the first voltage-dividing resistor and the second voltage-dividing resistor are connected in series between a power supply end of the power supply equipment and the ground, and the first noise-reduction capacitor is connected in parallel with the second voltage-dividing resistor;
the non-inverting input end of the voltage comparator is connected with the anode of the first diode and is used for fixing the voltage of the non-inverting input end of the voltage comparator to the voltage drop value of the first diode; the inverting input end of the voltage comparator is connected to the common end of the first voltage-dividing resistor and the second voltage-dividing resistor, and is used for taking the voltage-dividing value of the second voltage-dividing resistor to the voltage of the power supply end of the power supply device as the voltage of the inverting input end of the voltage comparator; a power supply end of the voltage comparator is respectively connected with a power supply end of the power supply equipment and one end of the first filter capacitor, and the other end of the first filter capacitor is grounded;
the first pull-up resistor is connected between a power supply end of the power supply device and an output end of the voltage comparator in parallel;
when the voltage of a power supply end of the power supply equipment is greater than the voltage of an overvoltage protection point, the voltage of an inverting input end of the voltage comparator is greater than the voltage of a non-inverting input end of the voltage comparator, and the voltage comparator outputs a first control signal with low level; otherwise, the voltage comparator outputs a first control signal of a high level through the first pull-up resistor.
3. The circuit of claim 1, wherein the first switching circuit comprises a third voltage dividing resistor, a fourth voltage dividing resistor, and an NPN transistor;
one end of the third voltage-dividing resistor is connected with the output end of the voltage detection circuit, and the other end of the third voltage-dividing resistor is connected with the base electrode of the NPN type triode;
the fourth voltage-dividing resistor is connected between the base electrode and the emitter electrode of the NPN type triode in parallel, and the collector electrode of the NPN type triode is connected with the control end of the second switching circuit;
when the first control signal is a high-level control signal, the NPN type triode is conducted, and a collector of the NPN type triode sends a low-level second control signal to the second switch circuit;
when the first control signal is a low-level control signal, the NPN type triode is turned off, and a collector of the NPN type triode sends a high-level second control signal to the second switch circuit.
4. The circuit of claim 1, wherein the second switch circuit comprises a PMOS and a fifth voltage divider resistor;
the source electrode of the PMOS is connected with the power supply end of the power supply equipment, the grid electrode of the PMOS is connected with the output end of the first switch circuit, and the drain electrode of the PMOS is connected with the power utilization equipment;
the fifth voltage-dividing resistor is connected between the source and the gate of the PMOS in parallel;
when the second control signal is a low-level control signal, the PMOS is conducted, and a power supply end of the power supply equipment supplies power to the electric equipment;
and when the second control signal is a high-level control signal, the PMOS is turned off, and the power supply end of the power supply equipment stops supplying power to the electric equipment.
5. The circuit of claim 1, further comprising: the reverse connection protection circuit is connected between a power supply end of the power supply equipment and an input end of the voltage detection circuit;
the reverse connection protection circuit comprises a second diode and a first voltage-stabilizing capacitor;
the anode of the second diode is grounded, and the cathode of the second diode is respectively connected with the power supply end of the power supply equipment and the input end of the voltage detection circuit;
the first voltage-stabilizing capacitor is connected in parallel with the second diode and is used for providing stable voltage for the input end of the voltage detection circuit;
when the power supply end of the power supply equipment is reversely connected, the second diode is conducted, and the voltage of the input end of the voltage detection circuit is the voltage drop of the second diode.
6. A GPRS module comprising a GPRS module and a supply voltage control circuit according to any of claims 1-5; the output end of the power supply voltage control circuit is connected with the power supply end of the GPRS module; and the power supply voltage control circuit is used for controlling a power supply end of the power supply equipment to supply power to the GPRS module.
7. The GPRS module of claim 6, wherein the GPRS module further comprises a buck filter circuit;
the voltage reduction filter circuit is connected between the output end of the power supply voltage control circuit and the power supply end of the GPRS module and used for performing voltage reduction filter on the power supply end of the power supply equipment and then supplying power to the GPRS module.
8. The GPRS module of claim 7, wherein the buck filter circuit comprises: the voltage reduction diode, the second voltage stabilization capacitor, the second noise reduction capacitor, the third noise reduction capacitor and the discharge resistor;
the anode of the step-down diode is connected with the output end of the power supply voltage control circuit, and the cathode of the step-down diode is connected with the power supply end of the GPRS module and used for stepping down the power supply end of the power supply equipment;
and the second voltage stabilizing capacitor, the second noise reduction capacitor, the third noise reduction capacitor and the discharge resistor are connected in parallel between the negative electrode of the voltage reduction diode and the ground and used for providing stable voltage for the GPRS module.
9. The GPRS module of claim 6, wherein the GPRS module further comprises a communication level conversion circuit; the communication level conversion circuit comprises a signal receiving circuit and a signal sending circuit;
the input end of the signal receiving circuit is connected with the signal transmitting end of the power supply equipment, and the output end of the signal receiving circuit is connected with the signal receiving end of the GPRS module, and is used for converting the signal level sent by the power supply equipment into a signal level matched with the GPRS module and then sending the signal level to the GPRS module;
the input end of the signal sending circuit is connected with the signal transmitting end of the GPRS module, the output end of the signal sending circuit is connected with the signal receiving end of the power supply equipment, and the signal level sent by the GPRS module is converted into a signal level matched with the power supply equipment and then sent to the power supply equipment.
10. The GPRS module of claim 9, wherein the signal receiving circuit comprises: a sixth voltage-dividing resistor, a seventh voltage-dividing resistor and a freewheeling diode;
the sixth voltage-dividing resistor and the seventh voltage-dividing resistor are connected in series between a signal transmitting end of the power supply equipment and the ground, and a common end of the sixth voltage-dividing resistor and the seventh voltage-dividing resistor is connected with a signal receiving end of the GPRS module; the seventh voltage-dividing resistor is used for dividing the signal level sent by the power supply equipment to obtain a signal level matched with the GPRS module;
the positive pole of the fly-wheel diode is connected with the signal receiving end of the GPRS module, the negative pole of the fly-wheel diode is connected with an external power supply, and the voltage of the external power supply is the same as the core working voltage of the GPRS module; the freewheeling diode is used for maintaining the signal level of the signal receiving end of the GPRS module;
the signal transmission circuit includes: the second pull-up resistor, the first NPN type triode and the second current-limiting resistor;
the second pull-up resistor is connected between a signal receiving end and a power supply end of the power supply equipment;
a collector of the first NPN triode is connected with a signal receiving end of the power supply equipment, an emitter of the first NPN triode is connected with a signal transmitting end of the GPRS module, a base of the first NPN triode is connected with an external power supply through the second current-limiting resistor, and the voltage of the external power supply is the same as the core working voltage of the GPRS module;
when the signal level sent by the GPRS module is a high level, the first NPN type triode is cut off, and a signal receiving end of the power supply equipment receives the level of a power supply end of the power supply equipment;
when the signal level sent by the GPRS module is low level, the first NPN type triode is conducted, and the signal receiving end of the power supply equipment receives the signal level of the low level.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010564611.4A CN111668809A (en) | 2020-06-19 | 2020-06-19 | Power supply voltage control circuit and GPRS module |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010564611.4A CN111668809A (en) | 2020-06-19 | 2020-06-19 | Power supply voltage control circuit and GPRS module |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111668809A true CN111668809A (en) | 2020-09-15 |
Family
ID=72389040
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010564611.4A Pending CN111668809A (en) | 2020-06-19 | 2020-06-19 | Power supply voltage control circuit and GPRS module |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111668809A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114301154A (en) * | 2020-09-22 | 2022-04-08 | 西安诺瓦星云科技股份有限公司 | Power supply backup control panel, display controller and LED display control system |
| CN115460734A (en) * | 2022-05-17 | 2022-12-09 | 深圳锐盟半导体有限公司 | LED control circuit, electronic equipment and electronic device |
| CN116647028A (en) * | 2023-05-23 | 2023-08-25 | 小米汽车科技有限公司 | Switching power supply control circuit, vehicle-mounted system and vehicle |
-
2020
- 2020-06-19 CN CN202010564611.4A patent/CN111668809A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114301154A (en) * | 2020-09-22 | 2022-04-08 | 西安诺瓦星云科技股份有限公司 | Power supply backup control panel, display controller and LED display control system |
| CN115460734A (en) * | 2022-05-17 | 2022-12-09 | 深圳锐盟半导体有限公司 | LED control circuit, electronic equipment and electronic device |
| CN115460734B (en) * | 2022-05-17 | 2023-12-01 | 深圳锐盟半导体有限公司 | LED control circuit, electronic equipment and electronic device |
| CN116647028A (en) * | 2023-05-23 | 2023-08-25 | 小米汽车科技有限公司 | Switching power supply control circuit, vehicle-mounted system and vehicle |
| CN116647028B (en) * | 2023-05-23 | 2024-04-26 | 小米汽车科技有限公司 | Switching power supply control circuit, vehicle-mounted system and vehicle |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111668809A (en) | Power supply voltage control circuit and GPRS module | |
| US20120262950A1 (en) | Power supply adaptor | |
| US9293983B2 (en) | Switching power-supply apparatus | |
| US9667055B2 (en) | Over-voltage protection apparatus and method of operating the same | |
| US20140062421A1 (en) | Discharging circuit, image forming apparatus having the discharging circuit, and power supply unit | |
| WO2020037912A1 (en) | Beidou navigation system based vehicle-mounted inteligent terminal | |
| JP2021503873A (en) | NFC antenna power acquisition device | |
| US20140184154A1 (en) | Electronic component, power receiving device, and power feeding system | |
| CN103502649A (en) | A system and method of remotely connecting and disconnecting the auxiliary power supply of a frequency inverter for variable capacity compressor employed in cooling systems | |
| CN212380932U (en) | Power supply voltage control circuit and GPRS module | |
| US20090161397A1 (en) | Computer power supply | |
| CN108683217B (en) | Power supply voltage monitoring circuit capable of being turned off | |
| CN110143111B (en) | Vehicle-mounted air conditioner power supply circuit, vehicle-mounted electric control device and vehicle-mounted air conditioner | |
| CN115051443A (en) | Camera power supply device for unmanned vehicle and unmanned vehicle | |
| US9627922B2 (en) | Active load circuit | |
| CN210591717U (en) | Control complete machine current circuit and on-vehicle accuse in control vehicle-mounted | |
| CN219697308U (en) | Power supply circuit, variable frequency control circuit and refrigerator | |
| US10338671B2 (en) | Power supply circuit and power supply system | |
| CN113141104B (en) | Power panel | |
| CN218603204U (en) | Power supply system and electric toothbrush | |
| CN111009958A (en) | Power supply control circuit | |
| CN215646227U (en) | Low-power protection circuit and mobile communication device | |
| CN220628878U (en) | Battery reverse connection preventing circuit and electronic equipment | |
| CN116960911B (en) | Current-limiting protection circuit, power supply circuit and energy storage power supply | |
| CN116961378B (en) | AC-DC switching power supply and control method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |