Power failure detection circuit and circuit board
By introducing a detection and protection module, including a voltage divider, current limiter, filter, and energy storage unit, between the power supply output terminal of the transformer module and the detection voltage input terminal of the control chip, the problems of large area occupation, high cost, and low safety of existing power failure detection circuits are solved, and safe and low-cost power failure detection is achieved.
Patent Information
- Application Number
- CN202423045288.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-10
- Publication Date
- 2025-12-19
- Estimated Expiration
- 2034-12-10
AI Technical Summary
Existing power failure detection circuits are directly connected to the mains power, resulting in large circuit board area, high cost, and low safety.
The power output terminal of the transformer module is connected to the detection voltage input terminal of the control chip through a detection and protection module, including a first filter energy storage unit and a voltage divider and current limiting unit, to prevent excessive or unstable voltage from affecting the control chip and reduce the number of components.
This technology enables a safe and low-cost method to detect whether the transformer output voltage has dropped, improving circuit safety and reducing the number of components required.
Smart Images
Figure CN223692439U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the technical field of power failure detection, and particularly relates to a power failure detection circuit and a circuit board. BACKGROUND
[0002] A transformer is an important circuit component of many high-power electrical equipment. The transformer can convert high voltage into low voltage, for example, can convert commercial power into the power required by electrical equipment to power the electrical equipment. Many existing electrical equipment will increase a power failure detection circuit at the input end of the transformer to facilitate users to understand whether the power supply is abnormal. However, the power failure detection circuit added at the input end of the transformer is directly connected with the commercial power, that is, the power failure detection circuit in the prior art is directly connected with high voltage. Therefore, the power failure circuit needs to be divided by multiple components to limit the current to protect the circuit safety, which leads to the problem of large circuit board area and high cost of the power failure circuit in PCB design. Moreover, once the power failure detection circuit is abnormal, it will cause great danger. Therefore, the power failure detection of the existing electrical equipment has the technical defects of low safety and high cost. SUMMARY
[0003] The utility model aims at overcoming the shortcomings and deficiencies in the prior art, and provides a power failure detection circuit and a circuit board, which can safely and low-cost detect whether the power supply voltage output by the transformer is in power failure.
[0004] One embodiment of the utility model provides a power failure detection circuit, which comprises a transformer module, a detection protection module and a control chip.
[0005] The power supply output end of the transformer module is connected with a load. The power supply output end of the transformer module is connected to the detection voltage input end of the control chip through the detection protection module. The control chip outputs a power failure detection signal according to the input of the detection voltage input end.
[0006] The power supply output end of the transformer module is connected with the input end of the first power supply protection unit.
[0007] The output end of the first power supply protection unit is connected with the first end of the voltage dividing and current limiting unit, and the second end of the voltage dividing and current limiting unit is connected with the detection voltage input end of the control chip.
[0008] The first end of the first filter energy storage unit is connected with the second end of the voltage dividing and current limiting unit, and the second end of the first filter energy storage unit is grounded.
[0009] One embodiment of the utility model provides a circuit board comprising the power failure detection circuit as described above.
[0010] With respect to the prior art, the power supply output end of the transformer module is connected to the detection voltage input end of the control chip through the detection protection module, so that the control chip can safely detect the power supply voltage, wherein the power supply output end of the transformer module is connected to the detection voltage input end of the control chip via the first power supply protection unit and the voltage division and current limiting unit, and the second end of the voltage division and current limiting unit is grounded via the first filter energy storage unit, which can prevent the control chip from being damaged by the excessively large voltage of the electrical signal output by the transformer module, and can also prevent the detection result of the control chip from being unstable due to the unstable electrical signal output by the transformer module, and since the transformer module outputs an electrical signal with a smaller voltage, the voltage division and current limiting unit uses fewer components, thereby achieving the technical effect of safely and low-cost detecting whether the power supply voltage output by the transformer appears a power failure.
[0011] In order to enable a clearer understanding of the present application, the specific embodiments of the present application will be described below in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS
[0012] Figure 1 The module connection diagram of the power failure detection circuit of an embodiment of the present application.
[0013] Figure 2 The circuit diagram of the power failure detection circuit of an embodiment of the present application.
[0014] Figure 3 The unit connection diagram of the power failure detection circuit of an embodiment of the present application.
[0015] Figure 4 The connection diagram of the voltage stabilizing output module of the power failure detection circuit of an embodiment of the present application.
[0016] Figure 5 The schematic diagram of the circuit board of an embodiment of the present application.
[0017] 10, power failure detection circuit; 11, transformer module; 13, detection protection module; 131, first power supply protection unit; 132, voltage division and current limiting unit; 133, first filter energy storage unit; 134, voltage protection unit; 135, first shunt unit; 136, filter unit; 137, current protection unit; 15, control chip; 17, voltage stabilizing output module; 100, circuit board. DETAILED DESCRIPTION
[0018] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of the present application.
[0019] Please refer to Figure 1 It is a module connection schematic diagram of the power failure detection circuit 10 of one embodiment of the present application, comprising: a transformer module 11, a detection protection module 13 and a control chip 15; the detection protection module 13 comprises a first power supply protection unit 131, a voltage division and current limiting unit 132 and a first filter energy storage unit 133.
[0020] The power supply output end of the transformer module 11 is connected with a load to output a power supply to the load; the power supply output end of the transformer module 11 is connected to the detection voltage input end of the control chip 15 through the detection protection module 13; the control chip 15 outputs a power failure detection signal according to the input of the detection voltage input end. Specifically, when the detection voltage input end of the control chip 15 has no input or the input voltage is less than a preset voltage threshold, the control chip 15 outputs a power failure detection signal to indicate that the power supply output of the transformer module 11 is abnormal.
[0021] Among them, the power supply output end of the transformer module 11 is connected with the input end of the first power supply protection unit 131.
[0022] The output end of the first power supply protection unit 131 is connected with the first end of the voltage division and current limiting unit 132, and the second end of the voltage division and current limiting unit 132 is connected with the detection voltage input end of the control chip 15.
[0023] The first end of the first filter energy storage unit 133 is connected with the second end of the voltage division and current limiting unit 132, and the second end of the first filter energy storage unit 133 is grounded.
[0024] Among them, the load refers to an electricity object running based on the power supply of the power supply output end of the transformer module 11, including but not limited to a chip, a circuit board 100 and a device based on the power supply of the power supply output end of the transformer module 11.
[0025] Please refer to Figure 2, the power supply output end of the transformer module 11 is the label 9 of the secondary coil NS1; the first power supply protection unit 131 comprises a diode DS5, wherein the anode of the diode is the input end of the first power supply protection unit 131, and the cathode of the diode is the output end of the first power supply protection unit 131, that is, the anode of the diode DS5 is connected with the label 9 of the secondary coil NS1, and the cathode of the diode DS5 is connected with the detection voltage input end of the control chip 15 through the voltage dividing and current limiting unit 132; the voltage dividing and current limiting unit 132 comprises a first resistor R76; the first filter energy storage unit 133 comprises a first capacitor C42; and the detection voltage input end of the control chip 15 is DEC ZO.
[0026] Wherein, the working principle of the embodiment is as follows: the secondary coil NS1 of the transformer module 11 supplies power to the load, and the electrical signal output by the secondary coil NS1 of the transformer module 11 is transmitted to the first capacitor C42 and the detection voltage input end DEC ZO of the control chip 15 through the diode DS5 and the first resistor R76, wherein the first capacitor C42 filters and stores the received electrical signal to prevent the output voltage of the secondary coil NS1 of the transformer module 11 from being unstable and affecting the detection result of the control chip 15, and the control chip 15 detects the voltage through the detection voltage input end DEC ZO to determine whether the secondary coil NS1 of the transformer module 11 stably supplies power to the load.
[0027] Compared with the prior art, the power supply output end of the transformer module 11 is connected to the detection voltage input end of the control chip 15 through the detection protection module 13, so that the control chip 15 can safely detect the power supply voltage, wherein the power supply output end of the transformer module 11 is connected to the detection voltage input end of the control chip 15 through the first power supply protection unit 131 and the voltage dividing and current limiting unit 132, and the second end of the voltage dividing and current limiting unit 132 is grounded through the first filter energy storage unit 133, which can prevent the electrical signal output by the transformer module 11 from damaging the control chip 15 due to excessive voltage, and can prevent the electrical signal output by the transformer module 11 from causing the detection result of the control chip 15 to be unstable due to instability, and since the transformer module 11 outputs an electrical signal with a small voltage, the voltage dividing and current limiting unit 132 uses fewer components, thereby achieving the technical effect of safely and low-cost detecting whether the power supply voltage output by the transformer appears a power failure.
[0028] Please refer to Figure 2 and Figure 3 In a feasible embodiment, the detection protection module 13 further comprises a voltage protection unit 134.
[0029] The first end of the voltage protection unit 134 is connected to the second end of the voltage dividing and current limiting unit 132, and the second end of the voltage protection unit 134 is grounded.
[0030] As Figure 2 shown, the voltage protection unit 134 includes a Zener diode ZD1, the cathode of the Zener diode is the first end of the first shunt unit 135, the anode of the Zener diode is the second end of the first shunt unit 135, that is, the anode of the Zener diode ZD1 is grounded, and the cathode of the Zener diode ZD1 is connected with the second end of the voltage division and current limiting unit 132, that is, the cathode of the Zener diode ZD1 is connected with the detection voltage input end DEC ZO of the control chip 15.
[0031] The working principle of the embodiment is as follows: when the voltage output by the transformer module 11 via the diode DS5 and the first resistor R76 is less than the reverse breakdown voltage of the Zener diode ZD1, the detection voltage input end DEC ZO of the control chip 15 can normally receive an electrical signal and perform voltage detection; when the voltage output by the transformer module 11 via the diode DS5 and the first resistor R76 is greater than or equal to the reverse breakdown voltage of the Zener diode ZD1, the Zener diode ZD1 is reversely conducted, so that the electrical signal output by the transformer module 11 via the diode DS5 and the first resistor R76 flows to the ground via the Zener diode ZD1, preventing a large voltage from acting on the detection voltage input end DEC ZO of the control chip 15 to damage the control chip 15.
[0032] In the embodiment, the control chip 15 can be protected by the voltage protection unit 134, improving the safety of the circuit.
[0033] Please refer to Figure 2 and Figure 3 In a feasible embodiment, the detection protection module 13 further includes a first shunt unit 135.
[0034] The first end of the first shunt unit 135 is connected with the second end of the voltage division and current limiting unit 132, and the second end of the first shunt unit 135 is grounded.
[0035] As Figure 2 shown, the first shunt unit 135 includes a second resistor R77, the first end of the second resistor R77 is connected with the second end of the voltage division and current limiting unit 132, that is, the first end of the second resistor R77 is connected with the detection voltage input end DEC ZO of the control chip 15, and the second end of the second resistor R77 is grounded. By the second resistor R77, the electrical signal output by the transformer module 11 via the diode DS5 and the first resistor R76 can be shunted to the ground, preventing a large current from acting on the detection voltage input end DEC ZO of the control chip 15 to damage the control chip 15.
[0036] In the embodiment, the control chip 15 can be protected by the first shunt unit 135, improving the safety of the circuit.
[0037] Referring to Figure 2 and Figure 3 In a feasible embodiment, the detection protection module 13 further comprises a filtering unit 136.
[0038] A first end of the filtering unit 136 is connected to an output end of the first power supply protection unit 131, and a second end of the filtering unit 136 is grounded.
[0039] As shown in Figure 2 , the filtering unit 136 comprises a capacitor CE15 and a capacitor C41, wherein a first end of the capacitor CE15 is connected to a cathode of a diode DS5, a second end of the capacitor CE15 is grounded, and the capacitor C41 is connected in parallel with the capacitor CE15. Both the capacitor CE15 and the capacitor C41 serve to store energy and filter, so as to store energy and filter the electrical signal output by the transformer module 11 via the diode DS5, thereby improving the stability and accuracy of power supply detection.
[0040] In the embodiment, the stability and accuracy of power supply detection by the control chip 15 can be improved through the filtering unit 136.
[0041] Referring to Figure 2 and Figure 3 In a feasible embodiment, the detection protection module 13 further comprises a current protection unit 137, and a second end of the voltage dividing and current limiting unit 132 is connected to a detection voltage input end of the control chip 15 through the current protection unit 137.
[0042] Referring to Figure 2 , the current protection unit 137 comprises a fuse J9, which is fused when the current output by the transformer module 11 via the diode DS5 and the first resistor R76 is too large, so as to prevent the large current from damaging the control chip 15 by acting on the detection voltage input end DEC ZO of the control chip 15.
[0043] In the embodiment, the control chip 15 can be protected through the current protection unit 137, thereby improving the safety of the circuit.
[0044] Referring to Figure 2 and Figure 4 In a feasible embodiment, the detection protection module 13 further comprises a voltage stabilizing output module 17, and a power supply output end of the transformer module 11 supplies power to a load through the voltage stabilizing output module 17.
[0045] The voltage stabilizing output module 17 comprises a second power supply protection unit and a second filter and energy storage unit; the power supply output end of the transformer module 11 is connected to the input end of the second power supply protection unit, and the output end of the second power supply protection unit is connected to the load; the output end of the second power supply protection unit is connected to the first end of the second filter and energy storage unit, and the second end of the second filter and energy storage unit is grounded.
[0046] Referring to Figure 2 , the second power supply protection unit comprises a diode DS2; the anode of the diode DS2 is connected to the label 9 of the secondary coil NS1, and the cathode of the diode DS2 is connected to the load; the second filter and energy storage unit comprises a capacitor CE5, the first end of the capacitor CE5 is connected to the cathode of the diode DS2, and the second end of the capacitor CE5 is grounded.
[0047] In this embodiment, the received electrical signal is filtered and stored by the capacitor CE5, which can improve the stability of the power supply to the load, and the diode DS2 can prevent the electrical signal from flowing back when the voltage of the capacitor CE5 is greater than the voltage of the power supply output end of the transformer module 11, thereby protecting the normal operation of the transformer.
[0048] In this embodiment, the second filter and energy storage unit can be used for filtering and storing energy to stabilize the power supply to the load, and the second power supply protection unit can be used to protect the normal operation of the transformer.
[0049] Referring to Figure 2 and Figure 4 , in a feasible embodiment, the voltage stabilizing output module 17 further comprises a shunt unit, the first end of the shunt unit is connected to the output end of the second power supply protection unit, and the second end of the shunt unit is grounded.
[0050] Referring to Figure 2 , the shunt unit comprises a resistor R26 and a resistor R27, and the cathode of the diode DS2 is respectively connected to the resistor R26 and the resistor R27.
[0051] In this embodiment, the electrical signal output by the transformer module 11 through the diode DS2 can be shunted to the ground through the resistor R26 and the resistor R27, so as to prevent the load from being damaged by a large current.
[0052] Referring to Figure 2 and Figure 4 , in a feasible embodiment, the voltage stabilizing output module 17 further comprises an inductive energy storage unit, and the output end of the second power supply protection unit is connected to the load through the inductive energy storage unit.
[0053] Referring to Figure 2The inductive energy storage unit comprises an inductor L3, when the current outputted by the transformer module 11 via the diode DS2 passes through the inductor L3, the inductor L3 stores energy, when the current outputted by the transformer module 11 via the diode DS2 changes, the inductor L3 releases the stored energy to enhance the current outputted to the load, so as to realize the stable output current to the load.
[0054] In the embodiment, the current stability of the transformer module 11 outputted to the load can be improved through the inductor L3.
[0055] Please refer to Figure 5 The second embodiment of the application provides a circuit board 100, which comprises the power-off detection circuit 10 as described above.
[0056] It should be noted that the circuit board provided by the second embodiment of the application and the power-off detection circuit of the first embodiment of the application belong to the same concept, and the implementation process is described in detail in the first embodiment, which will not be described here.
[0057] Although the embodiments of the application have been shown and described, it can be understood by those skilled in the art that various changes, modifications, replacements and modifications can be made to the embodiments without departing from the principles and spirits of the application, and the scope of the application is defined by the appended claims and their equivalents.
Claims
1. A power down detection circuit, characterized by, include: Transformer module, detection and protection module, and control chip; The detection and protection module includes a first power supply protection unit, a voltage divider and current limiting unit, and a first filter and energy storage unit. The power supply output terminal of the transformer module is connected to the load; the power supply output terminal of the transformer module is connected to the detection voltage input terminal of the control chip through the detection and protection module; the control chip outputs a power failure detection signal according to the input of the detection voltage input terminal. The power output terminal of the transformer module is connected to the input terminal of the first power protection unit; The output terminal of the first power supply protection unit is connected to the first terminal of the voltage divider and current limiting unit, and the second terminal of the voltage divider and current limiting unit is connected to the detection voltage input terminal of the control chip. The first end of the first filter energy storage unit is connected to the second end of the voltage divider and current limiting unit, and the second end of the first filter energy storage unit is grounded.
2. The power-down detection circuit of claim 1, wherein: The detection and protection module also includes a voltage protection unit and a first shunt unit; The first terminal of the voltage protection unit is connected to the second terminal of the voltage divider and current limiting unit, and the second terminal of the voltage protection unit is grounded. The first end of the first shunt unit is connected to the second end of the voltage divider and current limiting unit, and the second end of the first shunt unit is grounded.
3. The power down detection circuit of claim 2, wherein: The first power supply protection unit includes a diode, the voltage divider and current limiting unit includes a first resistor, the first filter and energy storage unit includes a first capacitor, the voltage protection unit includes a Zener diode, and the first shunt unit includes a second resistor. The anode of the diode is the input terminal of the first power supply protection unit, and the cathode of the diode is the output terminal of the first power supply protection unit; the cathode of the Zener diode is the first terminal of the first shunt unit, and the anode of the Zener diode is the second terminal of the first shunt unit.
4. The power down detection circuit of claim 1, wherein: The detection and protection module also includes a filtering unit; The first end of the filter unit is connected to the output end of the first power supply protection unit, and the second end of the filter unit is grounded.
5. The power down detection circuit of claim 1, wherein: The detection and protection module also includes a current protection unit; the second end of the voltage divider and current limiting unit is connected to the detection voltage input terminal of the control chip through the current protection unit.
6. The power down detection circuit of claim 1, wherein: It also includes a voltage regulator output module; the power supply output terminal of the transformer module supplies power to the load through the voltage regulator output module.
7. The power down detection circuit of claim 6, wherein: The voltage stabilization output module includes a second power supply protection unit and a second filter energy storage unit; The power supply output terminal of the transformer module is connected to the input terminal of the second power supply protection unit, and the output terminal of the second power supply protection unit is connected to the load; the output terminal of the second power supply protection unit is connected to the first terminal of the second filter energy storage unit, and the second terminal of the second filter energy storage unit is grounded.
8. The power-down detection circuit of claim 7, wherein: The voltage stabilization output module also includes a current shunt unit, the first end of which is connected to the output end of the second power supply protection unit, and the second end of which is grounded.
9. The power down detection circuit of claim 7, wherein: The voltage stabilization output module also includes an inductive energy storage unit, and the output terminal of the second power supply protection unit is connected to the load through the inductive energy storage unit.
10. A circuit board, characterized by Includes the power failure detection circuit as described in any one of claims 1-9.