Circuit automatic control and power monitoring device and design method thereof

Abstract

The invention discloses a circuit automatic control and power monitoring device and a design method thereof, and the device comprises a programmable single-chip microcomputer chip, and a voltage reduction circuit, a filter circuit, a voltage and current sampling circuit, a relay control circuit, a display screen control circuit and an external communication circuit which are connected with the single-chip microcomputer chip. A to-be-detected circuit can be monitored in real time, and the state of the to-be-detected circuit is obtained through the voltage and current sampling circuit; according to a preset monitoring mode and the state of the to-be-detected circuit, information early warning and circuit on-off control are carried out, and automatic control and monitoring of the circuit are achieved; meanwhile, the on-off of the circuit can be manually controlled through the external communication circuit, and a preset detection mode can be changed. Through reasonable layout and integrated design, the measuring range is increased while the overall size of the device is reduced, and the reliability is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic circuits, and in particular to a circuit automatic control and monitoring technology. Background Art

[0002] At present, with the design and production of a large number of electronic products, the market demand for measuring instruments is increasing, especially in the field of electronic design and debugging, there is a lack of a simple and reliable circuit control and monitoring device. Compared with the single current and voltage measurement, the power measurement is slightly difficult due to the superposition of errors. At the same time, due to the interference of various environmental factors, the measurement accuracy will also be reduced. Automatic control is even more important. When the circuit operation is abnormal, timely cutting off the circuit can often prevent the circuit from burning or even major accidents.

[0003] Early power measuring instruments were heavy and bulky, and could not meet the requirements of debugging on the move. In addition, there were some simple digital meters that could measure voltage and current, but they had small ranges and could not be automatically controlled, and could not meet the requirements in the field of electronic debugging. There are no electronic devices on the market that are both miniaturized, high-power, and have real-time circuit monitoring and automatic control. In the field of electronic design debugging, such as the debugging of robots and automatic vehicles, there are requirements for such devices to be highly integrated, have a high range, be automatically controlled, and be able to monitor in real time. Summary of the invention

[0004] The present invention provides a circuit automatic control and power monitoring device and a design method thereof, which solves the problems that the existing related devices have a small range, cannot be automatically controlled, have a low integration level, result in a large weight and volume, and are inconvenient to use.

[0005] The present invention provides a circuit automatic control and power monitoring device, comprising a single-chip microcomputer chip, wherein a filter circuit is connected around the pins of the single-chip microcomputer chip to stabilize the voltage input to the single-chip microcomputer chip and the ADC sampling voltage;

[0006] The power pin of the single-chip microcomputer chip is connected to a step-down circuit, which reduces the voltage in the circuit to be tested to 3.3V for the single-chip microcomputer chip and other modules to work;

[0007] The single-chip microcomputer chip is connected to the communication pin of the screen FPC terminal, and communicates with the display screen through a communication protocol such as SPI to achieve light control and content display of the display screen;

[0008] The power pin of the screen FPC terminal is connected to the screen boost circuit to boost 3.3V to the voltage required for the screen to work;

[0009] Preferably, the power inductor used in the screen boost circuit is a small-volume packaged inductor, which is square in shape with a length and width of 2.5 mm*2 mm;

[0010] The step-down circuit is connected to the circuit to be tested via the input and output ports of the circuit to be tested, and each port of the input and output ports of the circuit to be tested is divided into a positive port (+) and a negative port (-);

[0011] A relay circuit is connected in series between the input end and the output end of the positive electrode port of the circuit to be tested, and the closing and opening of the circuit can be controlled by the relay control circuit.

[0012] The relay control circuit is composed of a transistor, a Schottky diode and necessary resistors, the base of the transistor is connected to the control pin of the single-chip microcomputer chip, and can be controlled by the single-chip microcomputer chip;

[0013] A current sampling chip is connected in series between the input end and the output end of the negative electrode port of the circuit to be tested, and is connected to the ADC sampling pin of the single-chip microcomputer chip through the current sampling circuit;

[0014] The control pin of the single chip microcomputer circuit is connected to the indicator light circuit to control the on and off of the indicator light;

[0015] The input pin of the single-chip microcomputer chip is connected to the key circuit, so that the user can input corresponding instructions by pressing keys;

[0016] The circuit automatic control and power monitoring device adopts a double-layer circuit board design, the upper layer is mainly digital circuit, and the lower layer is mainly analog circuit and circuit to be tested, so as to reduce the inductive current interference phenomenon generated in the circuit;

[0017] The circuit automatic control and power monitoring device has an applicable voltage range of 5-40V, an applicable current range of 0-35A, a maximum power bearing capacity of 1400W, a length of 57mm, a width of 25mm, a height of 29mm, and a volume of 0.00004m 3 .

[0018] Preferably, The upper circuit and the lower circuit of the circuit automatic control and power monitoring device are connected through the upper and lower circuit connection terminals.

[0019] Preferably, The upper circuit layer, the lower circuit layer and the display panel layer of the circuit automatic control and power monitoring device are fixed through through holes located at the four corners of each layer.

[0020] Preferably, the display panel layer of the circuit automatic control and power monitoring device is located directly above the upper circuit layer, and the screen and indicator light areas corresponding to the upper circuit board are made transparent.

[0021] Preferably, the circuit board wires between the input end and the output end of the positive port and the negative port of the circuit to be tested are exposed without oil covering and then covered with a solder layer.

[0022] Preferably, the step-down circuit is a two-stage step-down structure, the first-stage step-down circuit reduces the voltage of the circuit to be tested to 5V, and supplies power to the relay circuit and the voltage and current sampling circuit, and then the second-stage step-down circuit reduces the 5V to 3.3V, and supplies power to the single-chip microcomputer chip, screen FPC terminal, communication circuit interface, key circuit, and relay control circuit.

[0023] Preferably, the external display screen is fixed on the front side of the upper circuit board, located between the upper circuit layer and the display panel layer, and its FPC cable passes through the screen FPC cable via hole and is connected to the FPC terminal on the back side of the upper circuit layer.

[0024] Preferably, the communication circuit interface and the screen FPC terminal are both pluggable structures, and the external communication module and external display screen connected thereto can be replaced at any time according to specific needs.

[0025] A method for designing a circuit automatic control and power monitoring device, the method for designing the circuit automatic control and power monitoring device comprises the following steps:

[0026] Determine the specifications of the buck chip and relay in the buck circuit according to the possible current and voltage range of the circuit to be tested;

[0027] Determine the size of the lower circuit board and the distance between the upper and lower circuit boards according to the package size of the relay;

[0028] Determine the circuit board wire processing method between the input and output ends and the thickness of the solder layer according to the current size and continuous working time of the circuit to be tested;

[0029] Determine the pin sequence of the communication circuit interface and the screen FPC terminal according to the pin sequence of the external communication module and the external LCD screen;

[0030] Determine the voltage boost size of the boost circuit according to the voltage characteristics of the external LCD screen;

[0031] Determine the amplification ratio of the operational amplifier in the voltage and current sampling circuit according to the possible voltage and current range of the circuit to be tested;

[0032] According to the upper and lower circuit boards, the upper and lower circuit connection terminals are used for connection, and the through holes located at the four corners of each layer are used for fixing.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] The present invention integrates a single-chip microcomputer chip, a step-down circuit, a filter circuit, a voltage and current sampling circuit, a relay circuit and a control circuit, a display screen control circuit, and an external communication circuit. Through reasonable layout and integrated design, the overall volume is reduced while the range and reliability are increased. Through a multi-layer combined design, connecting terminals are used to achieve inter-layer connection, and lightweight and miniaturization are achieved. At the same time, a multi-stage step-down circuit is used, and there is no need to connect to an external power supply. It only needs to be connected to the circuit to be tested to work. Through the single-chip microcomputer chip, the power of the calculation circuit can be measured and calculated in real time, and buttons can be used for interaction to automatically control the on and off of the circuit, thereby improving the reliability and practicality of the overall system. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0036] Figure 1 This is a schematic diagram of the overall structure of the present invention, wherein the through holes (16) located at the four corners of the square surface need to be fixed using a fixing method such as copper pillars and screws to fix the display panel layer (7), the upper circuit layer (17), and the lower circuit layer (18) to keep the relative positions of the three layers unchanged.

[0037] Figure 2 is a schematic diagram of the front structure of the upper circuit layer (17) and the lower circuit layer (18) of the present invention, wherein the upper and lower connection terminal male connectors (1-1) and female connectors (1-2) are connected to each other after assembly, and the male connectors and female connectors are connected to each other after assembly. Figure 1 , 2 The length is for reference only and does not represent the actual length.

[0038] Figure 3 It is a schematic diagram of the reverse structure of the upper circuit layer (17) and the lower circuit layer (18) of the present invention.

[0039] Explanation of the numbers in the figure: 1-1 and 1-2-upper and lower circuit connection terminals, 2-button, 3-communication circuit interface, 4-1-screen position, 4-2-screen FPC cable through hole, 4-3-screen FPC terminal, 5-1 and 5-2-input and output ports of the circuit to be tested, 6-relay module, 7-display panel layer, 8-single-chip microcomputer chip, 9-reserved expansion position, 10-communication circuit interface, 11-screen boost circuit, 12-step-down circuit, 13-voltage sampling circuit, 14-crystal oscillator circuit, 15-current sampling circuit, 16-through hole, 17-upper circuit layer, 18-lower circuit layer, 19-indicator light DETAILED DESCRIPTION

[0040] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] Figure 1 It is a schematic diagram of the overall structure of the present invention, including a display panel layer, an upper circuit board, a lower circuit board, input and output ports of the circuit to be tested, upper and lower circuit connection terminals, and a relay module. The port of the circuit to be tested on the left side of the figure is an input port, and the port on the right side is an output port. The device as a whole is connected in series in the circuit to be tested, which will not affect the operation of the circuit to be tested. The power supply circuit is designed to be self-powered, and no external power supply is required. It will directly draw power from the circuit to be tested. The power-drawing current is at the 10mA level, and the current is very small, which will not increase the workload of the circuit to be tested. After connecting to the circuit to be tested, the device will automatically turn on, and can interact with the system through buttons or external communication modules, set restriction rules and circuit on-off operations, and realize automatic control and real-time monitoring.

[0042] Figure 2 A schematic diagram of the front structure of the upper and lower circuits of the present invention is given. Figure 3 A schematic diagram of the reverse structure is given. Figure 2 and Figure 3 The digital circuit elements of the present invention are concentrated in the upper circuit layer (17), and the analog circuits related to the circuit to be tested and the sampling circuit are concentrated in the lower circuit layer (18); the single-chip microcomputer chip (8), the step-down circuit (12), the voltage sampling circuit (13), the current sampling circuit (15), the relay (6) and the control circuit thereof realize the basic functions of automatic control and real-time monitoring.

[0043] The single-chip microcomputer chip (8) needs to be a model with ADC sampling function, USART communication function and basic GPIO input and output function. It also needs to have a higher main frequency to reduce the response delay, which helps to cut off or open the circuit in time.

[0044] The button (2) is a touch button type. When pressed, the circuit is closed, and when released, the circuit is disconnected. At the same time, the button needs to be connected to a parallel capacitor filter to prevent key jitter.

[0045] The relay module (6) should use a contact withstanding current higher than a certain value of the possible current of the circuit to be tested, and the coil working voltage should be the voltage that can be obtained in the step-down circuit. In this embodiment, a 5V working voltage is used.

[0046] The upper and lower circuit connection terminals (1-1, 1-2) connect the upper and lower GND circuits, which stabilizes the potential difference. At the same time, the 5V and 3.3V operating voltages of the upper layer are provided to the lower layer, and the voltage of the circuit to be tested and the sampling voltage of the lower layer are fed back to the upper layer.

[0047] The communication circuit interface (3, 10) is connected to the USART function pin of the single-chip microcomputer chip, and after the external communication module is correctly inserted, power monitoring information can be obtained in real time, and control instructions can be used for control.

[0048] The external display screen (4-1) needs to have pins that match the screen FPC terminals (4-3), and use the screen FPC vias (4-2) for routing. After correct connection, the device working status can be obtained from the screen.

[0049] The input and output ports (5-1, 5-2) of the circuit to be tested need to be connected in a standardized manner to avoid reverse connection problems. Reverse connection may cause abnormal working status. The port model can be changed according to the actual situation.

[0050] In this embodiment, current sampling is performed through a current sampling circuit (15), and the current sampling chip uses a current Hall sensor, which is welded on the back of the lower circuit board (18). At the same time, a long opening is made on the lower circuit board to reduce induced current interference.

[0051] When the power of the circuit to be tested is expected to be high, the circuit wire needs to be expanded. The specific treatment method is: expose the wire through which the current to be tested passes, and cover it with a solder layer to increase the cross-sectional area of ​​the current, reduce the wire resistance, thereby reducing the heat generation phenomenon and increasing the current that can pass.

[0052] The present invention adopts a multi-stage buck design to provide different voltages to modules with different requirements, thereby improving the flexibility and scalability of the present invention. The specification of the buck chip in the buck circuit (12) can be adjusted according to the voltage of the circuit to be tested. In this embodiment, the specification of the first-stage buck chip is an input of 4.5-40V and a maximum current of 3A, and the specification of the second-stage buck chip is an input of 5V, an output of 3.3V, and a maximum current of 0.5A.

[0053] The voltage sampling circuit (13) uses an operational amplifier for isolation and voltage regulation to ensure that the collected voltage value is not distorted by interference from the sampling operation itself.

[0054] The crystal oscillator (14) circuit needs to be selected according to the model of the selected single-chip microcomputer chip, and the clock frequency and the frequency division ratio need to be synchronously set in the register of the single-chip microcomputer. In this embodiment, an 8kHZ passive crystal oscillator and a 22pF coupling capacitor are selected.

[0055] The screen boost circuit (11) should be selected with appropriate specifications according to the external display screen used, especially the output value of the boost circuit should be the same as the input voltage parameter value of the external display screen.

[0056] The key dimensions of the invention are: length 57mm, width 25mm, height 29mm, volume 0.00004m 3 , applicable voltage range is 5~40V, applicable current range is 0~35A, maximum power handling is 1400W, achieving small size, high integration, and high range. At the same time, it can be connected through the communication circuit interface and external communication module for real-time monitoring and control settings, with high flexibility.

[0057] The circuit automatic control and power monitoring device prototype designed by the present invention adopts a two-stage step-down circuit and a double-layer structure, with a maximum power tolerance of 1400W and a volume of only 0.00004m 3 . In order to ensure the safe and stable operation of the device in such a small volume, the present invention has carried out a design of covering the exposed wire with a solder layer and isolating the analog and digital circuits, which has low cost and significant effect. After testing, the prototype designed by the present invention can work continuously for several hours without generating obvious heat. At the same time, the overall device can also replace the specifications of the measurement module according to the specific situation of the circuit to be tested, forming a monitoring device with different ranges and accuracies, achieving low cost, high flexibility, and high reliability, and can be applied to a wider range of measurement occasions.

[0058] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they are aware of the basic creative concepts. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0059] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A circuit automatic control and power monitoring device, characterized in that: It comprises a single-chip microcomputer chip (8), the single-chip microcomputer chip (8) being integrated with a voltage-reducing circuit (12), a voltage sampling circuit (13), a current sampling circuit (15), and a crystal oscillator circuit (14), and being used for real-time monitoring of the power of the circuit to be tested and automatically controlling the on / off of the circuit to be tested through a relay module (6) and its control circuit; The relay module (6) is connected in series between the positive terminal of the input port (5-1) of the circuit to be tested and the positive terminal of the output port (5-2) of the circuit to be tested, and is connected to the single-chip microcomputer chip (8) via a relay control circuit; The relay control circuit is composed of a transistor, a Schottky diode and necessary resistors, the base of the transistor is connected to the control pin of the single-chip microcomputer chip, and the single-chip microcomputer chip (8) can control the closing and opening of the relay; The current sampling circuit (15) is connected in series between the negative terminal of the input port (5-1) of the circuit to be tested and the negative terminal of the output port (5-2) of the circuit to be tested, and is connected to the ADC input pin of the single-chip microcomputer chip (8) after being processed by the operational amplifier circuit.

2. A circuit automatic control and power monitoring device as claimed in claim 1, characterized in that: The circuit board has a double-layer structure, which is divided into an upper circuit layer (17) and a lower circuit layer (18), wherein the upper circuit layer (17) integrates a digital circuit part, and the lower circuit layer (18) integrates an analog circuit part and a part through which current flows in the circuit to be tested; The upper circuit layer (17) and a part of the circuit in the lower circuit layer (17) of the circuit automatic control and power monitoring device are connected via upper and lower circuit connection terminals (1-1, 1-2); The circuit automatic control and power monitoring device has an applicable voltage range of 5-40V, an applicable current range of 0-35A, a maximum power bearing capacity of 1400W, a length of 57mm, a width of 25mm, a height of 29mm, and a volume of 0.00004m 3 .

3. A circuit automatic control and power monitoring device as claimed in claim 2, characterized in that: The upper circuit layer (17), the lower circuit layer (18) and the display panel layer (7) are fixed via four M2 through holes (16) located at the four corners of each layer; the display panel layer (7) is located directly above the upper circuit layer (17), and the screen (4-1) and indicator light area (19) corresponding to the upper circuit layer (17) are made transparent.

4. A circuit automatic control and power monitoring device as claimed in claim 1, characterized in that: When working, the circuit to be tested is connected in series, the positive part of the circuit to be tested is connected in series with the positive end of the input and output terminals (5-1, 5-2) of the circuit to be tested, and the negative part of the circuit to be tested is connected in series with the negative end of the input and output terminals (5-1, 5-2) of the circuit to be tested; The circuit board wires between the input end and the output end of the positive terminal and the negative terminal of the circuit to be tested are exposed without oil covering and covered with a solder layer.

5. A circuit automatic control and power monitoring device as claimed in claim 1, characterized in that: The pins of the single-chip microcomputer chip (8) are connected to a step-down circuit (12). The step-down circuit (12) adopts a two-stage step-down structure. The first-stage step-down circuit is connected to the circuit to be tested, and reduces the voltage of the circuit to be tested to 5V, thereby supplying power to the relay module (6), the voltage sampling circuit (13) and the current sampling circuit (15). Subsequently, the second-stage step-down circuit reduces the 5V to 3.3V, thereby supplying power to the single-chip microcomputer chip (8), the screen FPC terminal (4-3), the communication circuit interface (10), the key circuit (3) and the relay control circuit.

6. A circuit automatic control and power monitoring device as claimed in claim 1, characterized in that: The communication pin of the single-chip microcomputer chip (8) and the communication circuit interface (10) are connected to the screen FPC terminal (4-3); The communication circuit interface (10) and the screen FPC terminal (4-3) are both pluggable structures, and the external communication module and the external display screen (4-1) connected thereto can be replaced at any time according to specific needs.

7. A circuit automatic control and power monitoring device as claimed in claim 1, characterized in that: The control pin of the single-chip microcomputer chip (8) is connected to the indicator light (19) circuit to control the on and off of the indicator light.

8. The circuit automatic control and power monitoring device according to claim 1, characterized in that: The input pin of the single-chip microcomputer chip (8) is connected to the key (2) circuit, allowing the user to input corresponding instructions by pressing the key.

9. A circuit automatic control and power monitoring device as claimed in claim 1, characterized in that: The communication pin of the single-chip microcomputer chip (8) is connected to the communication pin of the screen FPC terminal (4-3), and communicates with the display screen through a communication protocol such as SPI, thereby realizing light control and content display of the external display screen (4-1); The power pin of the screen FPC terminal (4-3) is connected to the screen boost circuit (11) to boost 3.3V to the voltage required for screen operation; The external display screen (4-1) is fixed on the front side of the upper circuit board (17) and is located between the upper circuit board (17) and the display panel (7); its FPC cable passes through the screen FPC cable via hole (4-2) and is connected to the FPC terminal (4-3) on the back side of the upper circuit board.

10. A circuit automatic control and power monitoring device design method, characterized in that: The design method is used to design a circuit automatic control and power monitoring device according to any one of claims 1 to 9, comprising the following steps: Determining the specifications of the step-down chip and the relay (6) in the step-down circuit (12) according to the possible current and voltage range of the circuit to be tested; Determine the size of the lower circuit board (18) and the distance between the upper and lower circuit boards according to the package size of the relay (6); Determine the circuit board conductor processing method between the input terminal (5-1) and the output terminal (5-2) of the circuit to be tested according to the current size of the circuit to be tested and the continuous working time, so as to ensure the safe passage of current; Determining the pin sequence of the communication circuit interface (10) and the screen FPC terminal (4-3) according to the pin sequence of the external communication module and the external display screen (4-1); Determining the voltage boosting size of the voltage boosting circuit (11) according to the voltage characteristics of the external display screen (4-1); Determining the amplification ratio of the operational amplifier in the voltage and current sampling circuit (13, 15) according to the possible voltage and current range of the circuit to be tested; According to the size and layout of the upper circuit layer (17) and the lower circuit layer (18), the upper and lower circuit connection terminals (1-1, 1-2) are used for connection and fixed through the through holes (16) at the four corners.

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