Wide voltage switching value acquisition circuit

Abstract

The utility model discloses a wide voltage switching value acquisition circuit, which relates to the technical field of industrial automation control, and comprises a voltage stabilizing diode, a voltage dividing network, a triode, a pull-up resistor, a current limiting resistor and a microcontroller port which are connected in series, the voltage dividing network is used for obtaining divided voltage; the triode comprises a base, an emitter and a collector; a base electrode is connected with a connection point A of the first divider resistor and the second divider resistor and is used for receiving the divided voltage, an emitter electrode is grounded, and a collector electrode is used for limiting the current flowing into the port of the microcontroller within a safe range; and the microcontroller port is used for acquiring the wide voltage switching value based on the low level signal or the high level signal, so that the problems that the switching value signal is difficult to stably acquire in a wide input voltage range and the microcontroller port is easy to damage due to overlarge current in the prior art can be solved.

Description

Technical Field

[0001] This utility model relates to the field of industrial automation control technology, and in particular to a wide voltage switching quantity acquisition circuit. Background Technology

[0002] In many fields such as industrial automation, smart homes, and power systems, switch signal acquisition is a key step in obtaining equipment status information.

[0003] However, existing digital input signal acquisition circuits have many shortcomings. Traditional acquisition circuits can usually only adapt to a specific narrow voltage range. When the input voltage exceeds its rated range, the circuit cannot work properly and may even damage components, severely limiting its application in different power supply environments. Moreover, in complex electromagnetic environments, external interference can easily cause deviations in the acquired digital input signals, leading to incorrect judgments and controls by the system.

[0004] In addition, the existing circuit's protection mechanism for the back-end microcontroller port is not perfect. Excessive current may damage the microcontroller port, increasing the system's maintenance costs and failure risks.

[0005] Therefore, there is an urgent need for a circuit that can adapt to a wide voltage input range, accurately acquire switching signals, and effectively protect the microcontroller ports. Utility Model Content

[0006] In view of this, the present invention proposes a wide voltage switching signal acquisition circuit, which can realize wide voltage stable input, accurate acquisition of switching signals, and effective protection of microcontroller ports.

[0007] To achieve the above objectives, this utility model provides the following technical solution:

[0008] A wide-voltage switching signal acquisition circuit includes a series-connected Zener diode, a voltage divider network, a transistor, a pull-up resistor, a current-limiting resistor, and a microcontroller port. The voltage divider network includes a first voltage divider resistor and a second voltage divider resistor.

[0009] The cathode of the Zener diode is connected to the positive terminal of the external power supply, and the anode of the Zener diode is connected to the first voltage divider resistor. This is used to regulate the input voltage from the external power supply to obtain a regulated voltage.

[0010] The voltage divider network is used to divide the regulated voltage to obtain a divided voltage;

[0011] The transistor includes a base, an emitter, and a collector;

[0012] The base is connected to the connection point A of the first voltage divider resistor and the second voltage divider resistor to receive the voltage divider voltage. The emitter is grounded. The collector is pulled up by a pull-up resistor and then connected to the microcontroller port through a current-limiting resistor to limit the current flowing into the microcontroller port within a safe range.

[0013] The transistor is turned on or off according to the voltage divider. When the transistor is on, a path is formed between the collector and the emitter, and the microcontroller port receives a low-level signal. When the transistor is off, an open circuit is formed between the collector and the emitter, and the collector is connected to the power supply through a pull-up resistor, and the microcontroller port receives a high-level signal.

[0014] The microcontroller port is used to acquire wide-range voltage switching quantities based on the low-level signal or the high-level signal.

[0015] Based on the above technical solution, the present invention can be further improved as follows:

[0016] Optionally, the input voltage is a wide voltage range of 8V-40V.

[0017] Optionally, the Zener diode is further used for:

[0018] Determine whether the input voltage exceeds the preset regulated voltage value. If so, enter the reverse breakdown state and stabilize the input voltage at the preset regulated voltage value.

[0019] Optionally, the breakdown voltage of the Zener diode is 8.2V±5% to ensure that the voltage drop across connection point A is stable at 4.1V±5%.

[0020] Optionally, the maximum power consumption of the Zener diode is 500mW.

[0021] Optionally, the voltage divider network is further used for:

[0022] Calculate the voltage divider using formula (1);

[0023]

[0024] In the formula, is the voltage divider, is the regulated voltage, is the resistance value of the first voltage divider resistor, and is the resistance value of the second voltage divider resistor;

[0025] By adjusting the resistance ratio of and , different voltage dividers can be obtained.

[0026] Optionally, the first and second voltage divider resistors are 1% precision resistors with a temperature coefficient ≤50ppm / ℃.

[0027] Optionally, the transistor is also used for:

[0028] When the voltage divider creates a preset bias voltage between the base and emitter, the transistor turns on, the emitter is grounded, and the collector is pulled up to the 3.3V power supply through a pull-up resistor.

[0029] Optionally, the transistor is also used for:

[0030] When a base input signal is generated, the base current is produced. Based on the transistor's current amplification factor, the base input signal is amplified.

[0031] Calculate the collector current using formula (2);

[0032] I C =β×I B Formula (2);

[0033] In the formula, is the collector current, is the transistor current amplification factor, and is the base current.

[0034] Optionally, the safety range is 0mA-3.3mA.

[0035] This utility model has the following advantages:

[0036] This utility model presents a medium-range voltage switching quantity acquisition circuit. Through a combination of a Zener diode and a voltage divider network, it achieves stable voltage reduction and division for input voltages ranging from 8-40V, breaking through the voltage limitations of traditional circuits and greatly expanding application scenarios. Utilizing the conduction and cutoff characteristics of transistors, it accurately converts switching states into high and low level signals, ensuring stable and accurate acquisition of switching quantities by the microcontroller and avoiding signal distortion. Pull-up resistors and current-limiting resistors work together to limit the current flowing into the microcontroller port within a safe range, effectively preventing damage to the port due to excessive current and improving circuit reliability and lifespan. Furthermore, this utility model's medium-range voltage switching quantity acquisition circuit uses common electronic components, resulting in a simple structure that reduces development costs and maintenance difficulty while ensuring high performance, facilitating large-scale application. Attached Figure Description

[0037] For illustrative and not limiting purposes, the present invention will now be described in conjunction with embodiments and accompanying drawings, wherein:

[0038] Figure 1 This is a schematic diagram of the wide voltage switching quantity acquisition circuit in the embodiment of this utility model. Detailed Implementation

[0039] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort should fall within the scope of protection of the present invention.

[0040] It should be noted that the terms "first," "second," etc., in the specification and accompanying drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this utility model described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0041] It should be noted that, where there is no conflict, the embodiments of this utility model and the features thereof can be combined with each other. The embodiments of this utility model will now be described in detail with reference to the accompanying drawings.

[0042] Figure 1 This is a schematic diagram of the main components of the wide-voltage switching quantity acquisition circuit in an embodiment of this utility model. (See diagram below.) Figure 1 As shown, the wide voltage switching quantity acquisition circuit 1 provided in this embodiment of the present invention includes a series-connected Zener diode 10, a voltage divider network 20, a transistor 30, a pull-up resistor 40, a current-limiting resistor 50, and a microcontroller port 60. The voltage divider network includes a first voltage divider resistor 201 and a second voltage divider resistor 202.

[0043] This wide-voltage switching signal acquisition circuit is mainly used to accurately acquire switching signals in a wide voltage input environment of 8V-40V and convert them into high and low level signals that can be recognized by a microcontroller. Through the coordinated work of the components in the circuit, it ensures that the switching signal acquisition task can be completed stably and reliably under different input voltage conditions.

[0044] Zener diode 10 has its cathode connected to the positive terminal of the external power supply and its anode connected to the first voltage divider resistor 201. Its main function is to regulate the input voltage from 8V to 40V. When the input voltage exceeds the preset regulated value (8.2V ± 5%), it enters reverse breakdown mode, stabilizing the input voltage at the preset regulated value and ensuring that subsequent circuits operate under a stable voltage environment. The maximum power dissipation of Zener diode 10 is 500 kΩ. m The W parameter limit ensures that the Zener diode 10 will not be damaged by excessive power during normal operation.

[0045] The voltage divider network 20 consists of a first voltage divider resistor 201 and a second voltage divider resistor 202, used to divide the regulated voltage output by the Zener diode 10 to obtain a divided voltage. The divided voltage is calculated using formula (1).

[0046]

[0047] In the formula, U is the voltage divider voltage, U total For the regulated voltage, R1 is the resistance value of the first voltage divider resistor 201, and R2 is the resistance value of the second voltage divider resistor 202;

[0048] The first voltage divider resistor 201 and the second voltage divider resistor 202 are 1% precision resistors with a temperature coefficient ≤50ppm / ℃. This ensures the accuracy and stability of the voltage divider and minimizes the impact of temperature and other factors. Furthermore, by adjusting the resistance ratio of R1 and R2, different voltage dividers can be obtained to meet various circuit requirements.

[0049] The base of transistor 30 is connected to the junction point A of the first voltage divider resistor 201 and the second voltage divider resistor 202, receiving the divided voltage. When the divided voltage creates a preset bias voltage between the base and emitter, transistor 30 conducts, forming a path between the collector and emitter, and the microcontroller port 60 receives a low-level signal; when the divided voltage is insufficient to form the preset bias voltage, transistor 30 is cut off, creating an open circuit between the collector and emitter, and the collector is connected to the 3.3V power supply through the pull-up resistor 40, and the microcontroller port 60 receives a high-level signal.

[0050] When a base input signal is generated, the base current is produced. Based on the current amplification factor β of the transistor, the base input signal is amplified.

[0051] Calculate the collector current using formula (2);

[0052] I C =β×I B Formula (2);

[0053] In the formula, I C I is the collector current, β is the current amplification factor of the transistor, and I is the collector current.B This is the base current.

[0054] Pull-up resistor 40: Pulls up the collector of transistor 30 to the 3.3V power supply, ensuring that the collector outputs a high-level signal when transistor 30 is cut off.

[0055] Current limiting resistor 50: Connected between the collector and the microcontroller port 60, it limits the current flowing into the microcontroller port 60 to a safe range of 0mA-3.3mA to prevent excessive current from damaging the microcontroller port 60.

[0056] Microcontroller port 60: Based on the received high and low level signals, it acquires wide voltage switching quantities to provide a basis for subsequent control and processing.

[0057] The signal processing procedure of this wide voltage switching signal acquisition circuit is as follows:

[0058] An external wide voltage of 8V-40V is input into the circuit. It is first regulated by Zener diode 10 to stabilize the voltage at 8.2V±5%.

[0059] The regulated voltage enters the voltage divider network 20, and is divided by the first voltage divider resistor 201 and the second voltage divider resistor 202 to obtain the divided voltage.

[0060] A voltage divider is input to the base of transistor 30 to control its on or off state. When transistor 30 is on, microcontroller port 60 receives a low-level signal; when transistor 30 is off, microcontroller port 60 receives a high-level signal.

[0061] The microcontroller port 60 acquires wide-voltage switching signals based on the received high and low level signals.

[0062] In summary, this wide-voltage switching quantity acquisition circuit, through the coordinated operation of its components, achieves accurate acquisition of switching quantities under wide voltage input conditions, while ensuring the stability and reliability of the circuit and protecting the microcontroller port 60 from damage.

[0063] One embodiment is as follows:

[0064] When the input is 24V: the Zener diode limits the 24V input voltage to 8.2V, and after being divided by the voltage divider network composed of R1 and R2, a voltage of 4.1V is obtained. This voltage turns on the transistor, and the collector voltage is approximately 0.3V, which is a low-level state, representing a switching state.

[0065] When the input is 40V: the Zener diode still maintains the voltage at 8.2V, and after voltage division, it is still 4.1V, ensuring that the output voltage is stable at a low level, which shows the stability of the circuit output under different high input voltages.

[0066] Table 1

[0067]

[0068] As shown in Table 1, the measured waveforms at the microcontroller port are as follows: the rise time is no more than 10ns, indicating that the signal rises quickly; the pulse width distortion rate is less than 2%, which means that the signal is not distorted during transmission, ensuring the accuracy and reliability of the signal.

[0069] Performance under different input voltages: With an input of 8V, the output level is 3.12V and the power consumption is 0.64mW; with an input of 24V, the output level is 0.28V and the power consumption is 2.15mW; with an input of 40V, the output level is 0.27V and the power consumption is 3.89mW. This demonstrates the circuit's output level and power consumption under different input voltages, indicating that the circuit can adapt to a wide voltage input range while maintaining a reasonable power consumption.

[0070] The specific embodiments described above do not constitute a limitation on the scope of protection of this utility model. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can occur depending on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. A wide-voltage switching quantity acquisition circuit, characterized in that, It includes a series-connected Zener diode, a voltage divider network, a transistor, a pull-up resistor, a current-limiting resistor, and a microcontroller port. The voltage divider network includes a first voltage divider resistor and a second voltage divider resistor. The cathode of the Zener diode is connected to the positive terminal of the external power supply, and the anode of the Zener diode is connected to the first voltage divider resistor. This is used to regulate the input voltage from the external power supply to obtain a regulated voltage. The voltage divider network is used to divide the regulated voltage to obtain a divided voltage; The transistor includes a base, an emitter, and a collector; The base is connected to the connection point A of the first voltage divider resistor and the second voltage divider resistor to receive the voltage divider voltage. The emitter is grounded. The collector is pulled up by a pull-up resistor and then connected to the microcontroller port through a current-limiting resistor to limit the current flowing into the microcontroller port within a safe range. The transistor is turned on or off according to the voltage divider. When the transistor is on, a path is formed between the collector and the emitter, and the microcontroller port receives a low-level signal. When the transistor is off, an open circuit is formed between the collector and the emitter, and the collector is connected to the power supply through a pull-up resistor, and the microcontroller port receives a high-level signal. The microcontroller port is used to acquire wide-range voltage switching quantities based on the low-level signal or the high-level signal.

2. The wide voltage switching quantity acquisition circuit according to claim 1, characterized in that, The input voltage is a wide voltage range of 8V-40V.

3. The wide voltage switching quantity acquisition circuit according to claim 1, characterized in that, The Zener diode is also used for: Determine whether the input voltage exceeds the preset regulated voltage value. If so, enter the reverse breakdown state and stabilize the input voltage at the preset regulated voltage value.

4. The wide voltage switching quantity acquisition circuit according to claim 1, characterized in that, The breakdown voltage of the Zener diode is 8.2V±5% to ensure that the voltage drop across connection point A is stable at 4.1V±5%.

5. The wide voltage switching quantity acquisition circuit according to claim 1, characterized in that, The maximum power consumption of the Zener diode is 500mW.

6. The wide voltage switching quantity acquisition circuit according to claim 1, characterized in that, The voltage divider network is also used for: Calculate the voltage divider using formula (1); In the formula, U is the voltage divider voltage, U total For the regulated voltage, R1 is the resistance value of the first voltage divider resistor, and R2 is the resistance value of the second voltage divider resistor; By adjusting the resistance ratio of R1 and R2, different voltage dividers can be obtained.

7. The wide voltage switching quantity acquisition circuit according to claim 1, characterized in that, The first and second voltage divider resistors are 1% precision resistors with a temperature coefficient ≤50ppm / ℃.

8. The wide voltage switching quantity acquisition circuit according to claim 1, characterized in that, The transistor is also used for: When the voltage divider creates a preset bias voltage between the base and emitter, the transistor turns on, the emitter is grounded, and the collector is pulled up to the 3.3V power supply through a pull-up resistor.

9. The wide voltage switching quantity acquisition circuit according to claim 1, characterized in that, The transistor is also used for: When a base input signal is generated, the base current is produced. Based on the transistor current amplification factor β, the base input signal is amplified. Calculate the collector current using formula (2); I C =β×I B Formula (2); In the formula, I C I is the collector current, β is the transistor current amplification factor, and I is the collector current. B This is the base current.

10. The wide voltage switching quantity acquisition circuit according to claim 1, characterized in that, The safe range is 0mA-3.3mA.

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