Multifunctional compatible input signal processing circuit
Through the multi-function compatible input signal processing circuit of integrated input protection, signal conditioning and switch control modules, the problems of high hardware cost and complex structure in traditional circuit design are solved, and efficient signal processing and circuit simplification are achieved.
Patent Information
- Application Number
- CN202422369478.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-27
- Publication Date
- 2025-07-11
- Estimated Expiration
- 2034-09-27
AI Technical Summary
Traditional circuit design requires individual ports and signal processing circuits for each input signal type, resulting in high hardware costs, complex circuit structures and difficult maintenance.
It adopts a multi-function compatible input signal processing circuit, including input protection module, signal conditioning module and switch control module, and integrates bidirectional TVS diodes, field effect tubes, resistors, filter capacitors and limiting diodes to achieve signal protection, conditioning and switching, and control signal paths through a microcontroller.
It reduces hardware costs, simplifies circuit structure, improves system maintainability and scalability, and can be seamlessly compatible with multiple input signal types.
Smart Images
Figure CN223092326U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of signal processing, in particular to a multifunctional compatible input signal processing circuit. Background Art
[0002] In industrial automation and control systems, products often need to receive various types of input signals, such as 0 - 5V, 0 - 10V voltage signals, and 4 - 20mA current signals, to achieve precise control of different devices and sensors. However, when traditional circuit designs process these diverse input signals, they often need to separately design input ports and corresponding signal processing circuits for each signal type. This not only increases the hardware cost but also complicates the circuit structure, increasing the difficulty of wiring and maintenance. Summary of the Invention
[0003] In view of this, the purpose of the utility model is to provide a multifunctional compatible input signal processing circuit that reduces hardware costs, saves ports, and has a simple circuit.
[0004] To achieve the above purpose, the utility model adopts such a multifunctional compatible input signal processing circuit, which includes an input protection module, a signal conditioning module, a switch control module, a digital output port AD_MNL, and a single-chip microcomputer. The input end of the input protection module receives external input signals and is used to protect the subsequent circuit when the circuit is subjected to transient overvoltage impact. The input end of the switch control module is connected to the output end of the input protection module and is used to adjust the signal path according to the control signal sent by the single-chip microcomputer. The input end of the signal conditioning module is connected to the output end of the switch control module and is used to preprocess the signal from the switch control module. The digital output port AD_MNL is connected between the signal conditioning module and the single-chip microcomputer and is used to transmit the conditioned signal to the single-chip microcomputer for ADC conversion. The single-chip microcomputer is used to control the switch control module and perform corresponding operations according to the signal received by AD_MNL.
[0005] The utility model is further provided that the input protection module includes at least two bidirectional TVS diodes, and the bidirectional TVS diodes are connected in parallel between the external input signal and the ground and are used to quickly conduct when the circuit is subjected to transient overvoltage and divert the overvoltage energy to the ground.
[0006] The utility model is further provided that the switch control module includes at least two field effect transistors, a digital output port SEL_DL, and a digital output port SEL_DY10. The field effect transistors are used to control the on-off state of the signal path according to the control signal sent by the single-chip microcomputer through the digital output port. The digital output port SEL_DL is used to control the on-off state of the first field effect transistor, and the digital output port SEL_DY10 is used to control the on-off state of the second field effect transistor.
[0007] This utility model is further configured such that the signal conditioning module includes four resistors, two filter capacitors, and a clamping diode. The resistors are used for voltage division or impedance matching. The filter capacitors are used to filter out high-frequency noise and interference in the signal. The clamping diode is used to limit the maximum amplitude of the signal.
[0008] Compared with the prior art, the beneficial effects of this utility model are as follows: Through a highly integrated design, the number and types of required components are significantly reduced, thereby greatly reducing the overall hardware cost. Its built-in flexible signal switching and fine conditioning mechanism enable the circuit to cleverly utilize a limited number of ports to seamlessly compatible with and process various types of input signals. In addition, through a modular design, functions such as input protection, signal conditioning, and switch control are integrated into a single circuit, which not only simplifies the complex circuit structure but also greatly improves the maintainability and expandability of the system. BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Figure 1 is the circuit schematic diagram of the embodiment of this utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0010] As Figure 1 shown, the embodiment of this utility model provides a multi-functional compatible input signal processing circuit, including an input protection module, a signal conditioning module, a switch control module, a digital output port AD_MNL, and a single-chip microcomputer. The input end of the input protection module receives an external input signal and is used to protect the subsequent circuit when the circuit is subjected to a transient overvoltage impact. The input end of the switch control module is connected to the output end of the input protection module and is used to adjust the signal path according to the control signal sent by the single-chip microcomputer. The input end of the signal conditioning module is connected to the output end of the switch control module and is used to preprocess the signal from the switch control module. The digital output port AD_MNL is connected between the signal conditioning module and the single-chip microcomputer and is used to transmit the conditioned signal to the single-chip microcomputer for ADC conversion. The single-chip microcomputer is used to control the switch control module and perform corresponding operations according to the signal received by AD_MNL.
[0011] The input protection module consists of a bidirectional TVS diode DR1 and a bidirectional TVS diode DR2. The two bidirectional TVS diodes are connected in parallel between the external input signal and the ground and are used to quickly conduct when the circuit is subjected to a transient overvoltage and divert the overvoltage energy to the ground.
[0012] The switch control module consists of field effect transistor Q1, field effect transistor Q2, digital output port SEL_DL, and digital output port SEL_DY10. Both field effect transistors are used to control the on / off state of the signal path according to the control signals sent by the single-chip microcomputer through the digital output ports. The digital output port SEL_DL is used to control the on / off state of field effect transistor Q1, and the digital output port SEL_DY10 is used to control the on / off state of field effect transistor Q2.
[0013] The signal conditioning module consists of resistors R1 - R4, filter capacitors C1 - C2, and clamping diode Q3. Resistors R1 - R4 are used for voltage division or impedance matching so that signals can be correctly transmitted and received. Filter capacitors C1 - C2 are used to filter out high-frequency noise and interference in the signals and improve the signal purity. The clamping diode Q3 consists of two diodes connected in reverse parallel and includes a common terminal, which is used to limit the maximum amplitude of the signal and protect the subsequent circuit from damage.
[0014] Specifically, one end of the bidirectional TVS diode DR2 is respectively connected to the external input signal terminal EX_MNL, one end of the filter capacitor C1, one end of the resistor R3, one end of the bidirectional TVS diode DR1, and one end of the resistor R1. The other end of the resistor R3 is respectively connected to the other end of the bidirectional TVS diode DR1 and the drain of the field effect transistor Q1. The gate of the field effect transistor Q1 is connected to the digital output port SEL_DL, and the digital output port SEL_DL is connected to the single-chip microcomputer. The other end of the resistor R1 is respectively connected to one end of the resistor R2, one end of the resistor R4, one end of the filter capacitor C2, and the common terminal of the clamping diode Q3. The common terminal of the clamping diode Q3 is also connected to the digital output port AD_MNL, and the digital output port AD_MNL is connected to the single-chip microcomputer. The other end of the resistor R2 is connected to the drain of the field effect transistor Q2. The gate of the field effect transistor Q2 is connected to the digital output port SEL_DY10, and the digital output port SEL_DY10 is connected to the single-chip microcomputer. The other end of the bidirectional TVS diode DR2, the other end of the filter capacitor C1, the source of the field effect transistor Q1, the source of the field effect transistor Q2, the other end of the resistor R4, the other end of the filter capacitor C2, and the non-common terminal of the positive side of the clamping diode Q3 are all grounded. The non-common terminal of the negative side of the clamping diode Q3 is connected to the power supply +3.3V.
[0015] Working principle of the utility model: In the 0 - 5V input control mode, the single-chip microcomputer does not send control signals to the digital output port SEL_DL and the digital output port SEL_DY10, making the field-effect transistors Q1 and Q2 both in the cut-off state. At this time, the signal path mainly divides the voltage through the resistors R1 and R4. When the external input signal EX_MNL varies within the range of 0 - 5V, due to the voltage division effect of the resistor R4 and the resistors R1 and R2 (but the resistor R2 is disconnected due to the cut-off of the field-effect transistor Q2), the voltage obtained at the digital output port AD_MNL will vary within the range of 0 - 2.5V. The single-chip microcomputer converts this voltage value through ADC to identify the externally input analog signal.
[0016] In the 0 - 10V input control mode, the single-chip microcomputer sends a high-level signal to the digital output port SEL_DY10, making the field-effect transistor Q2 conduct, while the field-effect transistor Q1 remains in the cut-off state. At this time, the resistor R2 is connected to the circuit and is in parallel with the resistor R4, forming a new voltage division network. The equivalent resistance of this parallel network is lower than the resistance of the resistor R4 alone, enabling the voltage at the digital output port AD_MNL to still vary within the range of 0 - 2.5V within the input range of 0 - 10V. In this way, the single-chip microcomputer can identify the input signal of 0 - 10V through ADC conversion.
[0017] In the 4 - 20mA current input control mode, the single-chip microcomputer sends a high-level signal to the digital output port SEL_DL, making the field-effect transistor Q1 conduct, while the field-effect transistor Q2 remains in the cut-off state. At this time, the resistor R3 is connected to the circuit as a current-to-voltage conversion resistor. When the external input signal EX_MNL port provides a current of 4 - 20mA, this current generates a corresponding voltage drop through the resistor R3, thereby obtaining a voltage within the range of 0.5 - 2.5V at the digital output port AD_MNL. The single-chip microcomputer converts this voltage value through ADC to identify the 4 - 20mA current input.
[0018] Of course, in addition to the above embodiments, the utility model can also have many other embodiments. Without departing from the substantial technical solution content of the utility model, those skilled in the art can make various corresponding changes and deformations according to the utility model. And if these changes or deformations are equivalent to the technical solutions in this patent, then these corresponding changes and deformations should all fall within the protection scope of the appended claims of the utility model, and this utility model creation meets the actual R & D capabilities and resource conditions of the applicant.
Claims
1. A multi-functional compatible input signal processing circuit, characterized in that: It includes an input protection module, a signal conditioning module, a switch control module, a digital output port AD_MNL, and a single-chip microcomputer. The input end of the input protection module receives an external input signal and is used to protect the subsequent circuit when the circuit is subjected to a transient overvoltage impact. The input end of the switch control module is connected to the output end of the input protection module and is used to adjust the signal path according to the control signal sent by the single-chip microcomputer. The input end of the signal conditioning module is connected to the output end of the switch control module and is used to preprocess the signal from the switch control module. The digital output port AD_MNL is connected between the signal conditioning module and the single-chip microcomputer and is used to transmit the conditioned signal to the single-chip microcomputer for ADC conversion. The single-chip microcomputer is used to control the switch control module and perform corresponding operations according to the signal received by AD_MNL.
2. The multifunctional compatible input signal processing circuit according to claim 1, wherein: The input protection module includes at least two bidirectional TVS diodes. The bidirectional TVS diodes are connected in parallel between the external input signal and the ground and are used to quickly conduct when the circuit is subjected to a transient overvoltage and divert the overvoltage energy to the ground.
3. The multifunctional compatible input signal processing circuit according to claim 1 or 2, characterized in that: The switch control module includes at least two field effect transistors, a digital output port SEL_DL, and a digital output port SEL_DY10. The field effect transistors are used to control the on-off state of the signal path according to the control signal sent by the single-chip microcomputer through the digital output port. The digital output port SEL_DL is used to control the on-off state of the first field effect transistor. The digital output port SEL_DY10 is used to control the on-off state of the second field effect transistor.
4. The multifunctional compatible input signal processing circuit according to claim 3, wherein: The signal conditioning module includes four resistors, two filter capacitors, and a limiting diode. The resistors are used for voltage division or impedance matching. The filter capacitors are used to filter out high-frequency noise and interference in the signal. The limiting diode is used to limit the maximum amplitude of the signal.