Current pulse modulation identification circuit

Abstract

The embodiment of the present application discloses a current pulse modulation identification circuit. The current pulse modulation identification circuit comprises a protection module, a conversion module, a diagnosis module and a processing module; the protection module is used for receiving a current pulse signal and protecting the conversion module, the diagnosis module and the processing module; the protection module is connected with the conversion module, and the conversion module is used for converting the current pulse signal into a first voltage signal and a second voltage signal; the diagnosis module is connected with the conversion module, and the diagnosis module is used for rectifying the first voltage signal to generate a third voltage signal; the conversion module and the diagnosis module are both connected with the processing module, and the processing module is used for identifying the current pulse signal according to the second voltage signal and judging the running state of the current pulse modulation identification circuit according to the third voltage signal. The current pulse modulation identification circuit provided by the embodiment of the present application can quickly process and identify the current pulse signal.

Description

TECHNICAL FIELD

[0001] The embodiment of the present application relates to the field of pulse signal modulation technology, in particular to a current pulse modulation identification circuit. BACKGROUND

[0002] There is a Hall type sensor in an automobile sensor, which is used to collect the rotating speed information of a transmission shaft, a motor output shaft and an engine output shaft. The sensor outputs a current type pulse width modulation signal (PWM signal), and the current type PWM signal cannot be directly collected by a microcontroller unit (MCU) master control chip. Therefore, under the premise of guaranteeing automobile application and test conditions, how to convert the current type PWM signal into a voltage type PWM signal that can be recognized by the MCU in the controller is a main problem to be solved. SUMMARY

[0003] The embodiment of the present application provides a current pulse modulation identification circuit to realize fast processing and identification of a current pulse signal.

[0004] The embodiment of the present application provides a current pulse modulation identification circuit, which comprises a protection module, a conversion module, a diagnosis module and a processing module.

[0005] The protection module is used for receiving a current pulse signal and protecting the conversion module, the diagnosis module and the processing module; the protection module is connected with the conversion module, and the conversion module is used for converting the current pulse signal into a first voltage signal and a second voltage signal; the diagnosis module is connected with the conversion module, and the diagnosis module is used for rectifying the first voltage signal to generate a third voltage signal; the conversion module and the diagnosis module are both connected with the processing module, and the processing module is used for identifying the current pulse signal according to the second voltage signal and judging the running state of the current pulse modulation identification circuit according to the third voltage signal.

[0006] Optionally, the protection module comprises an anti-static unit and an anti-short circuit unit.

[0007] The anti-static unit and the anti-short circuit unit are connected, and the anti-short circuit unit is connected with the conversion module; the anti-static unit is used for filtering static electricity input by an input port, and the anti-short circuit unit is used for protecting the conversion module, the diagnosis module and the processing module when short circuit occurs in the input port.

[0008] Optionally, the anti-static unit comprises a first capacitor.

[0009] The anti-short circuit unit comprises a first resistor, a second resistor and a triode.

[0010] The first terminal of the first capacitor, the input port, and the first terminal of the first resistor are connected together. The second terminal of the first capacitor is grounded. The second terminal of the first resistor is connected to the first terminal of the transistor. The control terminal of the transistor is connected to the first terminal of the second resistor. The second terminal of the transistor is connected to the conversion module. The second terminal of the second resistor is connected to the first fixed potential.

[0011] Optionally, the conversion module includes a current-to-voltage conversion unit and a level conversion unit;

[0012] The protection module is connected to the current-to-voltage conversion unit, and the current-to-voltage conversion unit is connected to the level conversion unit.

[0013] The current-to-voltage conversion unit is used to convert the current pulse signal into the first voltage signal, and the level conversion unit is used to convert the first voltage signal into the second voltage signal.

[0014] Optionally, the current-to-voltage conversion unit includes a third resistor;

[0015] The first terminal of the third resistor, the protection module, and the level conversion unit are connected.

[0016] Optionally, the level conversion unit includes a voltage divider subunit, a switching subunit, a current limiting subunit, and a first filtering subunit;

[0017] The first end of the voltage divider subunit is connected to the current-to-voltage conversion unit, the second end of the voltage divider subunit is connected to the control end of the switch subunit, the first end of the switch subunit, the first end of the current limiting subunit, the first end of the first filter subunit and the processing module are connected, the second end of the current limiting subunit is connected to the second fixed potential, and the second end of the switch subunit and the second end of the first filter subunit are both grounded.

[0018] Optionally, the voltage divider subunit includes a fourth resistor and a fifth resistor; the switching subunit includes a MOSFET; the current limiting subunit includes a sixth resistor; and the first filtering subunit includes a second capacitor.

[0019] The first end of the fourth resistor is connected to the current-to-voltage conversion unit. The second end of the fourth resistor, the first end of the fifth resistor, and the control terminal of the MOSFET are connected. The first electrode of the MOSFET, the first end of the sixth resistor, the first end of the second capacitor, and the processing module are connected. The second electrode of the MOSFET and the second end of the second capacitor are both grounded. The second end of the sixth resistor is connected to the second fixed potential.

[0020] Optionally, the diagnostic module includes a first filtering unit and a second filtering unit;

[0021] The first end of the first filtering unit is connected to the conversion module, the second end of the first filtering unit is connected to the first end of the second filtering unit, and the second end of the second filtering unit is connected to the processing module; the first filtering unit is used to rectify the first voltage signal to generate a rectified signal, and the second filtering unit is used to rectify the rectified signal to generate a third voltage signal.

[0022] Optionally, the first filter unit includes a seventh resistor and a third capacitor, and the second filter unit includes an eighth resistor and a fourth capacitor;

[0023] The first end of the seventh resistor is connected to the conversion module. The second end of the seventh resistor, the first end of the third capacitor, and the first end of the eighth resistor are connected. The second end of the eighth resistor, the first end of the fourth capacitor, and the processing module are connected. The second ends of the third capacitor and the second ends of the fourth capacitor are both grounded.

[0024] Optionally, the processing module includes a microcontroller.

[0025] The current pulse modulation identification circuit provided in this embodiment of the invention includes a protection module that protects the conversion module, diagnostic module, and processing module, thereby preventing damage to these modules from large input current signals and ensuring that devices using the current pulse modulation identification circuit are not damaged. The conversion module performs current-to-voltage conversion signal processing on the current pulse signal to generate a first voltage signal, and then performs amplitude processing on the first voltage signal to generate a second voltage signal, thus converting the current pulse signal that the processing module cannot recognize into a second voltage signal that the processing module can recognize. The diagnostic module samples and rectifies the first voltage signal to generate a third voltage signal that reflects the operating status of the current pulse modulation identification circuit. Therefore, the processing module can accurately identify the information contained in the current pulse signal based on the second voltage signal and determine the current operating status of the current pulse width modulation identification circuit based on the third voltage signal. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of a current pulse modulation recognition circuit provided in an embodiment of the present invention;

[0028] Figure 2 This is a schematic diagram of another current pulse modulation recognition circuit provided in an embodiment of the present invention;

[0029] Figure 3 This is a schematic diagram of another current pulse modulation recognition circuit provided in an embodiment of the present invention;

[0030] Figure 4 This is a schematic diagram of another current pulse modulation recognition circuit provided in an embodiment of the present invention;

[0031] Figure 5 This is a schematic diagram of another current pulse modulation recognition circuit provided in an embodiment of the present invention;

[0032] Figure 6 This is a schematic diagram of another current pulse modulation recognition circuit provided in an embodiment of the present invention. Detailed Implementation

[0033] 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 of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0034] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention 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 so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a 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.

[0035] Figure 1 This is a schematic diagram of a current pulse modulation identification circuit provided in an embodiment of the present invention, as shown below. Figure 1As shown, the current pulse modulation identification circuit includes a protection module 110, a conversion module 120, a diagnostic module 130, and a processing module 140. The protection module 110 is used to receive current pulse signals and protect the conversion module 120, the diagnostic module 130, and the processing module 140. The protection module 110 is connected to the conversion module 120, which is used to convert the current pulse signal into a first voltage signal and a second voltage signal. The diagnostic module 130 is connected to the conversion module 120 and is used to rectify the first voltage signal to generate a third voltage signal. Both the conversion module 120 and the diagnostic module 130 are connected to the processing module 140, which is used to identify the current pulse signal based on the second voltage signal and determine the operating status of the current pulse modulation identification circuit based on the third voltage signal.

[0036] The protection module 110 serves as a protection device for the current pulse modulation identification circuit. The input port of the current pulse modulation identification circuit is connected to the protection module 110. All signals input to the input port must be filtered by the protection module 110 before being input to the subsequent circuitry, thus protecting the conversion module 120, diagnostic module 130, and processing module 140. The conversion module 120 is the execution device for the current pulse modulation identification circuit. It processes the input signals, converting them into signals that the processing module 140 can recognize. For example, it converts a current pulse signal that the processing module 140 cannot recognize into a second voltage signal that the processing module 140 can recognize. The diagnostic module 130 is the monitoring device for the current pulse modulation identification circuit. It can monitor the operating status of the entire current pulse modulation identification circuit in real time and generate a signal (a third voltage signal) that provides real-time feedback on the operating status of the current pulse modulation identification circuit. The processing module 140 is an information reading device for the current pulse modulation recognition circuit. It can identify the signal generated by the conversion module 120 and read and judge the signal generated by the diagnostic module 130. For example, the processing module 140 identifies the current pulse signal based on the second voltage signal and judges the operating status of the current pulse width modulation recognition circuit based on the third voltage signal.

[0037] Based on the connection relationships of the various modules of the current pulse modulation identification circuit, the working process of the current pulse modulation identification circuit is as follows: When a current pulse signal is input to the input port, if the current pulse signal is mixed with static electricity, the protection module 110 will filter out the mixed static electricity and output the cleaned current pulse signal to the conversion module 120. After receiving the current pulse signal, the conversion module 120 first performs current-to-voltage conversion processing on the current pulse signal to generate a first voltage signal, and then performs amplitude processing on the first voltage signal to generate a second voltage signal. At the same time, the conversion module 120 transmits the first voltage signal to the diagnostic module 130 and the second voltage signal to the processing module 140. After receiving the first voltage signal, the diagnostic module 130 samples and rectifies the first voltage signal to generate a third voltage signal that can reflect the operating status of the current pulse modulation identification circuit, and sends the third voltage signal to the processing module 140. When the processing module 140 receives the second voltage signal, it will identify the second voltage signal to generate control commands based on the second voltage signal. When the protection module 110 receives the third voltage signal, it will judge the third voltage signal to confirm the current operating status of the current pulse width modulation identification circuit. In addition, when the input port of the current pulse modulation identification circuit is short-circuited with the power supply, the protection module 110 can quickly disconnect from the subsequent circuits to prevent the input power signal from entering the conversion module 120, diagnostic module 130 and processing module 140 through the protection module 110, thereby avoiding damage to the conversion module 120, diagnostic module 130 and processing module 140 by the input large current signal.

[0038] The current pulse modulation identification circuit provided in this embodiment of the invention includes a protection module 110 that protects the conversion module 120, diagnostic module 130, and processing module 140, thereby preventing damage to these modules from large input current signals and ensuring that devices using the current pulse modulation identification circuit are not damaged. The conversion module performs current-to-voltage conversion signal processing on the current pulse signal to generate a first voltage signal, and then performs amplitude processing on the first voltage signal to generate a second voltage signal, thus converting the current pulse signal that the processing module 140 cannot recognize into a second voltage signal that the processing module 140 can recognize. The diagnostic module 130 samples and rectifies the first voltage signal to generate a third voltage signal that reflects the operating state of the current pulse modulation identification circuit. Therefore, the processing module 140 can accurately identify the information contained in the current pulse signal based on the second voltage signal and determine the current operating state of the current pulse width modulation identification circuit based on the third voltage signal.

[0039] Optionally, based on the above embodiments, Figure 2 This is a schematic diagram of another current pulse modulation recognition circuit provided in an embodiment of the present invention, as shown below.Figure 2 As shown, the protection module 110 includes an anti-static unit 111 and a short-circuit protection unit 112; the anti-static unit 111 and the short-circuit protection unit 112 are connected, and the short-circuit protection unit 112 is connected to the conversion module 120; the anti-static unit 111 is used to filter out static electricity input at the input port, and the short-circuit protection unit 112 is used to protect the conversion module 120, the diagnostic module 130, and the processing module 140 when a short circuit occurs at the input port.

[0040] Specifically, the input port of the current pulse modulation identification circuit is connected to the first terminal of the anti-static unit 111, the second terminal of the anti-static unit 111 is connected to the first terminal of the short-circuit protection unit 112, and the second terminal of the short-circuit protection unit 112 is connected to the conversion module 120. All signals input to the input port must be filtered sequentially by the anti-static unit 111 and the short-circuit protection unit 112 before being input to the subsequent circuitry, thereby protecting the conversion module 120, the diagnostic module 130, and the processing module 140. When a current pulse signal doped with static electricity is input to the input port, the anti-static unit 111 filters out the static electricity doping from the current pulse signal and outputs the purified current pulse signal to the short-circuit protection unit 112. The short-circuit protection unit 112 can determine the connection status of the input port based on the input signal, and quickly disconnects the connection with the subsequent circuit when a short circuit occurs at the input port. This prevents the input signal from being input to the conversion module 120, diagnostic module 130, and processing module 140 through the protection module 110, thereby avoiding damage to the conversion module 120, diagnostic module 130, and processing module 140 by the input high-current signal. If the signal input to the short-circuit protection unit 112 is a current pulse signal, the short-circuit protection unit 112 will conduct normally. If the input port is short-circuited to the power supply, the signal input to the short-circuit protection unit 112 will be a power signal. In this case, the short-circuit protection unit 112 will quickly disconnect the connection with the conversion module 120 to ensure the safety of the subsequent circuit.

[0041] Optionally, based on the above embodiments, Figure 3 This is a schematic diagram of another current pulse modulation recognition circuit provided in an embodiment of the present invention, as shown below. Figure 3 As shown, the conversion module 120 includes a current-to-voltage conversion unit 121 and a level conversion unit 122; the protection module 110 is connected to the current-to-voltage conversion unit 121, and the current-to-voltage conversion unit 121 and the level conversion unit 122 are connected; the current-to-voltage conversion unit 121 is used to convert the current pulse signal into a first voltage signal, and the level conversion unit 122 is used to convert the first voltage signal into a second voltage signal.

[0042] Specifically, the short-circuit protection unit 112 is connected to the current-to-voltage conversion unit 121. The short-circuit protection unit 112 outputs a current pulse signal to the current-to-voltage conversion unit 121, which performs current-to-voltage conversion processing on the current pulse signal to generate a first voltage signal. The current-to-voltage conversion unit 121 is connected to the level conversion unit 122. The current-to-voltage conversion unit 121 transmits the generated first voltage signal to the level conversion unit 122, which performs amplitude processing on the first voltage signal to generate a second voltage signal. Thus, the current-to-voltage conversion unit 121 and the level conversion unit 122 convert the current pulse signal, which the processing module 140 cannot recognize, into a second voltage signal that the processing module 140 can recognize.

[0043] Optionally, based on the above embodiments, Figure 4 This is a schematic diagram of another current pulse modulation recognition circuit provided in an embodiment of the present invention, as shown below. Figure 4 As shown, the level conversion unit 122 includes a voltage divider subunit 1221, a switch subunit 1222, a current limiting subunit 1223, and a first filter subunit 1224. The first end of the voltage divider subunit 1221 is connected to the current-to-voltage conversion unit 121, and the second end of the voltage divider subunit 1221 is connected to the control terminal of the switch subunit 1222. The first end of the switch subunit 1222, the first end of the current limiting subunit 1223, the first end of the first filter subunit 1224, and the processing module 140 are connected. The second end of the current limiting subunit 1223 is connected to the second fixed potential V2. The second ends of the switch subunit 1222 and the second ends of the first filter subunit 1224 are both grounded.

[0044] Specifically, the first terminal of the voltage divider unit is connected to the current-to-voltage conversion unit 121, and the second terminal of the voltage divider subunit 1221 is connected to the control terminal of the switch subunit 1222. The voltage divider unit can adjust the second voltage signal so that the voltage signal after voltage division adjustment can control the on / off state of the switch subunit 1222. That is, the switch subunit 1222 can turn on or off its first and second terminals according to the voltage signal after voltage division adjustment input from the control terminal. The second terminal of the current limiting subunit 1223 is connected to the second fixed potential V2. The first terminals of the switch subunit 1222, the current limiting subunit 1223, the first terminal of the first filter subunit 1224, and the processing module 140 are connected. Thus, when the first and second terminals of the switch subunit 1222 are on, the current limiting subunit 1223 can control the current flowing into the switch subunit 1222 and the processing module 140 to prevent the switch subunit 1222 and the processing module 140 from being burned out due to excessive input current. Since the signal will be affected by various interferences and fluctuate during transmission, the first filtering subunit 1224 can filter out the interference waves mixed in the signal of the input processing module 140 to improve the accuracy of the signal received by the processing module 140.

[0045] Optionally, based on the above embodiments, Figure 5 This is a schematic diagram of another current pulse modulation recognition circuit provided in an embodiment of the present invention, as shown below. Figure 5 As shown, the diagnostic module 130 includes a first filtering unit 131 and a second filtering unit 132; the first end of the first filtering unit 131 is connected to the conversion module 120, the second end of the first filtering unit 131 is connected to the first end of the second filtering unit 132, and the second end of the second filtering unit 132 is connected to the processing module 140; the first filtering unit 131 is used to rectify the first voltage signal to generate a rectified signal, and the second filtering unit 132 is used to rectify the rectified signal to generate a third voltage signal.

[0046] Specifically, the first terminal of the first filtering unit 131 is connected to the current-to-voltage conversion unit 121, which transmits the first voltage signal to the first filtering unit 131. The first filtering unit 131 rectifies the input first voltage signal to generate a rectified signal. The second terminal of the first filtering unit 131 is connected to the first terminal of the second filtering unit 132, which rectifies the input rectified signal to generate a third voltage signal that reflects the operating status of the current pulse modulation identification circuit. Thus, the first filtering unit 131 and the second filtering unit 132 perform two-stage filtering on the input first voltage signal, transforming the pulsed first voltage signal into a near-DC third voltage signal.

[0047] It should be noted that the number of filter units set in the diagnostic module 130 can be determined as needed. The purpose is to convert the pulsed first voltage signal into a third voltage signal that is approximately DC, so that the subsequent processing module 140 can determine the current pulse width modulation identification circuit's operating status based on the third voltage signal.

[0048] Optionally, based on the above embodiments, Figure 6 This is a schematic diagram of another current pulse modulation recognition circuit provided in an embodiment of the present invention, as shown below. Figure 6 As shown, the anti-static unit 111 includes a first capacitor C1; the short-circuit protection unit 112 includes a first resistor R1, a second resistor R2, and a transistor Q1; the first terminal of the first capacitor C1, the input port SG, and the first terminal of the first resistor R1 are connected, the second terminal of the first capacitor C1 is grounded, the second terminal of the first resistor R1 is connected to the first terminal of the transistor Q1, the control terminal of the transistor Q1 is connected to the first terminal of the second resistor R2, the second terminal of the transistor Q1 is connected to the conversion module 120, and the second terminal of the second resistor R2 is connected to the first fixed potential V1.

[0049] The first capacitor C1 serves a filtering function, filtering all signals input to the input port SG to remove static electricity or current pulse signals from the input port SG, thus preventing damage to the current pulse modulation circuit from electrostatic input. The first capacitor C1 is composed of an electrostatic discharge (ESD) ceramic capacitor. The actual selection of the first capacitor C1 can be based on the requirements of the actual environment in which the current pulse width modulation identification circuit operates. Alternatively, the first capacitor C1 can be replaced by a transient voltage suppressor (TVS) with electrostatic discharge protection.

[0050] The short-circuit protection unit 112 includes a first resistor R1, a second resistor R2, and a transistor Q1. The first terminal of transistor Q1 can be the collector, the control terminal can be the base, and the second terminal can be the emitter. Specifically, the second terminal of the first resistor R1 is connected to the collector of transistor Q1, the base of transistor Q1 is connected to the first terminal of the second resistor R2, and the emitter of transistor Q1 is connected to the conversion module 120. Resistor R1 samples the voltage formed by the input current pulse signal to determine the magnitude of the input voltage at the collector of transistor Q1. The second resistor R2 limits current to prevent the current input to the base of transistor Q1 from burning it out. Based on the operating characteristics of transistor Q1, when the emitter potential is not higher than the clamping voltage of the first fixed potential V1, a short circuit at the input port SG to the power supply can be avoided, preventing damage to the current pulse modulation identification circuit. When the emitter potential of the transistor is higher than the VCC clamping voltage of the first fixed potential V1, the collector and emitter of the transistor Q1 can be kept connected, allowing the current pulse signal to flow into the conversion module 120.

[0051] Optionally, based on the above embodiments, continue to refer to... Figure 6 The current-to-voltage conversion unit 121 includes a third resistor R3; the first end of the third resistor R3 is connected to the protection module 110 and the level conversion unit 122.

[0052] The third resistor R3 can convert the current pulse signal into a first voltage signal. However, the amplitude of the high and low levels of the first voltage signal may not be within the range that the processing module 140 can recognize. Therefore, the first voltage signal needs to be further processed.

[0053] In addition, when the input port SG is short-circuited to the power supply, the voltage division through the third resistor R3, transistor Q1, and second resistor R2 will cause the third resistor R3, transistor Q1, and second resistor R2 to operate in a low-power state. That is, the current flowing through the third resistor R3, transistor Q1, and second resistor R2 is extremely small. The third resistor R3, transistor Q1, and second resistor R2 can be selected with small resistance, thereby effectively saving the design area of ​​the current pulse modulation recognition circuit under the condition of the input port SG being short-circuited to the power supply.

[0054] Optionally, based on the above embodiments, continue to refer to... Figure 6The voltage divider subunit 1221 includes a fourth resistor R4 and a fifth resistor R5; the switching subunit 1222 includes a MOSFET D1; the current limiting subunit 1223 includes a sixth resistor R6; the first filter subunit 1224 includes a second capacitor C2; the first end of the fourth resistor R4 is connected to the current-to-voltage conversion unit 121; the second end of the fourth resistor R4, the first end of the fifth resistor R5, and the control terminal of the MOSFET D1 are connected; the first pole of the MOSFET D1, the first end of the sixth resistor R6, the first end of the second capacitor C2, and the processing module 140 are connected; the second pole of the MOSFET D1 and the second end of the second capacitor C2 are both grounded; and the second end of the sixth resistor R6 is connected to the second fixed potential V2.

[0055] Specifically, the fourth resistor R4 and the fifth resistor R5 are used to divide the first voltage signal converted by the third resistor R3. This allows the control terminal of MOSFET D1 to disconnect the connection between its first and second terminals when the first voltage signal converted from the input current pulse signal is low, and to connect the first and second terminals of MOSFET D1 when the first voltage signal converted from the input current pulse signal is high. The sixth resistor R6 has a current-limiting function, reducing the current input to the processing module 140 when the first and second terminals of MOSFET D1 are conducting, ensuring that the processing module 140 is not burned out due to excessive input current. Additionally, the capacitor has a filtering function; the second capacitor C2 filters out noise in the voltage signal input to the processing module 140 when the first and second terminals of MOSFET D1 are conducting, preventing voltage fluctuations from affecting the accuracy of the input voltage signal to the processing module 140.

[0056] Optionally, based on the above embodiments, refer to... Figure 6 The first filter unit 131 includes a seventh resistor R7 and a third capacitor C3, and the second filter unit 132 includes an eighth resistor R8 and a fourth capacitor C4. The first end of the seventh resistor R7 is connected to the conversion module 120, the second end of the seventh resistor R7, the first end of the third capacitor C3 and the first end of the eighth resistor R8 are connected, the second end of the eighth resistor R8, the first end of the fourth capacitor C4 and the processing module 140 are connected, and the second ends of the third capacitor C3 and the second ends of the fourth capacitor C4 are both grounded.

[0057] The seventh resistor R7 and the third capacitor C3 form an RC filter, and the eighth resistor R8 and the fourth capacitor C4 form another RC filter. When the first voltage signal passes through the two RC filters, an approximately DC voltage signal can be obtained and transmitted to the processing module 140.

[0058] Optionally, based on the above embodiments, refer to... Figure 6The processing module 140 includes a microcontroller.

[0059] A microcontroller is an integrated circuit chip that uses very large-scale integrated circuit (VLSI) technology to integrate a central processing unit (CPU) with data processing capabilities, random access memory (RAM), read-only memory (ROM), various I / O ports and interrupt systems, timers / counters, and other functions (and possibly display driver circuits, pulse width modulation circuits, analog multiplexers, A / D converters, etc.) onto a single silicon chip, forming a small but complete microcomputer system. It can quickly identify and process input signals. Therefore, a microcontroller can quickly identify a current pulse signal based on a second voltage signal and quickly determine the operating status of the current pulse width modulation identification circuit based on a third voltage signal.

[0060] For example, when the resistance of the first resistor R1 is 221 ohms, the resistance of the third resistor R3 is 274 ohms, and the resistance of the second resistor R2 is 4.02 Kohms, the high level of the first voltage signal generated across the third resistor R3 is 3.35V, and the low level of the first voltage signal is 2.34V. The level conversion unit 122 converts the first voltage signal into a second voltage signal with a high level of 5V and a low level of 0V, thereby enabling the processing module 140 to recognize the converted second voltage.

[0061] In addition, when the third voltage signal output by the diagnostic module 130 is 2.5V to 3V, the processing module 140 determines that the current pulse width modulation identification circuit is in normal operation. When the third voltage signal output by the diagnostic module 130 is 4V to 5V, the processing module 140 determines that the current pulse width modulation identification circuit is in the first fault state, that is, the input port SG of the current pulse width modulation identification circuit is short-circuited to the power supply. When the third voltage signal output by the diagnostic module 130 is 0.2V to 0.5V, the processing module 140 determines that the current pulse width modulation identification circuit is in the second fault state, that is, the input port SG of the current pulse width modulation identification circuit is short-circuited to ground.

[0062] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0063] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A current pulse modulation identification circuit, characterized in that, It includes a protection module, a conversion module, a diagnostic module, and a processing module; The protection module is used to receive current pulse signals and protect the conversion module, the diagnostic module, and the processing module. The protection module is connected to the conversion module, which converts the current pulse signal into a first voltage signal and a second voltage signal. The diagnostic module is connected to the conversion module and rectifies the first voltage signal to generate a third voltage signal. Both the conversion module and the diagnostic module are connected to the processing module, which identifies the current pulse signal based on the second voltage signal and determines the operating status of the current pulse modulation identification circuit based on the third voltage signal. The step of determining the operating state of the current pulse width modulation identification circuit based on the third voltage signal includes: if the third voltage signal is within a first voltage range, the processing module determines that the operating state of the current pulse width modulation identification circuit is a normal operating state; if the third voltage signal is within a second voltage range, the processing module determines that the operating state of the current pulse width modulation identification circuit is a first fault state, that is, the input port of the current pulse width modulation identification circuit is short-circuited to the power supply; if the third voltage signal is within a third voltage range, the processing module determines that the operating state of the current pulse width modulation identification circuit is a second fault state, that is, the input port of the current pulse width modulation identification circuit is short-circuited to ground. The protection module includes an anti-static unit and a short-circuit protection unit. The anti-static unit and the short-circuit protection unit are connected, and the short-circuit protection unit is connected to the conversion module; the anti-static unit is used to filter out static electricity input from the input port, and the short-circuit protection unit is used to protect the conversion module, the diagnostic module, and the processing module when a short circuit occurs at the input port; The anti-static unit includes a first capacitor; The short-circuit protection unit includes a first resistor, a second resistor, and a transistor; The first terminal of the first capacitor, the input port, and the first terminal of the first resistor are connected together. The second terminal of the first capacitor is grounded. The second terminal of the first resistor is connected to the first terminal of the transistor. The control terminal of the transistor is connected to the first terminal of the second resistor. The second terminal of the transistor is connected to the conversion module. The second terminal of the second resistor is connected to the first fixed potential. If a current pulse signal doped with static electricity is input to the input port, the anti-static unit will filter out the static electricity doped in the current pulse signal and output the de-doped current pulse signal to the short-circuit protection unit. The short-circuit protection unit determines the connection status of the input port based on the input signal, and quickly disconnects the connection with the subsequent circuit when a short circuit occurs at the input port. If the signal input to the short-circuit protection unit is a current pulse signal, the short-circuit protection unit will conduct normally. If the input port is short-circuited to the power supply, the signal input to the short-circuit protection unit will be a power signal. In this case, the short-circuit protection unit will quickly disconnect from the conversion module to ensure the safety of the subsequent circuit.

2. The current pulse modulation identification circuit according to claim 1, characterized in that, The conversion module includes a current-to-voltage conversion unit and a level conversion unit; The protection module is connected to the current-to-voltage conversion unit, and the current-to-voltage conversion unit is connected to the level conversion unit. The current-to-voltage conversion unit is used to convert the current pulse signal into the first voltage signal, and the level conversion unit is used to convert the first voltage signal into the second voltage signal.

3. The current pulse modulation identification circuit according to claim 2, characterized in that, The current-to-voltage conversion unit includes a third resistor; The first terminal of the third resistor, the protection module, and the level conversion unit are connected.

4. The current pulse modulation identification circuit according to claim 2, characterized in that, The level conversion unit includes a voltage divider subunit, a switching subunit, a current limiting subunit, and a first filtering subunit; The first end of the voltage divider subunit is connected to the current-to-voltage conversion unit, the second end of the voltage divider subunit is connected to the control end of the switch subunit, the first end of the switch subunit, the first end of the current limiting subunit, the first end of the first filter subunit and the processing module are connected, the second end of the current limiting subunit is connected to the second fixed potential, and the second end of the switch subunit and the second end of the first filter subunit are both grounded.

5. The current pulse modulation identification circuit according to claim 4, characterized in that, The voltage divider subunit includes a fourth resistor and a fifth resistor; the switching subunit includes a MOSFET; the current limiting subunit includes a sixth resistor; the first filter subunit includes a second capacitor; The first end of the fourth resistor is connected to the current-to-voltage conversion unit. The second end of the fourth resistor, the first end of the fifth resistor, and the control terminal of the MOSFET are connected. The first electrode of the MOSFET, the first end of the sixth resistor, the first end of the second capacitor, and the processing module are connected. The second electrode of the MOSFET and the second end of the second capacitor are both grounded. The second end of the sixth resistor is connected to the second fixed potential.

6. The current pulse modulation identification circuit according to claim 1, characterized in that, The diagnostic module includes a first filtering unit and a second filtering unit; The first end of the first filtering unit is connected to the conversion module, the second end of the first filtering unit is connected to the first end of the second filtering unit, and the second end of the second filtering unit is connected to the processing module; the first filtering unit is used to rectify the first voltage signal to generate a rectified signal, and the second filtering unit is used to rectify the rectified signal to generate a third voltage signal.

7. The current pulse modulation identification circuit according to claim 6, characterized in that, The first filter unit includes a seventh resistor and a third capacitor, and the second filter unit includes an eighth resistor and a fourth capacitor; The first end of the seventh resistor is connected to the conversion module. The second end of the seventh resistor, the first end of the third capacitor, and the first end of the eighth resistor are connected. The second end of the eighth resistor, the first end of the fourth capacitor, and the processing module are connected. The second ends of the third capacitor and the second ends of the fourth capacitor are both grounded.

8. The current pulse modulation identification circuit according to claim 1, characterized in that, The processing module includes a microcontroller.

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