Duty ratio correction device and synchronous acquisition system
By using a duty cycle correction device and a dynamic feedback mechanism, the problem of accuracy and reliability of the acquired data caused by clock signal duty cycle distortion was solved, and the stability and efficient operation of the multi-device synchronous acquisition system were achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SHENZHEN CITY SIGLENT TECH
- Filing Date
- 2025-03-28
- Publication Date
- 2026-04-14
AI Technical Summary
In a multi-device synchronous acquisition system, distortion of the clock signal duty cycle leads to a decrease in the accuracy and reliability of the sampling data, affects the time alignment of the data and the communication synchronization between devices, and may damage the hardware circuit and increase maintenance costs.
A duty cycle correction device is adopted, including an input port, a signal processing module, a duty cycle correction module, and an output port. Through filtering, DC blocking, and duty cycle correction processing, combined with a dynamic feedback mechanism, the stability and consistency of the clock signal are ensured.
It improved the accuracy and reliability of signal acquisition, optimized system performance, ensured data accuracy and equipment stability, and reduced maintenance costs.
Smart Images
Figure CN224124116U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of electronic circuit technology, specifically to a duty cycle correction device and a synchronous acquisition system. Background Technology
[0002] Multi-device synchronous data acquisition systems are highly integrated systems, representing an integrated technology platform capable of simultaneously acquiring, accurately synchronizing, and efficiently processing data from multiple devices or sensors in real time. They are widely used in numerous fields such as industrial automation, energy management, transportation, healthcare, aerospace, smart homes, and security. By achieving precise synchronization and comprehensive analysis of multi-source data, this system not only significantly improves production efficiency, equipment reliability, and energy utilization efficiency but also promotes the realization of advanced functions such as remote monitoring, intelligent decision-making, and predictive maintenance.
[0003] Unified clock signals are the cornerstone of ensuring accurate data alignment and collaborative operation among multiple devices, and the duty cycle of the clock signal is also a factor that needs to be considered. However, in practice, in a cascaded multi-device synchronous acquisition system, the clock signal of each acquisition device comes from the acquisition device of the previous level. In the clock signal transmission link, the duty cycle of the clock signal can be distorted due to buffer lag and cable differences.
[0004] Clock signal duty cycle distortion has several adverse effects. First, it causes an imbalance in the duration of high and low levels in the clock signal, shifting or compressing the effective sampling window within the sampling period, leading to biased and incomplete sampled data. This bias is particularly pronounced in synchronous acquisition scenarios requiring precise time alignment, potentially causing data from different devices to not correspond accurately in the time dimension, affecting data comparability and analytical accuracy. Second, duty cycle distortion can also cause communication synchronization problems between devices, as clock signal instability can lead to data transmission timing errors, increasing the risk of data loss or errors. Furthermore, long-term duty cycle distortion can damage the hardware circuitry of devices, shortening their lifespan and increasing system maintenance costs.
[0005] Therefore, in a multi-device synchronous acquisition system, maintaining the stability and consistency of the clock signal duty cycle is crucial. Utility Model Content
[0006] This invention provides a duty cycle correction device and a synchronous acquisition system with the duty cycle correction device, which can solve the technical problem of decreased accuracy and reliability of signal acquisition data caused by distortion of the input signal duty cycle in existing signal acquisition equipment.
[0007] In a first aspect, embodiments of this application provide a duty cycle correction device, characterized in that it includes:
[0008] Input port, used to receive input signals;
[0009] A signal processing module, connected to the input port, is used to filter and block DC from the received input signal to obtain a processed first signal;
[0010] A duty cycle correction module, connected to the signal processing module, is used to acquire the first signal, compare the acquired first signal with a preset threshold, and perform duty cycle correction on the first signal according to the comparison result and the target duty cycle to obtain an output signal corrected relative to the input signal.
[0011] The output port is connected to the duty cycle correction module and is used to output the corrected output signal to the connected terminal.
[0012] In some embodiments, the duty cycle correction device further includes a dynamic feedback module connected between the output port and the duty cycle correction module;
[0013] The dynamic feedback module is used to extract the DC component of the corrected output signal, compare the DC component with a reference signal, and generate dynamic feedback information based on the comparison result and output it to the duty cycle correction module.
[0014] The duty cycle of the reference signal is the same as that of the target signal;
[0015] The dynamic feedback information includes at least one of the threshold adjustment information and the bias voltage adjustment information of the first signal;
[0016] The duty cycle correction module is also used to adjust the threshold value and / or adjust the bias voltage of the first signal according to the dynamic feedback information, and to perform duty cycle correction on the first signal again to obtain the dynamically corrected output signal and output it.
[0017] In some embodiments, the duty cycle correction module includes at least a shaping circuit; the first input terminal of the shaping circuit is connected to the output terminal of the signal processing module, the second input terminal of the shaping circuit is connected to the output terminal of the dynamic feedback module, and the output terminal of the shaping circuit is connected to the output port.
[0018] Specifically, when the first signal is higher than the threshold, the shaping circuit outputs a first level; when the first signal is lower than the threshold, the shaping circuit outputs a second level.
[0019] Alternatively, when the first signal is below the threshold, the shaping circuit outputs a first level; when the first signal is above the threshold, the shaping circuit outputs a second level.
[0020] In some embodiments, the shaping circuit includes a threshold configuration unit; the threshold configuration unit is used to configure a preset threshold or to configure a threshold based on the dynamic feedback information.
[0021] In some embodiments, the shaping circuitry includes any one of a Schmitt trigger, a comparator, a digital buffer, and an inverter.
[0022] In some embodiments, the duty cycle correction module includes a bias superposition circuit; the first input terminal of the bias superposition circuit is connected to the output terminal of the signal processing module, and the second input terminal of the bias superposition circuit is connected to the output terminal of the dynamic feedback module; the input terminal of the shaping circuit is connected to the output terminal of the bias superposition circuit, and the output terminal of the shaping circuit is connected to the output port.
[0023] The bias superposition circuit is used to adjust the bias voltage of the first signal according to the bias adjustment information characterizing the first signal in the dynamic feedback information, and output the adjusted first signal.
[0024] In some embodiments, the bias superposition circuit includes at least a damping resistor and a filter capacitor connected in series;
[0025] The first end of the damping resistor is connected to the first input terminal of the bias superposition circuit, and the second end of the damping resistor is connected to the second input terminal of the bias superposition circuit; the second end of the filter capacitor is connected to the preset voltage terminal.
[0026] In some embodiments, the dynamic feedback module includes at least a second low-pass filter and an operational amplifier; the second low-pass filter is used to extract the DC component of the corrected output signal; the operational amplifier is used to output dynamic feedback information based on the comparison result of the DC component and the reference signal.
[0027] The input terminal of the second low-pass filter is connected to the input terminal of the dynamic feedback module; the non-inverting input terminal of the operational amplifier is used to acquire the reference signal, the inverting input terminal of the operational amplifier is connected to the output terminal of the second low-pass filter, and the output terminal of the operational amplifier is connected to the output terminal of the dynamic feedback module.
[0028] Wherein, when the DC component is greater than the reference signal, the operational amplifier outputs a first bias adjustment signal representing a reduction in the bias voltage of the first signal and / or a first threshold adjustment signal representing a reduction in the threshold value; when the DC component is less than the reference signal, the operational amplifier outputs a second bias signal representing an increase in the bias voltage of the first signal and / or a second threshold adjustment signal representing an increase in the threshold value.
[0029] Alternatively, when the DC component is greater than the reference signal, the operational amplifier outputs a first bias signal representing an increase in the bias voltage of the first signal and / or a first threshold adjustment signal representing an increase in the threshold value; when the DC component is less than the reference signal, the operational amplifier outputs a second bias signal representing a decrease in the bias voltage of the first signal and / or a second threshold adjustment signal representing a decrease in the threshold value.
[0030] In some embodiments, the signal processing module includes at least a first low-pass filter and a DC blocker connected in sequence; the first low-pass filter is used to filter out high-frequency components in the input signal to smooth the edges of the input signal; the DC blocker is used to eliminate DC bias in the input signal to make the input signal symmetrical about the zero axis.
[0031] Secondly, embodiments of this application provide a synchronous acquisition system, including multiple cascaded signal acquisition devices and a duty cycle correction device as described in any of the above embodiments, disposed in each signal acquisition device;
[0032] Among them, the clock signal input terminal of the first-level signal acquisition device is used to acquire the externally input clock signal, and the clock signal of the clock signal input terminal of each other signal acquisition device comes from the clock signal of the previous level signal acquisition device.
[0033] The duty cycle correction device in each level of signal acquisition equipment is used to correct the duty cycle of the clock signal received by the signal acquisition equipment at this level according to the target duty cycle, so as to keep the clock signal received by each level of signal acquisition equipment synchronized.
[0034] The duty cycle correction device and synchronous acquisition system with the duty cycle correction device provided in this application embodiment include an input port, a signal processing module, a duty cycle correction module, and an output module. First, the signal processing module filters and blocks DC from the input signal received from the input port, effectively removing interference and DC components from the input signal and improving its quality. Then, the duty cycle correction module compares the processed input signal with a preset threshold value and corrects the duty cycle of the input signal based on the comparison result and the target duty cycle, obtaining a corrected output signal relative to the input signal. Finally, the output signal is sent to the system terminal through the output port. This application achieves the correction of an input signal with any duty cycle to any target duty cycle digitally, offering flexibility and reliability. Furthermore, it introduces a closed-loop feedback mechanism to further ensure the stability and accuracy of the output signal, thereby optimizing the overall system performance. Attached Figure Description
[0035] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.
[0036] Figure 1 This is a schematic diagram of the duty cycle correction device provided in one embodiment of this application.
[0037] Figure 2 This is a schematic diagram of the duty cycle correction device provided in another embodiment of this application.
[0038] Figure 3 This is a circuit diagram of a dynamic feedback module provided in one embodiment of this application.
[0039] Figure 4 This is a schematic diagram of the duty cycle correction device provided in another embodiment of this application.
[0040] Figure 5 This is a waveform diagram of the input signal during the duty cycle correction process provided in one embodiment of this application.
[0041] Figure 6 This is a schematic diagram of the duty cycle correction device provided in another embodiment of this application.
[0042] Figure 7 This is a circuit diagram of a bias superposition circuit provided in one embodiment of this application.
[0043] Figure 8 The waveform of the input signal during duty cycle correction is provided in another embodiment of this application.
[0044] Figure 9This is a schematic diagram of the structure of a synchronous acquisition system provided in one embodiment of this application.
[0045] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation
[0046] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. Similar elements in different embodiments are referred to by related similar element reference numerals. In the following embodiments, many details are described to facilitate a better understanding of the present application. However, those skilled in the art will readily recognize that some features may be omitted in different situations, or may be replaced by other elements, materials, or methods. In some cases, certain operations related to the present application are not shown or described in the specification. This is to avoid obscuring the core parts of the present application with excessive description. For those skilled in the art, detailed description of these related operations is not necessary; they can fully understand the related operations based on the description in the specification and general technical knowledge in the art.
[0047] Furthermore, the features, operations, or characteristics described in the specification can be combined in any suitable manner to form various embodiments. At the same time, the order of the steps or actions in the method description can be changed or adjusted in a manner obvious to those skilled in the art. Therefore, the various orders in the specification and drawings are only for the clear description of a particular embodiment and do not imply a necessary order, unless otherwise stated that a particular order must be followed.
[0048] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class, without limiting the number of objects; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship. Unless otherwise specified, the terms "connection" and "linkage" used in this application include both direct and indirect connections (linkages).
[0049] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.
[0050] Figure 1 This is a schematic diagram of the duty cycle correction device provided in one embodiment of this application. Figure 1 As shown, the duty cycle correction device provided in this embodiment includes at least an input port 110, a signal processing module 120, a duty cycle correction module 130, and an output port 140.
[0051] In this embodiment, input port 110 serves as the system interface, responsible for receiving input signals from external sources. The input signal can be a clock signal, which provides synchronization and controls the time interval between data acquisition and conversion, ensuring that data is acquired and converted at the correct time. Especially in systems with multiple devices working collaboratively, the clock signal helps ensure precise synchronization between devices, thereby avoiding data timing errors or loss of synchronization. However, clock signals may carry various noises and interferences, thus requiring further processing.
[0052] The signal processing module 120 is connected to the input port 110 and is responsible for performing signal processing on the received input signal, including at least filtering and DC blocking, to obtain the processed first signal. Specifically, the signal processing module 120 filters the input signal to remove high-frequency noise and spurious signals, and also performs DC blocking to eliminate the DC component in the signal, thereby obtaining a purer and more stable first signal.
[0053] Signal filtering selectively enhances or suppresses specific frequency components in a signal to eliminate interference or unwanted elements, reduce abrupt changes or random fluctuations, stabilize the signal, and preserve or enhance information at specific frequencies (such as edges and textures). This is commonly achieved using analog components such as resistors, capacitors, and inductors.
[0054] The core objective of DC blocking in signal processing is to eliminate the DC component while retaining the AC component. This plays a crucial role in protecting sensitive components, improving signal quality, power system stability, and testing and measurement. Common methods include using capacitors, inductors, or dedicated DC blockers to block the DC component while allowing the AC component to pass through.
[0055] In some embodiments, the signal processing module 120 includes at least a first low-pass filter 1201 and a signal DC blocker 1202 connected in sequence. The first low-pass filter 1201 is used to filter out high-frequency components in the input signal, reducing the steepness of the signal edges and making the edges of the input signal smoother. That is, by setting a cutoff frequency through the first low-pass filter 1201, signals below that frequency pass through with almost no loss, while signals above that frequency are significantly weakened or blocked; this is also known as "high-frequency removal filtering," achieving noise reduction, smoothing, and anti-interference of the input signal. The signal DC blocker 1202 is used to eliminate DC bias in the input signal while retaining AC bias, ensuring that the input signal is symmetrical around the zero axis and avoiding interference caused by zero-point drift.
[0056] In this embodiment, the duty cycle correction module 130 is connected to the signal processing module 120. It is responsible for acquiring the first signal, comparing the acquired first signal with a preset threshold, and correcting the duty cycle of the first signal based on the comparison result and the target duty cycle to obtain a corrected output signal relative to the input signal. Specifically, the duty cycle correction module 130 first acquires the first signal processed by the signal processing module 120, then precisely compares this signal with the preset threshold. Based on the comparison result and the target duty cycle set by the system, the duty cycle correction module 130 adjusts the first signal accordingly to ensure that its duty cycle meets the expected requirements, thereby obtaining a corrected output signal relative to the input signal.
[0057] The output port is connected to the duty cycle correction module 130. As the output end of the system, it is responsible for transmitting the corrected output signal stably and accurately to the connected terminal so that the terminal can meet its normal operation requirements based on the carefully processed and accurately duty cycle output signal received.
[0058] In summary, the duty cycle correction device provided in this embodiment includes an input port, a signal processing module, a duty cycle correction module, and an output module. Specifically, the signal processing module first filters and blocks DC from the input signal received from the input port, effectively removing interference and DC components from the input signal and improving signal quality. Then, the duty cycle correction module compares the processed input signal with a preset threshold value and corrects the duty cycle of the input signal based on the comparison result and the target duty cycle, obtaining a corrected output signal relative to the input signal. Finally, the output signal is sent to the system terminal through the output port, realizing dynamic adjustment of the input signal duty cycle and ensuring the stability and accuracy of the output signal, thereby optimizing the overall system performance.
[0059] Figure 2 This is a schematic diagram of the duty cycle correction device provided in another embodiment of this application. Figure 2As shown, the duty cycle correction device provided in this embodiment includes at least an input port 110, a signal processing module 120, a duty cycle correction module 130, and an output port 140. Compared with the above embodiment, it also includes a dynamic feedback module 150 connected between the output port and the duty cycle correction module 130.
[0060] In this embodiment, based on the above embodiment, the dynamic feedback module 150 first obtains the complete output signal of the previous duty cycle correction from the output port, extracts the DC component, compares the DC component with a reference signal, and generates dynamic feedback information based on the comparison result, which is then output to the duty cycle correction module 130. The duty cycle of the reference signal is the same as the target duty cycle; the dynamic feedback information includes at least one of threshold adjustment information and bias voltage adjustment information for the first signal.
[0061] Furthermore, the duty cycle correction module 130 is also used to adjust the threshold value and / or adjust the bias voltage of the first signal according to the dynamic feedback information, and to perform duty cycle correction on the first signal again to obtain the output signal after dynamic correction relative to the input signal and output it.
[0062] In other words, when performing duty cycle correction, the aforementioned duty cycle correction module 130 compares the acquired first signal with a preset threshold value, and corrects the duty cycle of the first signal based on the comparison result and the target duty cycle, obtaining a corrected output signal relative to the input signal. The dynamic feedback module 150 forms a closed-loop feedback link between the output port and the duty cycle correction module 130. By comparing the DC component of the corrected output signal with a reference signal, it generates dynamic feedback information based on the comparison result and outputs it to the duty cycle correction module 130. The dynamic feedback information includes threshold value adjustment information and / or bias voltage adjustment information for the first signal. This closed-loop feedback dynamically adjusts the processing prerequisites of the duty cycle correction module 130, constituting the duty cycle correction feedback mechanism. This dynamic feedback mechanism enables the duty cycle correction device to have self-optimization and adaptability capabilities. It can not only monitor the quality of the corrected output signal in real time, but also flexibly adjust key parameters based on feedback information, making the duty cycle correction more accurate, flexible, and efficient. This dynamic adjustment mechanism greatly improves the adaptability and stability of the device, ensuring that the corrected output signal always maintains high quality and stability, providing a solid guarantee for the normal operation of the entire system.
[0063] Figure 3 This is a circuit diagram of a dynamic feedback module provided in one embodiment of this application. Figure 3 As shown, the dynamic feedback module 150 provided in this embodiment includes at least a second low-pass filter 1501 and an operational amplifier 1502.
[0064] Specifically, the input terminal of the second low-pass filter 1501 is connected to the input terminal of the dynamic feedback module 150, that is, connected to the output port; the non-inverting input terminal of the operational amplifier 1502 is used to obtain the external input reference signal, the inverting input terminal of the operational amplifier 1502 is connected to the output terminal of the second low-pass filter 1501, and the output terminal of the operational amplifier 1502 is connected to the output terminal of the dynamic feedback module 150, that is, connected to the second input terminal of the duty cycle correction module 130.
[0065] The second low-pass filter 1501 is used to extract the DC component of the corrected output signal; the operational amplifier 1502 is used to output dynamic feedback information based on the comparison result between the DC component and the reference signal, and feed it back to the duty cycle correction module 130.
[0066] In some embodiments, when the DC component is greater than the reference signal, the operational amplifier 1502 outputs a first bias adjustment signal representing a reduction in the first signal bias voltage and / or a first threshold adjustment signal representing a reduction in the threshold value; when the DC component is less than the reference signal, the operational amplifier 1502 outputs a second bias signal representing an increase in the first signal bias voltage and / or a second threshold adjustment signal representing an increase in the threshold value.
[0067] Alternatively, when the DC component is greater than the reference signal, the operational amplifier 1502 outputs a first bias signal representing an increase in the first signal bias voltage and / or a first threshold adjustment signal representing an increase in the threshold value; when the DC component is less than the reference signal, the operational amplifier 1502 outputs a second bias signal representing a decrease in the first signal bias voltage and / or a second threshold adjustment signal representing a decrease in the threshold value.
[0068] Figure 4 This is a schematic diagram of the duty cycle correction device provided in another embodiment of this application. Figure 4 As shown, the duty cycle correction device provided in this embodiment is based on any of the above embodiments, and the duty cycle correction module 130 in the duty cycle correction device includes at least a shaping circuit 1301.
[0069] In this embodiment, the shaping circuit 1301 includes a first input terminal, a second input terminal, and an output terminal. Its first input terminal is connected to the output terminal of the signal processing module 120 and is used to acquire the first signal after filtering and DC blocking. Its second input terminal is connected to the output terminal of the dynamic feedback module 150 and is used to acquire the dynamic feedback information output by the dynamic feedback module 150. Its output terminal is connected to the output port and is used to output the output signal after real-time correction relative to the input signal.
[0070] The shaping circuit 1301 is used to compare the acquired first signal with a preset threshold, and to perform duty cycle correction on the first signal according to the comparison result and the target duty cycle, so as to obtain the output signal after correction relative to the input signal.
[0071] In some embodiments, when the first signal is higher than a threshold, the shaping circuit 1301 outputs a first level, and when the first signal is lower than the threshold, the shaping circuit 1301 outputs a second level, forming an output signal corrected relative to the input signal.
[0072] Alternatively, when the first signal is below the threshold, the shaping circuit 1301 outputs a first level; when the first signal is above the threshold, the shaping circuit 1301 outputs a second level, forming an output signal corrected relative to the input signal.
[0073] It should be noted that the first level and the second level are not the same; they are a set of relatively high and low levels. When the first level is high, the second level is low, and vice versa.
[0074] In some embodiments, the shaping circuit 1301 includes a threshold configuration unit (not shown in the figure). The threshold configuration unit is used to configure a preset threshold, or to configure a threshold based on dynamic feedback information. That is, the threshold configuration unit can be configured once or multiple times.
[0075] When the threshold configuration unit only supports single configuration, it can only configure the preset threshold. That is, during the duty cycle correction process of the shaping circuit 1301, the threshold remains unchanged. When the shaping circuit 1301 needs to adjust the feedback correction input signal in real time according to the dynamic feedback information, it can only perform duty cycle feedback correction according to the bias voltage adjustment information of the first signal in the dynamic feedback information.
[0076] When the threshold configuration unit supports multiple configurations, the shaping circuit 1301 needs to adjust the output signal after correction relative to the input signal in real time according to the dynamic feedback information. It can update the configured threshold according to the threshold adjustment information in the dynamic feedback information to complete the feedback correction of the input signal duty cycle. At the same time, it can also perform feedback correction of the input signal duty cycle according to the bias voltage adjustment information of the first signal in the dynamic feedback information.
[0077] In some embodiments, the shaping circuit 1301 includes any one of a Schmitt trigger, a comparator, a digital buffer, and an inverter.
[0078] Among them, Schmitt trigger comparators, digital buffers, and inverters can all adjust the threshold based on external circuits or set reference voltages in some scenarios.
[0079] Specifically, the hysteresis threshold of a Schmitt trigger can be indirectly adjusted via external circuitry. The comparator's threshold is determined by a reference voltage (Vref); adjusting the reference voltage changes the trigger threshold. Alternatively, an inverter or buffer with a fixed threshold can be used, and the effective threshold can be adjusted via a pre-divider circuit.
[0080] Figure 5 This is a waveform diagram of the input signal during duty cycle correction according to one embodiment of this application. Based on Figure 4 The duty cycle correction device structure shown is as follows. Figure 5 The changes in the input signal during each process of duty cycle correction are presented.
[0081] like Figure 5 As shown, the external input signal is a square wave signal. This input signal is transmitted to the first low-pass filter 1201. After the first low-pass filter 1201 filters out most of the high-frequency noise and spurious waves, the rising and falling edges of the input signal become slower, and the input signal changes from a square wave to a smooth ramp wave. The filtered input signal is then transmitted to the signal DC blocker 1202 for DC blocking, eliminating the DC component in the signal. It can be seen that the input signal is symmetrical about the zero axis at this time. The DC-blocked input signal is then transmitted to the shaping circuit 1301. The further processed input signal is precisely compared with a preset threshold. According to the preset comparison rules, when the processed input signal is higher than the threshold, the shaping circuit 1301 outputs a high level; when the processed input signal is lower than the threshold, the shaping circuit 1301 outputs a low level. After shaping, a corrected output signal relative to the input signal is formed. It can be seen that the processed input signal is now restored to a square wave, and the duty cycle of the final output signal has changed compared to the input signal.
[0082] At this time, the dynamic feedback module 150 receives the output signal from the output port, extracts the DC component therein and compares it with the reference signal, determines the threshold adjustment information based on the comparison result, and outputs it to the duty cycle correction module 130, thereby entering the dynamic feedback adjustment mechanism; the threshold configuration unit in the shaping circuit 1301 responds to the adjustment signal corresponding to the threshold adjustment information and adjusts the previously configured threshold; the input signal (first signal) after filtering and DC blocking is compared with the updated and adjusted threshold again, and according to the preset comparison rules, the shaped output is the output signal corrected relative to the input signal.
[0083] It should be noted that, Figure 5The threshold value in the data is a preset threshold value, which is also the threshold value adjusted according to the dynamic feedback module 150.
[0084] Figure 6 This is a schematic diagram of the duty cycle correction device provided in another embodiment of this application. Figure 6 As shown, the duty cycle correction device provided in this embodiment is based on any of the above embodiments. The duty cycle correction module 130 in the duty cycle correction device includes at least a shaping circuit 1301 and a bias superposition circuit 1302.
[0085] In this embodiment, the bias superposition circuit 1302 includes a first input terminal, a second input terminal, and an output terminal. Its first input terminal is connected to the output terminal of the signal processing module 120 to acquire a first signal that has undergone filtering and DC blocking. Its second input terminal is connected to the output terminal of the dynamic feedback module 150 to acquire the dynamic feedback information output by the dynamic feedback module 150. The shaping circuit 1301 includes an input terminal and an output terminal. Its input terminal is connected to the output terminal of the bias superposition circuit 1302, and its output port is connected to output a real-time corrected output signal relative to the input signal.
[0086] After receiving the bias adjustment information representing the first signal from the dynamic feedback information, the bias superposition circuit 1302 adjusts the bias voltage of the first signal according to the bias adjustment information and transmits the adjusted first signal to the shaping circuit 1301. The shaping circuit 1301 is responsible for comparing the first signal after bias voltage adjustment with a preset threshold value, and correcting the duty cycle of the first signal after bias voltage adjustment according to the comparison result and the target duty cycle, and finally obtaining the output signal corrected relative to the input signal.
[0087] In some embodiments, when the first signal is higher than a threshold, the shaping circuit 1301 outputs a first level, and when the first signal is lower than the threshold, the shaping circuit 1301 outputs a second level, forming an output signal corrected relative to the input signal.
[0088] Alternatively, when the first signal is below the threshold, the shaping circuit 1301 outputs a first level; when the first signal is above the threshold, the shaping circuit 1301 outputs a second level, forming an output signal corrected relative to the input signal.
[0089] Figure 7 This is a circuit diagram of a bias superposition circuit provided in one embodiment of this application. Figure 7 As shown, the bias superposition circuit 1302 provided in this embodiment includes at least a damping resistor R1 and a filter capacitor C1 connected in series.
[0090] Specifically, the first end of the damping resistor R1 is connected to the first input terminal of the bias superposition circuit 1302, that is, connected to the output terminal of the signal processing module 120, for receiving the first signal; the second end of the damping resistor R1 is connected to the second input terminal of the bias superposition circuit 1302, that is, connected to the output terminal of the dynamic feedback module 150, for obtaining the bias adjustment information representing the first signal in the dynamic feedback information; the first end of the filter capacitor C1 is connected to the first end of the damping resistor R1; and the second end of the filter capacitor C1 is connected to the preset voltage terminal, that is, connected to the ground terminal.
[0091] Figure 8 The waveform of the input signal during duty cycle correction is provided in another embodiment of this application. Based on Figure 6 The duty cycle correction device structure shown is as follows. Figure 8 The changes in the input signal during each process of duty cycle correction are presented.
[0092] like Figure 8 As shown, the external input signal is a square wave signal. This input signal is transmitted to the first low-pass filter 1201. After the first low-pass filter 1201 filters out most of the high-frequency noise and spurious waves, the rising and falling edges of the input signal become slower, and the input signal changes from a square wave to a smooth ramp wave. The filtered input signal is then transmitted to the signal DC blocker 1202 for DC blocking, eliminating the DC component in the signal. It can be seen that the input signal is symmetrical about the zero axis at this time. The DC-blocked input signal is then transmitted to the shaping circuit 1301. The further processed input signal is precisely compared with a preset threshold. According to the preset comparison rules, when the processed input signal is higher than the threshold, the shaping circuit 1301 outputs a high level; when the processed input signal is lower than the threshold, the shaping circuit 1301 outputs a low level. After shaping, a corrected output signal relative to the input signal is formed. It can be seen that the processed input signal is now restored to a square wave, and the duty cycle of the final output signal has changed compared to the input signal.
[0093] At this time, the dynamic feedback module 150 receives the output signal from the output port, extracts the DC component and compares it with the reference signal, determines the bias voltage adjustment information for the first signal (the input signal after filtering and DC blocking) based on the comparison result, and outputs it to the duty cycle correction module 130, thereby entering the dynamic feedback adjustment mechanism; the bias superposition circuit 1302 responds to the adjustment signal corresponding to the bias voltage adjustment information of the first signal, and adjusts the bias voltage of the first signal (waveform shifting up or down); the first signal after bias adjustment is compared with the preset threshold again, and the output signal after correction relative to the input signal is shaped and output according to the preset comparison rules.
[0094] It should be noted that, Figure 8 The threshold value in the text is a preset threshold value. Figure 8 In the schematic waveform diagram, the threshold value configured in the shaping circuit 1301 remains unchanged.
[0095] In other embodiments, during the duty cycle correction of the input signal, the following steps can also be taken: the dynamic feedback module 150 receives the output signal from the output port, extracts the DC component therein and compares it with the reference signal, determines the threshold adjustment information and the bias voltage adjustment information for the first signal based on the comparison result, and outputs them to the shaping circuit 1301 and the bias superposition circuit 1302 respectively. The shaping circuit 1301 and the bias superposition circuit 1302 make corresponding adjustments to the threshold and the first signal respectively. Finally, the first signal after bias adjustment is compared with the adjusted threshold again, and the output signal after correction relative to the input signal is shaped and output according to the preset comparison rules.
[0096] In summary, the duty cycle correction device provided in any of the above embodiments corrects an input signal with any duty cycle to an arbitrary target duty cycle in a digital manner, which is flexible and reliable. At the same time, a closed-loop feedback mechanism is introduced to further ensure the stability and accuracy of the output signal, thereby optimizing the overall system performance.
[0097] Figure 9 This is a schematic diagram of the structure of a synchronous acquisition system provided in one embodiment of this application. Figure 9 As shown, the synchronous acquisition system of this embodiment includes multiple cascaded signal acquisition devices 910 and a duty cycle correction device 920 as described in any of the above embodiments, which is installed in each signal acquisition device 910.
[0098] In this embodiment, multiple cascaded signal acquisition devices 910 are cascaded in a daisy chain manner. The synchronous acquisition system requires a synchronous clock signal, and the clock signal needs to maintain the same duty cycle.
[0099] The externally input clock signal is input to the clock signal input terminal of the first-level signal acquisition device 910. After being buffered by the local signal acquisition device 910, it is transmitted to the next-level signal acquisition device 910. That is, the clock signal of the clock signal input terminal of each other-level signal acquisition device 910 comes from the clock signal of the previous-level signal acquisition device 910.
[0100] The duty cycle correction device 920 in each level of the synchronous acquisition system is used to correct the duty cycle of the clock signal of the synchronous acquisition system at that level. That is, the duty cycle correction device 920 in each level of signal acquisition device 910 is used to correct the duty cycle of the clock signal received by the signal acquisition device 910 at that level according to the target duty cycle, so that the clock signal received by each level of signal acquisition device 910 remains synchronized and has the same duty cycle.
[0101] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art, under the guidance of this application, can make several simple deductions, modifications or substitutions based on the spirit of this application and the scope of protection of the claims without departing from the spirit of this application and the claims. All of these are within the protection scope of this application.
Claims
1. A duty cycle correction device, characterized in that, include: Input port, used to receive input signals; A signal processing module, connected to the input port, is used to filter and block DC from the received input signal to obtain a processed first signal; A duty cycle correction module, connected to the signal processing module, is used to acquire the first signal, compare the acquired first signal with a preset threshold, and perform duty cycle correction on the first signal according to the comparison result and the target duty cycle to obtain an output signal corrected relative to the input signal. The output port is connected to the duty cycle correction module and is used to output the corrected output signal to the connected terminal.
2. The duty cycle correction device according to claim 1, characterized in that, It also includes a dynamic feedback module connected between the output port and the duty cycle correction module; The dynamic feedback module is used to extract the DC component of the corrected output signal, compare the DC component with a reference signal, and generate dynamic feedback information based on the comparison result and output it to the duty cycle correction module. The duty cycle of the reference signal is the same as that of the target signal; The dynamic feedback information includes at least one of the threshold adjustment information and the bias voltage adjustment information of the first signal; The duty cycle correction module is also used to adjust the threshold value and / or adjust the bias voltage of the first signal according to the dynamic feedback information, and to perform duty cycle correction on the first signal again to obtain the dynamically corrected output signal and output it.
3. The duty cycle correction device according to claim 2, characterized in that, The duty cycle correction module includes at least a shaping circuit; the first input terminal of the shaping circuit is connected to the output terminal of the signal processing module, the second input terminal of the shaping circuit is connected to the output terminal of the dynamic feedback module, and the output terminal of the shaping circuit is connected to the output port. Specifically, when the first signal is higher than the threshold, the shaping circuit outputs a first level; when the first signal is lower than the threshold, the shaping circuit outputs a second level. Alternatively, when the first signal is below the threshold, the shaping circuit outputs a first level; when the first signal is above the threshold, the shaping circuit outputs a second level.
4. The duty cycle correction device according to claim 3, characterized in that, The shaping circuit includes a threshold configuration unit; the threshold configuration unit is used to configure a preset threshold or to configure a threshold based on the threshold represented by the dynamic feedback information.
5. The duty cycle correction device according to claim 4, characterized in that, The shaping circuit includes any one of a Schmitt trigger, a comparator, a digital buffer, and an inverter.
6. The duty cycle correction device according to claim 3, characterized in that, The duty cycle correction module includes a bias superposition circuit; the first input terminal of the bias superposition circuit is connected to the output terminal of the signal processing module, and the second input terminal of the bias superposition circuit is connected to the output terminal of the dynamic feedback module; the input terminal of the shaping circuit is connected to the output terminal of the bias superposition circuit, and the output terminal of the shaping circuit is connected to the output port. The bias superposition circuit is used to adjust the bias voltage of the first signal according to the bias adjustment information characterizing the first signal in the dynamic feedback information, and output the adjusted first signal.
7. The duty cycle correction device according to claim 6, characterized in that, The bias superposition circuit includes at least a damping resistor and a filter capacitor connected in series. The first end of the damping resistor is connected to the first input terminal of the bias superposition circuit, and the second end of the damping resistor is connected to the second input terminal of the bias superposition circuit; the second end of the filter capacitor is connected to the preset voltage terminal.
8. The duty cycle correction device according to any one of claims 2-7, characterized in that, The dynamic feedback module includes at least a second low-pass filter and an operational amplifier; the second low-pass filter is used to extract the DC component of the corrected output signal; the operational amplifier is used to output dynamic feedback information based on the comparison result of the DC component and the reference signal. The input terminal of the second low-pass filter is connected to the input terminal of the dynamic feedback module; the non-inverting input terminal of the operational amplifier is used to acquire the reference signal, the inverting input terminal of the operational amplifier is connected to the output terminal of the second low-pass filter, and the output terminal of the operational amplifier is connected to the output terminal of the dynamic feedback module. Wherein, when the DC component is greater than the reference signal, the operational amplifier outputs a first bias adjustment signal representing a reduction in the bias voltage of the first signal and / or a first threshold adjustment signal representing a reduction in the threshold value; when the DC component is less than the reference signal, the operational amplifier outputs a second bias signal representing an increase in the bias voltage of the first signal and / or a second threshold adjustment signal representing an increase in the threshold value. Alternatively, when the DC component is greater than the reference signal, the operational amplifier outputs a first bias signal representing an increase in the bias voltage of the first signal and / or a first threshold adjustment signal representing an increase in the threshold value; when the DC component is less than the reference signal, the operational amplifier outputs a second bias signal representing a decrease in the bias voltage of the first signal and / or a second threshold adjustment signal representing a decrease in the threshold value.
9. The duty cycle correction device according to claim 1, characterized in that, The signal processing module includes at least a first low-pass filter and a DC blocking device connected in sequence; the first low-pass filter is used to filter out high-frequency components in the input signal to smooth the edges of the input signal; the DC blocking device is used to eliminate DC bias in the input signal to make the input signal symmetrical about the zero axis.
10. A synchronous acquisition system, characterized in that, It includes multiple cascaded signal acquisition devices and a duty cycle correction device as described in any one of claims 1-9, which is installed in each signal acquisition device; Among them, the clock signal input terminal of the first-level signal acquisition device is used to acquire the externally input clock signal, and the clock signal of the clock signal input terminal of each other signal acquisition device comes from the clock signal of the previous level signal acquisition device. The duty cycle correction device in each level of signal acquisition equipment is used to correct the duty cycle of the clock signal received by the signal acquisition equipment at this level according to the target duty cycle, so as to keep the clock signal received by each level of signal acquisition equipment synchronized.