A high-voltage pulse reflection signal processing circuit

Abstract

The application relates to a high-voltage pulse reflection signal processing circuit. It mainly comprises a pulse generation circuit, a high-voltage switch circuit, a switch control circuit and a high-speed signal isolation circuit; the pulse generation circuit is used for generating a high-voltage transmitting pulse and transmitting the high-voltage transmitting pulse to the high-voltage switch circuit; the switch control circuit and the pulse generation circuit are both controlled by a host computer; when the pulse generation circuit generates the high-voltage transmitting pulse, the switch control circuit controls the high-voltage switch circuit to inhibit the high-voltage transmitting pulse waveform according to a control signal of the host computer; after the generation of the high-voltage transmitting pulse is completed, the switch control circuit controls the high-voltage switch circuit to allow low-voltage reflection signals to pass according to the control signal of the host computer; the high-speed signal isolation circuit is used for receiving the low-voltage reflection signals output by the high-voltage switch circuit and isolating and outputting the low-voltage reflection signals to a downstream acquisition circuit. The application can solve the technical problem that the high-voltage transmitting pulse can easily cause damage to a receiving circuit when a single crystal transducer is multiplexed.

Description

Technical Field

[0001] This application relates to the field of high-voltage pulse signal processing technology, and in particular to a high-voltage pulse reflection signal processing circuit. Background Technology

[0002] Using crystal transducers to generate pulses and measuring distances by the time difference of reflected waveforms is a common technique in the field of acoustic measurement.

[0003] In existing technologies, to avoid interference from the transmitted pulse to the received reflected signal, the industry conventionally uses two crystal transducers to handle the transmitted pulse and received reflected waveforms separately, thus achieving physical isolation between transmission and reception. However, in scenarios with requirements for miniaturization of equipment size and weight, or higher requirements for measurement accuracy, it is necessary to use a single crystal transducer to handle both the output of the high-voltage transmitted pulse and the reception of the low-voltage reflected signal. This design of multiplexing a single crystal transducer results in the high-voltage transmitted pulse and the low-voltage reflected signal being transmitted to the receiving circuit together. The high-voltage transmitted pulse signal can directly burn out the delicate receiving processing chip, becoming a core technical obstacle to the implementation of the single crystal transducer multiplexing design. Furthermore, the transmitted pulse is usually a narrow pulse width, high peak-to-peak value, and high-energy signal. Traditional transient suppression circuits are prone to causing secondary damage when suppressing it, failing to solve the signal aliasing and chip burning problem under single crystal transducer multiplexing.

[0004] Therefore, how to overcome the technical problem that high-voltage transmission pulses can easily damage the receiving circuit when single-crystal transducers are reused in the prior art is a problem to be solved in this technical field. Summary of the Invention

[0005] To address the aforementioned deficiencies or improvement needs of existing technologies, and to solve the technical problem that high-voltage transmission pulses can easily damage the receiving circuit when a single crystal transducer is reused, this application provides a high-voltage pulse reflection signal processing circuit. It adopts a host computer-coordinated timing control design, integrating four core modules: a pulse generation circuit, a high-voltage switching circuit, a switch control circuit, and a high-speed signal isolation circuit. This allows the switch control circuit and pulse generation circuit to be uniformly and collaboratively controlled by the host computer. During the pulse generation phase, the switch control circuit controls the high-voltage switching circuit to perform voltage division and suppression of the high-voltage transmission pulse, preventing the high-voltage signal from entering the receiving end. After the pulse ends, the switch control circuit opens, allowing the low-voltage reflected signal to pass through the high-voltage switching circuit with low loss. Simultaneously, the high-speed signal isolation circuit achieves isolated signal output, realizing precise suppression of the high-voltage transmission pulse and effective transmission of the low-voltage reflected signal at the circuit level. Ultimately, this achieves a multiplexing design where the same crystal transducer completes both transmission and reception. Furthermore, the power supply isolation and signal isolation designs between modules further ensure the stability of the circuit operation and the accuracy of signal transmission.

[0006] Meanwhile, to further optimize circuit performance, a power supply control circuit for the pulse processing circuit is added to enable controllable power on / off of the pulse processing module. A low-voltage power supply boost circuit is added to provide an appropriate operating voltage for the switch control and high-speed signal isolation circuits. Differentiated physical isolation is implemented for the input power supply, processing circuit power supply, and output power supply. The power MOSFETs of the high-voltage switching circuit utilize their on / off characteristics under different states to achieve high-voltage suppression. Optocoupler isolation units are designed for the switch control circuit, and insulated gate units are designed for the high-speed signal isolation circuit, forming a complete closed-loop circuit system of "generation-control-isolation-acquisition".

[0007] The embodiments of this application adopt the following technical solutions: This application provides a high-voltage pulse reflection signal processing circuit, including a pulse generation circuit, a high-voltage switching circuit, a switching control circuit, and a high-speed signal isolation circuit; The pulse generation circuit is used to generate a high-voltage transmission pulse and transmit it to the high-voltage switching circuit, which is connected to the crystal transducer. Both the switch control circuit and the pulse generation circuit are controlled collaboratively by the host computer. When the pulse generation circuit generates a high-voltage transmission pulse, the switch control circuit controls the high-voltage switch circuit according to the host computer control signal to suppress the high-voltage transmission pulse waveform without causing a sudden change in the voltage at the switch tube. After the high-voltage transmission pulse is generated, the switch control circuit controls the high-voltage switch circuit according to the host computer control signal to allow the low-voltage reflected signal to pass through. The high-speed signal isolation circuit is used to receive the low-voltage reflected signal output by the high-voltage switching circuit and isolate the low-voltage reflected signal to the downstream acquisition circuit.

[0008] By adopting the above technical solution, the host computer coordinates the timing control of the pulse generation circuit and the switch control circuit, accurately realizing waveform suppression in the high-voltage transmission pulse stage and unobstructed transmission in the low-voltage reflection signal stage. At the same time, the high-speed signal isolation circuit completes the isolation output of the reflection signal, effectively solving the problem of high-voltage pulse and low-voltage reflection signal aliasing and burning out the receiving chip when a single crystal transducer is multiplexed. It successfully realizes the multiplexing function of the same crystal transducer for both high-voltage transmission pulse output and low-voltage reflection signal reception, meeting the design requirements of miniaturization and high precision of the equipment.

[0009] In some embodiments, a low-voltage power supply boost circuit is also included, which is used to provide an appropriate operating voltage for the switch control circuit and the high-speed signal isolation circuit. The low-voltage power supply boost circuit is a boost circuit.

[0010] By adopting the above technical solution and adding a low-voltage power supply boost circuit for the boost topology, a suitable operating voltage can be provided for the switch control circuit and the high-speed signal isolation circuit. This solves the problem that the conventional 3.3V power supply cannot meet the operating voltage requirements of the relevant circuits, ensuring the stable and normal operation of the switch control circuit and the high-speed signal isolation circuit, and providing voltage support for the signal processing accuracy and operational reliability of the entire circuit system.

[0011] In some embodiments, a pulse processing circuit power supply control circuit is also included. The pulse processing circuit power supply control circuit is controlled by a host computer and provides a controllable operating power supply for the high-voltage switching circuit, the low-voltage power supply boost circuit, and the high-speed signal isolation circuit. When the host computer sends a pulse generation signal, the pulse processing circuit power supply control circuit is turned on to supply power. When the host computer does not send a pulse generation signal, the pulse processing circuit power supply control circuit is turned off to cut off power.

[0012] By adopting the above technical solution, a power supply control circuit for pulse processing circuit controlled by the host computer is added, which realizes the controllable power on and off of the high-voltage switching circuit, low-voltage power supply boost circuit and high-speed signal isolation circuit. The power supply is turned on only when the host computer sends a pulse signal, and the power is turned off when there is no pulse signal. This effectively reduces the overall power consumption of the circuit system, and avoids circuit malfunctions in the absence of a signal, further improving the stability and energy efficiency of the circuit operation.

[0013] In some embodiments, the input power supply of the high-voltage pulse reflection signal processing circuit includes four power supplies: 3.3V / GND, HV / GND, 3.6V ISO / SGND, and 3.3V_receive / AGND. There is no electrical isolation between 3.3V / GND and HV / GND, while the other power supplies are physically isolated from each other. The 3.3V / GND supply power to the transmitting side of the pulse generation circuit and the switch control circuit, and also supplies power to the host computer; the HV / GND provides high voltage for the pulse generation circuit, working in conjunction with 3.3V / GND to generate high-voltage transmission pulses; the 3.6VISO / SGND is the main power supply for the pulse processing circuit power control circuit, which, after circuit conversion, provides operating power to the processing side of the high-voltage switch circuit, the low-voltage power supply boost circuit, and the high-speed signal isolation circuit; the 3.3V_receive / AGND supplies power to the receiving side of the high-speed signal isolation circuit, providing a suitable power environment for the isolated signal output to the acquisition circuit.

[0014] By adopting the above technical solution, the power supply distribution and isolation design rules for the four external input power supplies are clarified, realizing the non-isolated adaptation between the transmitting power supply and the high-voltage power supply, and the physical isolation of the other power supplies. This not only ensures the high-voltage power supply requirements of core modules such as the pulse generation circuit, but also effectively avoids electrical crosstalk between different power supplies. At the same time, each circuit module is allocated a dedicated and adapted power supply to ensure that each module works accurately and stably, and eliminates the problem of aliasing of switching quantities, pulse signals and acquisition signals from the power supply level.

[0015] In some embodiments, the pulse generation circuit includes a CMOS amplifier unit and a power MOSFET Q5. The narrow pulse sent by the host computer is amplified by the CMOS amplifier unit to enhance the output capability and then controls the switching on and off of the power MOSFET Q5. When the power MOSFET Q5 is on, it outputs high voltage to the high voltage switching circuit. When the power MOSFET Q5 is off, it releases charge through a diode to achieve a rapid voltage drop, thus completing the generation of the high voltage transmission pulse.

[0016] By adopting the above technical solution, the core components and working principle of the pulse generation circuit are precisely designed. The CMOS amplification unit is used to improve the narrow pulse output capability of the host computer. The switching of the power MOSFET Q5 and the diode discharge are used to realize the rapid generation and rapid voltage drop of the high voltage transmission pulse, which ensures the narrow pulse width and peak-to-peak output characteristics of the high voltage transmission pulse. At the same time, the pulse generation process is made faster and more controllable, which is suitable for the pulse transmission requirements of acoustic measurement.

[0017] In some embodiments, the high-voltage switching circuit includes a transformer and a power MOSFET Q1. The primary side of the transformer is connected to a pulse generation circuit, and the secondary side is connected to a crystal transducer. The control signal CTL2 output by the switching control circuit controls the operating state of the power MOSFET Q1 in the high-voltage switching circuit. During the high-voltage pulse transmission phase, the power MOSFET Q1 operates in the cutoff region, and the high-voltage pulse is output after being divided by a large resistor. During the low-voltage reflected signal phase, the power MOSFET Q1 operates in the linear region, and the low-voltage reflected signal is output after being divided by a small resistor.

[0018] By adopting the above technical solution, the core components of the high-voltage switching circuit and the state-by-state operation mode of the power MOSFET Q1 are designed. A transformer is used to realize the pulse transmission and connection with the crystal transducer. By using the staged operation of the MOSFET's cutoff region and linear region in conjunction with the voltage division by the resistor, the high-voltage transmission pulse is effectively stepped down and the low-voltage reflected signal is transmitted with low loss. Moreover, the MOSFET does not directly turn off or turn on the high voltage, which fundamentally avoids the arcing phenomenon caused by the switching transistor turning off the high voltage in traditional switching circuits, thereby improving the circuit's service life and operational stability.

[0019] In some implementations, the amplitude of the high-voltage transmission pulse is reduced to 1.9-2.1V after being divided by a large resistor, and the preset threshold is 4.9-5.1V.

[0020] By adopting the above technical solution, the amplitude of the high voltage after voltage division and the high voltage suppression threshold under fault conditions are precisely limited. The high voltage transmission pulse is stably controlled at around 2V after voltage division, which not only achieves effective suppression of high voltage, but also avoids excessive voltage division from affecting subsequent signal transmission. At the same time, the fault high voltage is precisely suppressed to around 5V, ensuring the safety of each module of the circuit under abnormal conditions. This makes the high voltage suppression effect of the circuit more quantifiable and controllable, and improves the accuracy of the implementation of the technical solution.

[0021] In some embodiments, the switch control circuit includes an optocoupler isolation unit for receiving control signals from the host computer and outputting control signal CTL2 to the high-voltage switch circuit; the operating voltage of the switch control circuit is provided by a low-voltage power supply boost circuit to ensure that the gate-source voltage Vgs of the power MOSFET Q1 in the high-voltage switch circuit is greater than the gate turn-on voltage Vth.

[0022] By adopting the above technical solution, an optocoupler isolation unit is added to the switch control circuit, which not only realizes the stable transmission of the host computer control signal and the accurate output of the CTL2 control signal, but also achieves electrical isolation of the control signal, avoiding crosstalk of the control signal by the high voltage on the transmitting side; at the same time, the low-voltage power supply boost circuit provides an adaptation voltage for the switch control circuit, ensuring that the gate-source voltage Vgs of the power MOSFET Q1 is greater than the turn-on voltage Vth, ensuring that the MOSFET Q1 can accurately enter the linear region to achieve the smooth passage of the low-voltage reflected signal, thereby improving the control accuracy and reliability of the switch control circuit.

[0023] In some embodiments, the high-speed signal isolation circuit includes an insulating gate unit. The input of the insulating gate unit is powered by the processing-side power supply 5VISO / SGND, and the output is powered by the receiving-side power supply 3.3V_receive / AGND. After the signal output from the high-voltage switching circuit is divided and boosted to the midpoint voltage, the insulating gate unit achieves electrical isolation between the processing side and the receiving side, and outputs a signal with the same ground as the receiving side to the acquisition circuit.

[0024] By adopting the above technical solution, the core components and working mode of the high-speed signal isolation circuit are designed. The insulating gate unit is used to achieve electrical isolation between the processing side and the receiving side. With the separate power supply of 5VISO / SGND and 3.3V_receive / AGND, electrical crosstalk between the high-voltage processing side and the low-voltage receiving side is completely avoided. At the same time, the signal voltage is boosted to the midpoint voltage through signal voltage division to achieve signal level adaptation. The standard signal with the same ground as the receiving side is output to the acquisition circuit, which ensures that the reflected signal received by the acquisition circuit is pure and accurate, effectively solves the signal aliasing problem, and improves the acquisition accuracy of the reflected signal.

[0025] In summary, this application includes at least the following beneficial technical effects: 1. The technical problem of high-voltage transmission pulses easily damaging the receiving circuit when a single crystal transducer is reused has been solved. Through the coordinated timing control of the host computer and the voltage division suppression design of the high-voltage switching circuit, the high-voltage transmission pulse is accurately suppressed (to about 2V) without affecting the normal transmission of the low-voltage reflected signal. The transmission and reception multiplexing of the same crystal transducer has been successfully realized, meeting the design requirements of miniaturization and high precision of the equipment. 2. The power MOSFET in the high-voltage switching circuit never directly turns off or on the high voltage, which fundamentally avoids the arcing phenomenon caused by the switching transistor turning off the high voltage in traditional switching circuits, thus improving the working stability and service life of the circuit. 3. Through a two-stage isolation design of "physical power isolation + high-speed signal isolation", the aliasing problem of switching signals, high voltage pulses and acquisition signals is completely avoided, ensuring the accuracy of reflected signal acquisition. At the same time, electrical isolation between the processing side and the receiving side is achieved, protecting the precision acquisition chip. 4. The added power supply control circuit enables controllable power on and off of the pulse processing module. When no pulse is generated, the module is powered off, effectively reducing the overall power consumption of the circuit. The boost circuit provides an appropriate voltage for the switch control and isolation circuit, ensuring the normal operation of the power MOSFET and improving the overall adaptability of the circuit system. 5. The entire circuit system is a modular closed-loop design, with each module functioning collaboratively and timing-matched. It has a compact structure, is easy to integrate and debug, and can be widely used in miniaturized, high-precision instruments that use the pulse reflection principle, such as acoustic measurement and ranging, thus expanding the application scenarios of the technology. Attached Figure Description

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

[0027] Figure 1 A schematic diagram of the pulse generation circuit provided in this application; Figure 2 This is a schematic diagram of the high-voltage switch circuit provided in this application; Figure 3 A schematic diagram of the power supply control circuit for the pulse processing circuit provided in this application; Figure 4 This is a schematic diagram of the low-voltage power supply boost circuit provided in this application; Figure 5 A schematic diagram of the switch control circuit provided in this application; Figure 6 A schematic diagram of the high-speed signal isolation circuit provided in this application. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application. Furthermore, the technical features involved in the various embodiments described below can be combined with each other as long as they do not conflict with each other. The application will now be described in detail with reference to the accompanying drawings and embodiments.

[0029] This application provides a high-voltage pulse reflection signal processing circuit, which aims to achieve multiplexing of high-voltage transmission pulse output and low-voltage reflection signal reception of the same crystal transducer, effectively solving the technical problem of high-voltage pulse and low-voltage reflection signal aliasing, while avoiding problems such as switching transistor arcing and signal aliasing.

[0030] Overall, the high-voltage pulse reflection signal processing circuit of this application embodiment includes six core modules: pulse generation circuit, high-voltage switching circuit, switching control circuit, high-speed signal isolation circuit, low-voltage power supply boost circuit, and pulse processing circuit power supply control circuit. The external input power supply of the circuit consists of four channels: 3.3V / GND, HV / GND, 3.6VISO / SGND, and 3.3V_receive / AGND. Internally, it converts the input power supply to generate two working power supplies: 3.6V' and 5VISO / SGND. Each module is controlled by the host computer. The timing of the pulse generation circuit and the switching control circuit is precisely matched. The high-voltage switching circuit is directly connected to the crystal transducer. The output of the high-speed signal isolation circuit is connected to the downstream acquisition circuit, forming a complete signal processing link of "pulse generation - high-voltage suppression - reflected signal transmission - isolation output - acquisition".

[0031] In some implementations, the external input power supply consists of four channels: 3.3V / GND, HV / GND, 3.6V ISO / SGND, and 3.3V_receive / AGND, with differentiated isolation between the power supplies. 3.3V / GND: This is a dedicated power supply for the transmitting section, providing power to the transmitting side of the pulse generation circuit and the switch control circuit, and also providing operating power to the host computer. This power supply has no electrical isolation from HV / GND, and is suitable for generating high-voltage transmitting pulses. HV / GND: This is the high-voltage power supply for transmission, providing high voltage for the pulse generation circuit only. The high-voltage transmission pulse is generated by the MOS switch controlled by the pulse signal. 3.6VISO / SGND: This is a dedicated isolated power supply for the pulse processing section. It serves as the main power supply for the pulse processing circuit's power control circuit. After being converted to 3.6V by this circuit, it supplies power to the processing side of the high-voltage switching circuit, the low-voltage power supply boost circuit, and the high-speed signal isolation circuit. 3.3V_receive / AGND: This is a dedicated isolated power supply for the receiving side, providing power only to the receiving side of the high-speed signal isolation circuit. It provides a suitable power environment for the isolated low-voltage reflected signal output to the acquisition circuit. Among the four input power supplies mentioned above, except for 3.3V / GND and HV / GND which have no electrical isolation, all other power supplies are physically isolated to avoid the situation where electrical crosstalk between different power supplies threatens the stability of downstream circuits due to transmission interference, and to prevent the aliasing of switching signals, pulse signals and acquisition signals.

[0032] The pulse generation circuit, high-voltage switching circuit, switching control circuit, high-speed signal isolation circuit, low-voltage power supply boost circuit, and pulse processing circuit power supply control circuit are described below.

[0033] refer to Figure 1 As shown, in some embodiments, the pulse generation circuit includes a CMOS amplifier unit and a power MOSFET Q5, which is directly controlled by the host computer. Its core function is to generate a high-voltage transmission pulse with a narrow pulse width and high peak-to-peak value. The working process is as follows: The extremely narrow pulse signal sent by the host computer is first amplified by a pair of CMOS amplifier units to enhance the output capability. The amplified signal is used to control the switching on and off of the power MOSFET Q5. When the gate voltage of the power MOSFET Q5 is high, its T6' pin is connected to ground, and its T4' pin is high voltage, directly outputting high voltage to the primary side of the transformer in the high-voltage switching circuit. When the gate voltage of the power MOSFET Q5 is low, its pin is floating. The primary side of the transformer in the high-voltage switching circuit is equivalent to a freewheeling inductor. The current flowing through it releases charge through the diode, ensuring that the voltage can drop rapidly. This completes the generation process of a high-voltage transmission pulse.

[0034] refer to Figure 2 As shown, in some embodiments, the high-voltage switching circuit includes a transformer and a power MOSFET Q1. The primary side of the transformer is connected to the pulse generation circuit, and the secondary side is directly connected to the crystal transducer. Its core function is to suppress the high-voltage transmitted pulse and transmit the low-voltage reflected signal with low loss under the control of the CTL2 signal of the switching control circuit. Its operation is divided into two stages, and the power MOSFET Q1 is never directly turned off or on to prevent arcing from the source. 1. High-voltage transmit pulse stage: The control signal CTL2 is pulled to a low level before the control signal of the pulse generation circuit is set to 1, ensuring that the power MOSFET Q1 enters the cutoff region in advance. The high-voltage transmit pulse generated by the pulse generation circuit is transmitted through the transformer and then the amplitude is reduced to about 2V by the voltage divider of the large resistor before being output, thus achieving effective suppression of the high-voltage pulse and preventing the high-voltage signal from being introduced into the subsequent circuit. 2. Low-voltage reflection signal stage: The control signal CTL2 is pulled high later than the control signal of the pulse generation circuit, ensuring that the power MOSFET Q1 enters the linear region with a delay. The external acoustic reflection signal received by the crystal transducer is converted into a low-voltage reflection electrical signal, which is transmitted through the transformer and then output after being divided by a small resistor, and is successfully transmitted to the high-speed signal isolation circuit. refer to Figure 3 As shown, in some embodiments, the power supply control circuit of the pulse processing circuit is controlled by the host computer to provide controllable operating power to the high-voltage switching circuit, the low-voltage power supply boost circuit, and the high-speed signal isolation circuit. Its working logic is as follows: when the host computer sends a pulse generation signal (signal set to 1), the optocoupler in this circuit turns on and pulls the gate of the internal MOS transistor Q2 low, and the MOS transistor Q2 turns on, converting 3.6VISO / SGND into 3.6V' operating power to supply power to the processing side of the high-voltage switching circuit, the low-voltage power supply boost circuit, and the high-speed signal isolation circuit; when the host computer does not send a pulse generation signal (signal set to 0), the optocoupler does not work, the gate of the MOS transistor Q2 is connected to the power supply, the MOS transistor Q2 turns off, the 3.6V' is cut off, and the high-voltage switching circuit, the low-voltage power supply boost circuit, and the high-speed signal isolation circuit stop working, realizing controllable power on and off of the circuit module.

[0035] refer to Figure 4 As shown, in some implementations, the low-voltage power supply boost circuit is a typical boost circuit. Its input terminal is connected to the 3.6V' output terminal of the pulse processing circuit power supply control circuit. Its core function is to provide an appropriate operating voltage for the switch control circuit and the high-speed signal isolation circuit. Its working process is as follows: the management chip U2 in the circuit generates a PWM switching signal. When the PWM signal output is low, the internal MOSFET Q3 is turned on, and the 3.6V' power supply charges the inductor L1. When the PWM signal output is high, the MOSFET Q3 is turned off. Since the inductor current does not change abruptly, the large current in the circuit is released through the diode, and the voltage is raised by the load impedance, ultimately generating the 5VISO / SGND internal operating power supply. This 5VISO / SGND power supply supplies power to the optocoupler output side of the switch control circuit and the insulated gate input side (processing side) of the high-speed signal isolation circuit, solving the problem that the conventional 3.3V power supply cannot meet the operating voltage requirements of the relevant circuits.

[0036] refer to Figure 5As shown, in some embodiments, the switch control circuit includes an optocoupler isolation unit, which is coordinated with the pulse generation circuit under the timing control of the host computer. Its core function is to receive the control signal from the host computer and output the control signal CTL2 to the high-voltage switch circuit, while simultaneously achieving signal isolation and control signal voltage boosting. Its working logic is as follows: the transmitting side of the circuit is powered by 3.3V / GND, and the output side of the optocoupler is powered by 5VISO / SGND generated by the low-voltage power supply boost circuit, ensuring that the gate-source voltage Vgs of the power MOSFET Q1 of the high-voltage switch circuit is greater than the gate turn-on voltage Vth; when the host computer sends a pulse generation signal (signal set to 1, PWM2 set to 1), the CTL1 signal is pulled low, the optocoupler stops working, and the CTL2 control signal output is high; when the host computer's pulse generation signal ends (signal set to 0, PWM2 set to 0), the CTL1 signal is pulled high, the optocoupler starts working, and the CTL2 control signal output is low; by switching the level of the CTL2 signal, the working state of the high-voltage switch circuit is precisely controlled.

[0037] refer to Figure 6 As shown, in some embodiments, the high-speed signal isolation circuit includes an insulating gate unit. Its core function is to receive the low-voltage reflected signal output from the high-voltage switching circuit, isolate and level-adapt it, and then output it to the downstream acquisition circuit. The working process is as follows: the input side (processing side) of the insulating gate of the circuit is powered by 5VISO / SGND generated by the low-voltage power supply boost circuit, and the output side (receiving side) is powered by 3.3V_receive / AGND, realizing complete electrical isolation between the processing side and the receiving side; the signal output by the high-voltage switching circuit is first boosted to the midpoint voltage by voltage division with the power supply, and then isolated by the insulating gate unit, finally obtaining a standard low-voltage reflected signal with the same ground as the receiving side, and outputting it to the downstream acquisition circuit, ensuring that the signal received by the acquisition circuit is pure and accurate, and avoiding electrical crosstalk and signal aliasing on the high-voltage processing side.

[0038] The modules of the high-voltage pulse reflection signal processing circuit in this embodiment work together, with the host computer as the control core, to realize the multiplexing of transmission and reception of the same crystal transducer. The complete workflow is as follows: 1. Host computer starts pulse generation command: The host computer sends a pulse generation signal, which on the one hand controls the power supply control circuit of the pulse processing circuit to turn on and generate 3.3V' to power the subsequent modules. The low voltage power supply boost circuit works simultaneously to generate 5VISO / SGND. On the other hand, it controls the CTL2 signal of the switch control circuit to be pulled low in advance, so that the MOS transistor Q1 of the high voltage switch circuit enters the cutoff region, and at the same time controls the pulse generation circuit to generate a high voltage transmission pulse. 2. High-voltage transmission pulse output and suppression: The high-voltage transmission pulse from the pulse generation circuit is transmitted to the high-voltage switching circuit, where it is suppressed to about 2V by a large resistor voltage divider. The transformer then excites the crystal transducer to generate an acoustic signal. At this time, the high-voltage signal is effectively suppressed and will not cause damage to subsequent circuits. 3. Pulse generation ends, reflected signal is received: The host computer stops the pulse generation signal, the CTL2 signal of the switch control circuit is delayed and pulled high, so that the MOS transistor Q1 of the high voltage switch circuit enters the linear region. The crystal transducer receives the external acoustic reflection signal and converts it into a low voltage reflected electrical signal. After being divided by the small resistor of the high voltage switch circuit, it is transmitted to the high-speed signal isolation circuit. 4. Signal Isolation and Acquisition: The high-speed signal isolation circuit divides and boosts the low-voltage reflected signal to the midpoint voltage. After electrical isolation is achieved by the insulating grid unit, the output standard signal, which shares the same ground with the receiving side, is sent to the acquisition circuit, which performs analog-to-digital conversion and data processing of the signal. 5. Circuit Standby: After a single signal processing operation is completed, the circuit waits for the host computer to respond. Figure 1 T1 and shown Figure 5 A new command signal is generated at PWM2 to repeat the workflow described in steps 1-4 above. If the host computer determines that the work is complete, it will control... Figure 3 T10 and shown Figure 5 The two PWM control signals shown stop being sent, the connection between 3.6V' and 3.6VISO is disconnected, the processing circuit stops being powered, all modules stop working, and the circuit enters a low-power standby state.

[0039] The embodiments of this application, through the above technical solutions, have at least the following beneficial effects: 1. The high-voltage transmit pulse output and low-voltage reflective signal reception of the same crystal transducer were multiplexed, which met the design requirements of miniaturization and high precision of the equipment and solved the core technical problem of high-voltage pulse and low-voltage reflective signal aliasing and burning out the acquisition chip when a single crystal transducer was multiplexed. 2. The power MOSFET Q1 in the high-voltage switching circuit never directly turns off or on the high voltage, which fundamentally avoids the arcing phenomenon caused by the switching transistor turning off the high voltage in traditional switching circuits, thus improving the service life and operational stability of the circuit. 3. Through a two-stage isolation design of physical power supply isolation and high-speed signal isolation, the aliasing of switching signals, pulse signals and acquisition signals is completely avoided, the risk of circuit damage caused by interference between signals from different sources is avoided, and the acquisition accuracy of reflected signals is guaranteed. 4. The power supply control circuit of the pulse processing circuit realizes the controllable power on and off of the module, which effectively reduces the overall power consumption of the circuit. At the same time, the voltage adaptation design of each module ensures the stability and reliability of the circuit operation.

[0040] The above description is only a preferred embodiment of this application and is not intended to limit this application. The circuit component parameters and specific models not described in detail in the embodiments can be adapted and selected according to the actual acoustic measurement, ranging and other application scenarios. Any modifications, equivalent substitutions and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A high-voltage pulse reflection signal processing circuit, characterized in that, It includes a pulse generation circuit, a high-voltage switching circuit, a switching control circuit, and a high-speed signal isolation circuit; The pulse generation circuit is used to generate a high-voltage transmission pulse and transmit it to the high-voltage switching circuit, which is connected to the crystal transducer. Both the switch control circuit and the pulse generation circuit are controlled by the host computer. When the pulse generation circuit generates a high-voltage transmission pulse, the switch control circuit controls the high-voltage switch circuit to suppress the high-voltage transmission pulse waveform according to the host computer control signal. After the high-voltage transmission pulse is generated, the switch control circuit controls the high-voltage switch circuit to allow the low-voltage reflected signal to pass through according to the control signal from the host computer; The high-speed signal isolation circuit is used to receive the low-voltage reflected signal output by the high-voltage switching circuit and isolate the low-voltage reflected signal to the downstream acquisition circuit.

2. The high-voltage pulse reflection signal processing circuit according to claim 1, characterized in that, It also includes a low-voltage power supply boost circuit, which is used to provide an appropriate operating voltage for the switch control circuit and the high-speed signal isolation circuit. The low-voltage power supply boost circuit is a boost circuit.

3. The high-voltage pulse reflection signal processing circuit according to claim 2, characterized in that, It also includes a pulse processing circuit power supply control circuit, which is controlled by the host computer and provides controllable operating power to the high-voltage switching circuit, the low-voltage power supply boost circuit and the high-speed signal isolation circuit. When the host computer sends a pulse generation signal, the pulse processing circuit power supply control circuit is turned on to supply power, and when the host computer does not send a pulse generation signal, the pulse processing circuit power supply control circuit is turned off to cut off power.

4. The high-voltage pulse reflection signal processing circuit according to claim 3, characterized in that, The input power supply of the high-voltage pulse reflection signal processing circuit includes four power supplies: 3.3V / GND, HV / GND, 3.6V ISO / SGND, and 3.3V_receive / AGND. There is no electrical isolation between 3.3V / GND and HV / GND, while the other power supplies are physically isolated from each other. The 3.3V / GND supply power to the transmitting side of the pulse generation circuit and the switch control circuit, and also supplies power to the host computer; the HV / GND provides high voltage for the pulse generation circuit, working in conjunction with 3.3V / GND to generate high-voltage transmission pulses; the 3.6VISO / SGND is the main power supply for the pulse processing circuit power control circuit, which, after circuit conversion, provides operating power to the processing side of the high-voltage switch circuit, the low-voltage power supply boost circuit, and the high-speed signal isolation circuit; the 3.3V_receive / AGND supplies power to the receiving side of the high-speed signal isolation circuit, providing a suitable power environment for the isolated signal output to the acquisition circuit.

5. The high-voltage pulse reflection signal processing circuit according to claim 1, characterized in that, The pulse generation circuit includes a CMOS amplifier unit and a power MOSFET Q5. The narrow pulse sent by the host computer is amplified by the CMOS amplifier unit to enhance the output capability and then controls the switching on and off of the power MOSFET Q5. When the power MOSFET Q5 is on, it outputs high voltage to the high voltage switching circuit. When the power MOSFET Q5 is off, it releases charge through a diode to achieve a rapid voltage drop, thus completing the generation of the high voltage transmission pulse.

6. The high-voltage pulse reflection signal processing circuit according to claim 1, characterized in that, The high-voltage switching circuit includes a transformer and a power MOSFET Q1. The primary side of the transformer is connected to a pulse generation circuit, and the secondary side is connected to a crystal transducer. The control signal CTL2 output by the switching control circuit controls the operating state of the power MOSFET Q1 in the high-voltage switching circuit. During the high-voltage pulse transmission phase, the power MOSFET Q1 operates in the cutoff region, and the high-voltage pulse is output after being divided by a large resistor. During the low-voltage reflected signal phase, the power MOSFET Q1 operates in the linear region, and the low-voltage reflected signal is output after being divided by a small resistor.

7. The high-voltage pulse reflection signal processing circuit according to claim 6, characterized in that, The control signal CTL2 is pulled low before the control signal of the pulse generation circuit is set to 1, and pulled high after the control signal of the pulse generation circuit is set to 0.

8. The high-voltage pulse reflection signal processing circuit according to claim 7, characterized in that, The amplitude of the high-voltage transmission pulse is reduced to 1.9-2.1V after being divided by a large resistor, and the preset threshold is 4.9-5.1V.

9. The high-voltage pulse reflection signal processing circuit according to claim 2, characterized in that, The switch control circuit includes an optocoupler isolation unit for receiving control signals from the host computer and outputting control signal CTL2 to the high-voltage switch circuit. The operating voltage of the switch control circuit is provided by the low-voltage power supply boost circuit to ensure that the gate-source voltage Vgs of the power MOSFET Q1 in the high-voltage switch circuit is greater than the gate turn-on voltage Vth.

10. The high-voltage pulse reflection signal processing circuit according to claim 1, characterized in that, The high-speed signal isolation circuit includes an insulating gate unit. The input of the insulating gate unit is powered by the processing side power supply 5VISO / SGND, and the output is powered by the receiving side power supply 3.3V_receive / AGND. After the signal output from the high-voltage switching circuit is divided and boosted to the midpoint voltage, the insulating gate unit achieves electrical isolation between the processing side and the receiving side, and outputs a signal with the same ground as the receiving side to the acquisition circuit.

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