Ultrasonic detection circuit and vehicle
By using an impedance matching network, a programmable gain adjustment circuit, and a voltage conversion module, the impedance mismatch and power supply incompatibility issues between the ultrasonic probe and the driver chip were resolved, enabling the ultrasonic detection circuit to be widely applicable and operate stably, thereby improving detection results and safety.
Patent Information
- Application Number
- CN202511078710.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-01
- Publication Date
- 2025-11-14
AI Technical Summary
In the prior art, impedance mismatch between the ultrasonic probe and the probe driver chip leads to severe attenuation of the echo signal, and incompatibility of the power supply voltage limits the applicability and detection effect of the ultrasonic detection circuit.
Impedance transformation and transmission loss compensation between the probe and the driver chip are achieved through an impedance matching network and a programmable gain adjustment circuit. Power conversion is performed through a voltage conversion module, and the probe status is monitored by a probe status detection circuit to ensure stable circuit operation.
The pin compatibility and applicability of the probe driver chip have been improved, ensuring the effectiveness of ultrasonic testing and enhancing testing stability and safety.
Smart Images
Figure CN120949247A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of ultrasonic testing technology, and more particularly to an ultrasonic testing circuit and a vehicle. Background Technology
[0002] The use of ultrasonic probes in automobiles is becoming increasingly widespread. For example, ultrasonic probes placed at the rear and front of the vehicle are used to detect the surrounding environment, identify objects, and eliminate blind spots. However, this technology requires the selection of ultrasonic probe driver chips and ultrasonic probes with matching parameters to construct the ultrasonic detection circuit, which presents significant application limitations. Summary of the Invention
[0003] This application aims to at least partially address one of the technical problems in the related art. Therefore, the first objective of this application is to propose an ultrasonic detection circuit that achieves impedance matching by using an impedance matching network to transform the impedance of the ultrasonic probe and the probe driver chip, and compensates for transmission loss through a programmable gain adjustment circuit, thereby ensuring the ultrasonic detection effect and improving the pin compatibility and applicability of the probe driver chip.
[0004] The second objective of this application is to propose a vehicle.
[0005] To achieve the above objectives, a first aspect of this application provides an ultrasonic detection circuit, comprising: a probe driver chip and an ultrasonic probe; an impedance matching network, the input of which is connected to the drive output pin of the probe driver chip, and the output of which is connected to the trigger pin of the ultrasonic probe, for impedance matching between the probe driver chip and the ultrasonic probe; and a programmable gain adjustment circuit, the input of which is connected to the echo output pin of the ultrasonic probe, and the output of which is connected to the echo input pin of the probe driver chip, for compensating for transmission loss of the echo signal detected by the ultrasonic probe.
[0006] According to the ultrasonic detection circuit of this application embodiment, the drive output pin of the probe driver chip is connected to the trigger pin of the ultrasonic probe through an impedance matching network. The impedance matching network matches the impedance between the probe driver chip and the ultrasonic probe. The echo output pin of the ultrasonic probe is connected to the echo input pin of the probe driver chip through a programmable gain adjustment circuit. The programmable gain adjustment circuit compensates for transmission loss in the echo signal detected by the ultrasonic probe. Thus, this circuit achieves impedance matching between the ultrasonic probe and the probe driver chip through the impedance matching network, and compensates for transmission loss through the programmable gain adjustment circuit, ensuring the ultrasonic detection effect and improving the pin compatibility and applicability of the probe driver chip.
[0007] In addition, the ultrasonic detection circuit according to the above embodiments of this application may also have the following additional technical features:
[0008] According to one embodiment of this application, the impedance matching network is configured based on the equivalent impedance of the ultrasonic probe.
[0009] According to one embodiment of this application, the ultrasonic detection circuit further includes a voltage conversion module, one end of which is connected to the power supply pin of the ultrasonic probe, and the other end of which is connected to the power supply pin of the probe driver chip.
[0010] According to one embodiment of this application, the voltage conversion module is a step-down module, which is used to step down the power supply voltage of the power supply pin of the ultrasonic probe to supply power to the power supply pin of the probe driver chip.
[0011] According to one embodiment of this application, the probe driver chip includes a logic circuit, and the power supply pin of the probe driver chip is connected to the power supply terminal of the logic circuit.
[0012] According to one embodiment of this application, the ultrasonic detection circuit further includes: a probe status detection circuit, the input terminal of which is connected to the ground terminal of the ultrasonic probe, and the first output terminal of which is connected to the fault flag terminal of the probe driver chip, for determining the current status of the ultrasonic probe based on the operating current of the ultrasonic probe, so as to generate a corresponding status evaluation signal.
[0013] According to one embodiment of this application, the probe status detection circuit generates a first level signal when the operating current of the ultrasonic probe is within a preset allowable range, and generates a second level signal when the operating current of the ultrasonic probe is outside the preset allowable range.
[0014] According to one embodiment of this application, the second output terminal of the probe status detection circuit is connected to the fault indication pin of the probe driver chip, and is also used to detect open circuit faults in the ultrasonic probe based on the operating current of the ultrasonic probe, and generate a fault interrupt signal when it is determined that there is an open circuit fault in the ultrasonic probe, so as to trigger the fault indication pin of the probe driver chip to be interrupted.
[0015] According to one embodiment of this application, the probe status detection circuit determines that the ultrasonic probe has an open circuit fault when the operating current of the ultrasonic probe is less than a preset current threshold.
[0016] To achieve the above objectives, a second aspect of this application provides a vehicle including the ultrasonic detection circuit described above.
[0017] The vehicle according to the embodiments of this application, based on the ultrasonic detection circuit described above, ensures the ultrasonic detection results and provides a guarantee for the stable operation of the vehicle.
[0018] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description
[0019] Figure 1 This is a schematic diagram of the connection of the ultrasonic detection circuit according to an embodiment of this application;
[0020] Figure 2 This is a schematic diagram of the connection of an ultrasonic detection circuit according to an embodiment of this application;
[0021] Figure 3 This is a block diagram of a vehicle according to an embodiment of this application. Detailed Implementation
[0022] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.
[0023] The ultrasonic detection circuit and vehicle proposed in this application are described below with reference to the accompanying drawings.
[0024] Figure 1 This is a schematic diagram of the connection of the control circuit of the ultrasonic probe 20 according to an embodiment of this application.
[0025] like Figure 1 As shown, the ultrasonic probe 20 control circuit of this application embodiment includes: a probe driver chip 10, an ultrasonic probe 20, an impedance matching network 30, and a programmable gain adjustment circuit 40.
[0026] The impedance matching network 30 has its input terminal connected to the drive output pin TX of the probe driver chip 10 and its output terminal connected to the trigger pin TRIG of the ultrasonic probe 20. The impedance matching network 30 is used to perform impedance matching between the probe driver chip 10 and the ultrasonic probe 20. The programmable gain adjustment circuit 40 has its input terminal connected to the echo output pin ECHO of the ultrasonic probe 20 and its output terminal connected to the echo input pin RX of the probe driver chip 10. The programmable gain adjustment circuit 40 is used to compensate for transmission loss of the echo signal detected by the ultrasonic probe 20.
[0027] Specifically, taking the ultrasonic probe 20 as a TB185 ultrasonic probe and the probe driver chip 10 as an Elmos driver chip as an example, the TB185 ultrasonic probe is an ultrasonic sensor system (USS). The Elmos driver chip (such as E524.14 / E524.24, etc.) integrates an 8-bit MCU (microcontroller unit), which can directly drive a transformer with a center tap, thereby driving the ultrasonic probe. The programmable frequency range is 30kHz to 80kHz, and it supports measurement distances from 15cm to 4m (normal mode) or even further (extended mode). The received echo signal is amplified, filtered, and converted by an ADC (Analog-to-Digital Converter) before being sent to the MCU.
[0028] However, the TB185 probe (typical parameters: 58kHz frequency, ±10% tolerance) has an impedance mismatch with the default configuration of the Elmos chip (probe impedance ≈ 800Ω, Elmos drive output impedance ≈ 50Ω), resulting in an echo signal attenuation of >30%.
[0029] To improve the ultrasonic detection effect, this embodiment sets an impedance matching network 30, such as an LC (Inductance Capacitance) network (L = 22μH, C = 1nF), between the drive output pin TX of the probe driver chip 10 and the trigger pin TRIG of the ultrasonic probe 20 to realize impedance transformation between the ultrasonic probe 20 and the probe driver chip 10 (800Ω~50Ω). A programmable gain adjustment circuit 40, such as a PGA (Programmable Gain Amplifier) circuit (adjustable gain range 20dB-60dB), is set between the echo output pin ECHO of the ultrasonic probe 20 and the echo input pin RX of the probe driver chip 10 to compensate for transmission loss.
[0030] Therefore, this embodiment improves the pin compatibility and applicability of the probe driver chip through impedance matching network and programmable gain adjustment circuit, thus ensuring the ultrasonic detection effect.
[0031] In some embodiments of this application, the impedance matching network 30 is configured according to the equivalent impedance of the ultrasonic probe 20.
[0032] Specifically, continuing with the example of the TB185 ultrasonic probe 20, in the implementation of the impedance matching network 30, the equivalent impedance of the TB185 probe is first calculated. The equivalent impedance can be tested according to the actual situation; assuming the measured value is 800Ω@58kHz, the impedance of the impedance matching network 30 at the resonant point is adjusted to 800Ω to match the target impedance of the TB185 probe, thereby ensuring impedance matching effect and achieving better detection distance, resolution, and lower power consumption.
[0033] Furthermore, taking impedance matching network 30 as an LC network as an example, the LC matching network is as follows:
[0034]
[0035] This means that the impedance of the LC network (L = 22μH, C = 1nF) needs to be matched to 800Ω. The specific steps are as follows:
[0036] First, calculate the equivalent impedance of the original LC network using the following formula:
[0037]
[0038] Therefore, in this embodiment, the LC network is calculated to exhibit a purely resistive high impedance (4690Ω) at the resonant frequency (1.075MHz).
[0039] Then, calculate the parallel resistance to reduce the 4690Ω to 800Ω using the parallel resistance. The calculation formula is as follows:
[0040]
[0041] The parallel resistance Rp was calculated to be 965Ω. This parallel resistance lowers the original high impedance of the LC network to 800Ω. At this point, the equivalent impedance of the LC network at the resonant point is approximately 800Ω, matching the target impedance of the TB185 probe. The parallel resistance must be a high-frequency non-inductive resistor (such as a metal film or thick-film resistor) to avoid the influence of parasitic inductance. Furthermore, its actual temperature stability (resistance temperature drift < ±50ppm / ℃) must be verified.
[0042] This embodiment simply reduces the impedance from 4690Ω to 800Ω by connecting a parallel resistor across the LC network. It is simple, effective, controls application costs, and can meet the matching requirements of different ultrasonic probes 20.
[0043] Combination Figure 2 As shown, in some embodiments of this application, the ultrasonic detection circuit further includes a voltage conversion module 50, one end of which is connected to the power supply pin VCC of the ultrasonic probe 20, and the other end of which is connected to the power supply pin VDD of the probe driver chip 10.
[0044] Specifically, continuing with the example of an ultrasonic probe 20 being a TB185 ultrasonic probe and a probe driver chip 10 being an Elmos driver chip, the power supply voltage of the TB185's VCC pin is 12V, while the power supply voltage of the Elmos chip's VDD pin is 3.3V. Direct connection would damage the chip. Therefore, this embodiment proposes a voltage conversion module 50 to perform voltage conversion and output between the power supply pin VCC of the ultrasonic probe 20 and the power supply pin VDD of the probe driver chip 10. For example, the voltage conversion module 50 can step down the power supply voltage at the VCC pin of the ultrasonic probe 20 to meet the power supply requirements of the VDD pin of the probe driver chip 10, thus supplying power to the VDD pin of the probe driver chip 10; alternatively, the voltage conversion module 50 can step up the power supply voltage at the VDD pin of the probe driver chip 10 to meet the power supply requirements of the VCC pin of the ultrasonic probe 20, thus supplying power to the VCC pin of the ultrasonic probe 20.
[0045] Therefore, this embodiment can realize power conversion through voltage conversion module 50 to meet different power supply application scenarios, and improve the power supply flexibility of ultrasonic probe 20 and probe driver chip 10.
[0046] In some embodiments of this application, the voltage conversion module 50 is a step-down module used to step down the power supply voltage of the power supply pin VCC of the ultrasonic probe 20 to supply power to the power supply pin VDD of the probe driver chip 10.
[0047] In other words, this embodiment uses a voltage conversion module 50 to convert the power supply voltage of the ultrasonic probe 20's power supply pin VCC to power the probe driver chip 10's power supply pin VDD. Continuing with the example of the ultrasonic probe 20 being a TB185 ultrasonic probe and the probe driver chip 10 being an Elmos driver chip, the power supply voltage of the TB185's power supply pin VCC is 12V, and the power supply voltage of the Elmos chip's power supply pin VDD is 3.3V. In application, the voltage conversion module 50 steps down the 12V power supply voltage of the TB185's power supply pin VCC to 3.3V to power the Elmos chip's power supply pin VDD, thus achieving a direct connection between the two power supply pins and improving pin compatibility.
[0048] In some embodiments of this application, the probe driver chip 10 includes logic circuitry, and the power supply pin VDD of the probe driver chip 10 is connected to the power supply terminal of the logic circuitry.
[0049] In other words, the power supply pin VDD of the probe driver chip 10 is the power supply terminal of the chip logic circuit. The 12V probe power supply is stepped down to 3.3V through the voltage conversion module 50 to supply power to the Elmos chip logic circuit, thereby improving efficiency while ensuring power supply safety.
[0050] In some embodiments of this application, the ultrasonic detection circuit further includes: a probe state detection circuit 60, the input terminal of which is connected to the ground terminal of the ultrasonic probe 20, and the first output terminal of which is connected to the fault flag pin DIAG of the probe driver chip 10, for determining the current state of the ultrasonic probe 20 based on the operating current of the ultrasonic probe 20, so as to generate a corresponding state evaluation signal.
[0051] In other words, the probe status detection circuit 60 monitors the operating current of the ultrasonic probe 20 to assess its current state based on the actual monitoring results. For example, it determines whether the ultrasonic probe 20 is in a normal state based on the amplitude and range of the operating current change. A corresponding status assessment signal is generated based on the current state of the ultrasonic probe 20 and fed back to the fault flag pin DIAG of the probe driver chip 10. For example, a first status signal is generated when the ultrasonic probe 20 is in a normal state, and a second status signal is generated when the ultrasonic probe 20 is in an abnormal state. This compensates for the limitation of the built-in diagnostics of the probe driver chip 10 in detecting probe open / short circuit faults (such as intermittent open circuits caused by corrosion of the TB185 wiring harness), thus improving the stability of ultrasonic detection.
[0052] Furthermore, the probe status detection circuit 60 is connected in parallel to the GND circuit of the ultrasonic probe. It monitors the operating current of the ultrasonic probe 20 via current mirroring, enabling the detection of whether the ultrasonic probe 20 is connected, short-circuited, open-circuited, or experiencing performance degradation without interfering with the main signal path. For example, by mirroring the probe drive current (or bias current), the probe status can be indirectly reflected using a low-voltage, small current.
[0053] In some embodiments of this application, the probe state detection circuit 60 generates a first level signal when the operating current of the ultrasonic probe 20 is within a preset allowable range, and generates a second level signal when the operating current of the ultrasonic probe 20 is outside the preset allowable range.
[0054] Specifically, the preset allowable range can be preset according to the actual situation. For example, the preset allowable range is 8mA±2mA. When the working current of the ultrasonic probe 20 is within the range of 8mA±2mA, the probe status detection circuit 60 outputs a high level, i.e., the first level signal; when the working current of the ultrasonic probe 20 is outside the range of 8mA±2mA, it outputs a low level, i.e., the second level signal.
[0055] This embodiment evaluates the working status of the ultrasonic probe 20 based on a preset allowable range, thereby improving detection efficiency and reducing detection costs.
[0056] In some embodiments of this application, the second output terminal of the probe state detection circuit 60 is connected to the fault indication pin FAULT of the probe driver chip 10, and is also used to detect open circuit faults in the ultrasonic probe 20 based on the operating current of the ultrasonic probe 20, and generate a fault interrupt signal when it is determined that there is an open circuit fault in the ultrasonic probe 20, so as to trigger the interruption of the fault indication pin FAULT of the probe driver chip 10.
[0057] In other words, the probe status detection circuit 60 also performs open-circuit fault detection on the ultrasonic probe 20 based on its operating current. Under normal conditions: probe impedance ≈ 800Ω, drive pulse current ≈ 20-50mA (depending on the drive voltage). In an open-circuit state: probe not connected / cable disconnected → current path interrupted → current ≈ 0mA (or only leakage current remains). Therefore, an open circuit is determined when the operating current is below the threshold for N consecutive pulses. Then, upon determining an open circuit, a fault interrupt signal is generated to trigger the FAULT interrupt pin of the probe driver chip 10, providing an interrupt reminder and ensuring circuit operational safety and ultrasonic detection performance.
[0058] In some embodiments of this application, the probe status detection circuit 60 determines that the ultrasonic probe 20 has an open circuit fault when the operating current of the ultrasonic probe 20 is less than a preset current threshold.
[0059] Specifically, the preset current threshold is used as the evaluation standard for open circuit faults and can be set according to the actual situation. For example, if the preset current threshold is 0.5mA, a short circuit fault is determined when the operating current is <0.5mA, triggering the FAULT pin interrupt of the probe driver chip, thereby improving fault response efficiency and circuit operation stability.
[0060] In summary, according to the ultrasonic detection circuit of this application embodiment, the drive output pin of the probe driver chip is connected to the trigger pin of the ultrasonic probe through an impedance matching network. The impedance matching network matches the impedance between the probe driver chip and the ultrasonic probe. The echo output pin of the ultrasonic probe is connected to the echo input pin of the probe driver chip through a programmable gain adjustment circuit. The programmable gain adjustment circuit compensates for transmission loss in the echo signal detected by the ultrasonic probe. Therefore, this circuit achieves impedance matching between the ultrasonic probe and the probe driver chip through the impedance matching network, and compensates for transmission loss through the programmable gain adjustment circuit, ensuring the ultrasonic detection effect and improving the pin compatibility and applicability of the probe driver chip.
[0061] Corresponding to the above embodiments, this application also proposes a vehicle.
[0062] like Figure 3 As shown, the vehicle 200 of this application embodiment includes the ultrasonic detection circuit 100 described above.
[0063] The vehicle according to the embodiments of this application, based on the ultrasonic detection circuit described above, ensures the ultrasonic detection results and provides a guarantee for the stable operation of the vehicle.
[0064] It should be understood that various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.
[0065] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.
[0066] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.
[0067] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.
[0068] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.
Claims
1. An ultrasonic detection circuit, characterized in that, include: Probe driver chip and ultrasonic probe; An impedance matching network is provided, wherein the input end of the impedance matching network is connected to the drive output pin of the probe driver chip, and the output end of the impedance matching network is connected to the trigger pin of the ultrasonic probe, for impedance matching between the probe driver chip and the ultrasonic probe. A programmable gain adjustment circuit is provided, wherein the input terminal of the programmable gain adjustment circuit is connected to the echo output pin of the ultrasonic probe, and the output terminal of the programmable gain adjustment circuit is connected to the echo input pin of the probe driver chip, for compensating for transmission loss of the echo signal detected by the ultrasonic probe.
2. The ultrasonic detection circuit according to claim 1, characterized in that, The impedance matching network is configured based on the equivalent impedance of the ultrasonic probe.
3. The ultrasonic detection circuit according to claim 1, characterized in that, Also includes: A voltage conversion module, one end of which is connected to the power supply pin of the ultrasonic probe, and the other end of which is connected to the power supply pin of the probe driver chip.
4. The ultrasonic detection circuit according to claim 3, characterized in that, The voltage conversion module is a step-down module, used to step down the power supply voltage of the power supply pin of the ultrasonic probe to supply power to the power supply pin of the probe driver chip.
5. The ultrasonic detection circuit according to claim 4, characterized in that, The probe driver chip includes logic circuitry, and the power supply pins of the probe driver chip are connected to the power supply terminals of the logic circuitry.
6. The ultrasonic detection circuit according to claim 1, characterized in that, Also includes: The probe status detection circuit has its input terminal connected to the ground terminal of the ultrasonic probe and its first output terminal connected to the fault flag terminal of the probe driver chip. It is used to determine the current status of the ultrasonic probe based on the operating current of the ultrasonic probe in order to generate a corresponding status evaluation signal.
7. The ultrasonic detection circuit according to claim 6, characterized in that, The probe status detection circuit generates a first level signal when the operating current of the ultrasonic probe is within a preset allowable range, and generates a second level signal when the operating current of the ultrasonic probe is outside the preset allowable range.
8. The ultrasonic detection circuit according to claim 6, characterized in that, The second output terminal of the probe status detection circuit is connected to the fault indication pin of the probe driver chip. It is also used to detect open circuit faults in the ultrasonic probe based on the operating current of the ultrasonic probe, and generate a fault interrupt signal when it is determined that there is an open circuit fault in the ultrasonic probe, so as to trigger the fault indication pin of the probe driver chip to be interrupted.
9. The ultrasonic detection circuit according to claim 8, characterized in that, The probe status detection circuit determines that the ultrasonic probe has an open circuit fault when the operating current of the ultrasonic probe is less than a preset current threshold.
10. A vehicle, characterized in that, Includes the ultrasonic detection circuit according to any one of claims 1-9.