Ultrasonic transducer signal amplification circuit and electronic chip

Abstract

This invention discloses an ultrasonic transducer signal amplification circuit and an electronic chip. The ultrasonic transducer signal amplification circuit includes: a first-stage amplification circuit, a second-stage amplification circuit, and a low-pass filter circuit disposed between the first-stage and second-stage amplification circuits. The first-stage amplification circuit is used to initially amplify the ultrasonic input signal; the low-pass filter circuit is used to filter out high-frequency interference from the output signal of the first-stage amplification circuit; and the second-stage amplification circuit is used to further amplify the interference-filtered output signal. This invention can effectively amplify ultrasonic signals and reduce crosstalk signals.

Description

Technical Field

[0001] This utility model relates to the field of integrated circuit design technology, and in particular to an ultrasonic transducer signal amplification circuit and electronic chip. Background Technology

[0002] An ultrasonic transducer is an electronic device that converts electrical energy into ultrasonic waves. It has wide applications in fields such as medical ultrasound, industrial inspection, materials analysis, and acoustic measurement.

[0003] During propagation, ultrasonic waves attenuate due to absorption, scattering, and diffraction, especially in complex media where signal strength can be significantly reduced. When ultrasonic waves encounter interfaces between different media, some signals are reflected and some penetrate, leading to a substantial decrease in the received signal strength. In practical applications, various environmental noises (such as mechanical vibrations and electromagnetic interference) can also interfere with weak signals, further reducing the signal-to-noise ratio.

[0004] In order to effectively extract and utilize the weak signals received by the ultrasonic transducer, they need to be processed to meet the needs of practical applications. Utility Model Content

[0005] This invention provides an ultrasonic transducer signal amplification circuit and electronic chip, which can solve the above-mentioned problems of interference and weak signal, and can meet the needs of practical applications.

[0006] This utility model provides an ultrasonic transducer signal amplification circuit, comprising: a first-stage amplification circuit, a second-stage amplification circuit, and a low-pass filter circuit disposed between the first-stage amplification circuit and the second-stage amplification circuit; the first-stage amplification circuit is used to initially amplify the ultrasonic input signal; the low-pass filter circuit is used to filter out high-frequency interference from the output signal of the first-stage amplification circuit; and the second-stage amplification circuit is used to amplify the output signal after interference filtering.

[0007] In one embodiment, a boost circuit is further provided at the input terminal of the first-stage amplifier circuit. The boost circuit consists of a first DC power supply, a first resistor, and a second resistor. The first resistor and the second resistor form a voltage divider circuit for the first DC power supply to provide an appropriate DC bias for the first-stage amplifier circuit.

[0008] In one embodiment, a second capacitor for isolating DC is also provided at the input terminal of the first-stage amplifier circuit, and the ultrasonic input signal is connected to the input terminal of the first-stage amplifier circuit through the second capacitor.

[0009] In one embodiment, the first-stage amplifier circuit includes a first operational amplifier, a fourth resistor, and a sixth resistor. The sixth resistor is connected across the inverting input and output of the first operational amplifier, and the fourth resistor is connected between the inverting input of the first inverting operational amplifier and ground, so that the fourth and sixth resistors can adjust the amplification factor of the first-stage amplifier circuit. A third capacitor is also connected in series between the fourth resistor and ground to isolate the DC component in the first-stage amplified signal.

[0010] In one embodiment, the second-stage amplifier circuit includes a second operational amplifier, a seventh resistor, and a tenth resistor. The tenth resistor is connected across the inverting input and output of the second operational amplifier, and the seventh resistor is connected between the inverting input of the second operational amplifier and ground, so that the seventh and tenth resistors can adjust the amplification factor of the second-stage amplifier circuit. A sixth capacitor is also connected in series between the seventh resistor and ground to isolate the DC component in the second-stage amplified signal.

[0011] In one embodiment, the low-pass filter circuit includes a fifth resistor and a fifth capacitor connected sequentially between the output terminal of the first-stage amplifier circuit and ground, and the connection point of the fifth resistor and the fifth capacitor is connected to the non-inverting input terminal of the second-stage amplifier circuit.

[0012] In one embodiment, the ultrasonic transducer signal amplification circuit further includes a ground discharge circuit, which includes a ninth resistor connected between the ultrasonic input signal and ground.

[0013] This utility model embodiment also provides an electronic chip, including the ultrasonic transducer signal amplification circuit described above.

[0014] This embodiment of the invention achieves effective amplification of ultrasonic signals by using a two-stage amplification circuit in conjunction with voltage boosting and DC blocking; furthermore, by using a ground discharge circuit, the attenuation rate of the self-oscillation energy of the ultrasonic transducer caused by crosstalk signals is accelerated, reducing the impact on ultrasonic signal acquisition. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This invention provides a schematic diagram of an ultrasonic transducer signal amplification circuit according to an embodiment of the present invention.

[0017] Figure 2The spectrum obtained for testing the circuit provided in the embodiment of this utility model. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0019] The ultrasonic signal output by the ultrasonic transducer is weak and easily interfered with, which is not conducive to transmission and extraction. Therefore, this utility model provides an ultrasonic transducer signal amplification circuit, which needs to amplify and filter the signal to enhance the signal strength, remove unnecessary high-frequency or low-frequency noise crosstalk, and improve the clarity and recognizability of the signal. That is, by performing two-stage amplification and high-frequency interference filtering on the ultrasonic signal, the desired ultrasonic signal can be obtained.

[0020] To make the technical solution of this utility model clearer, the embodiments of this utility model will be described in detail below with reference to the accompanying drawings.

[0021] Figure 1 A schematic diagram of an ultrasonic transducer signal amplification circuit provided in an embodiment of this utility model is shown below. Figure 1 As shown, the amplification circuit of this embodiment includes: a first-stage amplification circuit, a second-stage amplification circuit, and a low-pass filter circuit disposed between the first-stage amplification circuit and the second-stage amplification circuit; the first-stage amplification circuit is used to initially amplify the ultrasonic input signal; the low-pass filter circuit is used to filter out high-frequency interference from the output signal of the first-stage amplification circuit; and the second-stage amplification circuit is used to amplify the output signal after interference filtering.

[0022] In practical applications, the first-stage amplifier circuit may include: a first operational amplifier U1, a fourth resistor R4, and a sixth resistor R6. The sixth resistor R6 is connected across the inverting input and output of the first operational amplifier U1, and the fourth resistor R4 is connected between the inverting input of the first inverting operational amplifier and ground. This allows the fourth resistor R4 and the sixth resistor R6 to adjust the amplification factor of the first-stage amplifier circuit. Since the amplitude of the ultrasonic input signal VG1 is relatively small, a smaller input resistor R4 is used to ensure low signal noise. To ensure that the amplifier circuit amplifies only AC signals, a third capacitor C3 is connected in series between the fourth resistor R4 and ground to isolate the DC component in the first-stage amplified signal.

[0023] The second-stage amplifier circuit may include: a second operational amplifier U2, a seventh resistor R7, and a tenth resistor R10. The tenth resistor R10 is connected across the inverting input and output of the second operational amplifier U2. The seventh resistor R7 is connected between the inverting input of the second operational amplifier and ground, allowing the seventh and tenth resistors to adjust the amplification factor of the second-stage amplifier circuit. Since the signal has been amplified by the first stage, a larger input resistor R7 and a larger feedback resistor R10 are required to ensure that the operational amplifier output current is driven within its operating range. To ensure that the amplifier circuit only amplifies AC signals, a sixth capacitor C6 is connected in series between the seventh resistor R7 and ground to isolate the DC component in the signal amplified by the second stage.

[0024] In the above embodiments, in order to ensure the bandwidth of the amplified signal, the amplification factor of the single-stage operational amplifier circuit cannot be too high, otherwise it will attenuate the core frequency of the amplified signal.

[0025] The low-pass filter circuit includes a fifth resistor R5 and a fifth capacitor C5 connected sequentially between the output terminal of the first-stage amplifier circuit and ground. The connection point of the fifth resistor R5 and the fifth capacitor C5 is connected to the non-inverting input terminal of the second-stage amplifier circuit. By setting up the low-pass filter circuit, high-frequency interference in the circuit can be filtered out.

[0026] In the above embodiment, a boost circuit is further provided at the input terminal of the first-stage amplifier circuit. The boost circuit consists of a first DC power supply V1, a first resistor R1, and a second resistor R2. The first resistor and the second resistor form a voltage divider circuit for the first DC power supply to provide a suitable DC bias for the first-stage amplifier circuit. The voltage division between the first resistor R1 and the second resistor R2 forms a DC boost level, which can accurately bias the AC signal to a suitable DC window, allowing the ultrasonic input signal VG1 to be amplified within the optimal operating voltage window of the operational amplifier. The first capacitor C1 connected across the second resistor R2 acts as a filter.

[0027] A second capacitor C2 for isolating DC is also provided at the input terminal of the first-stage amplifier circuit. The ultrasonic input signal VG1 is connected to the input terminal of the first-stage amplifier circuit through the second capacitor C2.

[0028] To accelerate the attenuation of crosstalk signals at the input of the amplifier circuit, a ground discharge circuit is also configured in the above embodiment. The ground discharge circuit is the ninth resistor R9 connected between the ultrasonic input signal VG1 and ground, i.e., the ground pull-up resistor. By adding the ground pull-up resistor R9, a ground circuit is formed, which accelerates the attenuation of the transducer self-oscillation energy caused by crosstalk signals.

[0029] This embodiment of the invention achieves effective amplification of ultrasonic signals by using a two-stage amplification circuit in conjunction with voltage boosting and DC blocking; furthermore, by using a ground discharge circuit, the attenuation rate of the self-oscillation energy of the ultrasonic transducer caused by crosstalk signals is accelerated, reducing the impact on ultrasonic signal acquisition.

[0030] Figure 2 The spectrum obtained for testing the circuit provided in the embodiment of this utility model, such as Figure 2 As shown, the amplifier circuit in this embodiment of the present invention can generate a gain of 58.14dB for a 200kHz signal without amplifying the DC signal; compared with the first-order amplifier circuit, the second-order circuit in this embodiment has a bandwidth that is basically the same, while increasing the amplification factor.

[0031] Based on the amplification circuit in the above embodiments, this utility model also provides an electronic chip, which includes the ultrasonic transducer signal amplification circuit described above. This electronic chip can be used in ultrasonic transducer circuits, effectively amplifying ultrasonic signals and reducing the impact of crosstalk between ultrasonic transceiver circuits on signal acquisition.

[0032] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. A signal amplification circuit for an ultrasonic transducer, characterized in that, include: The circuit consists of a first-stage amplifier circuit, a second-stage amplifier circuit, and a low-pass filter circuit located between the first-stage amplifier circuit and the second-stage amplifier circuit. The first-stage amplifier circuit is used to initially amplify the ultrasonic input signal; The low-pass filter circuit is used to filter out high-frequency interference from the output signal of the first-stage amplifier circuit. The second-stage amplifier circuit is used to amplify the output signal after interference filtering.

2. The ultrasonic transducer signal amplification circuit according to claim 1, characterized in that, A boost circuit is also provided at the input terminal of the first-stage amplifier circuit. The boost circuit consists of a first DC power supply, a first resistor, and a second resistor. The first resistor and the second resistor form a voltage divider circuit for the first DC power supply to provide an appropriate DC bias for the first-stage amplifier circuit.

3. The ultrasonic transducer signal amplification circuit according to claim 1, characterized in that, A second capacitor for isolating DC is also provided at the input terminal of the first-stage amplifier circuit. The ultrasonic input signal is connected to the input terminal of the first-stage amplifier circuit through the second capacitor.

4. The ultrasonic transducer signal amplification circuit according to claim 1, characterized in that, The first stage amplifier circuit includes a first operational amplifier, a fourth resistor, and a sixth resistor. The sixth resistor is connected across the inverting input terminal and the output terminal of the first operational amplifier, and the fourth resistor is connected between the inverting input terminal of the first inverting operational amplifier and ground, so that the fourth resistor and the sixth resistor can adjust the amplification factor of the first stage amplifier circuit.

5. The ultrasonic transducer signal amplification circuit according to claim 4, characterized in that, A third capacitor is also connected in series between the fourth resistor and ground to isolate the DC component in the first-stage amplified signal.

6. The ultrasonic transducer signal amplification circuit according to claim 1, characterized in that, The second-stage amplifier circuit includes a second operational amplifier, a seventh resistor, and a tenth resistor. The tenth resistor is connected across the inverting input and output of the second operational amplifier, and the seventh resistor is connected between the inverting input of the second inverting operational amplifier and ground, so that the seventh resistor and the tenth resistor can adjust the amplification factor of the second-stage amplifier circuit.

7. The ultrasonic transducer signal amplification circuit according to claim 6, characterized in that, A sixth capacitor is also connected in series between the seventh resistor and ground to isolate the DC component in the second-stage amplified signal.

8. The ultrasonic transducer signal amplification circuit according to claim 1, characterized in that, The low-pass filter circuit includes a fifth resistor and a fifth capacitor connected sequentially between the output terminal of the first-stage amplifier circuit and ground. The connection point of the fifth resistor and the fifth capacitor is connected to the non-inverting input terminal of the second-stage amplifier circuit.

9. The ultrasonic transducer signal amplification circuit according to any one of claims 1-8, characterized in that, It also includes a ground discharge circuit, which includes a ninth resistor connected between the ultrasonic input signal and ground.

10. An electronic chip, characterized in that, Includes the ultrasonic transducer signal amplification circuit as described in any one of claims 1 to 9.

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