Ultrasonic transmitting circuit, chip and ultrasonic module

Abstract

The present specification relates to the technical field of semiconductor technology, and particularly relates to an ultrasonic wave transmitting circuit, a chip and an ultrasonic wave module. The ultrasonic wave transmitting circuit comprises a first control circuit and a signal generating circuit. The first control circuit is configured to output a first control signal; the signal generating circuit is configured to output a driving signal according to the first control signal; the driving signal is configured to drive a first boost circuit to output an excitation signal, a voltage of the excitation signal being higher than that of the driving signal; and the excitation signal is configured to excite an ultrasonic wave transducer to emit ultrasonic waves. The embodiments of the present specification can improve the energy of the ultrasonic waves emitted by the ultrasonic wave transducer, so that the ultrasonic wave receiving circuit can receive a higher-energy echo, thereby improving the sensitivity and signal-to-noise ratio of ultrasonic wave detection.

Description

Technical Field

[0001] This specification relates to the field of semiconductor technology, and in particular to an ultrasonic transmitting circuit, chip, and ultrasonic module. Background Technology

[0002] An ultrasonic transmitting circuit drives an ultrasonic transducer to emit ultrasonic waves. The ultrasonic waves are reflected upon encountering the object being detected (e.g., a fingerprint). An ultrasonic receiving circuit (also called an ultrasonic recovery circuit) receives the reflected echo. Ultrasonic wave emission requires voltage excitation. However, in related technologies, the output voltage of the ultrasonic transmitting circuit is relatively low. Under lower voltage excitation, the energy of the ultrasonic waves emitted by the transducer is lower. Consequently, the energy of the echo received by the ultrasonic receiving circuit is lower. The signal amplitude detected by the ultrasonic receiving circuit is smaller, resulting in lower sensitivity and signal-to-noise ratio in ultrasonic detection. Summary of the Invention

[0003] This specification provides an ultrasonic transmitting circuit, chip, and ultrasonic module to increase the energy of the ultrasonic waves emitted by the ultrasonic transducer, enabling the ultrasonic receiving circuit to receive higher energy echoes, thereby improving the sensitivity and signal-to-noise ratio of ultrasonic detection.

[0004] This specification provides an ultrasonic transmitting circuit, including a first control circuit and a signal generation circuit;

[0005] The first control circuit is used to output a first control signal;

[0006] The signal generation circuit is used to output a drive signal according to the first control signal; the drive signal is used to drive the first boost circuit to output an excitation signal, the voltage of the excitation signal being higher than that of the drive signal;

[0007] The excitation signal is used to excite the ultrasonic transducer to emit ultrasonic waves.

[0008] This specification provides a driver chip, including a signal generation circuit; the signal generation circuit is used to output a drive signal according to a first control signal output by a first control circuit; the drive signal is used to drive a first boost circuit to output an excitation signal, the voltage of the excitation signal being higher than that of the drive signal, for exciting an ultrasonic transducer to emit ultrasonic waves.

[0009] This specification provides an ultrasonic module, including an ultrasonic transmitting chip, a driving chip, and a first boost circuit; the ultrasonic transmitting chip includes a first control circuit and an ultrasonic transducer, the first control circuit is used to output a first control signal, and the ultrasonic transducer is used to emit ultrasonic waves.

[0010] This specification provides an ultrasonic transmitting chip, including an ultrasonic transmitting circuit and an ultrasonic transducer.

[0011] This specification provides an ultrasonic module, including an ultrasonic transmitting chip and a first boost circuit.

[0012] This specification provides an ultrasonic transmitting circuit, including a non-overlapping circuit, a driving circuit, and a full-bridge circuit connected in sequence; the full-bridge circuit is connected to a resonant circuit, and the resonant circuit is connected to an ultrasonic transducer;

[0013] The non-overlapping circuit is used to output a non-overlapping signal to the driving circuit. The driving circuit is used to output a first control signal to the full-bridge circuit based on the non-overlapping signal. The full-bridge circuit is used to output a driving signal to the resonant circuit based on the first control signal. The resonant circuit is used to output an excitation signal to the ultrasonic transducer based on the driving signal. The voltage of the excitation signal is higher than that of the driving signal. The ultrasonic transducer is used to emit ultrasonic waves based on the excitation signal.

[0014] The non-overlapping circuit, the driving circuit, the full-bridge circuit, and the ultrasonic transducer are located on the ultrasonic transmitting chip, and the resonant circuit is an off-chip circuit of the ultrasonic transmitting chip.

[0015] Alternatively, the non-overlapping circuit, the driving circuit, and the ultrasonic transducer are located on the ultrasonic transmitting chip, the full-bridge circuit is located on the driving chip, and the resonant circuit is an off-chip circuit for the ultrasonic transmitting chip and the driving chip.

[0016] The technical solution of this specification embodiment includes an ultrasonic transmitting circuit comprising a first control circuit and a signal generation circuit. The first control circuit outputs a first control signal. The signal generation circuit outputs a drive signal based on the first control signal. The drive signal drives a first boost circuit to output an excitation signal, the voltage of which is higher than that of the drive signal. The excitation signal excites the ultrasonic transducer to emit ultrasonic waves. Therefore, through the first boost circuit, a higher voltage can be used to drive the ultrasonic transducer to emit ultrasonic waves, increasing the energy of the emitted ultrasonic waves and allowing the ultrasonic receiving circuit to receive higher-energy echoes. This improves the sensitivity and signal-to-noise ratio of ultrasonic detection. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments or prior art of this specification, the drawings used in the description of the embodiments or prior art will be briefly introduced below. The drawings described below are only some embodiments recorded in this specification. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a functional structural diagram of the ultrasonic transmitting circuit in the embodiments of this specification;

[0019] Figure 2 This is a functional structure diagram of the non-overlapping circuit in the embodiments of this specification;

[0020] Figure 3 This is a functional structure diagram of the driving circuit in the embodiments of this specification;

[0021] Figure 4 This is a functional structure diagram of the equivalent circuit of the first boost circuit and transducer in the embodiments of this specification;

[0022] Figure 5 This is a functional structural diagram of the ultrasonic transmitting circuit in the embodiments of this specification;

[0023] Figure 6 This is a functional structure diagram of the second boost circuit in the embodiments of this specification;

[0024] Figure 7 This is a functional structure diagram of the second boost circuit in the embodiments of this specification;

[0025] Figure 8 This is a functional structure diagram of the second boost circuit in the embodiments of this specification;

[0026] Figure 9 This is a functional structural diagram of the ultrasonic transmitting circuit in the embodiments of this specification;

[0027] Figure 10 This is a functional structure diagram of the step-down circuit in the embodiments of this specification;

[0028] Figure 11 This is a functional structural diagram of the ultrasonic transmitting circuit in the embodiments of this specification;

[0029] Figure 12 This is a functional structure diagram of the ultrasonic transmitting chip and the driving chip in the embodiments of this specification;

[0030] Figure 13 This is a functional structure diagram of the ultrasonic transmitting chip in the embodiments of this specification.

[0031] The following are the reference numerals used in the embodiments of this specification:

[0032] 100. Ultrasonic transmitting circuit; 200. First boost circuit; 300. Transducer; 400. Ultrasonic receiving circuit;

[0033] 101. First control circuit; 1011. First timing circuit; 1012. First drive circuit; 102. Signal generation circuit; 103. Second boost circuit; 104. Second control circuit; 105. Buck circuit; 106. Third control circuit;

[0034] 10111, Inverter; 10112, Buffer; 10113, NOR gate; 10114, NOR gate; 10115, Delay circuit; 10117, Buffer; 10118, Buffer; 10121, Switch; 10122, Switch;

[0035] 201. Inductor; 202. Capacitor; 203. Inductor; 204. Resistor; 301. Capacitor. Detailed Implementation

[0036] The technical solutions in the embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this specification, and not all embodiments. The specific embodiments described herein are only used to explain this disclosure, and not to limit this disclosure. All other embodiments obtained by those skilled in the art based on the described embodiments of this disclosure are within the scope of protection of this disclosure. In addition, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0037] This specification provides an example of an ultrasonic transmitting circuit.

[0038] Figure 1 These are schematic diagrams of the ultrasonic transmitting circuits in some embodiments of this specification. For example... Figure 1As shown, the ultrasonic transmitting circuit 100 is electrically connected to the first boost circuit 200. The first boost circuit 200 is electrically connected to the transducer 300. The ultrasonic transmitting circuit 100 can output a drive signal to drive the first boost circuit 200. The first boost circuit 200 can boost the drive signal and output an excitation signal. The transducer 300 can emit ultrasonic waves under the action of the excitation signal. Thus, the ultrasonic transmitting circuit 100 can drive the transducer 300 to emit ultrasonic waves through the first boost circuit 200. By using a higher voltage to drive the transducer 300 to emit ultrasonic waves, the energy of the ultrasonic waves emitted by the transducer 300 can be increased, allowing the ultrasonic receiving circuit 400 to receive echoes with higher energy. This improves the sensitivity and signal-to-noise ratio of ultrasonic detection.

[0039] In some embodiments, the waveform of the drive signal output by the ultrasonic transmitting circuit 100 can be, for example, a square wave, a triangle wave, a sine wave, etc. As an example, the ultrasonic transmitting circuit 100 can output one drive signal. The first boost circuit 200 can output an excitation signal based on this drive signal to excite the transducer 300 to emit ultrasonic waves. As another example, the ultrasonic transmitting circuit 100 can output multiple drive signals. The first boost circuit 200 can output an excitation signal based on multiple drive signals. The multiple drive signals can include, for example, two, three, four, etc. The waveforms, amplitudes, frequencies, etc., of the multiple drive signals are the same, but their phases can be different. For example, there can be a phase difference between the multiple drive signals, such as 180 degrees.

[0040] In some embodiments, the ultrasonic transmitting circuit 100 may include a first control circuit 101 and a signal generation circuit 102. The first control circuit 101 is electrically connected to the signal generation circuit 102. The signal generation circuit 102 is electrically connected to the first boost circuit 200. The first control circuit 101 is used to output a first control signal. The waveform of the first control signal can be a square wave, a triangle wave, a sine wave, etc. The first control signal can be a periodic timing control signal used to control the operating timing of the signal generation circuit 102. For example, the first control signal is used to control the operating state of the components in the signal generation circuit 102 (e.g., controlling the on and off states of a switch). The signal generation circuit 102 can output one or more drive signals according to the first control signal.

[0041] In some embodiments, the first control circuit 101 may include a first timing circuit 1011 and a first driving circuit 1012. The first timing circuit 1011 is electrically connected to the first driving circuit 1012. The first driving circuit 1012 is electrically connected to the signal generation circuit 102. The first timing circuit 1011 can output a first timing signal. The waveform of the first timing signal can be a square wave, a triangle wave, a sine wave, etc. The first driving circuit 1012 can amplify the first timing signal to improve the load driving capability.

[0042] As an example, the first timing circuit 1011 can output a first timing signal. The first control circuit 101 may include a first driving circuit 1012. The first driving circuit 1012 can amplify the first timing signal to obtain a first control signal. The first control signal can drive the signal generation circuit 102.

[0043] As another example, the first timing circuit 1011 can output multiple first timing signals. The first control circuit 101 may include multiple first driving circuits 1012. Each first driving circuit 1012 amplifies a first timing signal to obtain a first control signal. Multiple first control signals can jointly drive the signal generation circuit 102. The number of multiple first control signals can be 2, 3, or 4, etc. The waveforms, amplitudes, frequencies, etc., of the multiple first control signals are the same, but their phases are different. The multiple first control signals do not overlap, thus complementing each other and having a delay time (also known as non-overlap time). For example, the voltage amplitude of each first control signal can switch between positive and negative values. The moments when the voltage amplitude of multiple first control signals is 0 can be separated by non-overlap time intervals. The non-overlap time can provide a safe buffer period for the switching of the operating states of the components in the signal generation circuit 102 (such as the switching between the on and off states of a switch), ensuring that the switching is thorough and risk-free. This can improve the safety of the signal generation circuit 102.

[0044] In some embodiments, the first timing circuit 1011 can be implemented based on logic gate circuits, or it can be implemented based on flip-flops (e.g., D flip-flops), or it can be implemented based on a microcontroller. For example, the first timing circuit 1011 can be a non-overlapping circuit that can output multiple (e.g., two) non-overlapping first timing signals.

[0045] Figure 2This is a schematic diagram of the non-overlapping circuit structure in some embodiments of this specification. The non-overlapping circuit may include an inverter 10111, a buffer 10112, a NOR gate 10113, a NOR gate 10114, a delay circuit 10115, a delay circuit 10116, a buffer 10117, and a buffer 10118. The clock signal CLK is inverted by the inverter 10111 to obtain the signal... The clock signal CLK is buffered by buffer 10112 to obtain the signal. The output signal of NOR gate 10113 is The output signal of the NOR gate 10114 is... Signal C, after passing through delay circuit 10115, yields signal E. Delay circuit 10115 is formed by cascading multiple buffers. Signal E, after passing through buffer 10117, yields signal PHI1. Signal D, after passing through delay circuit 10116, yields signal F. Delay circuit 10116 is formed by cascading multiple buffers. Signal F, after passing through buffer 10118, yields signal PHI1. Thus, through the cross-feedback of NOR gates 10113 and 10114, complementarity between signals PHI1 and PHI2 can be achieved; through the delay of delay circuits 10115 and 10116, non-overlapping between signals PHI1 and PHI2 can be achieved.

[0046] In some embodiments, the current of the first timing signal output by the first timing circuit 1011 is relatively small, making it difficult to directly drive the components in the signal generation circuit 102. Therefore, the first timing signal output by the first timing circuit 1011 can be provided to the first driving circuit 1012. The first driving circuit 1012 can amplify the first timing signal (e.g., amplify the current of the first timing signal), thereby improving the load driving capability of the first timing signal. The first driving circuit 1012 can be implemented based on discrete components (such as switching transistors), or it can be implemented based on an application-specific integrated circuit (ASIC) or a microcontroller.

[0047] Figure 3 These are schematic diagrams of the drive circuits in some embodiments of this specification. For example... Figure 3As shown. The first driving circuit 1012 includes switching transistors 10121 and 10122. Switching transistor 10121 is an NPN transistor. Switching transistor 10122 is a PNP transistor. The bases of switching transistors 10121 and 10122 are electrically connected, serving as the input terminal of the first driving circuit 1012. The emitters of switching transistors 10121 and 10122 are electrically connected, serving as the output terminal of the first driving circuit 1012. The collector of switching transistor 10121 can be connected to a power supply. The collector of switching transistor 10122 can be grounded. The input terminal of the first driving circuit 1012 can be used to input a first timing signal. The output terminal of the first driving circuit 1012 can be used to output an amplified first control signal.

[0048] In some embodiments, the signal generation circuit 102 includes multiple components (such as switching transistors). These components can switch their operating states according to a first control signal, enabling the signal generation circuit 102 to output a drive signal. The signal generation circuit 102 can be a full-bridge circuit (also known as an H-bridge circuit). For example... Figure 1 The signal generation circuit 102 in the diagram is a full-bridge circuit. Of course, the signal generation circuit 102 can also be other circuits, such as a half-bridge circuit, a push-pull circuit, or an application-specific integrated circuit.

[0049] In some embodiments, the voltage of the drive signal is in a small range (e.g., 0.9V~5V). The drive signal output by the signal generation circuit 102 can be provided to the first boost circuit 200. The first boost circuit 200 can boost the drive signal to output an excitation signal. The voltage of the excitation signal is in a large range (e.g., 20V~30V). The voltage of the excitation signal is higher than that of the drive signal. The excitation signal can excite the transducer 300 to emit ultrasonic waves. The waveform of the excitation signal can be, for example, a square wave, a triangular wave, a sine wave, etc. The waveform of the excitation signal can be the same as or different from that of the drive signal. For example, the first boost circuit 200 can be a resonant circuit (also called a tuning circuit). The resonant circuit can include an LC resonant circuit. An LC resonant circuit includes one or more inductors and one or more capacitors. An LC resonant circuit can include an LC series resonant circuit and an LC parallel resonant circuit. The LC resonant circuit can boost the drive signal by a certain multiple (e.g., N times, where N is greater than 1). The resonant circuit described above is just an example. In practical applications, the first boost circuit 200 can also be other boost circuits, such as transformers, DC-DC converters, etc.

[0050] For example, please see Figure 4The LC resonant circuit includes inductor 201, capacitor 202, inductor 203, and resistor 204. Inductor 201 and capacitor 202 are connected in parallel and then in series with inductor 203 and resistor 204. The ultrasonic transmitting circuit 100 has two output terminals. These two output terminals output two square waves. Each output terminal can output one or more square waves, for example, 1-100 square waves. The number of square waves output by each output terminal is controllable. The frequency of the square waves output by each output terminal is controllable. The two square waves have the same waveform, amplitude, and frequency, but different phases. The frequency range of the two square waves is 6MHz-50MHz. The voltage amplitude range of the two square waves is 0.9V~5V. One of the two square waves is input to inductor 201, and the other is input to capacitor 202. The two square waves can be converted into a high-voltage sine wave through the LC resonant circuit. Resistor 204 can output a sine wave. The voltage amplitude range of the sine wave is 20V~30V. exist Figure 4 In the diagram, the inductance of inductor 201 can be represented as L1, the capacitance of capacitor 202 as C1, the inductance of inductor 203 as L2, the resistance of resistor 204 as R, and the capacitance of capacitor 301 as C2. The voltage applied to transducer 300 (capacitor 301) can be represented as... . . . The voltage of the excitation signal is represented by E, the voltage of the drive signal is represented by ω, and the angular frequency is represented by ω = 2πf, where f represents the frequency. Capacitor 301 can be the equivalent capacitance of transducer 300. Inductor 201, capacitor 202, inductor 203, and capacitor 301 can form a coupled double resonant circuit, thus having two resonant points. and . This is the resonant point of the resonant circuit corresponding to inductor 201 and capacitor 202. This refers to the resonant point of the resonant circuit corresponding to inductor 203 and capacitor 301. The frequency of the driving signal. With resonance point and resonance point Matching. Matching can be, for example, the frequency of the drive signal. Near the resonance point and At the frequency of the driving signal Near the resonance point and At that time, the drive signal can be... To achieve a significant boost in voltage. It can include: equal , and The difference is less than or equal to the set threshold. The frequency of the drive signal. The area near the resonance point may include: equal , and The difference is less than or equal to the set threshold. equal , and The difference is less than or equal to a set threshold. In practical applications, the frequency of the drive signal can be determined. And the capacitance value C2 of capacitor 301; it can be based on L1, C1, and L2 are determined by C2. For example, C1 can be determined based on business requirements (such as process, cost, impedance matching, etc.); C2 can be determined based on... C1 and C2, using formula Calculate L1 and L2; based on calculate . The multiple between E and the voltage can be the voltage amplification factor N of the first boost circuit 200.

[0051] It should be noted that, Figure 1 , Figure 4 , Figure 5 , Figure 9 , Figure 11 , Figure 12 and Figure 13 The LC resonant circuit shown is merely an example to visually illustrate the resonant circuit structure composed of inductors and capacitors. In practical engineering applications, LC resonant circuits manifest in various forms, and many different resonant circuit structures are derived according to specific needs. These different resonant circuit structures are also within the scope of disclosure and protection of this specification.

[0052] The voltage amplitude of the excitation signal output by the first boost circuit 200 is positively correlated with the voltage swing. The voltage swing is the difference between the maximum and minimum voltage values ​​of the drive signal. For example, the voltage amplitude of the excitation signal is N times the voltage swing. N can be a fixed value. Alternatively, N can be a value within a certain range, and thus can vary.

[0053] In some embodiments, transducer 300, also referred to as an ultrasonic transducer, is used to convert between electrical signals and ultrasonic waves. Transducer 300 can convert the excitation signal output from the first boost circuit 200 into mechanical vibration, thereby emitting ultrasonic waves. Transducer 300 can also convert ultrasonic waves into electrical signals (such as ultrasonic signals). Transducer 300 can be a single transducer, or it can be a transducer array containing multiple transducers. The transducer array allows control of the transmission and / or reception direction of the ultrasonic signal, improving resolution and extending the detection range of the ultrasonic waves.

[0054] In some embodiments, with Figure 1 Taking the signal generation circuit 102 as an example, the signal generation circuit 102 may include switching transistors P1, P2, N1, and N2. The first control circuit 101 outputs two first control signals. One first control signal controls switching transistors P1 and N2, and the other first control signal controls switching transistors P2 and N1. The signal generation circuit 102 includes two output terminals, thus outputting two drive signals, DRVP and DRVN. The two drive signals have the same waveform and frequency but different phases. The waveform of the drive signal can be, for example, a square wave. During the first half-cycle of one period of the first control signal, switching transistors P1 and N2 are turned on, and switching transistors P2 and N1 are turned off. DRVP is high and DRVN is low. During the second half-cycle of one period of the first control signal, switching transistors P2 and N1 are turned on, and switching transistors P1 and N2 are turned off. DRVN is high and DRVP is low. The drive signals DRVP and DRVN can drive the first boost circuit 200 so that the first boost circuit 200 outputs an excitation signal.

[0055] For example, the high-side voltage VP of the signal generation circuit 102 is AVDD. AVDD is the output voltage of the power supply. The power supply can be a DC power supply. The low-side voltage VN of the signal generation circuit 102 is AVSS. AVSS is the voltage of the reference ground of the signal generation circuit 102. AVSS can be 0, for example. Then the voltage range of the drive signal DRVP can be AVDD~AVSS, and the voltage amplitude range of the drive signal DRVN can be AVSS~AVDD. The voltage amplitude of the excitation signal output by the first boost circuit 200 can be expressed as Vtx = N × AVDD. N is the voltage amplification factor of the first boost circuit 200.

[0056] In some embodiments, please refer to Figure 5The ultrasonic transmitting circuit 100 may include a second boost circuit 103. The second boost circuit 103 is electrically connected to the power supply and the high-side of the signal generation circuit 102. The second boost circuit 103 can boost the output voltage AVDD of the power supply, thereby increasing the high-side voltage of the signal generation circuit 102. By increasing the high-side voltage of the signal generation circuit 102, the voltage swing of the drive signal output by the signal generation circuit 102 can be increased. The voltage swing is the difference between the maximum and minimum voltage values ​​of the drive signal. By increasing the voltage swing of the drive signal, the voltage amplitude of the excitation signal output by the first boost circuit 200 can be increased. This voltage amplitude is positively correlated with the voltage swing. This increases the intensity of the mechanical vibration of the transducer 300, allowing the transducer 300 to output higher-energy ultrasonic waves. The ultrasonic waves are reflected upon encountering the object being detected (e.g., a fingerprint). The ultrasonic receiving circuit 400 can receive higher-energy echoes. The signal amplitude detected by the ultrasonic receiving circuit 400 increases. The sensitivity and signal-to-noise ratio of ultrasonic detection are improved.

[0057] The second boost circuit 103 may include a voltage doubler, a charge pump, a boost converter, etc. Figure 5 Taking the signal generation circuit 102 as an example, the second boost circuit 103 can boost the high-side voltage VP of the signal generation circuit 102 to M×AVDD. M is greater than 1. Therefore, the voltage amplitude range of the drive signal DRVP output by the signal generation circuit 102 is M×AVDD~AVSS, and the voltage amplitude range of the output drive signal DRVN is AVSS~M×AVDD. The voltage amplitude of the excitation signal output by the first boost circuit 200 is Vtx=M×N×AVDD.

[0058] In some embodiments, the ultrasonic transmitting circuit 100 may include a second control circuit 104. The second control circuit 104 is electrically connected to the second boost circuit 103. The second control circuit 104 is used to output a second control signal. The waveform of the second control signal can be a square wave, a triangle wave, a sine wave, etc. The second control signal can be a periodic timing control signal used to control the operating timing of the second boost circuit 103. For example, the second control signal is used to control the operating state of the components in the second boost circuit 103 (e.g., controlling the on and off states of the switching transistor). The second boost circuit 103 can output a boosted high-side voltage according to the second control signal. The signal generation circuit 102 can output a drive signal with increased voltage swing according to the boosted high-side voltage. The first boost circuit 200 can output an excitation signal with increased voltage according to the drive signal with increased voltage swing. The excitation signal with increased voltage can increase the intensity of the mechanical vibration of the transducer 300, thereby outputting ultrasonic waves with higher energy.

[0059] For example, the second control circuit 104 may include a second timing circuit and a second drive circuit. The second timing circuit is electrically connected to the second drive circuit. The second drive circuit is electrically connected to the second boost circuit 103. The second timing circuit can output a second timing signal. The waveform of the second timing signal can be a square wave, a triangle wave, a sine wave, etc. The second drive circuit can amplify the second timing signal to improve the load driving capability, thereby outputting an amplified second control signal. The circuit structure of the second timing circuit can be referred to the first timing circuit 1011, and will not be repeated here. For example, the second timing circuit can be a non-overlapping circuit. The circuit structure of the second drive circuit can be referred to the first drive circuit 1012, and will not be repeated here.

[0060] For example, the second control circuit 104 can also be a clock circuit. The second control signal is a clock signal.

[0061] In some embodiments, the second boost circuit 103 can be a voltage multiplier. The voltage multiplier may include a switching transistor and a capacitor. The voltage multiplier can charge the capacitor using the output voltage of the power supply and, by switching the switching transistor, boost the output voltage by a factor of M (e.g., 2x, 4x, etc.). See also Figure 6The voltage multiplier may include switching transistors Pv1, Pv2, Nv1, and Nv2, and capacitors C1 and C2. Switches Pv1, Pv2, Nv1, and Nv2 form a full-bridge circuit. The full-bridge circuit includes a first bridge arm and a second bridge arm. The first bridge arm includes switching transistors Pv1 and Nv1 connected in series. The second bridge arm includes switching transistors Pv2 and Nv2 connected in series. Capacitor C1 is connected to the midpoint of the first and second bridge arms. The high-side terminals of both the first and second bridge arms are electrically connected to a power supply, and the low-side terminals of both bridge arms are grounded through capacitor C2. Capacitor C2 is electrically connected to the high-side terminal of signal generation circuit 102 to power the signal generation circuit 102. Capacitor C2 is used to output the boosted high-side voltage from signal generation circuit 102. The second control circuit 104 outputs two second control signals. One second control signal controls switching transistors Pv1 and Nv2, and another second control signal controls switching transistors Pv2 and Nv1. During the first half of the cycle of each second control signal, switching transistors Pv2 and Nv1 are turned on, and Pv1 and Nv2 are turned off. At this time, the power supply (power), the turned-on switching transistor Pv2, capacitor C1, the turned-on switching transistor Nv1, capacitor C2, and ground form a circuit. Since the end of capacitor C1 connected to the midpoint of the first bridge arm is grounded, and the end of capacitor C1 connected to the midpoint of the second bridge arm is connected to the power supply (power), the output voltage of power supply (AVDD) causes capacitor C1 to be charged with charge Q. Because charge in the circuit cannot be created or destroyed, the current from the charging of capacitor C1 flows synchronously through capacitor C2, causing capacitor C2 to also be charged with charge Q. During the second half of the cycle of each second control signal, switching transistors Pv2 and Nv1 are turned off, and Pv1 and Nv2 are turned on. At this time, the charge on capacitor C1 will be transferred to capacitor C2, which has a charge of 2Q and a voltage of 2×AVDD. Capacitor C2 is used to power the signal generation circuit 102.

[0062] The voltage multiplier can boost the high-side voltage VP of the signal generation circuit 102 to 2×AVDD. The voltage amplitude range of the drive signal DRVP output by the signal generation circuit 102 is 2×AVDD to AVSS, and the voltage amplitude range of the drive signal DRVN output by the signal generation circuit 102 is AVSS to 2×AVDD. The voltage amplitude of the excitation signal output by the first boost circuit 200 is Vtx = 2×N×AVDD.

[0063] It should be noted that, Figure 6 The voltage multiplier shown is merely an example. With other circuit structures for the voltage multiplier, the output voltage AVDD of the power supply can be boosted by other factors, and the first boost circuit 200 can also output other voltage amplitudes.

[0064] In some embodiments, the second boost circuit 103 can be a charge pump. The charge pump can include diodes and capacitors. The charge pump accumulates and transfers charge through capacitors and switches, boosting the output voltage by M times (e.g., 2 times, 4 times, etc.). The charge pump can include multiple diodes connected in series. The output of each diode is electrically connected to one end of a capacitor. The input of the first diode is electrically connected to a power supply. The other end of the capacitor connected to the output of the last diode is grounded. The second control circuit 104 outputs two second control signals, Signal1 and Signal2. Except for the capacitor connected to the output of the last diode, the other end of the capacitor connected to the output of each diode is connected to the second control signal Signal1, and the other end of the capacitor connected to the output of the remaining diodes is connected to the second control signal Signal2. See also... Figure 7 The charge pump may include diodes D1, D2, D3, D4, and D5, and capacitors C1a, C2a, C1b, C2b, and C3. Diodes D1, D2, D3, D4, and D5 are connected in series. The input terminal of diode D1 is electrically connected to the power supply, and its output terminal is electrically connected to one end of capacitor C1a. The output terminal of diode D2 is electrically connected to one end of capacitor C2a. The output terminal of diode D3 is electrically connected to one end of capacitor C1b. The output terminal of diode D4 is electrically connected to one end of capacitor C2b. The output terminal of diode D5 is electrically connected to one end of capacitor C3. The other ends of capacitors C1a and C1b are electrically connected to the second control signal Signal1, and the other ends of capacitors C2a and C2b are electrically connected to the second control signal Signal2. The other end of capacitor C3 is grounded. The waveforms, amplitudes, and frequencies of the second control signals Signal1 and Signal2 are the same, but their phases may differ. For example, the phase difference between the second control signal Signal1 and the second control signal Signal2 can be, for example, 180 degrees. When the second control signal Signal1 is high and the second control signal Signal2 is low, the voltage across capacitor C1a is the output voltage AVDD of the power supply. When the second control signal Signal1 is low and the second control signal Signal2 is high, the voltage across capacitor C2a is 2 × AVDD. And so on, the voltage across capacitor C3 is 4 × AVDD. Capacitor C3 is used to power the signal generation circuit 102.

[0065] The charge pump can boost the high-side voltage VP of the signal generation circuit 102 to 4×AVDD. The voltage amplitude range of the drive signal DRVP output by the signal generation circuit 102 is 4×AVDD to AVSS, and the voltage amplitude range of the drive signal DRVN output by the signal generation circuit 102 is AVSS to 4×AVDD. The voltage amplitude of the excitation signal output by the first boost circuit 200 is Vtx = 4×N×AVDD.

[0066] It should be noted that, Figure 7 The charge pump shown is merely an example. With other circuit structures for the charge pump, the output voltage AVDD of the power supply can be boosted by other factors, and the first boost circuit 200 can also output other voltage amplitudes.

[0067] In some embodiments, the second boost circuit 103 may be a boost chopper circuit. See also... Figure 8 The boost chopper circuit may include a switch P3, an inductor L3, a diode D6, and a capacitor C4. Inductor L3, diode D6, and capacitor C4 are connected in series. The switch P3, diode D6, and capacitor C4 are connected in parallel. A second control circuit 104 outputs a second control signal. The second control signal can be, for example, a clock signal. The second control signal controls the on / off state of switch P3. When the second control signal is high, switch P3 is on, and the power supply, inductor L3, and switch P3 form a loop. The voltage across switch P3 is the output voltage AVDD of the power supply, and diode D6 is also on. At this time, the voltage across capacitor C4 is AVDD. The current in inductor L3 gradually increases, storing energy E. When the second control signal is low, the current in inductor L3 is charged into capacitor C4 through diode D6, and the energy E stored in inductor L3 is transferred to capacitor C4. The voltage across capacitor C4 can increase to M times AVDD. This process repeats. The voltage across capacitor C4 can be determined by the duty cycle of the second control signal. Capacitor C4 is used to power the signal generation circuit 102.

[0068] In some embodiments, please refer to Figure 9The ultrasonic transmitting circuit 100 may include a step-down circuit 105. The step-down circuit 105 is electrically connected to the signal generation circuit 102. The step-down circuit 105 reduces the low-side voltage of the signal generation circuit 102. By reducing the low-side voltage of the signal generation circuit 102, the voltage swing of the drive signal output by the signal generation circuit 102 can be increased. The voltage swing is the difference between the maximum and minimum voltage values ​​of the drive signal. By increasing the voltage swing of the drive signal, the voltage amplitude of the excitation signal output by the first boost circuit 200 can be increased. Thus, the transducer 300 can output ultrasonic waves with higher energy. The ultrasonic waves are reflected upon encountering the object being detected. The ultrasonic receiving circuit 400 can receive the echo with higher energy. The signal amplitude detected by the ultrasonic receiving circuit 400 increases. The sensitivity and signal-to-noise ratio of ultrasonic detection are both improved.

[0069] For example, the buck converter 105 can reduce the low-side voltage of the signal generation circuit 102 to VN = -Y × AVDD, where Y is an integer greater than or equal to 1. The voltage amplitude range of the output drive signal DRVP from the signal generation circuit 102 is AVDD to -Y × AVDD, and the voltage amplitude range of the output drive signal DRVN is -Y × AVDD to AVDD. The voltage amplitude of the excitation signal output by the first boost converter 200 is Vtx = (1 + Y) × N × AVDD, where AVDD is the output voltage of the power supply.

[0070] In some embodiments, the ultrasonic transmitting circuit 100 may further include a third control circuit 106. The third control circuit 106 is electrically connected to the buck circuit 105. The third control circuit 106 is used to output a third control signal. The waveform of the third control signal can be a square wave, a triangle wave, a sine wave, etc. The third control signal can be a periodic timing control signal used to control the operating timing of the buck circuit 105. For example, the third control signal is used to control the operating state of the components in the buck circuit 105 (e.g., controlling the on and off states of the switching transistor). The buck circuit 105 can output a lower voltage after bucking down according to the third control signal. The signal generation circuit 102 can output a drive signal with increased voltage swing according to the lower voltage after bucking down. The first boost circuit 200 can output an excitation signal with increased voltage according to the drive signal with increased voltage swing. The excitation signal with increased voltage can increase the intensity of the mechanical vibration of the transducer 300, thereby outputting ultrasonic waves with higher energy.

[0071] For example, the third control circuit 106 may include a third timing circuit and a third drive circuit. The third timing circuit is electrically connected to the third drive circuit. The third drive circuit is electrically connected to the buck circuit 105. The third timing circuit can output a third timing signal. The waveform of the third timing signal can be a square wave, a triangle wave, a sine wave, etc. The third drive circuit can amplify the third timing signal to improve the load driving capability, thereby outputting an amplified third control signal. The circuit structure of the third timing circuit can be referred to the first timing circuit 1011, and will not be described again here. The circuit structure of the third drive circuit can be referred to the first drive circuit 1012, and will not be described again here.

[0072] For example, the third control circuit 106 can also be a clock circuit. The third control signal is a clock signal.

[0073] In some embodiments, please refer to Figure 10The step-down circuit 105 may include switching transistors Pv1, Pv2, Nv1, and Nv2, and capacitors C1 and C2. Switches Pv1, Pv2, Nv1, and Nv2 form a full-bridge circuit. The full-bridge circuit includes a first bridge arm and a second bridge arm. The first bridge arm includes switching transistors Pv1 and Nv1 connected in series. The second bridge arm includes switching transistors Pv2 and Nv2 connected in series. Capacitor C1 is connected to the midpoint of the first bridge arm and the midpoint of the second bridge arm. The high end of the first bridge arm is electrically connected to the power supply, and the low end of the first bridge arm is used to output the low-side voltage VN of the signal generation circuit 102. Both ends of the second bridge arm are grounded, and the midpoint of the second bridge arm is grounded through capacitor C2. The second control circuit 104 outputs two second control signals. One second control signal controls switching transistors Pv1 and Pv2, and the other second control signal controls switching transistors Nv1 and Nv2. During the first half of the second control signal cycle, switches Pv1 and Pv2 are turned on, while switches Nv1 and Nv2 are turned off. At this time, one end of capacitor C1 is connected to the power supply through switch Pv1, and the other end is grounded through switch Pv2. Capacitor C1 is charged to AVDD. During the second half of the second control signal cycle, switches Pv1 and Pv2 are turned off, while switches Nv1 and Nv2 are turned on. One end of capacitor C1 is grounded through switch Nv2, and the other end provides VN through switch Nv1. Since the voltage of capacitor C1 cannot change abruptly, when one end of capacitor C1 is pulled to ground, the voltage at the other end becomes 0 - AVDD = -AVDD. Thus, the buck converter 105 can output VN = -AVDD. The voltage amplitude range of the drive signal DRVP output by signal generation circuit 102 is AVDD to -AVDD, and the voltage amplitude range of the drive signal DRVN output is -AVDD to AVDD. The voltage amplitude of the excitation signal output by the first boost circuit 200 is Vtx = 2 × N × AVDD. AVDD is the output voltage of the power supply.

[0074] It should be noted that, Figure 10 The step-down circuit shown is merely an example. When the step-down circuit has other circuit structures, the ground voltage of the signal generation circuit 102 can be reduced to other values, and the first boost circuit 200 can also output other voltage amplitudes.

[0075] In some embodiments, please refer to Figure 11The ultrasonic transmitting circuit 100 may include a second boost circuit 103 and a buck circuit 105. The second boost circuit 103 is electrically connected to the power supply and the signal generation circuit 102. The second boost circuit 103 can boost the output voltage AVDD of the power supply, thereby increasing the high-side voltage of the signal generation circuit 102. The buck circuit 105 can decrease the low-side voltage of the signal generation circuit 102. Thus, by simultaneously increasing the high-side power supply and decreasing the low-side voltage of the signal generation circuit 102, the voltage swing of the drive signal output by the signal generation circuit 102 can be further increased. The voltage swing is the difference between the maximum and minimum voltage values ​​of the drive signal. By increasing the voltage swing of the drive signal, the voltage amplitude of the excitation signal output by the first boost circuit 200 can be increased. This can increase the intensity of the mechanical vibration of the transducer 300, enabling the transducer 300 to output higher-energy ultrasonic waves. The ultrasonic waves will be reflected after encountering the object being detected. The ultrasonic receiving circuit 400 can receive the higher-energy echo. The signal amplitude detected by the ultrasonic receiving circuit 400 is increased. The sensitivity and signal-to-noise ratio of ultrasonic detection are both improved.

[0076] For example, the second boost circuit 103 can boost the high-side voltage VP of the signal generation circuit 102 to M×AVDD. The buck circuit 105 can reduce the low-side voltage of the signal generation circuit 102 to VN=-Y×AVDD. M is greater than 1. Y is greater than or equal to 1. Then the voltage amplitude range of the drive signal DRVP output by the signal generation circuit 102 is M×AVDD to -Y×AVDD, and the voltage amplitude range of the drive signal DRVN output by the signal generation circuit 102 is -Y×AVDD to M×AVDD. The voltage amplitude of the excitation signal output by the first boost circuit 200 is Vtx=(M+Y)×N×AVDD.

[0077] In some embodiments, the ultrasonic transmitting circuit 100 may further include a second control circuit 104 and a third control circuit 106. The second control circuit 104 is electrically connected to the second boost circuit 103. The second control circuit 104 is used to output a second control signal. The waveform of the second control signal can be a square wave, a triangle wave, a sine wave, etc. The second control signal can be a periodic timing control signal used to control the operating timing of the second boost circuit 103. For example, the second control signal is used to control the operating state of the components in the second boost circuit 103 (e.g., controlling the on and off states of the switching transistors). The second boost circuit 103 can output a boosted high-side voltage according to the second control signal. The third control circuit 106 is electrically connected to the buck circuit 105. The third control circuit 106 is used to output a third control signal. The waveform of the third control signal can be a square wave, a triangle wave, a sine wave, etc. The third control signal can be a periodic timing control signal used to control the operating timing of the buck circuit 105. For example, the third control signal is used to control the operating state of the components in the buck circuit 105 (e.g., controlling the on and off states of the switching transistors). The step-down circuit 105 can output the stepped-down low-end voltage according to the third control signal.

[0078] Please see Figure 12 This specification also provides an ultrasonic transmitting chip 1. The ultrasonic transmitting chip 1 may include one or more of a first control circuit 101, a second control circuit 104, a third control circuit 106, a transducer 300, and an ultrasonic receiving circuit 400. The ultrasonic receiving circuit 400 may include an amplification circuit and a waveform conversion circuit. The transducer 300 can receive ultrasonic waves and output an ultrasonic signal. The ultrasonic signal output by the transducer 300 can be an analog signal. The ultrasonic signal output by the transducer 300 is relatively weak. The amplification circuit can amplify the ultrasonic signal output by the transducer 300 to obtain an amplified ultrasonic signal. The amplification circuit may include a single-stage amplification circuit, or it may include a multi-stage amplification circuit. The amplification circuit may be based on an operational amplifier. The waveform of the amplified ultrasonic signal is irregular and contains noise. The waveform conversion circuit can shape the amplified ultrasonic signal and output a shaped ultrasonic signal. The waveform conversion circuit may include a voltage comparator, a Schmitt trigger, etc. The shaped ultrasonic signal can be used as an input to subsequent circuits. For example, the shaped ultrasonic signal can be provided to an analog-to-digital converter circuit. An analog-to-digital converter (ADC) can convert the shaped ultrasonic signal into a digital signal. The digital signal output by the ADC can then be processed by a processor.

[0079] The ultrasonic transmitting chip 1 does not include signal generation circuit 102, second boost circuit 103, buck circuit 105, first boost circuit 200, etc.

[0080] This specification provides a driver chip 2. The driver chip 2 may include one or more of a signal generation circuit 102, a second boost circuit 103, and a buck circuit 105. The driver chip 2 is used to drive the ultrasonic transmitting chip 1.

[0081] The driver chip 2 does not include the first control circuit 101, the second control circuit 104, the third control circuit 106, the transducer 300, the ultrasonic receiving circuit 400, etc.

[0082] Therefore, the signal generation circuit 102, the second boost circuit 103, and the buck circuit 105 are integrated into the driver chip 2. The first control circuit 101, the second control circuit 104, the third control circuit 106, the transducer 300, and the ultrasonic receiving circuit 400 are integrated into the ultrasonic transmitting chip 1. By separating the signal generation circuit 102 from the transducer 300 and the ultrasonic receiving circuit 400 (integrating them into different chips), the influence of the signal output from the signal generation circuit 102 on the transducer 300 and the ultrasonic receiving circuit 400 can be reduced, thereby improving the sensitivity and signal-to-noise ratio of ultrasonic detection.

[0083] The first boost circuit 200 is located outside the ultrasonic transmitting chip 1 and the driving chip 2, and is an off-chip circuit. The driving chip 2 is used to output a driving signal according to the control signal (such as one or more of the first control signal, second control signal, third control signal, etc.) output by the ultrasonic transmitting chip 1. The first boost circuit 200 can boost the driving signal to obtain an excitation signal. The transducer 300 in the ultrasonic transmitting chip 1 can emit ultrasonic waves under the action of the excitation signal.

[0084] This specification provides an ultrasonic module 3. The ultrasonic module 3 includes an ultrasonic emitting chip 1, a driving chip 2, and a first boost circuit 200. The ultrasonic emitting chip 1 and the driving chip 2 can be electrically connected via a printed circuit board (e.g., a flexible printed circuit board). The ultrasonic module 3 can be applied to fingerprint recognition scenarios. The driving chip 2 can drive the ultrasonic emitting chip 1 to emit ultrasonic waves. The ultrasonic waves are reflected upon encountering a fingerprint. Fingerprints are lines of raised and recessed areas on the skin. The reflectivity of raised and recessed areas differs. When ultrasonic waves encounter the raised and recessed areas of a fingerprint, the reflected ultrasonic waves differ in time and intensity. The ultrasonic emitting chip 1 can receive the reflected ultrasonic waves; the structural features of the fingerprint can be identified based on the reflected ultrasonic waves. Of course, the ultrasonic module 3 can also be applied to other scenarios, such as medical imaging.

[0085] Please see Figure 13This specification also provides another ultrasonic transmitting chip 4 in its embodiments. The ultrasonic transmitting chip 4 may include one or more of the following: a first control circuit 101, a signal generation circuit 102, a second boost circuit 103, a second control circuit 104, a buck circuit 105, a third control circuit 106, a transducer 300, and an ultrasonic receiving circuit 400. By centrally deploying the signal generation circuit 102, the transducer 300, and the ultrasonic receiving circuit 400 (integrating them into the same chip), packaging costs can be reduced. Furthermore, centrally deploying the signal generation circuit 102, the transducer 300, and the ultrasonic receiving circuit 400 can also reduce the size and complexity of the ultrasonic module 5, facilitating the miniaturization of electronic devices. For example, in the ultrasonic module 5, it is no longer necessary to connect two separate chips via a printed circuit board, thereby reducing the size and complexity of the ultrasonic module 5.

[0086] The first boost circuit 200 is located outside the ultrasonic transmitter chip 4 and is an off-chip circuit of the ultrasonic transmitter chip 4.

[0087] This specification also provides another ultrasonic module 5. The ultrasonic module 5 includes an ultrasonic transmitting chip 4 and a first boost circuit 200. The ultrasonic module 5 can be applied to fingerprint recognition scenarios. The ultrasonic transmitting chip 4 can emit ultrasonic waves. These ultrasonic waves are reflected upon encountering a fingerprint. Fingerprints are lines of raised and recessed areas on the skin. The reflectivity of the raised and recessed areas differs. When ultrasonic waves encounter the raised and recessed areas of a fingerprint, the reflected ultrasonic waves differ in time and intensity. The ultrasonic transmitting chip 4 can receive the reflected ultrasonic waves; the structural features of the fingerprint can be identified based on the reflected ultrasonic waves. Of course, the ultrasonic module 5 can also be applied to other scenarios, such as medical imaging.

[0088] This specification also provides an electronic device. The electronic device may include, for example, a smartphone, a smart lock, etc.

[0089] As an example, the electronic device may include an ultrasonic module 3 and a processor. The ultrasonic transmitting chip 1 in the ultrasonic module 3 may be electrically connected to the processor. For example, the ultrasonic transmitting chip 1 in the ultrasonic module 3 may be electrically connected to the processor via a printed circuit board (e.g., a flexible printed circuit board). The ultrasonic receiving circuit 400 may output a digital signal to the processor based on the received echo. The processor may process the digital signal output by the ultrasonic receiving circuit 400.

[0090] As another example, the electronic device may include an ultrasonic module 5 and a processor. The ultrasonic transmitting chip 4 in the ultrasonic module 5 may be electrically connected to the processor. For example, the ultrasonic transmitting chip 4 in the ultrasonic module 5 may be electrically connected to the processor via a printed circuit board (e.g., a flexible printed circuit board). The ultrasonic receiving circuit 400 may output a digital signal to the processor based on the received echo. The processor may process the digital signal output by the ultrasonic receiving circuit 400.

[0091] This specification provides an ultrasonic transmitting circuit. The ultrasonic transmitting circuit includes a non-overlapping circuit, a driving circuit, and a full-bridge circuit connected in sequence. The full-bridge circuit is connected to a resonant circuit. The resonant circuit is connected to an ultrasonic transducer.

[0092] The non-overlapping circuit is used to output a non-overlapping signal to the driving circuit. The driving circuit is used to output a first control signal to the full-bridge circuit based on the non-overlapping signal. The full-bridge circuit is used to output a driving signal to the resonant circuit based on the first control signal. The resonant circuit is used to output an excitation signal to the ultrasonic transducer based on the driving signal. The voltage of the excitation signal is higher than that of the driving signal. For example, the voltage of the driving signal is in a smaller range (e.g., 0.9V~5V), while the voltage of the excitation signal is in a larger range (e.g., 20V~30V). The voltage amplitude of the excitation signal is higher than that of the driving signal. The ultrasonic transducer is used to emit ultrasonic waves based on the excitation signal.

[0093] The non-overlapping circuit, the driving circuit, the full-bridge circuit, and the ultrasonic transducer are located on the ultrasonic transmitting chip, and the resonant circuit is an off-chip circuit of the ultrasonic transmitting chip. Alternatively, the non-overlapping circuit, the driving circuit, and the ultrasonic transducer are located on the ultrasonic transmitting chip, the full-bridge circuit is located on the driving chip, and the resonant circuit is an off-chip circuit of both the ultrasonic transmitting chip and the driving chip.

[0094] In some embodiments, the ultrasonic transmitting circuit may further include at least one of a second boost circuit and a buck circuit. The second boost circuit is used to boost the high-side voltage of the full-bridge circuit. The buck circuit is used to buck the low-side voltage of the full-bridge circuit. The full-bridge circuit is used to output a drive signal with an increased voltage swing to the resonant circuit according to at least one of the following: the boosted high-side voltage, and the bucked low-side voltage. The voltage swing is the difference between the maximum and minimum voltage values ​​of the drive signal.

[0095] The functional units in the embodiments of this specification can be integrated into one processing unit, or each functional unit can exist physically separately, or two or more functional units can be integrated into one processing unit.

[0096] Those skilled in the art will understand that the descriptions of the various embodiments in this specification have different focuses, and parts not described in detail in a certain embodiment can be referred to in the relevant descriptions of other embodiments. Furthermore, it is understood that those skilled in the art, after reading this specification, can conceive of any combination of some or all of the embodiments listed in this specification without creative effort, and such combinations are also within the scope of disclosure and protection of this specification.

[0097] Although this specification has been described through embodiments, those skilled in the art will understand that the above embodiments are merely illustrative of the core ideas of this specification. Those skilled in the art will appreciate that many variations and modifications are possible with this specification. It is intended that the appended claims encompass these variations and modifications without departing from the spirit of this specification.

Claims

1. An ultrasonic transmitting circuit, characterized in that, Includes a first control circuit and a signal generation circuit; The first control circuit is connected to the signal generation circuit and is used to output a first control signal and transmit the first control signal to the signal generation circuit. The first control circuit includes a first timing circuit and a plurality of first driving circuits connected to the first timing circuit. The first timing circuit is used to output a plurality of first timing signals. The first driving circuit is used to amplify the first timing signals output by the first timing circuit to obtain a first control signal. The first control signals output by the plurality of first driving circuits are used to jointly drive the signal generation circuit. The signal generation circuit is connected to the first boost circuit and is used to output a drive signal according to the first control signal output by the plurality of first drive circuits, and to transmit the drive signal to the first boost circuit. The first control signals output by the plurality of first drive circuits do not overlap. The first boost circuit is connected to the ultrasonic transducer and is used to output an excitation signal according to the drive signal and to transmit the excitation signal to the ultrasonic transducer, wherein the voltage of the excitation signal is higher than that of the drive signal. The excitation signal is used to excite the ultrasonic transducer to emit ultrasonic waves. The first control circuit, the signal generation circuit, and the ultrasonic transducer are located on the ultrasonic transmitting chip, and the first boost circuit is an off-chip circuit of the ultrasonic transmitting chip. Alternatively, the first control circuit and the ultrasonic transducer are located on the ultrasonic transmitting chip, the signal generation circuit is located on the driving chip, and the first boost circuit is an off-chip circuit of the ultrasonic transmitting chip and the driving chip. The ultrasonic transmitting circuit also includes a second boost circuit; The second boost circuit is used to boost the high-side voltage of the signal generation circuit; The signal generation circuit is used to output a drive signal with increased voltage swing based on the boosted high-side voltage. The voltage swing is the difference between the maximum and minimum voltage values ​​of the drive signal.

2. The ultrasonic transmitting circuit according to claim 1, characterized in that, It also includes a second control circuit; The second control circuit is used to output a second control signal; The second boost circuit is used to boost the high-side voltage according to the second control signal.

3. The ultrasonic transmitting circuit according to claim 1 or 2, characterized in that, The high-side voltage after boosting by the signal generation circuit is M×AVDD, where M is the voltage amplification factor of the second boost circuit and AVDD is the output voltage of the power supply. The low-side voltage of the signal generation circuit is ground. The maximum voltage value of the drive signal is M×AVDD, and the minimum voltage value of the drive signal is ground. The voltage of the excitation signal is M×N×AVDD, where N is the voltage amplification factor of the first boost circuit.

4. An ultrasonic transmitting circuit, characterized in that, Includes a first control circuit and a signal generation circuit; The first control circuit is connected to the signal generation circuit and is used to output a first control signal and transmit the first control signal to the signal generation circuit. The first control circuit includes a first timing circuit and a plurality of first driving circuits connected to the first timing circuit. The first timing circuit is used to output a plurality of first timing signals. The first driving circuit is used to amplify the first timing signals output by the first timing circuit to obtain a first control signal. The first control signals output by the plurality of first driving circuits are used to jointly drive the signal generation circuit. The signal generation circuit is connected to the first boost circuit and is used to output a drive signal according to the first control signal output by the plurality of first drive circuits, and to transmit the drive signal to the first boost circuit. The first control signals output by the plurality of first drive circuits do not overlap. The first boost circuit is connected to the ultrasonic transducer and is used to output an excitation signal according to the drive signal and to transmit the excitation signal to the ultrasonic transducer, wherein the voltage of the excitation signal is higher than that of the drive signal. The excitation signal is used to excite the ultrasonic transducer to emit ultrasonic waves. The first control circuit, the signal generation circuit, and the ultrasonic transducer are located on the ultrasonic transmitting chip, and the first boost circuit is an off-chip circuit of the ultrasonic transmitting chip. Alternatively, the first control circuit and the ultrasonic transducer are located on the ultrasonic transmitting chip, the signal generation circuit is located on the driving chip, and the first boost circuit is an off-chip circuit of the ultrasonic transmitting chip and the driving chip. The ultrasonic transmitting circuit also includes a step-down circuit; The step-down circuit is used to step down the low-end voltage of the signal generation circuit. The signal generation circuit is used to output a drive signal with increased voltage swing based on the low-end voltage after step-down, wherein the voltage swing is the difference between the maximum and minimum voltage values ​​of the drive signal.

5. The ultrasonic transmitting circuit according to claim 4, characterized in that, It also includes a third control circuit; The third control circuit is used to output a third control signal; The step-down circuit is used to step down the low-end voltage according to the third control signal.

6. The ultrasonic transmitting circuit according to claim 4 or 5, characterized in that, The high-side voltage of the signal generation circuit is AVDD, and the low-side voltage of the signal generation circuit is -Y×AVDD, where Y is the voltage reduction factor of the buck circuit and AVDD is the output voltage of the power supply; the maximum voltage value of the drive signal is AVDD, and the minimum voltage value of the drive signal is -Y×AVDD; the voltage of the excitation signal is (1+Y)×N×AVDD, where N is the voltage amplification factor of the first boost circuit.

7. An ultrasonic transmitting circuit, characterized in that, Includes a first control circuit and a signal generation circuit; The first control circuit is connected to the signal generation circuit and is used to output a first control signal and transmit the first control signal to the signal generation circuit. The first control circuit includes a first timing circuit and a plurality of first driving circuits connected to the first timing circuit. The first timing circuit is used to output a plurality of first timing signals. The first driving circuit is used to amplify the first timing signals output by the first timing circuit to obtain a first control signal. The first control signals output by the plurality of first driving circuits are used to jointly drive the signal generation circuit. The signal generation circuit is connected to the first boost circuit and is used to output a drive signal according to the first control signal output by the plurality of first drive circuits, and to transmit the drive signal to the first boost circuit. The first control signals output by the plurality of first drive circuits do not overlap. The first boost circuit is connected to the ultrasonic transducer and is used to output an excitation signal according to the drive signal and to transmit the excitation signal to the ultrasonic transducer, wherein the voltage of the excitation signal is higher than that of the drive signal. The excitation signal is used to excite the ultrasonic transducer to emit ultrasonic waves. The first control circuit, the signal generation circuit, and the ultrasonic transducer are located on the ultrasonic transmitting chip, and the first boost circuit is an off-chip circuit of the ultrasonic transmitting chip. Alternatively, the first control circuit and the ultrasonic transducer are located on the ultrasonic transmitting chip, the signal generation circuit is located on the driving chip, and the first boost circuit is an off-chip circuit of the ultrasonic transmitting chip and the driving chip. The ultrasonic transmitting circuit also includes a second boost circuit and a buck circuit; The second boost circuit is used to boost the high-side voltage of the signal generation circuit; The step-down circuit is used to step down the low-end voltage of the signal generation circuit. The signal generation circuit is used to output a drive signal with increased voltage swing based on the boosted high-side voltage and the bucked low-side voltage. The voltage swing is the difference between the maximum and minimum voltage values ​​of the drive signal.

8. The ultrasonic transmitting circuit according to claim 7, characterized in that, It also includes a second control circuit and a third control circuit; The second control circuit is used to output a second control signal; The second boost circuit is used to boost the high-side voltage according to the second control signal; The third control circuit is used to output a third control signal; The step-down circuit is used to step down the low-end voltage according to the third control signal.

9. The ultrasonic transmitting circuit according to claim 7 or 8, characterized in that, The high-side voltage of the signal generation circuit is M×AVDD, and the low-side voltage of the signal generation circuit is -Y×AVDD, where M is the voltage amplification factor of the second boost circuit, Y is the voltage reduction factor of the buck circuit, and AVDD is the output voltage of the power supply; the maximum voltage value of the drive signal is M×AVDD, and the minimum voltage value of the drive signal is -Y×AVDD; the voltage of the excitation signal is (M+Y)×N×AVDD, where N is the voltage amplification factor of the first boost circuit.

10. A driver chip, characterized in that, It includes a signal generation circuit; the signal generation circuit is used to output a drive signal according to a first control signal output by a first control circuit; the drive signal is used to drive a first boost circuit to output an excitation signal, the voltage of the excitation signal is higher than that of the drive signal, and is used to excite the ultrasonic transducer to emit ultrasonic waves; The first control circuit includes a first timing circuit and a plurality of first driving circuits connected to the first timing circuit. The first timing circuit is used to output a plurality of first timing signals. The first driving circuit is used to amplify the first timing signals output by the first timing circuit to obtain a first control signal. The first control signals output by the plurality of first driving circuits are used to jointly drive the signal generation circuit. The first control signals output by the plurality of first driving circuits do not overlap. The signal generation circuit is used to output a driving signal according to the first control signals output by the plurality of first driving circuits. The driver chip further includes a second boost circuit; the second boost circuit is used to boost the high-side voltage of the signal generation circuit; the signal generation circuit is used to output a drive signal with increased voltage swing based on the boosted high-side voltage; the voltage swing is the difference between the maximum and minimum voltage values ​​of the drive signal.

11. A driver chip, characterized in that, It includes a signal generation circuit; the signal generation circuit is used to output a drive signal according to a first control signal output by a first control circuit; the drive signal is used to drive a first boost circuit to output an excitation signal, the voltage of the excitation signal is higher than that of the drive signal, and is used to excite the ultrasonic transducer to emit ultrasonic waves; The first control circuit includes a first timing circuit and a plurality of first driving circuits connected to the first timing circuit. The first timing circuit is used to output a plurality of first timing signals. The first driving circuit is used to amplify the first timing signals output by the first timing circuit to obtain a first control signal. The first control signals output by the plurality of first driving circuits are used to jointly drive the signal generation circuit. The first control signals output by the plurality of first driving circuits do not overlap. The signal generation circuit is used to output a driving signal according to the first control signals output by the plurality of first driving circuits. The driver chip also includes a step-down circuit; the step-down circuit is used to step down the low-end voltage of the signal generation circuit; the signal generation circuit is used to output a drive signal with increased voltage swing based on the stepped-down low-end voltage; the voltage swing is the difference between the maximum and minimum voltage values ​​of the drive signal.

12. A driver chip, characterized in that, It includes a signal generation circuit; the signal generation circuit is used to output a drive signal according to a first control signal output by a first control circuit; the drive signal is used to drive a first boost circuit to output an excitation signal, the voltage of the excitation signal is higher than that of the drive signal, and is used to excite the ultrasonic transducer to emit ultrasonic waves; The first control circuit includes a first timing circuit and a plurality of first driving circuits connected to the first timing circuit. The first timing circuit is used to output a plurality of first timing signals. The first driving circuit is used to amplify the first timing signals output by the first timing circuit to obtain a first control signal. The first control signals output by the plurality of first driving circuits are used to jointly drive the signal generation circuit. The first control signals output by the plurality of first driving circuits do not overlap. The signal generation circuit is used to output a driving signal according to the first control signals output by the plurality of first driving circuits. The driver chip further includes a second boost circuit and a buck circuit; the second boost circuit is used to boost the high-side voltage of the signal generation circuit; the buck circuit is used to buck the low-side voltage of the signal generation circuit; the signal generation circuit is used to output a drive signal with increased voltage swing based on the boosted high-side voltage and the bucked low-side voltage; the voltage swing is the difference between the maximum and minimum voltage values ​​of the drive signal.

13. An ultrasonic module, characterized in that, It includes an ultrasonic transmitting chip, a driving chip as described in claim 10, 11 or 12, and a first boost circuit; the ultrasonic transmitting chip includes a first control circuit and an ultrasonic transducer.

14. An ultrasonic transmitting chip, characterized in that, It includes an ultrasonic transmitting circuit and an ultrasonic transducer according to any one of claims 1-9.

15. An ultrasonic module, characterized in that, It includes the ultrasonic transmitting chip and the first boost circuit as described in claim 14.

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