Controlling device for an ultrasonic transducer and method for operating an ultrasonic transducer

Abstract

A controlling device (1) for an ultrasonic transducer (100) comprises and actuating element (2) and a feedback element (3). The actuating element (2) is configured to apply a burst signal (11) to the transducer (100) for generating and sending an ultrasonic signal (105). The actuating element (2) is further configured to apply a damping signal (12) to the transducer (100) for damping a periodic membrane displacement (4) after sending the ultrasonic signal (105). The feedback element (3) is configured to generate the damping signal (12) by determining peak point positions (41) of a membrane displacement (4) after termination of exciting the membrane. The feedback element (3) is further configured to generate the damping signal (12) comprising a sequence of pulses such that each pulse is centered around one peak point position (41). Furthermore, an ultrasonic transducer (100), a method for operating an ultrasonic transducer (100), a method for using an ultrasonic transducer (100), an electronic component, a computer-implemented method for operating a controlling device, a data processing device, a computer program, and a computer-readable storage media are specified.

Description

[0001] P2024 , 1072 WO N November 6 , 2025

[0002] Speci fication

[0003] Controlling device for an ultrasonic transducer and method for operating an ultrasonic transducer

[0004] The disclosure relates to a controlling device for an ultrasonic transducer and a method for operating such an ultrasonic transducer . Furthermore , the present disclosure relates to an ultrasonic transducer, a method for using an ultrasonic transducer, an electronic component , a computer- implemented method for operating a controlling device , a data processing device , a computer program, and a computer- readable storage media .

[0005] Piezoelectric ultrasonic transducers are commonly used for both sending and receiving ultrasonic signals . Such ultrasonic transducers may be used as distance sensors , for example for automotive vehicles . However, such ultrasonic transducers typically keep sending ultrasound even after excitation of ultrasound signals is terminated . The reason for this is in particular an ongoing membrane movement , also known as ringing . In general , ringing hinders a detection of a reflected ultrasonic signal by the transducer, since a ringing movement of the membrane overlaps a membrane displacement caused by an incoming ultrasonic signal .

[0006] Documents US 4 , 580 , 251 A, US 6 , 731 , 569 B2 , GB 2593477 A, JP 2022-73087 A, DE 102010039071 Al as well as Liu et al . „Reducing ring-down time of pMUTs with phase shi ft of driving Waveform" . Sensors and Actuators A 281 ( 2018 ) 100 - 107 , describe ultrasonic transducers and methods for operating the same . P2024 , 1072 WO N November 6 , 2025

[0007] 2

[0008] A problem to be solved, inter alia, is to speci fy a controlling device allowing for an improved ultrasonic transducer, in particular allowing for an improved distance measurement . Another problem to be solved, inter alia, is to speci fy a method to operate such an improved ultrasonic transducer, in particular allowing for an improved distance measurement . Further problems to be solved are , inter alia, to speci fy an ultrasonic transducer comprising such a controlling device , a method for using such an ultrasonic transducer for a distance measurement , an electronic component comprising such a controlling device , a computer- implemented method for operating such a controlling device , a data processing device comprising means for carrying out the computer-implemented method, a computer program comprising instructions to allow a computer to carry out the computer- implemented method, and a computer-readable storage media for storing the computer program .

[0009] These problems are solved, inter alia, by a controlling device comprising the features of claim 1 and by a method comprising the features of claim 21 , respectively . Further problems are solved, inter alia, by an ultrasonic transducer comprising the features of claim 24 , a method comprising the features of claim 25 , an electronic component comprising the features of claim 26 , a computer-implemented method comprising the features of claim 28 , a device comprising the features of claim 29 , a computer program comprising the features of claim 30 , and storage media comprising the features of claim 31 , respectively .

[0010] In at least one embodiment of the controlling device for an ultrasonic transducer, the controlling device comprises an actuating element and a feedback element . P2024 , 1072 WO N November 6 , 2025

[0011] 3

[0012] The actuating element is configured to apply a burst signal to the transducer for generating and sending an ultrasonic signal . The actuating element is further configured to apply a damping signal to the transducer for damping a periodic membrane displacement after sending the ultrasonic signal .

[0013] The feedback element is configured to generate the damping signal by determining peak point positions of a membrane displacement after termination of exciting the membrane . The feedback element is further configured to generate the damping signal such that the damping signal comprises a sequence of pulses wherein each pulse is centered around one peak point position .

[0014] In particular, the actuating element is configured to actuate the transducer or a membrane of the transducer to generate and send an ultrasonic wave being the ultrasonic signal . This actuation excites an oscillation or a periodic membrane displacement . Thereby, the membrane is preferably in resonance and oscillates with a sending mode . Thus , the sending mode has in particular a relatively low dissipation, allowing an ef fective generation of the ultrasonic signal .

[0015] The burst signal for actuating the transducer to generate the ultrasonic signal is , for example , a sequence of pulses , preferably rectangular pulses . For example , the burst signal is applied to a piezoelectric element of the transducer, which is configured to generate mechanical motion from the electronic burst signal . In this case , the piezoelectric element may actuate the membrane . P2024 , 1072 WO N November 6 , 2025

[0016] 4

[0017] In particular, the damping signal is generated by determining peak point positions of a membrane displacement signal , which in particular is an electrical or electronic signal corresponding to the membrane displacement . The membrane displacement signal may also be referred to as a feedback signal . For example , the membrane displacement can be analyzed, processes and / or evaluated by software using the membrane displacement signal . In particular, by evaluating the membrane displacement signal , peak point positions of the membrane displacement can be obtained .

[0018] For example , raw data of the damping signal are generated by the feedback element . Form the raw data, the damping signal can be constructed . In particular, the raw data of the damping signal comprise all information of the damping signal . Thus , also in this case , the feedback element can generate the damping signal . For example , the feedback element is configured to generate the damping signal and store raw data of the damping signal for a subsequent reconstruction of the damping signal .

[0019] During operation of the transducer, the sent ultrasonic signal is reflected by an obj ect to which a distance is to be measured . The reflected ultrasonic signal is detected by the transducer, preferably by the membrane , which is excited to oscillate due to the incoming reflected ultrasonic signal .

[0020] The transducer trans forms the mechanical membrane movement to an electronic signal , in particular, the membrane displacement signal , which may be processed, for example by a digital signal processor, to determine the distance to the ob ect . P2024 , 1072 WO N November 6 , 2025

[0021] 5

[0022] Since the reflected ultrasonic signal typically has a lower intensity than the sent ultrasonic signal , a membrane displacement excited by the reflected ultrasonic signal is relatively low . Thus , ringing has to be ef ficiently damped to make the membrane sensitive to the reflected ultrasonic signal .

[0023] To achieve this , the feedback element is configured to generate a damping signal . Preferably, the damping signal comprises a sequence of pulses , wherein each pulse comprises a width and is centered around a peak point position of the membrane displacement . This means in particular that during ringing the pulses of the damping signal are applied to the membrane i f the membrane displacement is at a peak point position, i . e . a local minimum or maximum . This allows for the damping signal to have a particularly ef fective influence on the membrane displacement , since the membrane has a comparably low velocity at the peak point positions , thus making the membrane sensitive to the pulses of the damping signal . Thereby, it is possible that the transducer can be used for distance measurements , where the obj ect to be measured is relatively close to the transducer . For example , the transducer can ef ficiently detect obj ects that are at a distance below 10 cm or below 5 cm or below 4 cm .

[0024] A matching of the pulses of the damping signal , in the following also referred to as damping pulses , to the peak point positions is in particular achieved by the feedback element , which is configured to determine the peak point positions of the membrane displacement , in particular via the membrane displacement signal . Preferably, the peak point positions are time stamps . This means in particular that the feedback element calculates and determines a chronological P2024 , 1072 WO N November 6 , 2025

[0025] 6 sequence of the damping pulses as the damping signal so that the feedback element determines at which point in time a damping pulse is to be applied to the transducer or the membrane of the transducer .

[0026] The controlling device described herein is advantageously configured to generate a damping signal by using information, i . e . the peak point positions of the ringing, provided by means of the feedback element . Thus , the damping signal can be generated comparably easy . For example , only a few electronic devices such as a processor, comparators , buf fers and timers may be suf ficient to determine the peak point positions and generate the damping signal thereof . Hence , the controlling device herein has only relatively small hardware requirements .

[0027] Furthermore , the controlling device and its functions may be at least partially implemented on an application speci fic integrated circuit (AS IC ) , a microcontroller, a field programmable gate array ( FPGA) or the like , optionally using analog-to-digital converters for signal processing . Moreover, the controlling device and its functions may at least be partially implemented on a computer with suitable hardware for signal generation acquisition . Hence , the controlling device and the transducer can be manufactured at low costs . In particular, at least some steps of a controlling method carried out by the controlling device can be computer- implemented as software that is executable on these devices .

[0028] Moreover, generating the damping signal advantageously does not require performing an optimi zation process or the like , but can easily be generated from peak point positions of the membrane displacement , for example via the membrane P2024 , 1072 WO N November 6 , 2025

[0029] 7 displacement signal . Thus , the damping signal can be obtained in a particularly short period of time . It is possible that one ringing event is suf ficient to detect the peak point positions and generate the damping signal thereof .

[0030] In particular, the damping signal is independent of the sending mode and / or a resonance of the membrane or the transducer . Preferably, the timing of damping signal is purely obtained by considering the peak point positions . Furthermore , for shaping the pulses , i . e . determining widths of the pulses of the damping signal , the amplitude of the membrane displacement or the membrane displacement can be taken into account . That is in particular, even i f the peak point positions do not align with the resonance frequency or the sending mode , the controlling device is advantageously capable of generating a damping signal which may be custom- tuned to the peak point positions .

[0031] It is possible that for each interval between two zerocrossing points of the periodic membrane displacement , which may be used to determine the peak point positions as described below and / or between two peak point positions , the damping signal may be adaptively shaped with respect to width of the pulses , start timing point of the pulses and / or ending timing point of the pulses of the damping signal , for example . A period between the start timing and the end timing of a certain pulse corresponds to the width of said certain pulse , i f the pulse is a rectangular pulse .

[0032] The controlling device described herein advantageously allows to adapt the damping signal during ringing of the membrane so that changes in the ringing movement of the membrane can be adapted, and the damping signal can be adj usted accordingly . P2024 , 1072 WO N November 6 , 2025

[0033] 8

[0034] In particular in contrast to approaches , where the damping signal is based on a pulse train having a fixed frequency such as a resonance frequency of the membrane or the transducer, better adaption to the actual ringing oscillation of the membrane can be achieved .

[0035] It is in particular furthermore possible that due to electronic delays and various unknown factors , the membrane displacement following excitation does not adhere to a speci fic constant frequency or resonance frequency, which was observed in experiments . This means that by detecting the zero-crossing points , it is possible to generate the damping signal with an adj ustable , non-constant frequency to ef ficiently reduce membrane vibrations after excitation .

[0036] Consequently, the damping signal can be adapted easily and fast to changing environmental conditions and other factors . For example , a change in temperature , ambient pressure or humidity may change the resonance frequency of the transducer and thus the sending mode . As a result , the damping signal may have to be adapted to the new environmental conditions so that ringing can ef ficiently be suppressed . Due to small convergence time of the controlling device described herein, an adapted damping signal can be generated particularly fast , making the transducer suitable for applications with changing environmental conditions such as a distance sensor for automotive vehicles . Furthermore , environmental noise can be taken into account .

[0037] For example , adaption of the damping signal can be carries out by a closed-loop feedback procedure , where the adaption is carried out automatically in a closed feedback loop . In this case , the feedback element preferably is configured to P2024 , 1072 WO N November 6 , 2025

[0038] 9 automatically adapt the damping signal i f a change in a swinging characteristic due to , for example , a change in environmental conditions is detected . Alternatively, an openloop adaption of the damping signal is also possible .

[0039] Further, the controlling device and methods carried out by the controlling device described herein can be used for existing transducers with minimal adaptions , since expensive modeling and calibration can be omitted .

[0040] According to at least one embodiment of the controlling device , the feedback element is further configured to monitor at least one swinging characteristic of the membrane of the transducer during operation . For example , the swinging characteristic is monitored after the ultrasonic signal is sent . This means in particular that the swinging characteristic is monitored when the damping signal is applied and / or during ringing of the membrane .

[0041] The feedback element is further configured to generate an adapted damping signal i f the swinging characteristic changes above a predetermined threshold . Such a change in the swinging characteristic can in particular occur i f environmental conditions of the transducer, such as temperature , pressure or the like , change .

[0042] For example , the swinging characteristic is an envelope function of the periodic membrane displacement which may be indicative by a measurable electric signal . The envelope function corresponds to an amplitude of the measurable electric signal corresponding to the membrane displacement , i . e . the membrane displacement signal . The envelope function is generated, for example , by digiti zing raw data of the P2024 , 1072 WO N November 6 , 2025

[0043] 10 membrane displacement , i . e . the amplitude , and applying one or more digital filters . The envelope function in particular corresponds to an energy stored in a mode of the ringing membrane .

[0044] During intended operation of the transducer, a distance measurement can be carried out using the envelope function . For example , the envelope function of the transducer without an obj ect to be detected is obtained as a baseline for calibration . I f subsequently an obj ect is arranged in a measurement region of the transducer, the envelope function may slightly deviate from the baseline , indicating that the periodic membrane displacement has changed due to the reflected ultrasonic signal of the obj ect . Preferably, determining the distance to the obj ect from the deviation in the envelope functions is carried out by a digital signal processor .

[0045] In particular, the threshold is a means to distinguish whether the change in the envelope function arises due to a change in environmental conditions or due to an obj ect in the measurement region .

[0046] Preferably, the swinging characteristic such as the envelope function is monitored in a certain monitoring range . The monitoring range , for example , corresponds to a subregion of the measurement region corresponding to small distances to the transducer, for example below 5 cm . This monitoring period in particular corresponds to a free ringing period of the membrane . The free ringing period of the membrane here and in the following is a period of time during which ringing of the membrane occurs , but no damping signal is applied . P2024 , 1072 WO N November 6 , 2025

[0047] 11

[0048] Preferable , i f the envelope function changes in the monitoring range and the change is above the threshold, the adapted damping signal is generated by the feedback element .

[0049] It is possible that the adapted damping signal is generated once the threshold is exceeded . It is also possible to perform an average of several exceedances of the threshold over several ringing periods .

[0050] Preferably, the feedback element is configured to generate the adapted damping signal between the application of two subsequent burst signals to the transducer . In other words , the adapted damping signal is generated in one measurement cycle of the transducer, also referred to as a frame .

[0051] In particular, one frame represents the period of time between actuating the transducer to send the ultrasonic signal and receiving the reflected ultrasonic signal . In particular, during one frame , the burst signal is applied to the transducer during an excitation period, the damping signal is applied during a damping period . In other words , a frame represents a period of time comprising the excitation period, the damping period and the free ringing period . For example , during operation of the transducer 15 frames per second can be carried out .

[0052] According to at least one embodiment , the actuating element is configured to provide the burst signal and the damping signal in a common pulse sequence . This means in particular that the damping signal directly follows the burst signal .

[0053] According to at least one embodiment , the feedback element is configured to generate and adj ust the damping signal P2024 , 1072 WO N November 6 , 2025

[0054] 12 independently of a resonance of the membrane displacement . In particular, the feedback element is configured to generate or adapt the timing of the damping signal purely on the basis of the peak point positions . Furthermore , for forming the pulses , i . e . determining widths of the pulses of the damping signal , the amplitude of the membrane displacement or the membrane displacement can be taken into account . That is in particular, even i f the peak point positions do not align with the resonance frequency or the sending mode , the controlling device is advantageously capable of generating a damping signal which may be custom-tuned to the peak point positions .

[0055] According to at least one embodiment , the actuating element is configured to provide at least the damping signal in at least one positive state , at least one negative state and at least one neutral state . For example , the damping signal in a positive state corresponds to a positive voltage value of the electric damping signal . For example , the damping signal in a negative state corresponds to a negative voltage value of the electric damping signal . For example , the damping signal in the neutral state corresponds to a voltage value of the electric damping signal that is essentially zero . The neutral state is in particular generated by applying a high impedance to an output of the actuating element such that essentially the complete voltage drops at the impedance .

[0056] In particular, the actuating element is configured to apply a pulse of the damping signal in the positive state i f the corresponding peak point of the membrane displacement or the membrane displacement signal is a local minimum . At the local minimum, the membrane displacement or the membrane displacement signal in particular has a negative amplitude P2024 , 1072 WO N November 6 , 2025

[0057] 13 with respect to a baseline of the membrane displacement or the membrane displacement signal , where the membrane is at rest .

[0058] In particular, the actuating element is configured to apply a pulse of the damping signal in the negative state i f the corresponding peak point of the membrane displacement or the membrane displacement signal is a local maximum . At the local maximum, the membrane displacement or the membrane displacement signal in particular has a positive amplitude with respect to the baseline of the membrane displacement or the membrane displacement signal .

[0059] In particular, the actuating element is configured to apply the damping signal in the neutral state i f the membrane displacement or the membrane displacement signal has a zerocrossing point . At the zero-crossing point position, the amplitude of the membrane displacement or the membrane displacement signal in particular is essentially zero with respect to the baseline of the membrane displacement or the membrane displacement signal .

[0060] Preferably, the damping signal has a 180 ° phase shi ft with respect to the periodic membrane displacement or the membrane displacement signal . Additionally or alternatively, the damping signal has a 180 ° phase shi ft with respect to burst signal .

[0061] Advantageously, the membrane displacement can ef ficiently be damped i f the damping signal comprises counter pulses counteracting the membrane displacement at the peak point positions . P2024 , 1072 WO N November 6 , 2025

[0062] 14

[0063] According to at least one embodiment , the controlling device comprises a timer configured to provide a clock signal , in particular based on the electronic signal from the membrane displacement . The peak point positions are determined by means of the clock signal .

[0064] Preferably, a time resolution of the timer is at least ten times higher than an operation frequency of the ultrasonic transducer . For example , the operation frequency of the ultrasonic transducer is between 50 kHz and 100 kHz , for example 80 kHz . In this case , the time resolution is , for example , 1 ms- l .

[0065] The timer and the clock signal in particular provide a time resolution of the controlling device and / or methods or computer-implemented methods or algorithms , such as a control algorithm, carried out by the controlling device . For example , the timer may also comprise a counter . For example , for processing and / or storing the peak point positions , time stamps generated by means of the timer are assigned to the peak point positions and optionally stored . This allows advantageously to assign speci fic pulses of the damping signal to speci fic peak point positions of the membrane displacement .

[0066] According to at least one embodiment , the actuating element comprises a first buf fer configured to store raw data of the burst signal and the damping signal . For example , in the first buf fer time stamps for pulses of the burst signal and / or damping signal are stored . By means of the time stamps and the clock signal , a chronological sequence of pulses giving the burst signal and / or the damping signal can be generated . P2024 , 1072 WO N November 6 , 2025

[0067] 15

[0068] Preferably, the actuating element comprises a signal generator that is configured to generate the burst signal and / or the damping signal as a chronological sequence of pulses by means of the raw data and the clock signal .

[0069] According to at least one embodiment , the feedback element is configured to determine peak point positions of the membrane displacement by detecting zero-crossing point positions of the membrane displacement and calculating a median between two adj acent zero-crossing point positions . In particular, the feedback element is configured to determine peak point positions of the membrane displacement by detection zerocrossing point positions of the membrane displacement by detecting zero-crossing point positions of an electrical or electronic signal induced by and corresponding to the membrane displacement , i . e . the membrane displacement signal .

[0070] For example , the zero-crossing point positions are determined by means of a comparator and the clock signal . For example , the comparator compares the membrane displacement signal , corresponding to the membrane displacement with zero . In particular, each time the membrane displacement signal is detected to be zero by the comparator, a time stamp, provided by the clock signal , is assigned to define the zero-crossing point position of the membrane displacement . The membrane displacement signal is , for example , an electrical signal generated from the piezoelectric element based on the mechanical membrane displacement .

[0071] For example , i f a first zero-crossing point position is detected at a time of 10 arbitrary time units and a second zero-crossing point position is detected at a time of 20 P2024, 1072 WO N November 6, 2025

[0072] 16 arbitrary time units, the associated peak point position is approximately at a time of 15 arbitrary time units.

[0073] By using a comparator to determine zero-crossing point positions and calculating the peak point positions from the zero-crossing point positions, the peak point positions can be easily determined.

[0074] According to at least one embodiment of the controlling device, the feedback element is configured to generate the damping signal to comprise pulses with a width lower than half of a period of the periodic membrane displacement.

[0075] For example, if the pulse is in a positive state, the width gives a duration during which the pulse is in the positive state. For example, considering that half a period of the membrane displacement comprises a local minimum and said period is a time period from two zero-crossing point positions adjacent to the local minimum, the associated pulse of the damping signal is in the positive state for a time period corresponding to the width of the pulse centered around the local minimum, i.e. the peak point position. At other times of said period, the damping signal is in the neutral state, i.e. essentially zero.

[0076] Furthermore, if, for example, a first zero-crossing point position is detected at a time of 10 arbitrary time units and a second zero-crossing point position is detected at a time of 20 arbitrary time units, the associated peak point position, i.e. the local minimum, is approximately at a time of 15 arbitrary time units. In this case, the width of the pulse that is particularly in the positive state is lower P2024 , 1072 WO N November 6 , 2025

[0077] 17 than 10 arbitrary time units since the hal f period of the membrane displacement is 10 arbitrary time units .

[0078] According to at least one embodiment , the feedback element is configured to adapt the damping signal in each interval between two adj acent zero-crossing points , in particular regarding widths of the pulses of the damping signal .

[0079] According to at least one embodiment , the feedback element is configured to generate or adj ust the widths of the pulses of the damping signal based on an amplitude of the periodic membrane displacement .

[0080] In particular, the widths of the pulses of the damping signal are generated or adj usted based on an amplitude of the membrane displacement signal , also referred to as feedback signal , corresponding to the membrane displacement , in particular when the membrane is ringing . For example , when the amplitude of the membrane displacement is low, the width of the pulses may be reduced, and when the amplitude of the membrane displacement is high, the width of the pulses may be increased . Thus , the feedback element is in particular configured to carry out an adaptive control of the widths of the damping pulses based on the amplitude of the membrane displacement .

[0081] Preferably, the controlling device , in particular the feedback element , is configured for adaptive adj usting, generating and shaping of the damping signal , i . e . , the damping pulses , for example with respect to width, start timing, end timing, within each zero-crossing interval based on real-time amplitude of the membrane displacement . A zerocrossing interval is in particular a period between two zero- P2024, 1072 WO N November 6, 2025

[0082] 18 crossing points. This period may correspond to a period between two peak point positions. The zero-crossing points may be used to determine the peak point positions as described in numerous embodiments disclosed herein. The start timing and the end timing are in particular time stamps that are preferably provided by the timer. A period between the start timing and the end timing of a certain pulse corresponds to the width of said certain pulse.

[0083] Advantageously, such an adaptive control allows for an efficient damping, which is in particular tailored to actual vibration and oscillation of the membrane, thus enhancing overall performance and energy efficiency.

[0084] For example, the widths of the damping signal may be adaptively adjusted based on a factor of the absolute maximum or minimum value of the membrane displacement in each time period, i.e. frame.

[0085] It is possible that all pulses of the damping signal comprise the same width. However, it is also possible that different pulses of the damping signal differ another in width.

[0086] It is possible, for example, that at least one or each pulse comprises a width different from all widths of the other pulses of the damping signal. It is also possible that the damping signal comprises groups of pulses, each comprising at least two pulses, wherein within each group all pulses comprise the same width and the widths of different groups differ from another.

[0087] By adjusting the pulse widths of the damping signal, it is advantageously possible to effectively damp ringing of the P2024 , 1072 WO N November 6 , 2025

[0088] 19 membrane . In particular, it is possible to excite a damping mode for ef ficient energy dissipation by adapting the widths of the pulses of the damping signal accordingly .

[0089] According to at least one embodiment , the feedback element comprises an edge capture unit configured to determine an edge orientation of the periodic membrane displacement at a zero-crossing point position . In particular, a state of the damping signal is adj usted according to the edge orientation .

[0090] For example , at a certain zero-crossing point position the edge of the membrane displacement signal corresponding to the membrane displacement is negative , i . e . has a negative gradient . In this case the peak point position chronologically before the zero-crossing point position is a local maximum and the peak point position chronologically subsequent to the zero-crossing point position is a local minimum . Based on this information, the feedback element is in particular configured to generate the damping signal such that the damping signal has a pulse in the negative state at the position of the preceding peak point position and has a pulse in the positive state at the position of the subsequent peak point position, viewed with respect to the certain zerocrossing point position .

[0091] For example , at another certain zero-crossing point position the edge of the membrane displacement signal corresponding to the membrane displacement is positive , i . e . has a positive gradient . In this case the peak point position chronologically before the zero-crossing point position is a local minimum and the peak point position chronologically subsequent to the zero-crossing point position is a local maximum . Based on this information, the feedback element is P2024 , 1072 WO N November 6 , 2025

[0092] 20 in particular configured to generate the damping signal such that the damping signal has a pulse in the positive state at the position of the preceding peak point position and has a pulse in the negative state at the position of the subsequent peak point position, viewed with respect to the certain zerocrossing point position .

[0093] According to at least one embodiment , the feedback element comprises a second buf fer configured to store peak positions and the edge orientation . It is also possible that the zerocrossing point positions are stored in the second buf fer such that the peak point positions can be calculated from the zero-crossing point positions as described above . In particular, the peak point positions and / or zero-crossing point positions are stored as time stamps determined by means of the clock signal . For example , in the second buf fer the peak point position and / or the zero-crossing point position and the associated edge orientation are stored as a pair of values . These data may be raw data of the damping signal , from which the damping signal may be constructed .

[0094] It is also possible that pulse widths are stored in the second buf fer . In this case the peak point position and / or the zero-crossing point position, the associated edge orientation and the associated pulse widths may be stored as a triplet of values in the second buf fer .

[0095] Furthermore , the feedback element comprises a calculation unit configured to determine the damping signal based on data stored in the second buf fer . Preferably, the calculation unit is connected to the first buf fer and is configured to store the generated damping signal in the first buf fer such that P2024 , 1072 WO N November 6 , 2025

[0096] 21 the actuating unit can apply the damping signal to the transducer .

[0097] It is possible that the second buf fer and the calculation unit are implemented in one component .

[0098] According to at least one embodiment , the actuating element is configured to apply and / or the feedback element is configured to generate the damping signal comprising a first part and a second part . The first part comprises pulses of a first kind and the second part comprises pulses of a second kind . In particular, pulses of the second kind have a smaller width than pulses of the first kind . Preferably, the second part applied subsequent to the first part . The width of the pulses of the second kind may be adj usted adaptively based on a factor of the absolute maximum or minimum value of the membrane displacement .

[0099] For example , the first part is a fixed part of the damping signal . In this case , the first part is not adapted i f the damping signal is adapted after a threshold-exceeding change in the swinging characteristic is observed .

[0100] The second part is in this case preferably a variable part of the damping signal , which may be adapted after a thresholdexceeding change in the swinging characteristic is observed . Additionally or alternatively, the second part may be adapted according to an amplitude of the membrane displacement . In particular, a width of the pulses of the second kind may be adapted based on the amplitude of the membrane displacement . By adapting only a part of the damping signal , i . e . the second part , adaption can be carried out particularly fast . P2024 , 1072 WO N November 6 , 2025

[0101] 22

[0102] It is possible that the first part and the second part comprise a same amplitude . It is also possible that the first and / or second part comprise the same amplitude as the burst signal .

[0103] For example , pulses of the first part of the damping signal each comprise a width that corresponds to hal f a period of the periodic membrane displacement . In this case the first part can correspond to the burst signal with a phase shi ft of 180 ° . This advantageously allows an ef fective dissipation of energy from the sending mode . In this case , the second part is preferably configured to excite a damping mode di f ferent from the sending mode as described in the following . By applying the first part before the second part , exciting the damping mode can be facilitated .

[0104] According to at least one embodiment , the feedback element is configured to adapt the second part based on an amplitude of the membrane displacement , i . e . , the membrane displacement signal . In particular, the second part is adapted in accordance with the amplitude of membrane displacement as described above . The first part is preferably a fixed part unadapted by the feedback element , in particular during ringing . That is , the feedback element is in particular configured to only adapt the first part during one measurement cycle or frame . Advantageously, adapting the damping signal can be carried out particularly fast i f only the second part is adapted by the feedback element .

[0105] According to at least one embodiment , the pulses of the damping signal may vary in position, width, shape , energy, phase and modulation . This means in particular, the actuating element is configured to apply and / or the feedback element is P2024 , 1072 WO N November 6 , 2025

[0106] - 23 - configured to generate the damping signal such that the pulses of the damping signal may vary in position, width, shape , energy, phase and modulation . In particular, the pulses of the second kind may vary in at least one of the above-mentioned parameters .

[0107] According to at least one embodiment , the controlling device is configured to excite a damping mode by applying the damping signal having a higher energy dissipation than the sending mode excited by applying the burst signal . The damping mode and / or the sending mode are preferably stable modes or Eigenmodes of the transducer or the membrane of the transducer or an oscillating system of the transducer formed by the membrane together with a housing of the transducer .

[0108] In particular, the oscillating system and further preferably the housing of the transducer is adapted such that the sending mode and the damping mode are stable .

[0109] Preferably, i f the membrane oscillates in the sending mode , the membrane is excited in a central region, in particular exclusively in the center region . It is possible that the membrane may be at rest in at least one boundary region that borders the housing of the transducer when oscillating in sending mode . Thus , energy dissipation can be kept comparably low during oscillation in sending mode .

[0110] Further preferably, i f the membrane oscillates in the damping mode , the membrane is also excited in boundary regions of the membrane surrounding the central region . In plan view of the membrane , the boundary regions may be an annular or frame area surrounding the central region . In particular, the P2024 , 1072 WO N November 6 , 2025

[0111] 24 boundary regions are in contact with the housing, which advantageously allows for high energy dissipation .

[0112] Furthermore , a method for operating an ultrasonic transducer is speci fied . The transducer in particular comprises a controlling device described herein in accordance with one or more of the above discussed embodiments . Thus , all features disclosed for the controlling device are also disclosed for the method and vice versa .

[0113] According to at least one embodiment , the method for operating an ultrasonic transducer comprises a step of exciting a membrane of the transducer for generating and sending an ultrasonic signal by applying a burst signal to the membrane . In a subsequent step, the membrane is damped by applying a damping signal to the membrane . In particular, the damping signal is generated by determining peak point positions of a membrane displacement after termination of exciting the membrane , wherein the damping signal comprises a chronological sequence of pulses , wherein each pulse is centered around one peak point position . In particular, the damping signal is generated by determining peak point positions of a membrane displacement signal , which in particular is an electrical or electronic signal corresponding to the membrane displacement . For example , the membrane displacement can be analyzed, processes and / or evaluated by software using the membrane displacement signal .

[0114] For example , the damping signal directly follows the burst signal . For example , the burst signal and the damping signal are provided together as a sequence of pulses . P2024 , 1072 WO N November 6 , 2025

[0115] 25

[0116] According to at least one embodiment of the method, in a further step, a swinging characteristic of the membrane is monitored and the damping signal is adapted i f the swinging characteristic changes above a predetermined threshold .

[0117] For example , the swinging characteristic is an envelope function corresponding to an amplitude of the membrane displacement .

[0118] A change in the swinging characteristic may be caused by a change in environmental conditions of the environment of the transducer . Such environmental conditions may be temperature , ambient pressure or the like . Thus , the transducer can be used in applications with changing environmental conditions .

[0119] According to at least one embodiment of the method, the peak point positions of the membrane displacement are determined by detecting zero-crossing point positions of the membrane displacement , in particular the membrane displacement signal , and calculating a median between two adj acent zero-crossing point positions .

[0120] Furthermore , an ultrasonic transducer is speci fied . The transducer in particular comprises at least one controlling device described herein in accordance with one or more embodiments discussed above . Therefore , all features disclosed for the controlling device are also disclosed for the transducer and vice versa .

[0121] In particular, during operation of a transducer comprising a controlling device described herein, an ef ficient damping of a membrane ringing is possible . Thus , the ultrasonic transducer can be used for distance measurements , where a P2024 , 1072 WO N November 6 , 2025

[0122] 26 distance to the obj ect is below 10 cm, preferably below 5 cm or even below 4 cm .

[0123] Furthermore , a measurement arrangement for measuring a distance to an obj ect is speci fied . The measuring arrangement in particular comprises a transducer described herein in accordance with one or more embodiments discussed above . Therefore , all features disclosed for the transducer are also disclosed for the measuring arrangement and vice versa .

[0124] Preferably, the measuring arrangement comprises exactly one ultrasonic transducer comprising a controlling device described herein . This means that measuring the obj ect can be carried out using exactly one transducer to send the ultrasonic signal and to receive the reflected ultrasonic signal .

[0125] Furthermore , a method for using an ultrasonic transducer and / or a measurement arrangement for a distance measurement is speci fied . The method for using an ultrasonic transducer and / or a measurement arrangement in particular uses a transducer and / or a measurement arrangement described herein in accordance with one or more embodiments discussed above . Therefore , all features disclosed for the transducer and / or the measurement arrangement are also disclosed for the method for using of an ultrasonic transducer and / or a measurement arrangement and vice versa .

[0126] In particular, a distance from the transducer to the obj ect to be measured is between 3 cm and 2 m, inclusive . For example , the distance is smaller than 10 cm or smaller than 6 cm or smaller than 5 cm . P2024 , 1072 WO N November 6 , 2025

[0127] 27

[0128] Furthermore , an electronic component is speci fied . The electronic component in particular comprises at least one controlling device described herein according to one or more of the embodiments described above . Therefore , all features disclosed for the controlling device are also disclosed for the electronic component and vice versa .

[0129] The controlling device is preferably part of an electronic component . For example , the electronic component comprises or is a microcontroller, an application speci fic integrated circuit (AS IC ) or a field programmable gate array ( FPGA) or a computer having means configured for signal generation and acquisition .

[0130] For example , the controlling device comprises the actuating element , the feedback element and the timer . A driver for generating an electronic signal from the damping signal and the burst signal and the comparator may be individual elements of the electronic component . It is also possible that the driver and / or the comparator are part of the controlling device .

[0131] The electronic component may further comprise an analog-to- digital converter, ADC, and at least one filter unit . By the ADC and the filter unit , the electrical signal provided by the piezoelectric element corresponding to the membrane displacement can be digiti zed and processed for evaluation, for example to carry out a distance measurement . This evaluation can be carried out by a digital signal processor, which may be part of the electronic component or may be a separate further electronic component . P2024 , 1072 WO N November 6 , 2025

[0132] 28

[0133] The electronic component is preferably part of the transducer and is configured to drive and control the transducer . Optionally, the electronic component can evaluate measurement results of the transducer .

[0134] Preferably, it is possible to use the electronic component for various transducer and applications . Thus , the controlling device and the electronic component described herein are advantageously suitable for various transducers , wherein small to essentially no adaptions to these transducers are required .

[0135] Furthermore , a computer-implemented method for operating a controlling device is speci fied . In particular, the method is configured to operate a controlling device described herein in accordance with one or more embodiments described above . That is , all features disclosed for the controlling device are also disclosed for the computer-implemented method and vice versa .

[0136] According to at least one embodiment , the computer- implemented method comprises a step of providing the burst signal and the damping signal by reading raw data of the burst signal and the damping signal stored in the first buf fer and generating the burst signal and the damping signal to be provided . For example , the burst signal and the damping signal are generated by the signal generator .

[0137] In a further step of the computer-implemented method the raw data of the damping signal are generated by determining peak point positions of a membrane displacement signal . The membrane displacement signal in particular corresponds to the membrane displacement . P2024 , 1072 WO N November 6 , 2025

[0138] - 29 -

[0139] In particular, at least some of the steps carried out by at least some of the controlling unit , in particular the first buf fer, the signal generator, the comparator, the edge capture unit , the calculation unit , the second buf fer and a threshold unit , for example described above in connection with one or more embodiments of the controlling unit , the electronic component or the method for operating a transducer, are executable by the computer-implemented method . Thus , all respective features of these elements disclosed above , are preferably also disclosed for the computer-implemented method .

[0140] In particular, the computer-implemented method comprises a closed-loop control algorithm . Alternatively, the method may comprise a fixed sequence as an open-loop control .

[0141] In case of a closed-loop control algorithm the method comprises a step of adapting the damping signal , for example i f a change in a swinging characteristic above a threshold is detected as described above . For example , the change in the swinging characteristic is a result of a change in environmental conditions . The change in the swinging characteristic above a threshold is in particular detected by the threshold unit . Such an adaptive closed-loop control approach has the advantage of adaptation to any context and gives an advantageous control method to reduce the ringdown ef fect of ultrasonic transducers and a method for operating such an ultrasonic transducer in order to enhance the accuracy of distance measurement by reducing the minimum measurable distance . P2024 , 1072 WO N November 6 , 2025

[0142] 30

[0143] Furthermore , a data processing device comprising means for carrying out the computer-implemented method is described . The computer-implemented method can be carried out on the data processing device . Therefore , all features disclosed for the computer-implemented method are also disclosed for the data processing device and vice versa .

[0144] The data processing device may be a processor for a computer . The computer may further comprise suitable means , for example hardware , for signal generation and acquisition . Alternatively, the data processing device may be part of or may be a microcontroller, an application speci fic integrated circuit (AS IC ) , a field programmable gate array ( FPGA) . For example , the data processing device may a part of may be the electronic device or the controlling device .

[0145] Furthermore , a computer program is speci fied . In particular, the computer program comprises instructions which, when the program is executed by a computer, cause the computer to carry out the computer-implemented method disclosed above . Therefore , all features disclosed for the computer- implemented method are also disclosed for the computer program and vice versa . For example , the data processing device is part of the computer . The computer may comprise or be a microcontroller, an application speci fic integrated circuit (AS IC ) or a field programmable gate array ( FPGA) and / or preferably comprises means configured for signal generation and acquisition .

[0146] Furthermore , a computer-readable storage media is speci fied . In particular, the computer-readable storage media having stored thereon the computer program described above . Therefore , all features disclosed for the computer- P2024 , 1072 WO N November 6 , 2025

[0147] 31 implemented method and the computer program are also disclosed for the c computer-readable storage media and vice versa .

[0148] Further advantages and advantageous embodiments and further developments of the controlling device , the transudcer, the measurement arrangement , the method for operating a transducer, and the method for using an ultrasonic transducer described herein will become apparent from the following exemplary embodiments shown in connection with schematic drawings . Identical elements , elements of the same kind or elements having the same ef fect are provided with the same reference signs in the figures . The figures and the proportions of the elements shown in the figures are not to be regarded as true to scale . Rather, individual elements may be shown exaggeratedly large for better representability and / or for better comprehensibility .

[0149] In the figures :

[0150] Figure 1 shows a schematical illustration of an ultrasonic transducer described herein according to an exemplary embodiment ;

[0151] Figure 2 shows a block diagram illustrating a controlling device for an ultrasonic transducer described herein according to a first exemplary embodiment ;

[0152] Figure 3 illustrates a change in oscillation modes of a membrane of the transducer according to the exemplary embodiment caused by a damping signal ; P2024 , 1072 WO N November 6 , 2025

[0153] 32

[0154] Figure 4 shows a block diagram illustrating a controlling device for an ultrasonic transducer described herein according to a second exemplary embodiment ;

[0155] Figure 5 shows a raw signal of an electronic signal corresponding to an amplitude of a membrane displacement as a function of time according to a first example ;

[0156] Figure 6 shows a burst signal and damping signal exciting the membrane displacement illustrated in Figure 5 ;

[0157] Figure 7 illustrates an envelope function generated from the membrane displacement illustrated in Figure 5 ;

[0158] Figure 8 shows a raw signal of an electronic signal corresponding to an amplitude of a membrane displacement as a function of time according to a second example ;

[0159] Figure 9 illustrates an envelope function generated from the membrane displacement illustrated in Figure 8 ;

[0160] Figure 10 shows a raw signal of an electronic signal corresponding to an amplitude of a membrane displacement as a function of time according to a third example ;

[0161] Figure 11 illustrates an envelope function generated from the membrane displacement illustrated in Figure 10 ; P2024 , 1072 WO N November 6 , 2025

[0162] 33

[0163] Figure 12 illustrates a closed-loop algorithm that is executable on a controlling device 1 described herein .

[0164] The ultrasonic transducer 100 according to the exemplary embodiment shown in Figure 1 comprises a housing 103 . At a bottom surface of the housing a membrane 104 is arranged . The transducer 100 further comprises a piezoelectric element 102 configured to convert at least one electrical signal into mechanical movement to excite the membrane 104 .

[0165] The transducer 100 further comprises a controlling device 1 providing a burst signal 11 to excite an oscillation or periodic membrane displacement 4 in the membrane 104 . As a result , the transducer 100 emits an ultrasonic signal 105 .

[0166] The transducer 100 is , for example , configured to measure a distance to an obj ect . At the obj ect the ultrasonic signal 105 is reflected . The reflected ultrasonic signal can be detected by the transducer 100 since the reflected ultrasonic signal excites the membrane 104 to perform an oscillation .

[0167] This periodic membrane displacement 4 caused by the reflected ultrasonic signal can be converted to an electrical signal by the piezoelectric element 102 . Thus , by measuring a time between emitting the ultrasonic signal 105 and receiving the reflected ultrasonic signal , a distance to the obj ect can be measured, considering a constant and known speed of sound .

[0168] To achieve precise results of the distance measurement , the membrane 104 is required to be sensitive to the reflected ultrasonic signal , i . e . the membrane 104 preferably does essentially not move and is at rest . However, after having been excited by the burst signal 11 , the membrane 104 P2024 , 1072 WO N November 6 , 2025

[0169] 34 continues to oscillate . This post-excitation displacement of the membrane 104 is also known as ringing . Especially for measuring distances to close obj ects , for example below 10 cm or closer, the ringing has to be damped, since the ringing would superimpose the reflected ultrasonic signal , making precise distance measuring challenging .

[0170] For achieving ef ficient damping of the ringing, the controlling device 1 is configured to generate a damping signal 12 based on a ringing behavior of the membrane 104 and to apply the damping signal 12 to the membrane 104 . Preferably, the damping signal 12 excites a damping mode 44 in the membrane 104 that has a higher energy dissipation than the sending mode 43 , which is excited by the burst signal 11 to generate the ultrasonic signal 105 . Further preferably, the housing 103 is constructed such that both the sending mode 43 and damping mode 44 are stable , so that both an ef ficient generation of the ultrasonic signal 105 and an ef ficient damping is possible .

[0171] The controlling device 1 according to a first exemplary embodiment as illustrated in Figure 2 , comprises an actuating element 2 configured to apply the burst signal 11 to the transducer 100 . The actuating element 2 is further configured to apply the damping signal 12 to the transducer 100 .

[0172] The damping signal 12 preferably comprises a plurality of pulses , each comprising a width 16 ( cf . Figure 3 ) . In particular, Figure 3 illustrates electronic membrane displacement signals corresponding to the membrane displacement 4 , 43 , 44 and the damping signal 12 . P2024 , 1072 WO N November 6 , 2025

[0173] 35

[0174] The controlling device 1 is configured to apply the damping signal 12 in three states , a positive state 13 , a negative state 15 , and a neutral state 14 . A pulse is for example defined by the damping signal 12 being in a positive state 13 or negative state 15 for a certain period of time , yielding the corresponding width 16 .

[0175] The pulses of the damping signal 12 are centered around peak point positions 41 of the periodic membrane displacement 4 during ringing in the sending mode 43 . At the peak point positions 41 the membrane 104 has a relatively low velocity, as a result of which influencing the membrane displacement 4 is particularly ef fective .

[0176] At the peak point positions 41 the damping signal 12 has an amplitude opposite to the membrane displacement 4 in the sending mode 43 . This means that , i f a certain peak point position 41 is a local maximum, the damping signal 12 is in the negative state 15 , and, i f another certain peak point position 41 is a local minimum, the damping signal 12 is in the positive state 13 . Between the positive states 13 and negative states 15 , the damping signal 12 is in the neutral state 14 , where an amplitude of the damping signal 12 is essentially zero .

[0177] The width 16 of the pulses of the damping signal 12 is lower than hal f a period 45 of the periodic membrane displacement 4 during ringing . The period 45 is a period of time between two peak point positions 41 , for example .

[0178] Preferably, the widths 16 of the pulses of the damping signal 12 are adj usted based on an amplitude of the membrane displacement signal , also referred to as feedback signal , P2024, 1072 WO N November 6, 2025

[0179] 36 corresponding to the membrane displacement 4. For example, when the amplitude of the membrane displacement 4 is low, the width 16 of the pulses may be reduced, and when the amplitude of the membrane displacement 4 is high, the width 16 of the pulses may be increased.

[0180] Advantageously, such an adaptive adaption of the widths 16 for an efficient damping, which is in particular tailored to actual vibration and oscillation of the membrane 104, thus enhancing overall performance and energy efficiency.

[0181] By the damping signal 12, the mode of the membrane displacement 4 can be changed, as illustrated in Figure 3. This means that, at the peak point positions 41, energy can be transferred from the sending mode 43 to the damping mode 44. During ringing, the membrane 4 oscillates in the sending mode 43 if no damping is applied. Thus, by applying the damping signal 12, energy of the membrane displacement 4 can be transferred to the damping mode 44 having increased energy dissipation. Thus, applying the damping signal 12 allows for an efficient energy dissipation.

[0182] Referring back to Figure 2, the actuating element 2 comprises a first buffer 21, in which raw data for the damping signal 12 are stored. For example, the peak point positions 41 of the membrane displacement 4 or the membrane displacement signal, the pulse width 16 and the state 13, 14, 15 of the damping signal 12 at each peak point position 41 are stored in the first buffer 21. From this information the damping signal 12 can be constructed.

[0183] In particular, the peak point positions 41 are time stamps and the widths 16 are measured in arbitrary time units. To P2024, 1072 WO N November 6, 2025

[0184] 37 assign time stamps to the peak point positions 41 and to construct the damping signal 12 as a chronological sequence of pulses, the controlling device 1 comprises a timer 5. The timer 5 provides a clock signal, which serves as a time resolution of the controlling device.

[0185] Preferably, the time resolution is at least ten times higher than a frequency of the ultrasonic signal 105. For example, the ultrasonic signal 105 has a frequency between 50 kHz and 100 kHz, for example 80 kHz. In this case, the time resolution of the timer is, for example, 1 ms-l.

[0186] The actuating element 2 comprises a signal generator 22 configured to generate the damping signal 12 from the raw data stored in the first buffer 21 and the clock signal provided by the timer 5. For example, the signal generator 22 generates a sequence of integers, where each integer stands for one of the states 13, 14, 15 of the damping signal 12 at each point in time according to the clock signal.

[0187] The signal generator 22 is connected to a driver 6, which may be part of the actuating element 2 and / or the controlling device 1. It is also possible that the driver 6 is a separate element .

[0188] The driver 6 in particular comprises a plurality of switches by which the sequence of numbers provided by the signal generator, i.e. the damping signal 12, is transformed into an electrical or electronic signal that is applied to the piezoelectric element 102. For example, each state 13, 14, 15 of the damping signal 12 is assigned a voltage of the electrical signal. P2024 , 1072 WO N November 6 , 2025

[0189] 38

[0190] Similar to the damping signal 12 , it is possible that the burst signal 11 is generated from raw data stored in the first buf fer 21 by the signal generator 22 and the timer 5 . The burst signal 11 may also be trans formed into an electrical or electronic signal by the driver 6 and subsequently applied to the piezoelectric element 102 .

[0191] For generating the damping signal 12 from the membrane displacement 4 , i . e . the membrane displacement signal , during ringing, the controlling device 1 further comprises a feedback element 3 . The feedback element 3 is in particular configured to determine the peak point positions 41 so that pulses of the damping signal 12 can be assigned to the peak point positions 41 .

[0192] Determining the peak point positions 41 is carried out by means of a comparator 31 . The comparator 31 may be part of the feedback element 3 and / or the controlling device 1 or may be a separate component . The comparator 31 is configured to compare an electrical signal provided by the piezoelectric element 102 and corresponding to a membrane displacement 4 to a zero value . At these points in time , the periodic membrane displacement 4 comprises a zero-crossing point position 42 .

[0193] Each peak point position 41 can be calculated from the adj acent zero-crossing point positions 42 by taking a median value of these zero-crossing point positions 42 . For example , a period between two zero-crossing point positions 42 , which corresponds to the period 45 of the membrane displacement 4 , is 10 arbitrary time units . In this example , a first zerocrossing point position 42 may be at a point in time that is 10 arbitrary time units , and a second zero-crossing point position 42 may be at 20 arbitrary time units . Thus , the P2024 , 1072 WO N November 6 , 2025

[0194] 39 associated peak point position 41 is at 15 arbitrary time units .

[0195] The feedback element 3 further comprises an edge capture unit 32 configured to determine whether an edge of the membrane displacement 4 or the membrane displacement signal is rising or falling at each zero-crossing point position 42 . From this information, it can be determined whether the preceding and subsequent peak point positions 41 correspond to a minimum or a maximum of the membrane displacement 4 .

[0196] I f , for example , the membrane displacement 4 or the membrane displacement signal is falling, i . e . has a negative gradient , at a speci fic zero-crossing point position 42 , the preceding peak point position 41 corresponds to a local maximum and the subsequent peak point position 41 corresponds to a local minimum . I f at another speci fic zero-crossing point position 42 the membrane displacement 4 or the membrane displacement signal is rising, i . e . has a positive gradient , the preceding peak point position 41 corresponds to a local minimum and the subsequent peak point position 41 corresponds to a local maximum . From this information, the state 13 , 15 of the damping signal 12 at each peak point position 41 can be obtained as described above .

[0197] The feedback element 3 further comprises a calculation unit 34 and a second buf fer 33 , which also can be one element . The calculation unit 34 is configured to calculate the raw data for the damping signal 12 from the information provided by the comparator 31 and the edge capture unit 32 . The second buf fer 33 is configured to store the information provided by the comparator 31 and the edge capture unit 32 and provide it to the calculation unit 34 . The second buf fer 33 can further P2024 , 1072 WO N November 6 , 2025

[0198] 40 be configured to store the raw data of the damping signal 12 .

[0199] The first and second buf fers 21 , 33 can be connected or can even be a common storage element .

[0200] The controlling device 1 is preferably part of an electronic component 200 . For example , the electronic component 200 is a microcontroller, an application speci fic integrated circuit (AS IC ) or a field programmable gate array ( FPGA) , or a computer with suitable hardware for signal generation and acquisition . For example , the controlling device 1 comprises the actuating element 2 , the feedback element 3 and the timer 5 . The driver 6 and the comparator 31 may be individual elements of the electronic component . It is also possible that the driver 6 and / or the comparator 31 are part of the controlling device 1 .

[0201] The electronic component 200 further comprises an analog-to- digital converter, ADC, 7 and at least one filter unit 8 . By the ADC 7 and the filter unit 8 , the electrical signal provided by the piezoelectric element 102 corresponding to the membrane displacement 4 can be digiti zed and processed for evaluation, for example to carry out a distance measurement . This evaluation can be carried out by a digital signal processor 101 , which may be part of the electronic component 200 or may be a distinct further electronic component .

[0202] The controlling device 1 according to the second exemplary embodiment as illustrated in Figure 4 essentially comprises the same features as the controlling device 1 according to the first exemplary embodiment and is further configured to adapt the damping signal 12 , i f , for example , environmental conditions of the transducer 100 change . For example , a P2024 , 1072 WO N November 6 , 2025

[0203] 41 temperature and / or an ambient pressure of the transducer' s environment may change . This may happen i f the transducer is used, for example , in a car .

[0204] Such a change in environmental conditions may change a resonance frequency of the membrane 104 of the transducer, as a result of which the sending mode 43 and the membrane displacement 4 during ringing may change . Consequently, the damping signal 12 may not provide ef ficient enough damping to make precise measurements of small distances possible . Thus , adaption of the damping signal 12 is desired .

[0205] The electronic component 200 or the controlling device 1 further comprises a threshold unit 35 that is configured to detect whether a swinging characteristic 40 of the membrane displacement 4 exceeds a predefined threshold . I f the threshold is exceeded, the threshold unit 35 triggers an adaption of the damping signal 12 . For example , the damping signal 12 is adapted by generating a new damping signal 12 by means of the feedback element 3 as discussed in connection with the first exemplary embodiment .

[0206] The swinging characteristic 40 is preferably an envelope function corresponding to an amplitude of the membrane displacement 4 during ringing . The envelope function is preferably generated by the ADC 7 and the filter unit 8 .

[0207] Figures 5 to 11 illustrate the ef fect of adapting the damping signal .

[0208] Figure 5 shows an amplitude of the membrane displacement 4 during operation as raw data of a membrane displacement signal corresponding to the membrane displacement 4 . For P2024 , 1072 WO N November 6 , 2025

[0209] - 42 - example , the membrane displacement signal is obtained and provided by the piezoelectric element 102 as a result of the membrane displacement 4 .

[0210] During an excitation period 51 of the operation, the burst signal 11 is applied ( cf . Figures 5 and 6 ) . The burst signal 11 comprises a sequence of alternating rectangular pulses to excite the sending mode 43 and to generate the ultrasonic signal 105 .

[0211] Subsequent to the excitation period 51 , the membrane displacement 4 is damped using the damping signal 12 during a damping period 52 . At a stopping point 54 at the end of the damping period 52 the damping signal 12 is terminated in order to avoid revibration of the membrane 104 in an opposite direction . After termination of the damping period 52 , the membrane 104 may still show residuals of the ringing in a free ringing period 53 , in which no signal is applied to the piezoelectric element 102 .

[0212] The damping signal 12 comprises a first part 121 and a second part 122 . In the first part 121 , the damping signal 12 comprises pulses of a first kind 123 , and in the second part 122 , the damping signal 12 comprises pulses of a second kind 124 .

[0213] The pulses of the first kind 123 are counter pulses to the pulses of the burst signal 11 , i . e . the first part 121 corresponds to a 180 ° shi fted burst signal 11 .

[0214] The pulses of the second kind 124 vary in width . In particular, the second part 122 is generated by the feedback element 3 as discussed above . P2024 , 1072 WO N November 6 , 2025

[0215] 43

[0216] By the first part 121 , initial energy of the ringing membrane 104 can be reduced, making the membrane 104 more sensitive for damping via the second part 122 .

[0217] Figure 7 shows the switching characteristic 40 as an envelope function determined from the membrane displacement 4 . The curve 46 corresponds to a free envelope function that is obtained with no obj ect inside a region to be measured . The curve 47 corresponds to an obj ect envelope function that is obtained i f an obj ect to which the distance is to be measured is arranged in front of the transducer 100 . From the di f ference between the curves 46 , 47 the digital signal processor can calculate the distance to the obj ect .

[0218] As can be seen in Figure 7 , the damping by the damping signal 12 is ef ficient since the curve 47 can be clearly distinguished from the curve 46 .

[0219] In Figures 8 and 9 , for example environmental conditions of the transducer 100 have changed such that the damping is not suf ficient . A comparison of Figures 8 and 6 shows that in the free ringing period 53 the amplitude of the membrane displacement 4 is increased . A comparison of Figures 7 and 9 shows that the distance to the obj ect cannot be measured since the curves 46 , 47 cannot be clearly distinguished .

[0220] Thus , small distances cannot be precisely measured since the reflected ultrasonic signal has to be detected during the free ringing period 53 . Therefore , the threshold unit 35 monitors the swinging characteristic preferably in a monitoring region that corresponds to the free ringing period . P2024 , 1072 WO N November 6 , 2025

[0221] 44

[0222] In Figures 10 and 11 , the damping signal 12 is adapted to the new environmental conditions . A comparison of Figures 10 and 8 shows that in the free ringing period 53 the amplitude of the membrane displacement 4 is again decreased . A comparison of Figures 11 and 9 shows that the distance to the obj ect cannot be precisely measured since the curves 46 , 47 cannot be clearly distinguished . Thus , precise measurement of the distance to the obj ect is again possible .

[0223] Figure 12 illustrates a closed-loop control algorithm for operating a controlling device 1 described herein . In a step 301 raw data of the burst signal 11 and the damping signal 12 are provided, for example by the first buf fer 21 .

[0224] In step 302 the burst signal 11 and the damping signal 12 are generated by the signal generator 22 .

[0225] By the steps 301 and 302 step 301 , the burst signal 11 and the damping signal are provided . The burst signal 11 and the damping signal 12 are provided to a piezoelectric element 102 or a membrane 104 of a transducer 100 .

[0226] In a further step 303 , the swinging characteristic 40 is determined from the membrane displacement signal . In a further step 304 , it is determined i f a change in the swinging characteristic 40 exceeds the predetermined threshold by the threshold unit 35 .

[0227] I f the threshold is exceeded, an adapted damping signal 12 is generated from the membrane displacement signal by determining peak point positions of the membrane displacement P2024 , 1072 WO N November 6 , 2025

[0228] 45 signal in step 305 . These data may be provided in a subsequent execution of step 301 .

[0229] I f the threshold is not exceeded, a subsequent execution of step 301 can be carried out without adapting the damping signal 12 . Thus , step 301 may follow step 304 .

[0230] The invention is not restricted to the exemplary embodiments by the description on the basis of said exemplary embodiments . Rather, the invention encompasses any new feature and also any combination of features , which in particular comprises any combination of features in the patent claims and any combination of features in the exemplary embodiments , even i f this feature or this combination itsel f is not explicitly speci fied in the patent claims or exemplary embodiments .

[0231] P2024 , 1072 WO N November 6 , 2025

[0232] 46

[0233] References

[0234] 1 controlling device

[0235] 2 actuating element

[0236] 3 feedback element

[0237] 4 membrane displacement

[0238] 5 timer

[0239] 6 driver

[0240] 7 analog-to-digital converter

[0241] 8 filter unit

[0242] 11 burst signal

[0243] 12 damping signal

[0244] 13 positive state

[0245] 14 neutral state

[0246] 15 negative state

[0247] 16 pulse width

[0248] 21 first buf fer

[0249] 22 signal generator

[0250] 31 comparator

[0251] 32 edge capture unit

[0252] 33 second buf fer

[0253] 34 calculation unit

[0254] 35 threshold unit

[0255] 40 swinging characteristic

[0256] 41 peak point position

[0257] 42 zero-crossing point position

[0258] 43 sending mode

[0259] 44 damping mode

[0260] 45 period of periodic membrane displacement

[0261] 46 free envelope function

[0262] 47 obj ect envelope function

[0263] 50 time

[0264] 51 excitation period P2024 , 1072 WO N November 6 , 2025

[0265] 47

[0266] 52 damping period

[0267] 53 free ringing period

[0268] 54 stopping point

[0269] 100 ultrasonic transducer 101 signal processor

[0270] 102 piezoelectric element

[0271] 103 housing

[0272] 104 membrane

[0273] 105 ultrasonic signal 121 first part of damping signal

[0274] 122 second part of damping signal

[0275] 123 pulse of first kind

[0276] 124 pulse of second kind

[0277] 200 electronic component

[0278] 301...305 method steps

Claims

P2024, 1072 WO N November 6, 202548Claims1. Controlling device (1) for an ultrasonic transducer (100) , comprising:- an actuating element (2) configured to apply a burst signal (11) to the transducer (100) for generating and sending an ultrasonic signal (105) , and apply a damping signal (12) to the transducer (100) for damping a periodic membrane displacement (4) after sending the ultrasonic signal (105) ,- a feedback element (3) configured to generate the damping signal (12) by determining peak point positions (41) of a membrane displacement (4) after termination of exciting the membrane, and generate the damping signal (12) comprising a sequence of pulses such that each pulse is centered around one peak point position (41) .

2. Controlling device (1) according to claim 1, wherein the feedback element (3) is further configured to monitor at least one swinging characteristic (40) of a membrane (104) of the transducer (100) during operation, and, if the swinging characteristic (40) changes above a predetermined threshold, generate an adapted damping signal (12) .

3. Controlling device (1) according to claim 2, wherein the adapted damping signal (12) is generated between the application of two subsequent burst signals (11) .

4. Controlling device (1) according to one of the preceding claims, wherein the actuating element (2) is configured to provide the burst signal (11) and the damping signal (12) in a common pulse sequence.P2024, 1072 WO N November 6, 2025495. Controlling device (1) according to one of the preceding claims, wherein the feedback element (3) is configured to generate and adjust the damping signal (12) independently of a resonance of the membrane displacement (4) .

6. Controlling device (1) according to one of the preceding claims , wherein the actuating element (2) is configured to provide at least the damping signal (12) in at least one positive state(13) , at least one negative state (15) and at least one neutral state (14) , wherein the actuating element (2) is configured to apply a pulse of the damping signal (12) in the positive state (13) if the corresponding peak point (41) of the membrane displacement (4) is a local minimum, a pulse of the damping signal (12) in the negative state (15) if the corresponding peak point (41) of the membrane displacement (4) is a local maximum, and the damping signal (12) in the neutral state(14) if the membrane displacement (4) comprises a zerocrossing .

7. Controlling device (1) according to one of the preceding claims, further comprising a timer (5) configured to provide a clock signal, wherein the peak point positions (41) are determined by means of the clock signal.

8. Controlling device (1) according to claim 7, wherein a time resolution of the timer (5) is at least ten times higher than an operation frequency of the ultrasonic transducer(100) .P2024, 1072 WO N November 6, 2025509. Controlling device (1) according to one of the preceding claims, wherein the actuating element (2) comprises a first buffer (21) configured to store raw data of the burst signal (11) and the damping signal (12) .

10. Controlling device (1) according to claim 9 and claim 7 or 8, wherein the actuating element (2) further comprises a signal generator (22) configured to generate the burst signal (11) and the damping signal (12) as a chronological pulse sequence by means of the raw data of the burst signal and the damping signal and the clock signal.

11. Controlling device (1) according to one of the preceding claims, wherein the feedback element (3) is configured to determine peak point positions (41) of the membrane displacement (4) by detecting zero-crossing point positions (42) of the membrane displacement (4) and calculating a median between two adjacent zero-crossing point positions (42) .

12. Controlling device (1) according to claim 7 and claim 11, wherein the zero-crossing point positions (42) are determined by means of a comparator (31) and the clock signal .

13. Controlling device (1) according to claim 11 or 12, wherein the feedback element (3) is configured to adapt the damping signal (12) in each interval between two adjacent zero-crossing points (42) , in particular regarding widths of the pulses of the damping signal (12) .

14. Controlling device (1) according to one of the preceding claims, wherein the feedback element (3) is configured toP2024, 1072 WO N November 6, 2025- 51 - generate or adjust widths of the pulses of the damping signal (12) based on an amplitude of the periodic membrane displacement (4) .

15. Controlling device (1) according to one of the preceding claims, wherein the feedback element (3) is configured to generate the damping signal (12) to comprise pulses with a width lower than half of a period of the periodic membrane displacement (4) .

16. Controlling device (1) according to one of the preceding claims in connection with claim 6, wherein the feedback element (3) comprises an edge capture unit (32) configured to determine an edge orientation of the periodic membrane displacement (4) at a zero-crossing point position (42) , and wherein a state (13, 14, 15) of the damping signal (12) is adjusted according to the edge orientation.

17. Controlling device (1) according to claim 16, wherein the feedback element (3) comprises- a second buffer (33) configured to store peak positions(41) and the edge orientation, and- a calculation unit (34) configured to determine the damping signal (12) based on data stored in the second buffer (33) .

18. Controlling device (1) according to one of the preceding claims, wherein the damping signal (12) comprising a first part (121) and a second part (122) , wherein in the first part (121) the damping signal comprises pulses of a first kind (123) and in the second part (122) the damping signal comprises pulses of a second kind (124) , wherein pulses of the second kind (124) have a smaller width than pulses of the first kind (123) , andP2024, 1072 WO N November 6, 2025- 52 - wherein the second part (122) is applied subsequent to the first part (121) .

19. Controlling device (1) according to claim 18, wherein the feedback element (3) is configured to adapt the second part (122) based on an amplitude of the membrane displacement (4) , and the first part (121) is a fixed part unadapted by the feedback element (3) .

20. Controlling device (1) according to one of the preceding claims, wherein the controlling device (1) is configured to excite a damping mode (44) by applying the damping signal (12) having a higher energy dissipation than a sending mode (43) excited by applying the burst signal (11) .

21. Method for operating an ultrasonic transducer (100) comprising a controlling device (1) according to one of the preceding claims, comprising the steps of- exciting a membrane (104) of the transducer (100) for generating and sending an ultrasonic signal (105) by applying a burst signal (11) to the membrane (104) ,- damping the membrane (104) after sending the ultrasonic signal (105) by applying a damping signal (12) , wherein the damping signal (12) is generated by determining peak point positions (41) of a membrane displacement (4) after termination of exciting the membrane, wherein the damping signal (12) comprises a chronological sequence of pulses, wherein each pulse is centered around one peak point position (41) .

22. Method according to claim 21, further comprising the steps ofP2024, 1072 WO N November 6, 202553- monitoring a swinging characteristic (40) of the membrane, and- adapting the damping signal (12) if the swinging characteristic (40) changes above a predetermined threshold.

23. Method according to claim 21 or 22, wherein peak point positions (41) of the membrane displacement (4) are determined by detecting zero-crossing point positions (42) of the membrane displacement (4) and calculating a median between two adjacent zero-crossing point positions (42) .

24. Ultrasonic transducer (100) comprising a controlling device (1) according to one of claims 1 to 20.

25. Method for using an ultrasonic transducer (100) according to claim 24 for a distance measurement obtaining a distance from the transducer (100) to an object, wherein the distance is between 3 cm and 2 m, inclusive.

26. Electronic component (200) comprising at least one controlling device (1) according to one of claims 1 to 20.

27. Electronic component (200) according to claim 26, comprising a microcontroller, an application specific integrated circuit, ASIC, a field programmable gate array , FPGA, or a computer having means configured for signal generation and acquisition.

28. Computer-implemented method for operating a controlling device (1) according to one of claims 1 to 20, comprising the steps of providing a burst signal (11) and a damping signal (12) by- reading raw data of the burst signal (11) and the dampingP2024, 1072 WO N November 6, 202554 signal (12) from a first buffer (21) , and- generating the burst signal (11) and the damping signal(12) by the signal generator (22) ; generating the raw data of the damping signal (12) by determining peak point positions (41) of a membrane displacement signal.

29. Data processing device comprising means for carrying out the computer-implemented method of claim 28.

30. Computer program comprising instructions which, when the program is executed by a computer, cause to computer to carry out the computer-implemented method of claim 28.

31. Computer-readable storage media having stored thereon the computer program according to claim 30.

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