Integrated haptic system

Abstract

An integrated haptic system may include a digital signal processor and an amplifier communicatively coupled to the digital signal processor and integrated into the integrated haptic system with the digital signal processor. The digital signal processor may be configured to receive a force sensor signal indicating a force applied to the force sensor and generate a haptic playback signal in response to the force. The amplifier may be configured to amplify the haptic playback signal and drive a vibration actuator communicatively coupled to the amplifier using the haptic playback signal amplified by the amplifier.

Description

[0001] Related Applications

[0002] The present disclosure is a divisional application of a patent application with a filing date of May 7, 2018, application number 201880037435.X, and name “Integrated Haptic System”.

[0003] The present disclosure is a continuation of U.S. non-provisional patent application No. 16 / 871,832 filed on May 11, 2020, which is a part of U.S. non-provisional patent application No. 15 / 722,128 filed on October 2, 2017, and published on August 4, 2020 as U.S. Patent No. 10,732,714, which is based on U.S. Provisional Patent Application No. 62 / 503,163 filed on May 8, 2017 and U.S. Provisional Patent Application No. 62 / 540,921 filed on August 3, 2017.

[0004] The present disclosure is based on U.S. Provisional Patent Application No. 62 / 503,163 filed on May 8, 2017, U.S. Provisional Patent Application No. 62 / 540,921 filed on August 3, 2017, and U.S. Non-Provisional Patent Application No. 15 / 722,128 filed on October 2, 2017 as priority, the entire contents of which are incorporated into the present disclosure by reference. Technical Field

[0005] The present disclosure relates generally to electronic devices with user interfaces (e.g., mobile devices, game controllers, instrument panels, etc.), and more specifically to systems for mechanical button replacement in mobile devices, integrated tactile systems for tactile feedback of capacitive sensors, and / or other suitable applications. Background Art

[0006] Linear resonant actuators (LRAs) and other vibration actuators (e.g., rotary actuators, vibration motors, etc.) are increasingly being used in mobile devices (e.g., mobile phones, personal digital assistants, video game controllers, etc.) to generate vibration feedback for user interaction with such devices. Typically, a force / pressure sensor detects user interaction with the device (e.g., a finger press on a virtual button of the device), and in response thereto, the linear resonant actuator vibrates to provide feedback to the user. For example, a linear resonant actuator may vibrate in response to a force to simulate the feel of a mechanical button click to the user.

[0007] One disadvantage of existing haptic systems is that existing methods for processing signals from force sensors and generating haptic responses thereto typically have a longer latency than desired, such that the haptic response can be significantly delayed from the user's interaction with the force sensor. As a result, in applications where the haptic system is used for mechanical button replacement, capacitive sensor feedback, or other applications, the haptic response cannot effectively mimic the feel of a mechanical button click. Therefore, systems and methods are desired that minimize the latency between a user's interaction with a force sensor and a haptic response to that interaction.

[0008] Additionally, the signals driving the linear resonant actuator need to be carefully designed and generated to create an appropriate and pleasing tactile sensation for the user. In a mechanical button replacement application, an ideal tactile response may be one in which the vibration pulse generated by the linear resonant actuator should be strong enough to give the user noticeable notification in response to his / her finger pressing and / or releasing, and the vibration pulse should be short, fast, and without a resonant tail to provide a "sharp" and "crisp" feeling to the user. Optionally, different control algorithms and excitations may be applied to the linear resonant actuator to vary the performance to provide alternating tactile feedback - perhaps indicative of certain user patterns in the device - thereby providing more "soft" and "resonant" tactile responses. Summary of the invention

[0009] According to the teachings of the present disclosure, disadvantages and problems associated with haptic feedback in mobile devices may be reduced or eliminated.

[0010] According to an embodiment of the present disclosure, an integrated haptic system may include a digital signal processor and an amplifier communicatively coupled to the digital signal processor and integrated into the integrated haptic system with the digital signal processor. The digital signal processor may be configured to receive an input signal indicating a force applied to a force sensor, and generate a haptic playback signal in response to the input signal. The amplifier may be configured to amplify the haptic playback signal, and drive a vibration actuator communicatively coupled to the amplifier using the haptic playback signal amplified by the amplifier.

[0011] According to these and other embodiments of the present disclosure, a method may include receiving, by a digital signal processor, an input signal indicating a force applied to a force sensor. The method may also include generating, by the digital signal processor, a tactile playback signal in response to the input signal. The method may further include driving, using an amplifier communicatively coupled to the digital signal processor and integrated with the digital signal processor into an integrated tactile system, the tactile playback signal amplified by the amplifier.

[0012] According to these and other embodiments of the present disclosure, an article of manufacture may include a non-transitory computer-readable medium carrying computer-executable instructions, which are readable by a processor and, when read and executed, are used to cause the processor to perform the following operations: receive an input signal indicating a force applied to a force sensor; and generate a tactile playback signal in response to the input signal, so that an amplifier can be communicatively coupled to the processor and integrated with a digital signal processor into an integrated tactile system to amplify and drive the tactile playback signal.

[0013] According to the drawings, descriptions and claims included herein, the technical advantages of the present disclosure will be obvious to those of ordinary skill in the art. The objects and advantages of the embodiments will be realized and achieved at least by the elements, features and combinations specifically pointed out in the claims.

[0014] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the disclosure, as claimed. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] A more complete understanding of embodiments of the present invention and its advantages may be obtained by referring to the following description taken in conjunction with the accompanying drawings, wherein like reference numerals indicate like features, and wherein:

[0016] Figure 1 A block diagram illustrating selected components of an example mobile device according to an embodiment of the present disclosure;

[0017] Figure 2 A block diagram illustrating selected components of an example integrated haptic system according to an embodiment of the present disclosure;

[0018] Figure 3 The method for Figure 2 A block diagram of selected components of an example processing system for an integrated haptic system;

[0019] Figure 4 A block diagram illustrating selected components of another example integrated haptic system according to an embodiment of the present disclosure;

[0020] Figure 5 shows a graph illustrating example waveforms of haptic drive signals that may be generated according to an embodiment of the present disclosure;

[0021] Figure 6 showing a graph depicting an example transfer function of a linear resonant actuator depicting displacement as a function of frequency at a voltage level equal to a maximum static excursion occurring at low frequencies in accordance with an embodiment of the present disclosure;

[0022] Figure 7shows a graph depicting an example transfer function of acceleration of a linear resonant actuator as a function of frequency and maximum acceleration at maximum excursion according to an embodiment of the present disclosure;

[0023] Figure 8 A block diagram illustrating selected components of another example integrated haptic system according to an embodiment of the present disclosure;

[0024] Fig. 9 A block diagram illustrating selected components of another example integrated haptic system according to an embodiment of the present disclosure;

[0025] Fig.10 a block diagram illustrating selected components of another example integrated haptic system according to an embodiment of the present disclosure; and

[0026] Fig.11 A block diagram illustrating selected components of another example integrated haptic system according to an embodiment of the disclosure. DETAILED DESCRIPTION

[0027] Figure 1 1 is a block diagram illustrating selected components of an example mobile device 102 according to an embodiment of the present disclosure. Figure 1 As shown, mobile device 102 may include housing 101 , controller 103 , memory 104 , force sensor 105 , microphone 106 , linear resonant actuator 107 , radio transmitter / receiver 108 , speaker 110 , and integrated haptic system 112 .

[0028] The housing 101 may include any suitable shell, housing, or other enclosure for housing the various components of the mobile device 102. The housing 101 may be constructed of plastic, metal, and / or any other suitable material. In addition, the housing 101 may be adapted (e.g., sized and shaped) such that the mobile device 102 may be easily transported on the user of the mobile device 102. Thus, the mobile device 102 may include, but is not limited to, a smartphone, a tablet computing device, a handheld computing device, a personal digital assistant, a laptop computer, a video game controller, or any other device that is easily transported on the user of the mobile device 102.

[0029] The controller 103 may be housed within the housing 101 and may include any system, device or apparatus configured to interpret and / or execute program instructions and / or process data, and may include, but is not limited to, a microprocessor, a microcontroller, a digital signal processor (DSP), an application specific integrated circuit (ASIC), or any other digital or analog circuit configured to interpret and / or execute program instructions and / or process data. In some embodiments, the controller 103 interprets and / or executes program instructions and / or processes data stored in the memory 104 and / or other computer-readable media accessible to the controller 103.

[0030] The memory 104 may be housed within the housing 101, communicatively coupled to the controller 103, and may include any system, device, or apparatus (e.g., a computer-readable medium) configured to retain program instructions and / or data for a period of time. The memory 104 may include random access memory (RAM), electrically erasable programmable read-only memory (EEPROM), a personal computer memory card international association (PCMCIA) card, flash memory, magnetic memory, optoelectronic memory, or any suitable selection and / or array of volatile or non-volatile memory that retains data after power to the mobile device 102 is turned off.

[0031] Microphone 106 may be at least partially housed in housing 101, communicatively coupled to controller 103, and may include any system, device, or apparatus configured to convert sound incident at microphone 106 into an electrical signal that may be processed by controller 103, wherein such sound is converted into the electrical signal using a diaphragm or membrane having a capacitance that varies according to the vibration of sound received at the diaphragm or membrane. Microphone 106 may include an electrostatic microphone, a condenser microphone, an electret microphone, a micro-electromechanical system (MEM) microphone, or any other suitable capacitive microphone.

[0032] The radio transmitter / receiver 108 may be housed within the housing 101, communicatively coupled to the controller 103, and may include a device configured to generate and transmit radio frequency signals with the aid of an antenna, and to receive radio frequency signals and convert information carried by such received signals into a form usable by the controller 103. The radio transmitter / receiver 108 may be configured to transmit and / or receive various types of radio frequency signals, including but not limited to cellular communications (e.g., 2G, 3G, 4G, LTE, etc.), short-range wireless communications (e.g., BLUETOOTH), commercial radio signals, television signals, satellite radio signals (e.g., GPS), Wi-Fi, etc.

[0033] The speaker 110 may be at least partially housed within the housing 101 or may be external to the housing 101, communicatively coupled to the controller 103, and may include any system, device, or apparatus configured to produce sound in response to an electrical audio signal input. In some embodiments, the speaker may include a dynamic speaker that employs a lightweight diaphragm mechanically coupled to a rigid frame via a flexible suspension that constrains a voice coil to move axially through a cylindrical magnetic gap. When an electrical signal is applied to the voice coil, the current in the voice coil generates a magnetic field, causing it to become a variable electromagnet. The magnetic systems of the coil and the driver interact, generating a mechanical force that moves the coil (and therefore the attached cone) back and forth, reproducing sound under the control of the applied electrical signal from the amplifier.

[0034] The force sensor 105 may be housed within the housing 101 and may include any suitable system, device, or apparatus for sensing force, pressure, or touch (e.g., interaction with a person's finger) and generating an electrical or electronic signal in response to such force, pressure, or touch. In some embodiments, such electrical or electronic signals may be a function of the magnitude of the force, pressure, or touch applied to the force sensor. In these and other embodiments, such electrical or electronic signals may include general purpose input / output signals (GPIO) associated with input signals that are given tactile feedback (e.g., a capacitive touch screen sensor or other capacitive sensor that is given tactile feedback). For purposes of clarity and illustration in this disclosure, the term "force" as used herein may refer not only to force, but also to physical quantities that indicate force or are similar to force, such as, but not limited to, pressure and touch.

[0035] The linear resonant actuator 107 may be housed within the housing 101 and may include any suitable system, device, or apparatus for generating an oscillating mechanical force across a single axis. For example, in some embodiments, the linear resonant actuator 107 may rely on an AC voltage to drive a voice coil pressed against a moving mass connected to a spring. When the voice coil is driven at the resonant frequency of the spring, the linear resonant actuator 107 may vibrate with a perceptible force. Therefore, the linear resonant actuator 107 may be useful in tactile applications within a specific frequency range. Although the present disclosure is described with respect to the use of a linear resonant actuator 107 for purposes of clarity and illustration, it should be understood that any one or more other types of vibration actuators (e.g., eccentric rotating mass actuators) may be used in place of or in addition to the linear resonant actuator 107. In addition, it should also be understood that an actuator arranged to generate an oscillating mechanical force across multiple axes may be used in place of or in addition to the linear resonant actuator 107. As described elsewhere in this disclosure, based on signals received from the integrated haptic system 112 , the linear resonant actuator 107 can present tactile feedback to a user of the mobile device 102 for at least one of mechanical button replacement and capacitive sensor feedback.

[0036] Integrated haptic system 112 may be housed within housing 101, may be communicatively coupled to force sensor 105 and linear resonant actuator 107, and may include any system, device, or apparatus configured to receive a signal from force sensor 105 indicating a force applied to mobile device 102 (e.g., a force applied by a human finger to a virtual button of mobile device 102) and generate an electronic signal for driving linear resonant actuator 107 in response to the force applied to mobile device 102. Figure 2 Details of an example integrated haptic system according to embodiments of the present disclosure are depicted in FIG.

[0037] Despite the above Figure 1 104, user interface 105, microphone 106, radio transmitter / receiver 108, speaker(s) 110), mobile device 102 according to embodiments of the present disclosure may include one or more components not specifically listed above. Figure 1 Certain user interface components are depicted, but mobile device 102 may include Figure 1 One or more other user interface components beyond those depicted, including, but not limited to, a keypad, a touch screen, and a display, allow a user to interact with and / or otherwise manipulate the mobile device 102 and its associated components.

[0038] Figure 2 A block diagram showing selected components of an example integrated haptic system 112A according to an embodiment of the present disclosure. In some embodiments, the integrated haptic system 112A may be used to implement Figure 1 The integrated tactile system 112. Figure 2 As shown, the integrated haptic system 112A may include a digital signal processor (DSP) 202 , a memory 204 , and an amplifier 206 .

[0039] DSP 202 may include any system, device or apparatus configured to interpret and / or execute program instructions and / or process data. In some embodiments, DSP 202 may interpret and / or execute program instructions and / or process data stored in memory 204 and / or other computer-readable media accessible to DSP 202.

[0040] The memory 204 may be communicatively coupled to the DSP 202 and may include any system, device, or apparatus (e.g., a computer-readable medium) configured to retain program instructions and / or data for a period of time. The memory 204 may include random access memory (RAM), electrically erasable programmable read-only memory (EEPROM), a Personal Computer Memory Card International Association (PCMCIA) card, flash memory, magnetic memory, optoelectronic memory, or any suitable selection and / or array of volatile or non-volatile memory that retains data after power to the mobile device 102 is turned off.

[0041] Amplifier 206 may be electrically coupled to DSP 202 and may include any suitable electronic system, device, or apparatus configured to increase the power (e.g., time-varying voltage or current) of an input signal VIN to generate an output signal VOUT. For example, amplifier 206 may use power from a power supply (not explicitly shown) to increase the amplitude of the signal. Amplifier 206 may include any suitable amplifier class, including but not limited to a Class D amplifier.

[0042] In operation, memory 204 may store one or more haptic playback waveforms. In some embodiments, each of the one or more haptic playback waveforms may define a haptic response a(t) as a desired acceleration of a linear resonant actuator (e.g., linear resonant actuator 107) as a function of time. DSP 202 may be configured to receive a force signal VSENSE from force sensor 105 indicating a force applied to force sensor 105. In response to receiving the force signal VSENSE indicating the sensed force, or independently of such receiving, DSP 202 may retrieve a haptic playback waveform from memory 104 and process the haptic playback waveform to determine a processed haptic playback signal VIN. In embodiments where amplifier 206 is a class D amplifier, the processed haptic playback signal VIN may include a pulse width modulated signal. In response to receiving the force signal VSENSE indicating the sensed force, DSP 202 may output a processed haptic playback signal VIN to amplifier 206 , and amplifier 206 may amplify the processed haptic playback signal VIN to generate a haptic output signal VOUT for driving linear resonant actuator 107 . Figure 3 Details of an example processing system implemented by DSP 202 are depicted in .

[0043] In some embodiments, the integrated haptic system 112A may be formed on a single integrated circuit, thereby achieving lower latency compared to existing haptic feedback control methods. By providing the integrated haptic system 112A as part of a single monolithic integrated circuit, latency between various interfaces and system components of the integrated haptic system 112A may be reduced or eliminated.

[0044] like Figure 3 As shown, DSP 202 may receive diagnostic inputs, and processing system 300 may monitor and adjust the operation of amplifier 206 in response to the diagnostic inputs. For example, as described below with respect to Figure 3As discussed, the DSP 202 may receive measurements from the linear resonant actuator 107 to estimate the vibration transfer function of the linear resonant actuator 107. However, in some embodiments, the DSP 202 may receive and monitor one or more other diagnostic inputs, and the DSP 202 may control the operation of the amplifier 206 in response thereto. For example, in some embodiments, the DSP 202 may monitor a current level associated with the linear resonant actuator 107 and / or a voltage level associated with the linear resonant actuator 107. Based on such measurements, the DSP 202 may be able to infer or calculate a state (e.g., a motion state) of the linear resonant actuator 107. For example, based on the monitored voltage and current, the DSP 202 may employ a mathematical model of the linear resonant actuator 107 to estimate the displacement, velocity, and / or acceleration of the linear resonant actuator 107. As another example, the DSP 202 may inject a high frequency signal into the linear resonant actuator 107 and infer the inductance of the linear resonant actuator 107 based on the current and / or voltage response of the linear resonant actuator 107 to the injected signal. Based on the inductance, DSP 202 may be able to estimate the displacement of linear resonant actuator 107. Based on the determined state information (e.g., displacement, velocity, and / or acceleration), DSP 202 may control the processed haptic playback signal VIN for any suitable purpose, including protecting linear resonant actuator 107 from excessive excursion, which may cause damage to linear resonant actuator 107 or other components of mobile device 101. As yet another example, one or more diagnostic inputs may be monitored to determine an operational drift of linear resonant actuator 107, and DSP 202 may control amplifier 206 and / or processed haptic playback signal VIN to account for the operational drift. As another example, one or more diagnostic inputs may be monitored to determine a temperature effect of linear resonant actuator 107 (e.g., a change in performance of linear resonant actuator 107 caused by heat), and DSP 202 may control amplifier 206 and / or processed haptic playback signal VIN to account for the temperature effect.

[0045] Figure 3 2 is a block diagram showing selected components of an example processing system 300 implemented by DSP 202 according to an embodiment of the present disclosure. Figure 3As shown, the processing system 300 may include a vibration pulse processing 302, an adjusted inversion 304, a click drive pulse processing 306, a comparator 308, and a vibration transfer function estimation 310. In operation, the vibration pulse processing 302 may receive a tactile playback waveform a(t) (or related parameters of such a waveform, such as frequency and duration), and process such a waveform to generate an intermediate signal a1(t). The processing performed by the vibration pulse processing 302 may include, but is not limited to, filtering of a frequency band of interest (e.g., bandpass filtering), equalizing the tactile playback waveform a(t) to obtain a desired spectral shape, and / or time truncation or extrapolation of the tactile playback waveform a(t). By adjusting or tuning the time duration and frequency envelope of the tactile playback waveform a(t), the audibility of various tactile sensations and / or tactile responses perceived by the user may be achieved.

[0046] The adjusted anti-phase 304 may apply an inverse transfer function ITF to the intermediate signal a1(t) in the frequency domain or equivalently in the time domain by anti-phase filtering. Such an inverse transfer function ITF may be generated from a vibration transfer function estimation 310 based on actual vibration measurements of the linear resonant actuator 107 and / or model parameters of the linear resonant actuator 107. The inverse transfer function ITF may be the inverse of a transfer function that relates the output voltage signal VOUT to the actual acceleration of the linear resonant actuator 107. By applying the inverse transfer function ITF to the intermediate signal a1(t), the adjusted anti-phase 304 may generate an inverted vibration signal VINT so that the anti-phase may be applied to a specific target vibration click pulse to obtain an approximation of some desired tactile click signal, thereby driving the vibration actuator to generate a tactile click. In an embodiment where the inverse transfer function ITF is calculated based on the measured values ​​of the linear resonant actuator 107, the processing system 300 can implement a closed-loop feedback system for generating the output signal VOUT, so that the processing system 300 can track the vibration characteristics of the linear resonant actuator 107 throughout the life of the linear resonant actuator 107, thereby enabling more precise control of the tactile response generated by the integrated tactile system 112A.

[0047] In some embodiments, the processing system 300 may not employ an adaptive inverse transfer function ITF, but may apply a fixed inverse transfer function ITF. In other embodiments, the haptic playback waveform a(t) stored in the memory 204 may already include a waveform that has been adjusted by the fixed inverse transfer function ITF, in which case the processing system 300 may not include blocks 302 and 304, and may feed the haptic playback waveform a(t) directly to the click drive pulse processing block 306.

[0048] The click drive pulse processing 306 may receive the inverted vibration signal VINT and control the resonant tail suppression of the inverted vibration signal VINT to generate a processed tactile playback signal VIN. The processing performed by the click drive pulse processing 306 may include, but is not limited to, truncation of the inverted vibration signal VINT, extraction of a minimum phase component of the inverted vibration signal VINT, and / or filtering to control the audibility of the tactile playback signal VIN.

[0049] Comparator 308 may compare a digitized version of force signal VSENSE with a signal threshold VTH associated with a threshold force, and in response to force signal VSENSE exceeding signal threshold VTH, may enable tactile playback signal VIN to be transmitted to amplifier 206 so that amplifier 206 may amplify tactile playback signal VIN to generate output signal VOUT.

[0050] although Figure 3 Comparator 308 is depicted as a simple analog comparator, but in some embodiments, comparator 308 may include a comparator. Figure 3 More detailed logic and / or comparisons are shown, where the enable signal ENABLE output by comparator 308 depends on one or more factors, parameters, and / or other measurements in addition to or in lieu of comparison to a threshold force level.

[0051] In addition, although Figure 3 The enable signal ENABLE is depicted as being transmitted to the click drive pulse processing 306 and selectively enabling / disabling the tactile playback signal VIN, but in other embodiments, the enable signal ENABLE may be transmitted to another component of the processing system 300 (e.g., the vibration pulse processing 302) to enable, disable, or otherwise adjust the output of such other component.

[0052] Figure 4 A block diagram showing selected components of an example integrated haptic system 112B according to an embodiment of the present disclosure. In some embodiments, the integrated haptic system 112B may be used to implement Figure 1 The integrated tactile system 112. Figure 4 As shown, the integrated haptic system 112B may include a digital signal processor (DSP) 402 , an amplifier 406 , an analog-to-digital converter (ADC) 408 , and an ADC 410 .

[0053] DSP 402 may include any system, device, or apparatus configured to interpret and / or execute program instructions and / or process data. In some embodiments, DSP 402 may interpret and / or execute program instructions and / or process data stored in a memory and / or other computer-readable medium accessible to DSP 402. Figure 4As shown, DSP 402 may implement a prototype pitch signal generator 414 , a nonlinear shaping block 416 , a smoothing block 418 , and a speed estimator 420 .

[0054] The prototype tone signal generator 414 may be configured to generate a tone drive signal a(t) at or near the resonant frequency f0 of the linear resonant actuator 107, and monitor the estimated velocity signal VEL generated by the velocity estimator 420 to determine the occurrence of a predetermined threshold level of the estimated velocity signal VEL or the occurrence of a peak of the estimated velocity signal VEL. Upon the occurrence of the predetermined threshold level or peak, the prototype tone signal generator 414 may then cause a change in polarity of the drive signal a(t), which in turn may cause the moving mass of the linear resonant actuator 107 to experience a sudden change in velocity, thereby generating a large acceleration in the linear resonant actuator 107, producing a sharp tactile sensation. The drive signal a(t) generated by the prototype tone signal generator 414 may be followed by a nonlinear shaping block 416, which shapes the waveform drive signal a(t) to more efficiently utilize the drive voltage, and may be further smoothed by a smoothing block 418 to generate an input voltage VIN.

[0055] The speed estimator 420 may be configured to calculate an estimated speed VEL of the linear resonant actuator 107 based on a measured voltage VMON of the linear resonant actuator 107, a measured current IMON of the linear resonant actuator 107, and known characteristics of the linear resonant actuator 107 (e.g., modeling of the speed of the linear resonant actuator 107 as a function of the voltage and current of the linear resonant actuator 107). In some embodiments, one or more other measured values ​​or characteristics associated with the linear resonant actuator 107 (e.g., inductance) may be used in addition to or in lieu of the measured voltage and the measured current to calculate the estimated speed VEL.

[0056] Amplifier 406 may be electrically coupled to DSP 202 and may include any suitable electronic system, device, or apparatus configured to increase the power (e.g., time-varying voltage or current) of input signal VIN to generate output signal VOUT. For example, amplifier 406 may use power from a power supply (e.g., a boost power supply, not explicitly shown) to increase the amplitude of the signal. Amplifier 406 may include any suitable amplifier class, including but not limited to a Class D amplifier.

[0057] ADC 408 may include any suitable system, device, or apparatus configured to convert an analog voltage associated with linear resonant actuator 107 into a digital equivalent measurement voltage signal VMON. Similarly, ADC 410 may include any suitable system, device, or apparatus configured to convert an analog voltage across sense resistor 412 (having a voltage indicative of an analog current associated with linear resonant actuator 107) into a digital equivalent measurement voltage signal IMON.

[0058] In some embodiments, the integrated haptic system 112B may be formed on a single integrated circuit, thereby achieving lower latency compared to existing haptic feedback control methods.

[0059] Figure 5 Graphs depicting example waveforms of tactile drive signals that may be generated according to embodiments of the present disclosure are shown. Figure 5 As shown, the prototype tone signal generator 414 can generate a tone acceleration signal a(t) that starts with a resonant frequency f0 and has a Figure 5 107 ends at a higher frequency than the average frequency f1 shown. This average frequency f1 can be selected as the frequency of the tone that achieves a maximum acceleration level that avoids clipping of the output voltage VOUT. To illustrate, the maximum achievable vibration of the linear resonant actuator 107 can be limited in terms of acceleration. As an example, the linear resonant actuator 107 can be limited by an excursion limit that defines the maximum displacement (e.g., in the positive and negative directions) that the moving mass of the linear resonant actuator 107 can be displaced without contacting a non-moving part of a device that includes the linear resonant actuator 107 or causing audible buzzing and / or clicking distortion.

[0060] Figure 6 Graph showing an example transfer function of displacement of a linear resonant actuator 107 as a function of frequency (x(f)) at a voltage level equal to the maximum static excursion xMAX occurring at low frequencies according to an embodiment of the present disclosure. Figure 6 It is obvious from the graph of that the linear resonant actuator 107 may not be able to tolerate such voltage levels, because at the resonant frequency f0, the excursion x(f) generated by the linear resonant actuator 107 will exceed the static excursion limit xMAX, thereby causing clipping. In this sense, the static excursion limit xMAX can be considered a "no-amplitude" excursion limit.

[0061] Figure 7 Graphs depicting an example transfer function of acceleration of a linear resonant actuator 107 as a function of frequency (a(f)) and maximum acceleration aMAX at maximum excursion xMAX are shown according to embodiments of the present disclosure. In many aspects, Figure 7 yes Figure 6 Conversion from displacement domain to acceleration domain. Figure 7 It can be seen from FIG. 4 that below a certain frequency f1, the maximum acceleration level that can be generated by the linear resonant actuator 107 can be limited by the unclipped excursion limit, rather than by the voltage of the amplifier 406. This means that below a certain frequency f1, the linear resonant actuator 107 needs to be driven at an attenuated voltage level. On the other hand, for a maximum voltage level that almost reaches the maximum excursion limit xMAX without clipping, the maximum achievable unclipped acceleration level aMAX can be reached not at the resonant frequency f0 but at a selected frequency f1 above resonance.

[0062] The selected frequency f1 can be designed for tactile clicks and the timing of the polarity change of the acceleration signal a(t) (e.g., the elapsed time T1, such as Figure 3 ) provides a good initialization option to reach the peak acceleration. However, in addition to the specific example of a very short pulse described above, other examples of waveforms with longer periods can be used, as well as other logic to determine the elapsed time T1 (e.g., time T1) to change the polarity of the acceleration signal a(t), which has the effect of forcing the moving mass to change speed quickly and generate a larger acceleration peak. The greater the rate of change of speed, the higher the acceleration peak that the linear resonant actuator 107 can produce.

[0063] Figure 8 A block diagram showing selected components of another example integrated haptic system 112C according to an embodiment of the present disclosure. In some embodiments, the integrated haptic system 112C may be used to implement Figure 1 The integrated tactile system 112. Figure 8 As shown, the integrated haptic system 112C may include a detector 808 and an amplifier 806 .

[0064] Detector 808 may include any system, device, or apparatus configured to detect a signal (e.g., VSENSE) indicating a force. In some embodiments, such a signal may be a signal generated by a force sensor. In other embodiments, this signal may include a GPIO signal indicating the force applied to the force sensor. In some embodiments, detector 808 may simply detect whether the GPIO signal is valid or invalid. In other embodiments, signal VSENSE may indicate the magnitude of the force applied and logic may be applied (e.g., analog-to-digital conversion of an analog signal, comparison with a threshold force level, and / or logic associated with other measurements or parameters). In any case, in response to signal VSENSE indicating the necessary force, detector 808 may enable amplifier 806 (e.g., by enabling its power supply or power boost mode) so that amplifier 806 may amplify haptic playback signal VIN (which may be generated by components internal or external to integrated haptic system 112C) to generate output signal VOUT. Thus, amplifier 806 may remain in a low power or inactive state until integrated haptic system 112C receives the necessary input signal, at which time the amplifier may be powered or effectively turned on. Allowing the amplifier 806 to remain in a low-power or inactive state until the necessary input is received can significantly reduce the power consumption of the circuit and enable “always on” functionality for devices including the integrated haptic system 112C.

[0065] In an alternative embodiment, the detector 808 may be configured to enable the haptic playback signal VIN to be transmitted to the amplifier 806 in response to the necessary signal VSENSE, so that the amplifier 806 may amplify the haptic playback signal VIN to generate the output signal VOUT.

[0066] In some embodiments, all or a portion of detector 808 may be implemented by a DSP.

[0067] Amplifier 806 may be electrically coupled to detector 808 and may include any suitable electronic system, device, or apparatus configured to increase the power (e.g., time-varying voltage or current) of input signal VIN to generate output signal VOUT. For example, amplifier 806 may use power from a power supply (not explicitly shown) to increase the amplitude of the signal. Amplifier 806 may include any suitable amplifier class, including but not limited to a Class D amplifier.

[0068] In some embodiments, the integrated haptic system 112C may be formed on a single integrated circuit, thereby achieving lower latency compared to existing haptic feedback control methods.

[0069] Fig. 9 A block diagram showing selected components of an example integrated haptic system 112D according to an embodiment of the present disclosure. In some embodiments, the integrated haptic system 112D may be used to implement Figure 1 The integrated tactile system 112. Fig. 9 As shown, the integrated haptic system 112D may include a digital signal processor (DSP) 902 , an amplifier 906 , and an application processor interface 908 .

[0070] DSP 902 may include any system, device or apparatus configured to interpret and / or execute program instructions and / or process data. In some embodiments, DSP 902 may interpret and / or execute program instructions and / or process data stored in memory and / or other computer-readable media accessible to DSP 902.

[0071] Amplifier 906 may be electrically coupled to DSP 902 and may include any suitable electronic system, device, or apparatus configured to increase the power (e.g., time-varying voltage or current) of input signal VIN to generate output signal VOUT. For example, amplifier 906 may use power from a power supply (not explicitly shown) to increase the amplitude of the signal. Amplifier 906 may include any suitable amplifier class, including but not limited to a Class D amplifier.

[0072] The application processor interface 908 may be communicatively coupled to the DSP 902 and an application processor external to the integrated haptic system 112D (eg, Figure 1 Thus, the application processor interface 908 may enable communication between the integrated haptic system 112D and an application executing on the application processor.

[0073] In some embodiments, the integrated haptic system 112D may be formed on a single integrated circuit, thereby achieving lower latency compared to existing haptic feedback control methods.

[0074] In operation, DSP 902 may be configured to receive force signal VSENSE from force sensor 105 indicating a force applied to force sensor 105. In response to receiving force signal VSENSE indicating a sensed force, DSP 902 may generate haptic playback signal VIN and transmit haptic playback signal VIN to amplifier 906. Additionally, in response to receiving force signal VSENSE indicating a sensed force, DSP 902 may transmit an activity notification to an appropriate application processor via application processor interface 908. DSP 902 may be further configured to receive communications from an application processor via application processor interface 908 and generate haptic playback signal VIN (in addition to or in lieu of generating in response to receiving force signal VSENSE), and transmit haptic playback signal VIN to amplifier 906.

[0075] Since the output for the initial tactile feedback response can be generated by the integrated tactile system 112D, the integrated tactile system 112D can be configured to provide a low-latency response time for generating immediate tactile feedback. After the initial feedback is generated, the control of the additional tactile feedback signal can be determined by a separate application processor arranged to engage with the integrated tactile system 112D. By unloading the control of the subsequent tactile driver signal to a separate application processor, the integrated tactile system 112D can be optimized for low-power, low-latency performance to generate an initial tactile feedback response. The initial output signal VOUT can be provided at a relatively low resolution, resulting in the generation of a relatively simplified tactile feedback response. For example, the initial output signal VOUT can be provided as a global feedback response. After the initial response, the application processor can be used to generate a more detailed tactile feedback output, such as providing a local tactile feedback response, which may require increased processing resources compared to the relatively direct generation of a global tactile feedback response.

[0076] As another example, to minimize power consumption of the mobile device 102 for always-on operation, the integrated haptic system 112D can be configured to monitor a single input from a single force sensing transducer (e.g., force sensor 105) to detect user input. However, once the initial user input is detected, the capabilities and resources of the application processor can be used to provide a more detailed signal analysis and response. The application processor can be configured to receive input signals from multiple force sensing transducers and / or generate output signals for multiple tactile transducers.

[0077] Fig.10 A block diagram showing selected components of an example integrated haptic system 112E according to an embodiment of the present disclosure. In some embodiments, the integrated haptic system 112E may be used to implement Figure 1 The integrated tactile system 112. Fig.10 As shown, the integrated haptic system 112E may include a digital signal processor (DSP) 1002 , an amplifier 1006 , and a signal combiner 1008 .

[0078] DSP 1002 may include any system, device or apparatus configured to interpret and / or execute program instructions and / or process data. In some embodiments, DSP 1002 may interpret and / or execute program instructions and / or process data stored in memory and / or other computer-readable media accessible to DSP 1002.

[0079] Amplifier 1006 may be electrically coupled to DSP 1002 (e.g., via signal combiner 1008) and may include any suitable electronic system, device, or apparatus configured to increase the power (e.g., time-varying voltage or current) of input signal VIN to generate output signal VOUT. For example, amplifier 1006 may use power from a power supply (not explicitly shown) to increase the amplitude of the signal. Amplifier 1006 may include any suitable amplifier class, including but not limited to a Class D amplifier.

[0080] The signal combiner 1008 may be coupled between the DSP 1002 and the amplifier 1006 and may include any system, device, or apparatus configured to combine the signal generated by the DSP 1002 and the vibration alert signal received from a component external to the integrated haptic system 112E.

[0081] In some embodiments, the integrated haptic system 112E may be formed on a single integrated circuit, thereby achieving lower latency compared to existing haptic feedback control methods.

[0082] In operation, DSP 1002 may be configured to receive a force signal VSENSE from force sensor 105 indicating a force applied to force sensor 105. In response to receiving the force signal VSENSE indicating the sensed force, DSP 1002 may generate an intermediate haptic playback signal VINT. Signal combiner 1008 may receive the intermediate haptic playback signal VINT and mix the intermediate haptic playback signal VINT with another signal (e.g., a vibration alert signal) received by integrated haptic system 112E to generate a haptic playback signal VIN and transmit the haptic playback signal VIN to amplifier 1006. Thus, a haptic signal (e.g., intermediate haptic playback signal VINT) generated in response to a force may be mixed with another signal (e.g., a vibration alert signal) to provide a composite signal (e.g., haptic playback signal VIN) for linear resonant actuator 107. For example, a signal for generating a pure haptic feedback response may be mixed with a signal for generating a vibration notification or alert (e.g., as a notification of an incoming call or message). Such a mix would allow the user to determine that an alert has been received while feeling a tactile feedback response. Fig.10 As shown, the signal combiner 1008 may mix input signals for use as inputs to the amplifier 1006. However, in other embodiments, the signal combiner may mix output signals for driving the linear resonant actuator 107.

[0083] Fig.11 A block diagram showing selected components of an example integrated haptic system 112F according to an embodiment of the present disclosure. In some embodiments, the integrated haptic system 112F may be used to implement Figure 1 The integrated tactile system 112. Fig.11 As shown, the integrated haptic system 112F may include a digital signal processor (DSP) 1102 , a detector 1104 , an amplifier 1106 , a sampling control 1108 , and a sensor bias generator 1112 .

[0084] DSP 1102 may include any system, device or apparatus configured to interpret and / or execute program instructions and / or process data. In some embodiments, DSP 1102 may interpret and / or execute program instructions and / or process data stored in memory and / or other computer-readable media accessible to DSP 1102.

[0085] Detector 1104 may include any system, device, or apparatus configured to detect a signal (e.g., VSENSE) indicating a force. In some embodiments, this signal may be a signal generated by a force sensor. In other embodiments, this signal may include a GPIO signal indicating the force applied to the force sensor. In some embodiments, detector 1104 may simply detect whether the GPIO signal is valid or invalid. In other embodiments, signal VSENSE may indicate the magnitude of the applied force and logic may be applied (e.g., analog-to-digital conversion of an analog signal, comparison with a threshold force level, and / or logic associated with other measurements or parameters). In any case, in response to signal VSENSE indicating the necessary force, detector 1104 may transmit one or more signals indicating signal VSENSE to DSP 1102. In some embodiments, all or a portion of detector 1104 may be implemented by DSP 1102.

[0086] Amplifier 1106 may be electrically coupled to DSP 1102 and may include any suitable electronic system, device, or apparatus configured to increase the power (e.g., a voltage or current that varies over time) of an input signal VIN to generate an output signal VOUT. For example, amplifier 1106 may use power from a power supply (not explicitly shown) to increase the amplitude of the signal. Amplifier 1106 may include any suitable amplifier class, including but not limited to a Class D amplifier.

[0087] The sampling control 1108 may be communicatively coupled to the DSP 1102 and may include any suitable electronic system, device, or apparatus configured to selectively enable components of the force sensor 105 and / or the integrated haptic system 112F, as described in greater detail below.

[0088] The sensor bias 1112 may be communicatively coupled to the sampling control 1108 and may include any suitable electronic system, device, or apparatus configured to generate an electrical bias (eg, a bias voltage or a bias current) for the force sensor 105 , as described in greater detail below.

[0089] In some embodiments, the integrated haptic system 112F may be formed on a single integrated circuit, thereby achieving lower latency compared to existing haptic feedback control methods.

[0090] In operation, DSP 1102 / detector 1104 may be configured to receive a force signal VSENSE from force sensor 105 indicating a force applied to force sensor 105. In response to receiving the force signal VSENSE indicating the sensed force, DSP 1102 may generate a haptic playback signal VIN and transmit the haptic playback signal VIN to amplifier 1106, which amplifies the haptic playback signal VIN to generate an output voltage VOUT.

[0091] Additionally, the DSP 1102 may be configured to receive one or more timer signals (from timing signals generated within the integrated haptic system 112F or external to the integrated haptic system 112F) and, based thereon, generate signals to the sampling control 1108. The sampling control 1108 may then selectively enable and disable one or more components of an input path of the integrated haptic system 112F, including but not limited to the detector 1104, the force sensor 105, a data interface of the integrated haptic system 112F, a switch matrix of the integrated haptic system 112F, an input amplifier of the integrated haptic system 112F, and / or an analog-to-digital converter of the integrated haptic system 112F. Fig.11 As shown, the sampling control 1108 can selectively enable and disable the force sensor 105 by controlling the electrical bias for the force sensor 105 generated by the sensor bias 1112. Thus, the DSP 1102 and the sampling control 1108 can modulate the duty cycle duration at which the force sensor 105, the detector 1104, and / or other components of the integrated haptic system 112F are active, thereby potentially reducing power consumption of a system including the integrated haptic system 112F.

[0092] Although the foregoing figures and description thereof present the integrated haptic systems 112A- 112F as representative of particular embodiments, it should be understood that all portions of one or more of the integrated haptic systems 112A- 112F may be appropriately combined with all or a portion of another.

[0093] Additionally, in many of the above figures, the DSP is shown generating a haptic playback signal VIN, which is amplified by an amplifier to generate an output voltage VOUT. For purposes of clarity and illustration, digital-to-analog conversion of signals in the output signal paths of the integrated haptic systems 112A-112F is omitted from the figures, but it should be understood that a digital-to-analog converter may be present in the integrated haptic systems 112A-112F to perform any necessary conversion from the digital domain to the analog domain.

[0094] The present disclosure includes all changes, substitutions, variations, changes and modifications to the exemplary embodiments herein that would be understood by a person of ordinary skill in the art. Similarly, the appended claims include all changes, substitutions, variations, changes and modifications to the exemplary embodiments herein that would be understood by a person of ordinary skill in the art, where appropriate. In addition, a reference in the appended claims to a device or system or a component of a device or system that is adapted, arranged, capable, configured, enabled, operable or operative to perform a specific function includes the device, system or component, regardless of whether it or the specific function is activated, turned on or unlocked, as long as the device, system or component is so adapted, arranged, capable, configured, enabled, operable or operative.

[0095] All examples and conditional language described herein are intended to help readers understand the present invention and the concepts provided by the inventors for further developing the field, and are interpreted as not being limited to these specific narrated examples and conditions. Although embodiments of the present invention have been described in detail, it should be understood that various changes, substitutions and variations may be made thereto without departing from the spirit and scope of the present invention.

Claims

1. An integrated tactile system, characterized in that: include: A digital signal processor, the digital signal processor being configured to: receiving an input signal indicative of a force applied to the force sensor; as well as generating a haptic playback signal in response to the input signal; Generating a tactile playback signal includes: retrieving a haptic playback waveform from a memory communicatively coupled to the digital signal processor; and the digital signal processor applying an inverse transfer function to the haptic playback waveform to generate the haptic playback signal, wherein the inverse transfer function is an inverse of a transfer function defining a relationship between a voltage applied to a vibration actuator and an acceleration of the vibration actuator in response to the applied voltage; an amplifier communicatively coupled to the digital signal processor, integrated into the integrated haptic system with the digital signal processor, and configured to amplify the haptic playback signal and drive a vibration actuator communicatively coupled to the amplifier using the haptic playback signal amplified by the amplifier; Wherein, the digital signal processor is further configured as: monitoring one or more diagnostic inputs indicative of a status of the vibration actuator; determining a displacement of the vibration actuator based on the one or more diagnostic inputs; controlling the haptic playback signal to prevent the vibration actuator from exceeding a displacement limit; and The polarity of the haptic playback signal is changed in response to a condition for changing the polarity of the haptic playback signal.

2. The integrated tactile system according to claim 1, characterized in that The haptic playback waveform is acceleration as a function of time.

3. The integrated tactile system according to claim 2, characterized in that The digital signal processor generates the haptic playback signal to present haptic feedback for at least one of mechanical button replacement and capacitive sensor feedback.

4. The integrated tactile system according to claim 1, characterized in that The digital signal processor controls the haptic playback signal in a closed-loop feedback loop, whereby the digital signal processor adapts the inverse transfer function based on at least one of a modeled parameter and a measured parameter of the vibration actuator.

5. The integrated tactile system according to claim 1, characterized in that The digital signal processor controls the haptic playback signal in a closed-loop feedback loop, whereby the digital signal processor adapts the inverse transfer function based on at least one of a modeled parameter and a measured parameter of the vibration actuator.

6. The integrated tactile system according to claim 1, characterized in that The input signal is a force sensor signal generated by the force sensor; and In response to receipt of the force sensor signal, the digital signal processor transmits the haptic playback signal to the amplifier.

7. The integrated tactile system according to claim 1, characterized in that The input is a force sensor signal generated by the force sensor; and In response to the force sensor signal exceeding a threshold, the digital signal processor transmits the haptic playback signal to the amplifier.

8. The integrated tactile system according to claim 1, characterized in that The digital signal processor generates the haptic playback signal to present haptic feedback for at least one of mechanical button replacement and capacitive sensor feedback.

9. The integrated tactile system according to claim 1, characterized in that: The digital signal processor is further configured to calculate an estimated velocity based on one or more measured electrical parameters of the vibration actuator, wherein the condition for changing the polarity of the haptic playback signal includes the estimated velocity reaching a threshold velocity level or a velocity peak.

10. The integrated tactile system according to claim 9, characterized in that The electrical parameters measured include one or more of voltage and current.

11. The integrated tactile system according to claim 1, characterized in that The condition for changing the polarity of the haptic playback signal includes an elapsed time equal to the inverse of a frequency at which a maximum unclipped acceleration level is achievable.

12. The integrated tactile system according to claim 1, characterized in that The one or more diagnostic inputs are indicative of one or more of a current, a voltage, and an inductance of the vibration actuator.

13. The integrated tactile system according to claim 1, characterized in that Also included is an application processor interface coupled between the digital signal processor and an application processor external to the integrated haptic system, wherein the digital signal processor is further configured to communicate information to the application processor via the application processor interface in response to the force.

14. The integrated tactile system according to claim 1, characterized in that Also included is an application processor interface coupled between the digital signal processor and an application processor external to the integrated haptic system, wherein the digital signal processor is further configured to: receiving a communication from the application processor via the application processor interface; and The haptic playback signal is modified in response to the communication.

15. The integrated tactile system according to claim 1, characterized in that The integrated haptic system is further configured to mix the intermediate haptic playback signal generated by the digital signal processor with another signal received by the integrated haptic system to generate the haptic playback signal.

16. The integrated tactile system of claim 1, wherein: The digital signal processor is also configured to selectively enable and disable the amplifier based on the input signal.

17. The integrated haptic system of claim 1, wherein: The integrated haptic system is integrated with one of a mobile phone, a personal digital assistant, and a game controller.

18. The integrated haptic system of claim 1, wherein: The digital signal processor and the amplifier are integrated on a single integrated circuit.

19. A tactile feedback control method, characterized in that: include: receiving, by a digital signal processor, an input signal indicative of a force applied to the force sensor; generating, by the digital signal processor, a haptic playback signal in response to the input signal; Generating a tactile playback signal includes: retrieving a haptic playback waveform from a memory communicatively coupled to the digital signal processor; and The digital signal processor applies an inverse transfer function to the haptic playback waveform to generate the haptic playback signal, wherein the inverse transfer function is an inverse of a transfer function defining a relationship between a voltage applied to a vibration actuator and an acceleration of the vibration actuator in response to the applied voltage; and amplifying the haptic playback signal with an amplifier communicatively coupled to the digital signal processor and integrated with the digital signal processor into an integrated haptic system; monitoring, by the digital signal processor, one or more diagnostic inputs indicative of a status of a vibration actuator; and determining, by the digital signal processor, a displacement of the vibration actuator based on the one or more diagnostic inputs; and controlling the tactile playback signal by the digital signal processor to prevent the vibration actuator from exceeding a displacement limit; The polarity of the haptic playback signal is changed by the digital signal processor in response to a condition for changing the polarity of the haptic playback signal.

20. The method according to claim 19, characterized in that The haptic playback waveform is acceleration as a function of time.

21. The tactile feedback control method according to claim 20, characterized in that: The digital signal processor generates the haptic playback signal to present haptic feedback for at least one of mechanical button replacement and capacitive sensor feedback.

22. The tactile feedback control method according to claim 21, characterized in that: The haptic playback signal is controlled by the digital signal processor in a closed-loop feedback loop, whereby the digital signal processor adapts the inverse transfer function based on at least one of a modeled parameter and a measured parameter of the vibration actuator.

23. The tactile feedback control method according to claim 19, characterized in that: The input signal is a force sensor signal generated by the force sensor; and The method also includes transmitting, by the digital signal processor, the haptic playback signal to the amplifier in response to receipt of the force sensor signal.

24. The tactile feedback control method according to claim 19, characterized in that: The input signal is a force sensor signal generated by the force sensor; and The method also includes transmitting, by the digital signal processor, the haptic playback signal to the amplifier in response to the force sensor signal exceeding a threshold.

25. The tactile feedback control method according to claim 19, characterized in that: The digital signal processor generates the haptic playback signal to present haptic feedback for at least one of mechanical button replacement and capacitive sensor feedback.

26. The tactile feedback control method according to claim 19, characterized in that: Also includes: The haptic playback signal is controlled by the digital signal processor in a closed-loop feedback loop, whereby the digital signal processor adapts its processing based on at least one of a modeled parameter and a measured parameter of a vibration actuator.

27. The tactile feedback control method according to claim 19, characterized in that: An estimated velocity is calculated by the digital signal processor based on one or more measured electrical parameters of a vibration actuator, wherein the condition for changing the polarity of the haptic playback signal includes the estimated velocity reaching a threshold velocity level or a velocity peak.

28. The tactile feedback control method according to claim 27, characterized in that: The measured electrical parameters include one or more of voltage and current.

29. The tactile feedback control method according to claim 27, characterized in that: The condition for changing the polarity of the haptic playback signal includes an elapsed time equal to the inverse of a frequency at which a maximum unclipped acceleration level is achievable.

30. The tactile feedback control method according to claim 19, characterized in that: The one or more diagnostic inputs are indicative of one or more of a current, a voltage, and an inductance of the vibration actuator.

31. The tactile feedback control method according to claim 19, characterized in that: The method further includes transmitting information by the digital signal processor to an application processor outside the integrated haptic system via an application processor interface in response to the force, wherein the application processor interface is coupled between the digital signal processor and the application processor.

32. The tactile feedback control method according to claim 19, characterized in that: receiving communications from an application processor external to the integrated haptic system via an application processor interface, wherein the application processor interface is interfaced between the digital signal processor and the application processor; and The haptic playback signal is modified in response to the communication.

33. The tactile feedback control method according to claim 19, characterized in that: An intermediate haptic playback signal generated by the digital signal processor is mixed with another signal received by the integrated haptic system to generate the haptic playback signal.

34. The tactile feedback control method according to claim 19, characterized in that: Also includes: The amplifier is selectively enabled and disabled based on the input signal.

35. The tactile feedback control method according to claim 19, characterized in that: The digital signal processor and the amplifier are integrated on a single integrated circuit.

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