Adaptive analog-to-digital converter (ADC) multi-path digital microphone

Abstract

The example multi-path digital microphones described in this application can include example embodiments of adaptive ADC range multi-path digital microphones that allow for low power for the amplifier or gain stage and example adaptive ADCs in the example multi-path digital microphone arrangements described herein while still providing a high DR digital microphone system. Additional non-limiting embodiments can include example glitch removal components configured to minimize audible artifacts associated with changes in gain for the example adaptive ADCs.

Description

[0001] CLAIM OF PRIORITY

[0002] This patent application claims priority to U.S. Provisional Patent Application Serial No. 62 / 769, 139, filed November 19, 2018, entitled “ARCHITECTURE PROPOSAL: ADAPTIVE ADC RANGE WITH TWO PATH,” and U.S. Non-Provisional Application Serial No. 16 / 673,484, filed November 4, 2019, entitled “ADAPTIVE ANALOG TO DIGITAL CONVERTER (ADC) MULTIPATH DIGITAL MICROPHONES,” the entire contents of each application are incorporated herein by reference. TECHNICAL FIELD

[0003] This application relates to digital microphones, and more particularly to multi-path digital microphone implementations. BACKGROUND

[0004] Microphones can be exposed to environments where the sound level (described using the sound pressure level in decibels on a log scale (dBSPL)) can vary from very quiet (e.g., less than 25 dB SPL) to very loud (e.g., 140 dB SPL). Moreover, microphones are often required to maintain their performance over a large signal range (e.g., up to 120 dB). At the same time, microphones need to exhibit very small intrinsic noise so that weak audio signals can be detected, while they also need to handle large audio signals without significant distortion. Therefore, such requirements dictate that microphones have a very large dynamic range (DR).

[0005] Analog and digital microphones output a voltage or a digital output stream, respectively, corresponding to the audio signal sensed by the microphone. The advantage of a digital microphone is that its digital output stream is relatively immune to noise, and the analog-to-digital converter (ADC) does not need to perform digital signal processing on the microphone digital output stream. One disadvantage of a digital microphone, however, is that its dynamic range is often lower than what is achievable with an analog microphone due to the limitations on the power consumption that can be allocated to the microphone in many applications.

[0006] Conventional solutions for boosting the DR of a digital microphone can include techniques such as employing one or more high-DR ADCs or employing an automatic gain control amplifier (AGC), which can significantly reduce the ADC DR requirements while still meeting the desired maximum SPL and noise floor levels of the overall digital microphone. However, such conventional solutions can require excessive power consumption and / or introduce undesirable artifacts. Other solutions can require a specific analog front end (which can be affected by low signal-to-noise ratio (SNR) performance) or a multi-path approach (which can be affected by transient saturation effects due to the combining algorithm).

[0007] Furthermore, it is desirable to implement the ability to integrate a high-DR digital microphone in devices (e.g., mobile devices) that can be exposed to a wide variety of varying SPL environments. For example, a digital microphone that includes one or more micro-electro-mechanical system (MEMS) acoustic sensors with components that implement a high-DR algorithm in a complementary metal-oxide-semiconductor (CMOS) process can provide a low-power, high-DR digital microphone suitable for such mobile devices. However, as the demand for consumer electronics trends toward smaller, mobile, and more feature-rich devices, the demand for high-DR, digital, feature-rich microphones continues to face the ongoing demand for smaller and more power-conserving devices. Thus, a low-power, high-DR ADC remains a challenge for providing a high-DR, feature-rich, and low-power compact digital microphone.

[0008] Accordingly, it is desirable to provide a high dynamic range digital microphone that ameliorates these and / or other drawbacks. The above-described shortcomings are merely provided as a summary of some problems of conventional implementations and are not intended to be exhaustive. Other problems with conventional implementations and techniques, and corresponding benefits of the various aspects described herein, can become further apparent upon review of the following description. SUMMARY

[0009] The following provides a simplified summary of the present specification to provide a basic understanding of some aspects of the present specification. This summary is not an extensive overview of the present specification. It is not intended to identify key or critical elements of the present specification or to delineate the scope of any embodiments of the present specification or any scope of the claims. Its sole purpose is to present some simplified concepts of the present specification in a simplified format as a prelude to the more detailed description provided later.

[0010] In one non-limiting example, an example multi-path digital microphone is described. The example multi-path digital microphone described herein can include an example embodiment of an adaptive ADC range multi-path digital microphone that allows for a low power amplifier or gain stage and an example adaptive ADC in the example multi-path digital microphone arrangement described herein while still providing a high-DR (dynamic range) digital microphone system.

[0011] Accordingly, example multi-path digital microphones can include a plurality of digital audio filters respectively operatively coupled to an example adaptive analog-to-digital converter (ADC) configured to receive digital audio signals having different scaling factors associated with respective audio signals and configured to provide one or more filtered digital audio signals. Moreover, example multi-path digital microphone systems can include an example ADC range control component configured to adjust a gain of the example adaptive ADC based on respective sound pressure level thresholds sensed in the one or more filtered digital audio signals. Also, example multi-path digital microphone systems can include one or more gain compensation components respectively associated with the one or more filtered digital audio signals, wherein the example ADC range control component is further configured to continuously adjust a gain of the one or more gain compensation components to compensate for changes in the gain of the example adaptive ADC. Additional non-limiting embodiments can include an example glitch removal component configured to minimize audible artifacts associated with the changes in the gain of the example adaptive ADC. In another non-limiting aspect, example systems can also include an output component configured to transmit digital signals associated with the digital MEMS microphone, including one or more pulse-density modulation (PDM) signals, integrated interchip sound (I2S) signals, or Soundwire signals. 2 S) signals or Soundwire signals.

[0012] In another non-limiting aspect, example methods and systems are described in association with multi-path digital microphone systems.

[0013] These and other embodiments are described in detail below. BRIEF DESCRIPTION OF DRAWINGS

[0014] Various non-limiting embodiments are further described in detail below with reference to the attached drawings.

[0015] Figure 1 shows a functional block diagram of an example digital microphone system including a two-path digital audio combiner component in accordance with an aspect of the present application;

[0016] Figure 2 shows a functional block diagram of an example digital microphone system including a two-path digital audio combiner component in accordance with an aspect of the present application;

[0017] Figure 3 shows a functional block diagram of an example low-power gain stage in accordance with another non-limiting aspect of the present application;

[0018] Figure 4 shows a functional block diagram of an example implementation of an adaptive analog-to-digital converter (ADC) in accordance with another non-limiting aspect of the present application;

[0019] Figure 5 Another functional block diagram showing an example aspect of an adaptive ADC in accordance with another non-limiting aspect of the present application;

[0020] Figure 6 A functional block diagram showing an example aspect of an adaptive ADC range multi-path digital microphone system in accordance with a non-limiting aspect of the present application;

[0021] Figure 7 Another functional block diagram showing an example aspect of an adaptive ADC range multi-path digital microphone system in accordance with another non-limiting aspect of the present application;

[0022] Figure 8 Another functional block diagram showing an example aspect of an adaptive ADC range multi-path digital microphone system in accordance with another non-limiting aspect of the present application;

[0023] Figure 9 A non-limiting state diagram showing an example digital microphone system including a non-limiting implementation of an adaptive ADC configured with a two-path digital audio combiner component in accordance with another aspect of the present application;

[0024] Figure 10 A functional block diagram showing an example aspect of an adaptive ADC range multi-path digital microphone system in accordance with a non-limiting aspect of the present application;

[0025] Figure 11 Another functional block diagram showing an example aspect of an adaptive ADC range multi-path digital microphone system in accordance with another non-limiting aspect of the present application;

[0026] Figure 12 A functional block diagram showing an example aspect of an adaptive ADC range multi-path digital microphone in accordance with a non-limiting aspect of the present application;

[0027] Figure 13 An example flow diagram showing a non-limiting method associated with various non-limiting embodiments of the present application; and

[0028] Figure 14 Another example flow diagram showing another non-limiting method associated with various non-limiting embodiments of the present application. DETAILED DESCRIPTION

[0029] While a brief summary has been provided, for purposes of illustrating the application, not limitation, particular aspects of the present application are described herein using various non-limiting examples. It should be understood that variations and modifications of the devices and techniques described herein are possible and are within the scope of the subject matter disclosed herein.

[0030] In accordance with various described embodiments, the present application provides digital microphones, systems, and methods for multipath digital microphones. In non-limiting aspects, example embodiments can include MEMS digital sensors that employ an adaptive analog-to-digital conversion in the sensor signal path. As used herein, the term adaptive ADC and the like can be understood to refer to one or more components that can be configured to operate on the ADC from input to output and / or facilitate a variable scaling factor (e.g., through a variable sampling capacitor or other component of the ADC, etc.) to allow the range or gain of the ADC to be changed depending on the context. For example, in some non-limiting examples described herein, an adaptive ADC can refer to an ADC (e.g., a Sigma Delta modulator, etc.) in combination with a filter (e.g., a low pass filter, an integer decimator, etc.) that facilitates a variable scaling factor on the ADC from input to output (e.g., through a variable sampling capacitor or other component of the ADC, etc.) to allow the range or gain of the ADC to be changed. In other non-limiting examples, an adaptive ADC can refer to one or more other components (e.g., a successive approximation ADC, etc.) that facilitate a variable scaling factor on the ADC from input to output to allow the range or gain of the ADC to be changed. As described above, a digital microphone outputs a digital output stream corresponding to an audio signal sensed by the microphone. While digital microphones are relatively immune to noise and do not require an ADC on their output stream, the dynamic range can be lower than what is achievable with an analog microphone under the power consumption constraints of the microphone for a particular application. As the demand for consumer electronics trends towards smaller, mobile, and more feature-rich devices, the demand for high-DR, digital, and more feature-rich microphones continues to face the ongoing demand for smaller and more power-conserving devices.

[0031] Figure 1A functional block diagram showing an example operating environment 100 suitable for including various non-limiting aspects of the present application is shown. As a non-limiting example, the example operating environment 100 can include one or more example micro- electro-mechanical system (MEMS) acoustic or microphone sensors 102 (e.g., one or more MEMS acoustic or microphone sensors, etc.). In various embodiments, the example system is shown as including one MEMS acoustic or microphone sensor 102, although other example systems can be described as including more than one MEMS acoustic or microphone sensor 102. It can be appreciated that various MEMS acoustic or microphone sensors 102 need not be identical in design, manufacture, characteristics, and / or arrangement, etc., and one or more example MEMS acoustic or microphone sensors 102 can differ in one or more of the foregoing aspects, depending on the non-limiting aspect. In one non-limiting aspect, one or more MEMS acoustic or microphone sensors 102 can be configured to receive one or more acoustic signals or variations associated therewith (e.g., acoustic signals that vary as a result of differences in time, location, acoustic path, etc.) or can be comprised of any number of different transducer structures (e.g., number and / or configuration of membranes, etc.), any number of front-end circuit designs (e.g., supply variable charge pump voltage, etc.), etc.

[0032] One or more MEMS acoustic or microphone sensors 102 can be configured to receive one or more acoustic signals and can be operatively coupled to one or more components or circuits 104 (e.g., one or more components or circuits 104, sometimes referred to herein as "front-ends"), which are configured to process one or more electrical signals that vary in dependence on the one or more acoustic signals (e.g., one or more electrical signals associated with one or more MEMS acoustic or microphone sensors, etc.) to create one or more corresponding processed electrical signals (e.g., one or more outputs of one or more components or circuits 104, etc.).

[0033] In another non-limiting example, the example operating environment 100 can include one or more example amplifier or gain stages 106 (e.g., one or more amplifier or gain stages 106, etc.), which can be operatively coupled to the one or more outputs associated with one or more components or circuits 104 (e.g., one or more components or circuits 104, etc.). In one non-limiting aspect, one or more amplifier or gain stages 106 can be configured to receive the one or more corresponding processed electrical signals and / or to apply one or more scaling factors (e.g., one or more analog scaling factors) to the one or more corresponding processed electrical signals, for example, as described herein with respect to Figures 3-4 Further described.

[0034] In addition, the example operating environment 100 may also include one or more example ADCs 108 (e.g., one or more adaptive ADCs, etc.) operably coupled to one or more outputs associated with one or more amplifiers or gain stages 106, as described herein. Figures 4-5 Further, in another non-limiting embodiment, one or more example ADCs 108 may be configured to provide one or more digital audio signals having different digital scaling factors associated with the one or more acoustic signals (e.g., outputs associated with one or more ADCs 108, etc.). In another non-limiting embodiment, one or more components or circuits 104 may include one or more adjustable DC bias voltage circuits or associated with one or more adjustable DC bias voltage circuits operatively coupled to one or more MEMS acoustic or microphone sensors 102, and the one or more components or circuits 104 may be configured to adjust one or more DC bias voltages respectively provided to one or more MEMS acoustic or microphone sensors 102, for example, via one or more charge pumps 110.

[0035] like Figure 1 As shown, it can be understood that the noise in the sampling RC circuit is limited by kT / C noise, for example, caused by the capacitors associated with one or more ADCs 108. It can also be understood that the ADC (e.g., one or more ADCs 108) is a significant power-consuming element. To obtain a high dynamic range (e.g., maximum signal-to-noise ratio) ADC (e.g., a dynamic range of 91 dB 112), assuming kT / C noise is dominant, it can be expected that for every doubling of the dynamic range, the power consumption increases by approximately four times. Therefore, it can be demonstrated that simply designing an ADC with a large dynamic range may result in unacceptably high power consumption.

[0036] Figure 2 This illustration shows a functional block diagram of an example digital microphone system 200, including a dual-path digital audio combiner component, according to a non-limiting implementation of this application. U.S. Patent No. 9,673,768 describes a multipath digital microphone system including a multipath digital audio combiner component, the entire contents of which are incorporated herein by reference. As a non-limiting example, Figure 2 This diagram shows a functional block diagram of an example digital microphone system 200, including a dual-path digital audio combiner component 210, according to a non-limiting implementation of this application. For example, as shown above... Figure 1The example digital microphone system 200 can include one or more example MEMS acoustic or microphone sensors 102 (e.g., one or more MEMS acoustic or microphone sensors 102, etc.) operably coupled to one or more components or circuits 104 (e.g., one or more components or circuits 104, etc.), or front-ends, one or more example amplifiers or gain stages 106 (e.g., one or more amplifiers or gain stages 106, etc.) operably coupled to one or more outputs associated with the one or more components or circuits 104 (e.g., one or more components or circuits 104, etc.), one or more example ADCs 108 (e.g., one or more ADCs 108, etc.) operably coupled to one or more outputs associated with the one or more amplifiers or gain stages 106. In addition, the example digital microphone system 200 can also include an example multi-path digital audio combiner component 210 operably coupled to one or more outputs associated with the one or more ADCs 108 (e.g., outputs associated with the one or more ADCs 108, etc.).

[0037] As Figure 2 another non-limiting example in FIG. 2, the example digital microphone system 200 is shown as a digital dual-path microphone system that can employ a single MEMS acoustic or microphone sensor 102 and a single front-end 104 that couples a low-SPL path (e.g., including an example amplifier or gain stage 202 and an example ADC 206) and a high-SPL path (e.g., including an example amplifier or gain stage 204 and an example ADC 208), the outputs of the example ADC 206 and ADC 208 being coupled to an example multi-path digital audio combiner component 210 that provides an example path combiner output out[k]. In one non-limiting aspect, the low-SPL path can have a gain value K LO selected to meet a desired noise floor for low audio signals, and the high-SPL path can have a gain value K HI selected to meet a maximum SPL level required for the overall digital microphone. In another non-limiting aspect, the value of K LO may be greater than the value of K HI . In addition, unlike AGC approaches (e.g., adjusting an analog scaling factor before the ADC), these gain values K HI and K LOThe state of the art described in U.S. Patent No. 9,673,768 as nominally static rather than varying in dependence on input signal level (although their values can vary under different operating modes of the digital microphone) and / or can in another non-limiting aspect include AGC methods. For example, unlike varying gain values in dependence on input audio signal level as performed in AGC systems, the example multipath digital audio combiner component 210 as described in U.S. Patent No. 9,673,768 can be configured to select the ADC output from the low SPL path or the high SPL path in dependence on input audio signal level.

[0038] As another non-limiting example, for small input audio signal levels, the low SPL path output can be selected (e.g., by the example multipath digital audio combiner component 210 or portions thereof) to output to the example path combiner output out[k], but as the input audio signal level approaches exceeding the maximum SPL range of the low SPL path, the example multipath digital audio combiner component 210 can be further configured to select the high SPL path to output to the example path combiner output out[k].

[0039] In the non-limiting example shown in Figure 2 In the non-limiting example shown in

[0040] Thus, Figure 2The display shows two lower performance ADCs to cover the specified dynamic range, where for small signals, the low SPL path (e.g., including example amplifier or gain stage 202 and example ADC 206) provides the required SNR performance, and where for large signals, the high SPL path (e.g., including example amplifier or gain stage 204 and example ADC 208) path provides the required range (e.g., limited by MEMS 102 and front end 104). It can be appreciated that the high SPL path (e.g., including example amplifier or gain stage 204 and example ADC 208) consumes less power / area because the allowable or tolerable noise can be higher. However, further improvements in power reduction are desired while maintaining a high DR ADC.

[0041] Figure 3 A functional block diagram of an example low power gain stage 300 is shown in accordance with a further non-limiting aspect of the present application. Various non-limiting embodiments as described herein can employ example low power gain stage 300. For example, example low power gain stage 300 can include example amplifier 302 having a capacitance-based feedback network including example feedback capacitors 304 and 306. It can be appreciated that while the switching response of a capacitance-based feedback network amplifier can be relatively slower compared to a resistance-based feedback network amplifier, the example low power gain stage 300 employing a capacitance-based feedback network amplifier can result in lower power consumption due to the stability resulting from AC coupling compared to employing a resistance-based feedback network amplifier.

[0042] Accordingly, Figure 4 A functional block diagram of an example implementation of adaptive ADC 400 is shown in accordance with a further non-limiting aspect of the present application. Various non-limiting embodiments can employ example low power gain stage 300 and example implementation of adaptive ADC 400, e.g., as described further herein. In accordance with one non-limiting aspect, the desired gain variation or scaling factor can be performed within the ADC rather than by an AGC to allow the use of a low power capacitance-based feedback network amplifier rather than a relatively higher power AGC gain adjustment scheme. Thus, example implementation of adaptive ADC 400 can include or be associated with example amplifier 302 employing a capacitance-based feedback network including example feedback capacitors (e.g., one or more example feedback capacitors 304 and 306, etc.). In another non-limiting aspect, example implementation of adaptive ADC 400 can include or be associated with anti-aliasing 402 and example adaptive ADC employing a variable input sampling capacitor 404 network as described herein with respect to Figure 5Further illustrated examples. Although examples gain stages including or associated with example amplifier 302 are shown or described as employing variable capacitance-based feedback networks including example feedback capacitors (e.g., one or more example feedback capacitors 304 and 306, etc.), it should be understood that the various non-limiting embodiments described herein are not so limited. For example, as shown in FIG. 3B, example amplifier 302 employing a capacitance-based feedback network including example feedback capacitors (e.g., one or more example feedback capacitors 304 and 306, etc.) can include a fixed gain, where an adaptive ADC as described herein can be configured to adjust gain by varying from one input sampling capacitance value to another input sampling capacitance value (e.g., by an example ADC range control component (not shown) in accordance with an ADC range control algorithm, etc.). Figure 4 As shown in FIG. 3B, feedback capacitor 304 can include a fixed capacitance value.

[0043] For example, in one non-limiting aspect, example amplifier 302 employing a capacitance-based feedback network including example feedback capacitors (e.g., one or more example feedback capacitors 304 and 306, etc.) can include a fixed gain, where an adaptive ADC as described herein can be configured to adjust gain by varying from one input sampling capacitance value to another input sampling capacitance value (e.g., by an example ADC range control component (not shown) in accordance with an ADC range control algorithm, etc.). For example, for a baseline range defined as C in = C u For example, for a low noise range, for a doubling of C in = 2C u For example, for a low noise range, for a doubling of C Figure 4 as described further with respect to Figure 5 as described further with respect to

[0044] Figure 5 Another functional block diagram 500 of an example aspect of an adaptive ADC in accordance with a further non-limiting aspect of the present application is shown. For example, Figure 5 A portion of an example adaptive ADC including a variable input sampling capacitance 404 is shown. As shown in Figure 5 For a baseline range 502 defined as C in = C u For example, for a low noise range 504, for a doubling of C in = 2C u For example, for a low noise range 504, for a doubling of C Figure 4 For example, for a low noise range 504, for a doubling of C Figure 5 An example variable input sampling capacitance 404 network including a reference capacitor C ref 506 is shown, where V ref 508 is used to compare V in 510 to V ref508For example, an adaptive ADC as described herein can be configured to be gain adjusted by a change in input sampling capacitance value (sometimes referred to herein as a variable sampling capacitor or a variable input sampling capacitor) from one input sampling capacitance value to another input sampling capacitance value (e.g., in accordance with an ADC range control algorithm, etc.) by an example ADC range control component (not shown). Accordingly, Figure 5 An example embodiment showing a variable sampling capacitor or a variable input sampling capacitor comprising a network of capacitors 512, 514, 516 in a switched network arrangement can be used in various embodiments to facilitate changing the input sampling capacitance value 404 by an example ADC range control component (not shown).

[0045] In one non-limiting example, changing the input sampling capacitance 404 to a larger input sampling capacitance value 404 reduces the kT / C noise of an example adaptive ADC, which can increase the signal-to-noise ratio (SNR) and allow the example adaptive ADC to overrange with larger signals. In another non-limiting example, changing the input sampling capacitance 404 to a smaller input sampling capacitance value 404 increases the kT / C noise of an example adaptive ADC, which can decrease the SNR and prevent the example adaptive ADC from overranging with larger signals. It should be appreciated that although Figure 4 and 5 Example embodiments of the two-stage ADC gain control for an example adaptive ADC are shown, but the disclosed subject matter is not so limited. For example, by increasing the number of values for the variable input sampling capacitance 404, the number of stages of ADC gain control provided by employing an example adaptive ADC including a variable input sampling capacitance 404 can be extended to more than two stages.

[0046] Accordingly, Figure 5 Additional non-limiting aspects of example adaptive ADC embodiments employing a variable input sampling capacitance 404 network and reference capacitor C ref 506and having a discrete-time integrator employing an inverter-based amplifier configuration to provide instantaneous discrete-time gain variation on the example adaptive ADC, as described herein. As shown, Figure 5a first stage 518 of a unitary discrete-time delta-sigma ADC employing a variable input sampling capacitance 404 network and a discrete-time integrator using an inverter-based amplifier to provide for instantaneous discrete-time gain variation on the example adaptive ADC, as described herein, for purposes of illustration and not limitation. It should be understood that, in general, a discrete-time delta-sigma ADC can include multiple stages of discrete-time integrators depending on the order of the delta-sigma ADC (e.g., order greater than or equal to 1, with typical values in the range of 2 to 4), where the first stage of the ADC generally determines the noise performance of the overall ADC, and thus is most relevant to the example adaptive ADC as illustrated, as further described herein. Accordingly, in further non-limiting aspects, the output 520 of the first stage 518 of the example adaptive ADC can be fed forward to a further integrator stage (not shown), which can employ a further variable capacitance configuration at the input of the additional integrator stage, as further described herein. Thus, Figure 5 The example shown in FIG. 6 is just one example of a non-limiting aspect of an example adaptive ADC configured as a discrete-time delta-sigma (including a discrete-time integrator configured with an inverter-based amplifier) with a unitary single-ended output, according to a non-limiting aspect of the present disclosure. In other non-limiting aspects, the example adaptive ADC can employ different circuit configurations to provide for instantaneous discrete-time gain variation on the example adaptive ADC, as described herein, including but not limited to different amplifier configurations (e.g., differential or other amplifier configurations), different switching schemes, multi-bit adaptive ADC implementations, successive approximation ADC configurations, employing multiple reference capacitors C ref 506 (e.g., in the case of a multi-bit ADC implementation), etc.

[0047] Accordingly, for example, various non-limiting embodiments as described herein can combine the example adaptive ADC as described herein with the example multi-path digital microphone concepts described herein Figure 2 Thus, Figures 6-7 An example embodiment of an adaptive-ADC-range multi-path digital microphone is shown according to various embodiments described herein. For example, Figure 6 A functional block diagram 600 of an example aspect of an adaptive-ADC-range multi-path digital microphone system according to a non-limiting aspect of the present disclosure is shown. In one non-limiting aspect, the example embodiment of an adaptive-ADC-range multi-path digital microphone allows for an amplifier or gain stage (e.g., as described above with respect to Figures 3-4 the example adaptive ADC (e.g., as described above with respect to Figures 4-5obtain low power. This is due in part to the ability to employ a capacitive feedback structure in the gain stage, in addition to the power savings obtainable by employing a multi-path adaptive ADC, which results in gain stage power savings, allowing lower power ADCs to be employed, as their noise impact is reduced, as described herein. In another non-limiting aspect, for example, an adaptive ADC range multi-path digital microphone system is shown as a digital dual-path microphone system, which can employ a single MEMS acoustic or microphone sensor 102 and a single front-end 104 (e.g., a buffer and charge pump 602) coupling a low SPL path (e.g., including an example low power amplifier or gain stage 604 and an example adaptive ADC 608) and a high SPL path (e.g., including an example low power amplifier or gain stage 606 and an example adaptive ADC 610), as further described herein. Figure 2 Figure 7 Further described are example adaptive ADC range multi-path digital microphone systems configured in example multi-path digital microphone arrangements.

[0048] Accordingly, Figure 6 An example adaptive ADC range multi-path digital microphone system is shown as a digital dual-path microphone system, which can employ a single MEMS acoustic or microphone sensor 102 and a single front-end 104 (e.g., a buffer and charge pump 602) coupling a low SPL path (e.g., including an example low power amplifier or gain stage 604 and an example adaptive ADC 608) and a high SPL path (e.g., including an example low power amplifier or gain stage 606 and an example adaptive ADC 610), as further described herein.

[0049] In one non-limiting aspect, the low SPL path can have a gain value K L selected to meet a desired noise floor for low audio signals, and the high SPL path can have a gain value K H selected to meet a maximum SPL level required for the overall digital microphone. In another non-limiting aspect, the value of K L may be greater than the value of K H . Further, unlike AGC methods (e.g., adjusting an analog scaling factor prior to the ADC), these gain values K H and K L may be nominally static, rather than varying as a function of input signal level (although their values can vary under different operating modes of the digital microphone), and / or can include aspects of AGC methods in another non-limiting aspect.

[0050] Accordingly, Figure 6 ​An example adaptive ADC range multi-path digital microphone system of the present disclosure can include one or more adaptive ADCs that can be configured to generate one of one or more digital audio signals having different scaling factors of an associated audio signal. As a non-limiting example, the one or more adaptive ADCs can be configured to adjust a gain by a change in one or more input sampling capacitance values of an associated one of the one or more adaptive ADCs from one of the one or more input sampling capacitance values of the associated one of the one or more adaptive ADCs to another of the one or more input sampling capacitance values of the associated one of the one or more adaptive ADCs by the ADC range control component in accordance with an ADC range control algorithm, as further described herein. In one non-limiting example, another of the one or more adaptive ADCs can be configured to provide a low power audio signal relative to a power of the one or more digital audio signals having different scaling factors. For example, as further described herein, the one or more adaptive ADCs can be configured to provide a low power audio signal relative to a power of the one or more digital audio signals having different scaling factors by reducing a sampling rate, reducing a power amplifier, changing a sampling capacitance, etc. Figure 10 as further described herein.

[0051] In another non-limiting example, the one or more adaptive ADCs can also be configured (e.g., reduce a sampling rate, reduce a power amplifier, change a sampling capacitance, etc.) to be placed in a first low power mode to provide a low power audio signal relative to a power of the one or more digital audio signals having different scaling factors, as further described herein. In another non-limiting example, a low power mode adaptive ADC of the one or more adaptive ADCs can be configured to provide a second low power mode, wherein the one or more adaptive ADCs other than the low power mode adaptive ADC can also be configured to be turned off to provide the second low power mode. As further described herein, in further non-limiting examples, an example adaptive ADC can include a sigma delta modulator or a successive approximation ADC configured as an ADC.

[0052] In non-limiting examples, Figure 6 An example adaptive ADC range multi-path digital microphone system of the present disclosure can also include one or more digital audio filters (e.g., integer decimation filters, low pass filters, etc.) 612 and 614 operably coupled to respective example adaptive ADCs 608, 610 (e.g., Sigma Delta modulators) that can be configured to receive digital audio signals having different scaling factors of an associated audio signal (e.g., by example adaptive ADCs 608, 610) and can be configured to provide filtered digital audio signals.

[0053] In further non-limiting examples, Figure 6The example adaptive ADC range multi-path digital microphone system of can also include an example ADC range control component 616 configured to adjust the gain of one or more of the example adaptive ADCs 608, 610 based in part on a respective sound pressure level threshold sensed in the digital audio signal having a different scaling factor (e.g., by one or more digital audio filters (e.g., integer downsample rate filters, low pass filters, etc.) 612 and 614), as described herein.

[0054] In one non-limiting aspect, Figure 6 The example adaptive ADC range multi-path digital microphone system of can also include one or more gain compensation components 618, 620 associated with one of the digital audio signals having a different scaling factor (e.g., by one or more digital audio filters (e.g., integer downsample rate filters, low pass filters, etc.) 612 and 614). In further non-limiting embodiments, the example ADC range control component 616 can also be configured to continuously adjust the gain of one or more of the gain compensation components 618, 620 to compensate for changes in the gain of the example adaptive ADCs 608, 610.

[0055] In another non-limiting aspect, Figure 6 The example adaptive ADC range multi-path digital microphone system of can also include a digital data path configured to avoid audible artifacts during gain and / or path changes. For example, Figure 6 The example adaptive ADC range multi-path digital microphone system of can also include an example glitch elimination component 622 configured to minimize audible artifacts associated with changes in the gain of the example adaptive ADCs 608, 610, as described further herein, for example with respect to Figure 8 As one non-limiting example, the example glitch elimination component can also be configured to minimize audible artifacts based on changes in the gain of one or more of the adaptive ADCs determined by the ADC range control component through a glitch elimination algorithm. For example, in one non-limiting aspect, the example glitch elimination component can also be configured to minimize audible artifacts through the glitch elimination algorithm including one or more of zero-crossing detection, filtering, or signal prediction. Further non-limiting examples of example glitch elimination algorithms are described below with respect to Figure 8 Figure 6 The example adaptive ADC range multi-path digital microphone system of also shows signal paths in-lo[k] 624, in-hi[k] 626, in-hi_selected[k] 628, and clk_div_by_8(t) 630, as described herein, for example with respect to​Figure 7 , 9 and further described by others.

[0056] In further non-limiting aspects, Figure 6 An example adaptive ADC range multi-path digital microphone system of the present disclosure can include a multiplexing component that can be configured to switch passing one digital audio signal associated with the one or more adaptive ADCs and another digital audio signal associated with another of the one or more adaptive ADCs, as further described herein.

[0057] Further, Figure 6 An example adaptive ADC range multi-path digital microphone system of the present disclosure can include an output component that can be configured to transmit a digital signal based on one or more digital audio signals, including one or more of a pulse-density modulation (PDM) signal, an integrated interchip sound (I 2 S) signal, a time-division multiplexed signal, or a Soundwire signal, as further described herein. For example, in accordance with further non-limiting aspects, an example output component can include one or more of a non-linearity compensation component, a filtering component, a digital gain adjustment component, or a signal reshaper component.

[0058] As described above, the term adaptive ADC and the like can be understood to refer to one or more components that can be configured to operate and / or facilitate a variable scaling factor on the ADC from input to output (e.g., through a variable sampling capacitor or other components of the ADC, etc.) to allow for changing the range or gain of the ADC depending on context. For example, in non-limiting examples described in Figure 6

[0059] Figure 7 ​Another functional block diagram 700 of an example adaptive ADC range multi-path digital microphone system in accordance with yet another non-limiting aspect of the present disclosure is shown. In accordance with aspects of the present disclosure, an example adaptive ADC range multi-path digital microphone system in accordance with Figure 7 may include a multi-path digital combiner component, e.g., a two-path digital combiner audio combiner component 702, etc., as described above with respect to the non-limiting implementation of the two-path digital combiner audio combiner component 2. In yet another non-limiting aspect, an example multi-path digital combiner component, e.g., a two-path digital combiner audio combiner component 702, etc., can include or be associated with a multiplexing component configured to switch passing one digital audio signal associated with one of the one or more example adaptive ADCs 608, 610, e.g., one of in-lo[k] 624, in-hi[k] 626, etc., and another digital audio signal associated with another of the one or more example adaptive ADCs 608, 610, e.g., the other of in-lo[k] 624, in-hi[k] 626, etc.

[0060] In accordance with aspects of the present disclosure, an example adaptive ADC range multi-path digital microphone system in accordance with Figure 7 may further include an example output component 704 that can be configured to transmit a digital signal based on the plurality of digital audio signals, including at least one of a pulse density modulation (PDM) signal, an integrated inter-chip sound (I2S) signal, a time-division multiplexed signal, or a Soundwire signal. In another non-limiting aspect, the example output component 704 can include one or more of a filter component, e.g., a compression filter 706, etc., a digital gain adjustment component, e.g., a digital multiplier 708, etc., a non-linearity compensation component 710, or a signal shaper component, e.g., a shaper 712, etc., to facilitate transmitting a digital signal 714. 2 S) signal, a time-division multiplexed signal, or a Soundwire signal. In another non-limiting aspect, the example output component 704 can include one or more of a filter component, e.g., a compression filter 706, etc., a digital gain adjustment component, e.g., a digital multiplier 708, etc., a non-linearity compensation component 710, or a signal shaper component, e.g., a shaper 712, etc., to facilitate transmitting a digital signal 714.

[0061] It should be appreciated that, although various components in Figures 6-7 are shown as being combined, controlling both adaptive ADCs 608, 610, e.g., the ADC range control component 616 controls both adaptive ADCs 608, 610, for ease of illustration, it should be appreciated that each of the two adaptive ADCs 608, 610 has its own unique ADC range control state machine, e.g., as further described herein with respect to Figure 9 .

[0062] Figure 8Another functional block diagram 800 of an example adaptive ADC range multi-path digital microphone system in accordance with a further non-limiting aspect of the present application is shown. In various non-limiting embodiments, the example adaptive ADC range multi-path digital microphone system can employ an example glitch elimination component 622 configured to minimize audible artifacts associated with changes in gain of the example adaptive ADCs 608, 610, such as described herein with respect to Figure 6 Further, the example glitch elimination component 622 can also be configured to minimize audible artifacts based on changes in gain of the example adaptive ADCs 608, 610 determined by the example ADC range control component 616 through an example glitch elimination algorithm. In further non-limiting aspects, the example glitch elimination algorithm can include or be based on any number of glitch elimination algorithms including zero-crossing detection, filtering, extrapolation, etc.

[0063] Accordingly, Figure 8 An example glitch elimination algorithm for an example glitch signal (dec_comp[k]) 802 for illustrative and non-limiting purposes based on non-limiting assumptions of a 2ndorder 3-bit example adaptive ADC 608 and example filter (CIC 4 8x integer decimator) 612 is shown, where the example glitch signal (dec_comp[k]) 802 is modeled as a glitch limited to 3 samples at 8x decimation rate. Accordingly, the example glitch elimination algorithm can include a 5-tap FIR filter configured to process the decimator output, where the example glitch elimination component 622 can eliminate the assumed 3 dominant glitch samples by timely multiplexing filter states 804 (outO to out7) and then returning outO when a gain change occurs in the example adaptive ADC 608, providing an output (out[k]) 806 that eliminates the example glitch signal (dec_comp[k]) 802, as further described below. Thus, example embodiments can employ an example glitch elimination algorithm that filters out glitch samples. As described above, other non-limiting embodiments can employ an example glitch elimination algorithm that dynamically changes tap weights to eliminate glitch samples while preserving valid signal samples. In other non-limiting embodiments, the example glitch elimination algorithm can include employing gain changes at lower (e.g., approximately zero) input amplitudes to avoid and / or minimize glitch signal power. In further non-limiting embodiments, the example glitch elimination algorithm can employ signal prediction or prediction methods (e.g., extrapolation from valid signal values, etc.) to predict suitable signal samples during the expected glitch transient.

[0064] Figure 9The display of additional aspects in accordance with the present application include a non-limiting state diagram 900 of an example digital microphone system configured with a non-limiting implementation of adaptive ADCs of a two-path digital audio combiner component. As described above, it should be understood that although various components in Figures 6-7 are shown as combined, controlling both adaptive ADCs 608, 610 (e.g., ADC range control component 616 controls both adaptive ADCs 608, 610), it should be appreciated that each of the two adaptive ADCs 608, 610 has its own unique ADC range control state machine, as further described herein. Thus, Figure 9 The state diagram 900 displays the transition between gain states of the example adaptive ADC. For example, adc gain 902 is defined as the example adaptive ADC gain, where 0 represents the gain of the baseline state of the example adaptive ADC (e.g., ADC gain = 1 as an illustrative example), and where 1 represents the gain of the high gain state (e.g., ADC gain = 2 as an illustrative example), as described above with respect to Figures 4-5 .

[0065] Further, ma_filt_gain 904 is defined as the moving average filter gain, which is a digital compensation gain to compensate for the ADC gain (e.g., gain compensation components 618, 620, 1012, etc.), where ma_filt_gain = 0 represents a digital gain of 1 as an illustrative example, and where ma_filt_gain = 1 represents a digital gain of 1 / 2. As another example, ma_filt_ctrl 906 controls the operation of the glitch removal algorithm, where the glitch removal component operates through Figure 8 the filter states 804 (outO-out7) in

[0066] In another example, counter_gain_chg 908 allows for setting a delay before switching the gain from the low gain to the high gain to avoid ADC saturation. For example, if in the high gain state (adc_gain = 1), it is possible to immediately go to the low gain state (adc_gain = 0) to avoid ADC saturation. However, if in the low gain state (adc_gain = 0), the system goes through a counter operation to provide a delay before returning to the high gain state (adc_gain = 1), as further described below.

[0067] In the S0 state (baseline state) 910, adc_gain = 0, ma_filt_gain = 0, ma_filt_ctrl = 0, counter_gain_chg = 0. If the signal is small (|adc_val| <= level_thresh_lo, where adc_val is the integer decimated adc_val), the system can go to a higher gain state (adc_gain = 1) to provide a higher SNR.

[0068] Thus, the S1 state (counter_cntrl = 0; incr_counter_gain_chg = 0) 912, when going from the baseline state S0 (adc_gain = 0), where if the signal is small (|adc_val| <= level_thresh_lo, where adc_val is the integer decimated adc_val), the system can go to a higher gain state (adc_gain = 1) to provide a higher SNR. Thus, before switching to the high gain (adc_gain = 1), the system starts a counter (num_gain_chg_cycles 914). If the full number of cycles of the counter are experienced, then the system can set the ADC gain to the higher gain state (adc_gain = 1) in state S2 (adc_gain = 1) 916.

[0069] However, if during the operation of this counter, if the signal becomes larger,

[0070] |adc_val| > level_thresh_lo, then the system remains in state S0 910 at the baseline state (adc_gain = 0).

[0071] The S2 state 916, adc_gain = 0, incr. counter_cntrl. At this point, the system starts controlling the digital compensation gain (moving average filter gain) after a delay (ma_filt_ctrl_delay 918), which in one non-limiting example is configurable. Again referring to Figure 6 and 7 If an ADC gain change occurs through ADC range control, the gain change signal needs some time to propagate through the ADC and integer decimator, after which the start of glitch 802 will occur (some time after the ADC gain change). Thus, the system can employ the ma_filt_ctrl_delay 918 to control how long after the ADC gain change the system will start ignoring glitches to avoid removing valid signal data, but only removing unwanted glitch samples.

[0072] After the delay (ma_filt_ctrl_delay 918) is complete, the system begins controlling the moving average filter gain (ma_filt_gain = 1) at state S3 920 to compensate for the ADC gain change (e.g., adc_gain = 0 to adc_gain = 1).

[0073] S3 state 920, ma_filt_gain = 1, incr.ma_filt_ctrl. When the glitch removal component 622 orders the ma_filt_ctrl 906 through the filter state 404 (outO-out7), as described above for Figure 8 the glitch removal is performed, after which state S4 922 is reached.

[0074] In the S4 state (high gain state) 922, adc_gain = 1, ma_filt_gain = 1, ma_filt_ctrl = 0, counter_gain_chg = 0. As long as the signal remains low, the system remains in the high gain state (adc_gain = 1). When the signal becomes large and exceeds level_thresh_hi (e.g., |adc_val| > level_thresh_hi), the system proceeds to state S5 924 to avoid ADC saturation, where the system proceeds to the low ADC gain state (adc_gain = 0).

[0075] S5 state 924, adc_gain = 0, incr.counter_cntrl. At this point, the system begins controlling the digital compensation gain (moving average filter gain) after a delay (ma_filt_ctrl_delay), which in one non-limiting example is configurable, to properly remove glitches, as described above. After the delay (ma_filt_ctrl_delay 918) is complete, the system begins controlling the moving average filter gain (ma_filt_gain = 0) at state S6 926 to compensate for the ADC gain change (e.g., adc_gain = 1 to adc_gain = 0).

[0076] S6 state 926, ma_filt_gain = 0, incr.ma_filt_ctrl. When the glitch removal component 622 orders the ma_filt_ctrl 906 through the filter state 404 (outO-out7), as described above for Figure 8 the glitch removal is performed, after which state S0 910 is reached again, where adc_gain = 0 and ma_filt_gain = 0.

[0077] Figure 10 A functional block diagram of an example aspect of an adaptive ADC range multi-path digital microphone system 1000 is shown in accordance with non-limiting aspects described herein. Figure 10 An example aspect of an adaptive ADC range multi-path digital microphone is shown in accordance with various embodiments described herein. Figures 3-8 The example adaptive ADC range multi-path digital microphone. In accordance with further non-limiting embodiments, the example adaptive ADC range multi-path digital microphone can provide one or more low power modes. Accordingly, in one non-limiting aspect, for example, by setting the input sampling capacitance value 404 to a low power mode capacitance value, one or more example adaptive ADCs 608, 610 can also be configured to be placed in a low power mode to provide a low power audio signal relative to the power of the filtered digital audio signal in normal operation. In another non-limiting aspect, one or more example adaptive ADCs 608, 610 or associated data paths, etc. can be turned off to further provide a low power mode that can be used in various non-limiting embodiments described herein.

[0078] In accordance with further non-limiting embodiments, the example adaptive ADC range multi-path digital microphone can provide another low power mode including an example alternative low power audio path to provide a low power audio output pdm_lpm[k] 1002, for example, as shown in Figures 6-8 It should be appreciated that although the example alternative low power audio path is shown to include one or more example low power amplifiers or gain stages MIV, example adaptive ADCs 1006, example filters 1008, example ADC range controls 1010, example gain compensation components 1012, example glitch removal components 1014, etc., one or more of these components or portions thereof can be repurposed from the above described data paths. Further, the example alternative low power audio path can also include one or more of a low power gain stage (digital multiplier) 1016 and a low power data path shaper 1018. Accordingly, the example adaptive ADC range multi-path digital microphone can provide another low power mode including a low power mode adaptive ADC 1006 that can be configured to provide a second low power mode in which the example adaptive ADCs 608, 610 can be configured to be turned off to provide the second low power mode. Figure 11 The data paths repurposed as described above. Further, the example alternative low power audio path can also include one or more of a low power gain stage (digital multiplier) 1016 and a low power data path shaper 1018. Accordingly, the example adaptive ADC range multi-path digital microphone can provide another low power mode including a low power mode adaptive ADC 1006 that can be configured to provide a second low power mode in which the example adaptive ADCs 608, 610 can be configured to be turned off to provide the second low power mode.

[0079] Figure 10Another functional block diagram of an example adaptive ADC range multi-path digital microphone system 1100 in accordance with still another non-limiting aspect of the present application is shown. As a non-limiting example, in addition to various components described herein with respect to 3-8, 10, etc., the example adaptive ADC range multi-path digital microphone system 1100 can include an activity detection component 1102 configured to provide an indication of an absence of audio activity, and an output component 1104 configured to determine whether to transmit a digital signal low-power audio signal (e.g., by way of an example low-power audio signal data path, etc.) based on the absence of audio activity, where the digital signal includes at least one of a pulse density modulation (PDM) signal, an integrated inter-chip sound (I2S) signal, a time-division multiplexed signal, or a Soundwire signal. In another non-limiting aspect, the output component includes at least one of a non-linearity compensation component, a filtering component, or a signal shaper component, as further described herein. Figure 12 2 Accordingly, the example adaptive ADC range multi-path digital microphone system 1100 can include a first circuit having at least one input operably coupled to at least one MEMS acoustic sensor to receive at least one electrical signal varying in accordance with at least one acoustic signal via the input, the first circuit having at least one output (e.g., at one or more of the example low-power gain stages 604, 606, 1004) and configured to process the at least one electrical signal and configured to provide at least one corresponding processed electrical signal at the at least one output.

[0080] Accordingly, the example adaptive ADC range multi-path digital microphone system 1100 can include a first circuit having at least one input operably coupled to at least one MEMS acoustic sensor to receive at least one electrical signal varying in accordance with at least one acoustic signal via the input, the first circuit having at least one output (e.g., at one or more of the example low-power gain stages 604, 606, 1004) and configured to process the at least one electrical signal and configured to provide at least one corresponding processed electrical signal at the at least one output.

[0081] Accordingly, the example adaptive ADC range multi-path digital microphone system 1100 can include a first circuit having at least one input operably coupled to at least one MEMS acoustic sensor to receive at least one electrical signal varying in accordance with at least one acoustic signal via the input, the first circuit having at least one output (e.g., at one or more of the example low-power gain stages 604, 606, 1004) and configured to process the at least one electrical signal and configured to provide at least one corresponding processed electrical signal at the at least one output.

[0082] ​In another non-limiting aspect, the example adaptive ADC range multi-path digital microphone system 1100 can further include one or more amplifiers (e.g., one or more of the example low power gain stages 604, 606, 1004) operably coupled to the at least one output, wherein the one or more amplifiers can be configured to receive the at least one corresponding processed electrical signal, and wherein the one or more amplifiers can be configured to apply one or more first scaling factors to the at least one corresponding processed electrical signal.

[0083] In another non-limiting aspect, the example adaptive ADC range multi-path digital microphone system 1100 can further include one or more example adaptive ADCs (e.g., one or more of the example adaptive ADCs 608, 610, 1006) respectively operably coupled to one of the one or more outputs associated with the one or more amplifiers and respectively configured to provide a respective one of one or more digital audio signals having different scaling factors associated with the at least one acoustic signal. In another non-limiting aspect, the one or more adaptive ADCs can be configured to have their gain adjusted by the ADC range control component in accordance with an ADC range control algorithm by a change from one of the one or more input sampling capacitance values of the one of the one or more adaptive ADCs to another of the one or more input sampling capacitance values of the one of the one or more adaptive ADCs, as further described herein. In another non-limiting aspect, the one or more adaptive ADCs can be further configured to be placed in a first low power mode (e.g., reduce sampling rate, reduce power amplifier, change sampling capacitance, etc.). The example adaptive ADC range multi-path digital microphone system 1100 can further include a low power mode adaptive ADC (e.g., the example adaptive ADC 1006) configured to provide a second low power mode, wherein the one or more adaptive ADCs other than the low power mode adaptive ADC can be configured to be turned off to provide the second low power mode.

[0084] In one non-limiting aspect, the example adaptive ADC range multi-path digital microphone system 1100 can further include one or more digital audio filters (e.g., one or more of the filters 612, 614, 1008) respectively operably coupled to one of the one or more adaptive ADCs, respectively configured to receive the respective one of the one or more digital audio signals having different scaling factors, and configured to provide one or more filtered digital audio signals. In another non-limiting aspect, the one or more digital audio filters include at least one of one or more integer decimators or one or more low pass filters, as further described herein.

[0085] In another non-limiting aspect, the example adaptive ADC range multi-path digital microphone system 1100 can also include an ADC range control component (e.g., ADC range control component 616, 1010, etc.) configured to adjust a gain of at least one of the one or more adaptive ADCs based at least in part on a respective sound pressure level threshold sensed in at least one of the one or more filtered digital audio signals.

[0086] In another non-limiting aspect, the example adaptive ADC range multi-path digital microphone system 1100 can also include one or more gain compensation components (e.g., one or more gain compensation components 618, 620, 1012, etc.) respectively associated with one of the one or more filtered digital audio signals, wherein the ADC range control component is further configured to continuously adjust a gain of at least one of the gain compensation components to compensate for a change in the gain of the at least one of the one or more adaptive ADCs.

[0087] In one non-limiting aspect, the example adaptive ADC range multi-path digital microphone system 1100 can also include a glitch elimination component (e.g., glitch elimination component 622, 1014, etc.) configured to minimize audible artifacts associated with the change in the gain of the at least one of the one or more adaptive ADCs. In another non-limiting aspect, the glitch elimination component is further configured to minimize audible artifacts through a glitch elimination algorithm based on the change in the gain of the at least one of the one or more adaptive ADCs determined by the ADC range control component, as further described herein. In another non-limiting aspect, the glitch elimination component is further configured to minimize audible artifacts through the glitch elimination algorithm including at least one of zero-crossing detection, filtering, or signal prediction, as further described herein.

[0088] In another non-limiting aspect, the example adaptive ADC range multi-path digital microphone system 1100 can also include a multiplexing component (not shown, e.g., a multiplexing component of the multi-path digital audio combiner component 210, 710, included in the output component 1104, etc.) configured to switch passing one of the digital audio signals associated with the at least one of the one or more adaptive ADCs and another digital audio signal associated with another of the one or more adaptive ADCs.

[0089] As described herein, various alternatives to the embodiments are considered in non-limiting embodiments. For example, one or more of the embodiments may be used with one or more other sensors, including but not limited to acoustic sensors (e.g., microphones, ultrasonic sensors, etc.), environmental sensors (e.g., pressure sensors, temperature sensors, gas sensors, etc.), motion sensors (e.g., accelerometers, gyroscopes, etc.). Other non-limiting alternative embodiments consider employing an adaptive ADC as described herein by means of a successive approximation ADC. In further non-limiting alternative embodiments, one or more other components may replace the functional equivalents and / or various forms of the adaptive ADC as described herein may be used in specified other designs that may employ a subset of the various non-limiting forms described herein.

[0090] For example, Figures 6-11 A functional block diagram 1200 shows an example configuration of an adaptive ADC range digital microphone according to a non-limiting configuration of this application. (Refer to the above...) Figure 12 The components described herein are understood to be Figure 12 The various components are shown. Accordingly, from Figure 10 Understandably, the example digital microphone (or one or more other sensors) may employ an adaptive ADC range, where it is desirable to facilitate a variable scaling factor on the ADC from input to output, allowing for changes in the ADC's range or gain. This is achieved through... Figure 12 In comparison, it is important to note that Figure 10 The example embodiment is not necessarily referred to as a low-power audio path (but it may be in a particular embodiment) because it lacks another signal path for comparing relative power levels. It should also be noted that in a non-limiting example, although... Figure 12 The example embodiment shows an example filter 1008 (e.g., decimation by 4 integer multiples), but Figure 12 The example embodiment shows an example filter 1008 (e.g., decimation by 8 integer multiples). In Figure 10 In other non-limiting embodiments, the adaptive ADC 632 may also refer to one or more other components (e.g., a successive approximation ADC, etc.) that facilitate a variable scaling factor on the ADC from input to output to allow for changes in the range or gain of the ADC, as further described herein. It should also be noted that in one non-limiting embodiment, with Figures 13-14 In contrast, the example gain stage 1004 is not specifically described and depends on design requirements.

[0091] Accordingly, in further non-limiting embodiments, an example adaptive ADC range digital microphone can include an adaptive ADC that can be configured to generate digital audio signals having different scaling factors of an associated audio signal, as described herein. In one non-limiting aspect, the adaptive ADC can be configured to adjust a gain by the ADC range control component from a change of one of a plurality of input sampling capacitance values of the adaptive ADC to another of the plurality of input sampling capacitance values of the adaptive ADC in accordance with an ADC range control algorithm, as further described herein. In further non-limiting embodiments, the adaptive ADC can include a sigma delta modulator or a successive approximation ADC configured as an ADC, as described above.

[0092] In further non-limiting embodiments, an example adaptive ADC range digital microphone can also include a gain compensation component associated with the digital audio signals having different scaling factors, wherein the ADC range control component can also be configured to continuously adjust a gain of the gain compensation component to compensate for the change in the gain of the adaptive ADC, as further described herein.

[0093] In further non-limiting embodiments, an example adaptive ADC range digital microphone can also include an ADC range control component that can be configured to adjust a gain of the adaptive ADC based on respective sound pressure level thresholds sensed in the digital audio signals having different scaling factors.

[0094] Further, and in other non-limiting embodiments, an example adaptive ADC range digital microphone can also include a glitch elimination component that can be configured to minimize audible artifacts associated with the change in the gain of the adaptive ADC, as described herein. In another non-limiting aspect, an example glitch elimination component can also be configured to minimize audible artifacts by a glitch elimination algorithm based on the change in the gain of the adaptive ADC determined by the ADC range control component, as described above. In further non-limiting aspects, an example glitch elimination component can also be configured to minimize audible artifacts by the glitch elimination algorithm including one or more of zero-crossing detection, filtering, or signal prediction, as described herein.

[0095] In other non-limiting embodiments, an example adaptive ADC range digital microphone can also include a digital audio filter operably coupled configured as a sigma delta modulator of the ADC that can be configured to receive the digital audio signals having different scaling factors of the associated audio signal and can be configured to provide a filtered digital audio signal, as further described herein. For example, in another non-limiting aspect, an example digital audio filter can include one or more of an integer decimator or a low pass filter.

[0096] In other non-limiting embodiments, example adaptive ADC range digital microphones can also include an output component that can be configured to transmit a digital signal based on the digital audio signal, including one or more of a pulse density modulation (PDM) signal, an integrated inter-chip sound (I2S) signal, a time-division multiplexed signal, or a Soundwire signal, as further described herein. In another non-limiting aspect, example output components can include one or more of a non-linearity compensation component, a filtering component, a digital gain adjustment component, or a signal shaper component, as described above. 2 S) signal, a time-division multiplexed signal, or a Soundwire signal, as further described herein. In another non-limiting aspect, example output components can include one or more of a non-linearity compensation component, a filtering component, a digital gain adjustment component, or a signal shaper component, as described above.

[0097] In view of the subject matter described herein, reference is made to the Figure 13 flowchart diagrams that can be implemented in accordance with the present application. Although the methods are shown and described as a series of blocks, it is to be appreciated that such illustrations are not limiting and that the blocks can be performed in different orders and / or concurrently with one another. Any non-sequential or branched flow illustrated by the flowcharts should be understood to represent various other branched, flow paths and orders of blocks that achieve the same or similar results. Furthermore, not all illustrated blocks can be required to implement the methods described herein.

[0098] Example methods

[0099] Figure 14 An example flowchart diagram of a non-limiting method 1300 associated with various non-limiting embodiments of the present application is shown.

[0100] Example method 1300 can include, at 1302, generating one or more digital audio signals with one or more adaptive analog-to-digital converters (ADCs), the digital audio signals having different scaling factors associated with the audio signals, as further described herein. In one non-limiting aspect, the generating the one or more digital audio signals can include generating the one or more digital audio signals with another of the one or more adaptive ADCs configured to provide a low-power audio signal relative to a power of the one or more digital audio signals having different scaling factors, as further described herein. In another non-limiting aspect, generating the one or more digital audio signals can include generating the one or more digital audio signals with at least one of the one or more adaptive ADCs including one or more sigma delta modulators or one or more successive approximation ADCs configured as ADCs, as further described herein.

[0101] The example method 1300 can also include, at 1304, adjusting a gain of at least one of the one or more adaptive ADCs by an ADC range control component configured to adjust the gain based on a respective sound pressure level threshold sensed in at least one of the one or more digital audio signals having different scaling factors, as further described herein. In another non-limiting aspect, the adjusting the gain of the at least one of the one or more adaptive ADCs by the ADC range control component can include adjusting the gain of the at least one of the one or more adaptive ADCs by the ADC range control component in accordance with an ADC range control algorithm by changing one of one or more input sampling capacitance values of an associated one of the one or more adaptive ADCs to another of the one or more input sampling capacitance values of the associated one of the one or more adaptive ADCs, as further described herein.

[0102] The example method 1300 can include, at 1306, adjusting a gain by one or more gain compensation components respectively associated with one of the one or more digital audio signals having different scaling factors, wherein the ADC range control component can also be configured to continuously adjust the gain of at least one of the gain compensation components to compensate for the change in the gain of the at least one of the one or more adaptive ADCs, as further described herein.

[0103] In other non-limiting embodiments, the example method 1300 can include, at 1308, eliminating at least one glitch associated with the one or more digital audio signals having different scaling factors by a glitch elimination component configured to minimize audible artifacts associated with the change in the gain of the at least one of the one or more adaptive ADCs. In another non-limiting aspect, the eliminating at least one glitch associated with the one or more digital audio signals having different scaling factors by the glitch elimination component can include eliminating at least one glitch in accordance with a glitch elimination algorithm based on the change in the gain of the at least one of the one or more adaptive ADCs determined by the ADC range control component, as further described herein. In another non-limiting aspect, the eliminating the at least one glitch can include eliminating the at least one glitch in accordance with the glitch elimination algorithm including at least one of zero-crossing detection, filtering, or signal prediction, as further described herein.

[0104] The example method 1300 can include, at 1310, switching passing a digital audio signal associated with the at least one of the one or more adaptive ADCs and another digital audio signal associated with another of the one or more adaptive ADCs, as further described herein.

[0105] The example method 1300 can also include transmitting, at 1312, a digital signal based on the one or more digital audio signals, including at least one of transmitting a pulse density modulation (PDM) signal, an integrated inter-chip sound (I2S) signal, a time-division multiplexed signal, or a Soundwire signal. In another non-limiting aspect, transmitting the digital signal can include transmitting the digital signal through at least one of a non-linearity compensation component, a filter component, a digital gain adjustment component, or a signal shaper component, as further described herein. 2 S) signal, a time-division multiplexed signal, or a Soundwire signal. In another non-limiting aspect, transmitting the digital signal can include transmitting the digital signal through at least one of a non-linearity compensation component, a filter component, a digital gain adjustment component, or a signal shaper component, as further described herein.

[0106] The example method 1300 can also include placing the one or more adaptive ADCs in a first low power mode (e.g., reducing a sampling rate, reducing a power amplifier, changing a sampling capacitance, etc.). Additionally, the example method 1300 can also include placing the one or more adaptive ADCs in a second low power mode, including selecting a low power mode adaptive ADC of the one or more adaptive ADCs configured to provide the second low power mode, wherein the one or more adaptive ADCs other than the low power mode adaptive ADC can be configured to be turned off, thereby providing the second low power mode.

[0107] Additionally, the example method 1300 can also include receiving the one or more digital audio signals with one or more digital audio filters respectively operatively coupled to one of the one or more sigma delta modulators configured as an ADC, wherein the one or more digital audio filters can be configured to receive one of the one or more digital audio signals having a different scaling factor of the associated audio signal and configured to provide one or more filtered digital audio signals. In another non-limiting aspect, receiving the one or more digital audio signals with the one or more digital audio filters can include receiving the one or more digital audio signals with at least one of one or more integer decimators or one or more low pass filters, as further described herein.

[0108] ​ Another example flow diagram of an additional non-limiting method 1300 associated with various non-limiting embodiments of the present application is shown.

[0109] The example method 1400 can include, at 1402, generating, with an adaptive analog-to-digital converter (ADC), a digital audio signal having different scaling factors associated with an audio signal, as described further herein. In one non-limiting aspect, generating the digital audio signal can include generating, with the adaptive ADC, the digital audio signal including a sigma delta modulator or a successive approximation ADC configured as an ADC, as described further herein.

[0110] The example method 1400 can also include, at 1404, adjusting, by an ADC range control component, a gain of the adaptive ADC configured to adjust a gain based at least in part on a respective sound pressure level threshold sensed in the digital audio signal having different scaling factors. In another non-limiting aspect, adjusting, by the ADC range control component, the gain of the adaptive ADC can include adjusting, by the ADC range control component, the gain of the adaptive ADC from one of a plurality of input sampling capacitance values of the adaptive ADC to another of the plurality of input sampling capacitance values of the adaptive ADC according to an ADC range control algorithm, as described further herein.

[0111] The example method 1400 can include, at 1406, adjusting, by a gain compensation component associated with the digital audio signal having different scaling factors, a gain, wherein the ADC range control component can also be configured to continuously adjust a gain of the gain compensation component to compensate for the change in the gain of the adaptive ADC, as described further herein.

[0112] In other non-limiting embodiments, the example method 1400 can include, at 1408, eliminating, by a glitch elimination component, at least one glitch associated with the digital audio signal having different scaling factors, the glitch elimination component configured to minimize audible artifacts associated with the change in the gain of the adaptive ADC. In another non-limiting aspect, eliminating, by the glitch elimination component, at least one glitch associated with the digital audio signal having different scaling factors can include eliminating at least one glitch according to a glitch elimination algorithm based on the change in the gain of the adaptive ADC determined by the ADC range control component, as described further herein. In another non-limiting aspect, eliminating the at least one glitch can include eliminating the at least one glitch according to the glitch elimination algorithm including at least one of zero crossing detection, filtering, or signal prediction, as described further herein.

[0113] The example method 1400 can also include, at 1410, transmitting a digital signal based on the digital audio signal, including transmitting a pulse density modulation (PDM) signal, an integrated inter-chip sound (I2S) signal, or a time-division multiplexed (TDM) signal, as described further herein. 2S) at least one of a signal, a time division multiplexed signal, or a Soundwire signal. In another non-limiting aspect, transmitting the digital signal can include transmitting the digital signal through at least one of a non-linear compensation component, a filtering component, a digital gain adjustment component, or a signal shaper component, as further described herein.

[0114] In addition, example method 1400 can also include receiving the digital audio signal with a digital audio filter operably coupled to the sigma delta modulator configured as the ADC, where the digital audio filter can be configured to receive the digital audio signal with a different scaling factor than the associated audio signal and configured to provide a filtered digital audio signal. In another non-limiting aspect, receiving the digital audio signal with the digital audio filter can include receiving the digital audio signal with at least one of an integer down-sampler or a low pass filter, as further described herein.

[0115] The above specification, including the claims, has used a plurality of terms which shall have been presented for the purpose of illustration and description and not for limitation. It is intended that wherever words such as "comprise" and "have" are used, there shall be no limitation to any specific inclusion. For example, a system, structure, or apparatus that "comprises" or "has" an element or component can include elements or components in addition to that element or component. Further, it is intended that singular adjectives and antecedents be read to encompass the plural and vice versa, unless explicitly stated otherwise. As used herein, "for example" means "for the purpose of illustration and description, but not for limitation."

[0116] As used in this application, the terms "component," "module," "system," and the like are intended to refer to a computer-related entity, either hardware, a combination of hardware and software, software, or software in execution. For example, a component or module can be, but is not limited to being, a process running on a processor, a processor or portion thereof, a hard disk drive, multiple storage drives (optical and / or magnetic storage media), an object, an executable, a thread of execution, a program, and / or a computer. By way of illustration, both an application running on a server and the server can be a component or module. One or more components or modules can reside within a process and / or thread of execution and a component or module can be localized on one computer or processor or distributed across two or more computers or processors.

[0117] As used herein, the term "inference" generally refers to the process of reasoning or inferring a state of the system and / or environment from a set of observations of events, signals, and / or data. Inference can be probabilistic, such as deducing a likelihood that a state is true based on observations of events and / or data or deterministic, such as a short list of state hypotheses directly derived from a set of observations of events and / or data. Inference can also refer to techniques for constructing higher-level events from a set of events and / or data. Such inference results in the construction of new events or actions from a set of observed events and / or stored event data, whether those events are closely related in time or not, and whether those events and data come from one or several event and data sources.

[0118] Also, the words "example" or "exemplary" are used herein to mean serving as an example, instance, or illustration. Any implementation described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other implementations. Rather, the use of the word exemplary is intended to present concepts in a concrete manner. The term "or" is used in its inclusive sense (and not in its exclusive sense) unless otherwise indicated. That is, unless otherwise indicated, "A or B" is intended to mean any of the natural inclusive permutations. That is, if X is A; X is B; or X is both A and B, then "X is A or B" is satisfied under any of the foregoing instances. Also, the articles "a" and "an" as used in this application and the appended claims should generally be construed to mean "one or more" unless specified otherwise or clear from context to be directed to a singular form. Thus, use of the articles "a" and "an" as well as "the" is not intended to be limiting.

[0119] Moreover, although one aspect can be disclosed using only one or more embodiments, such feature can also be combined with other one or more aspects, or used in combination with other explained features, even though the combination is not expressly disclosed. Furthermore, although the term "comprise" or variations such as "comprises" or "comprising" are used throughout to refer to a certain feature, integer, step or composition of matter, it will be understood that such feature, integer, step or composition of matter can also comprise one or more additional feature, integer, step or composition of matter, unless otherwise indicated.

Claims

1. A digital microphone device, comprising: a plurality of adaptive analog-to-digital converters (ADCs) configured to generate one of a plurality of digital audio signals having different scaling factors of an associated audio signal; an ADC range control component configured to adjust a gain of at least one of the plurality of adaptive ADCs based at least in part on a respective sound pressure level threshold sensed in at least one of the plurality of digital audio signals having different scaling factors; a plurality of gain compensation components respectively associated with one of the plurality of digital audio signals having different scaling factors, wherein the ADC range control component is further configured to continuously adjust a gain of at least one of the gain compensation components to compensate for a change in the gain of the at least one of the plurality of adaptive ADCs; and a glitch elimination component configured to minimize audible artifacts associated with the change in the gain of the at least one of the plurality of adaptive ADCs.

2. The digital microphone device of claim 1, further comprising: a multiplexing component configured to switch passing a digital audio signal associated with the at least one of the plurality of adaptive ADCs and another digital audio signal associated with another one of the plurality of adaptive ADCs.

3. The digital microphone device of claim 1, wherein, another one of the plurality of adaptive ADCs is configured to provide a low power audio signal relative to a power of the plurality of digital audio signals having different scaling factors.

4. The digital microphone device of claim 1, wherein, the plurality of adaptive ADCs are configured to be gain adjusted by the ADC range control component from one of a plurality of input sampling capacitance values of an associated one of the plurality of adaptive ADCs to another one of the plurality of input sampling capacitance values of the associated one of the plurality of adaptive ADCs in accordance with an ADC range control algorithm.

5. The digital microphone device of claim 1, wherein, the plurality of adaptive ADCs are further configured to be placed in a first low power mode.

6. The digital microphone device of claim 5, further comprising: a low power mode adaptive ADC of the plurality of adaptive ADCs configured to provide a second low power mode, wherein the plurality of adaptive ADCs other than the low power mode adaptive ADC are configured to be turned off to provide the second low power mode.

7. The digital microphone device of claim 1, wherein, the glitch elimination component is further configured to minimize audible artifacts by a glitch elimination algorithm based on the change in the gain of the at least one of the plurality of adaptive ADCs determined by the ADC range control component.

8. The digital microphone device of claim 7, wherein, the glitch elimination component is further configured to minimize audible artifacts by the glitch elimination algorithm comprising at least one of zero crossing detection, filtering, or signal prediction.

9. The digital microphone device of claim 1, wherein, the plurality of adaptive ADCs comprise a plurality of sigma delta modulators or a plurality of successive approximation ADCs configured as ADCs.

10. The digital microphone device of claim 9, further comprising: a plurality of digital audio filters respectively operably coupled to one of the plurality of sigma delta modulators configured as ADCs, configured to receive one of the plurality of digital audio signals having a different scaling factor of the associated audio signal, and configured to provide a plurality of filtered digital audio signals.

11. The digital microphone device of claim 10, wherein, The plurality of digital audio filters comprises at least one of a plurality of integer decimators or a plurality of low pass filters.

12. The digital microphone device of claim 1, further comprising: an output component configured to transmit a digital signal based on the plurality of digital audio signals, including at least one of a pulse density modulation (PDM) signal, an integrated inter-chip sound (I 2 S) signal, a time-division multiplexed signal, or a Soundwire signal.

13. The digital microphone device of claim 12, wherein, The output component comprises at least one of a non-linearity compensation component, a filter component, a digital gain adjustment component, or a signal shaper component.

14. A method for a digital microphone, comprising: generating a plurality of digital audio signals with a plurality of adaptive analog-to-digital converters (ADCs), the plurality of digital audio signals respectively having different scaling factors of an associated audio signal; adjusting a gain of at least one of the plurality of adaptive ADCs by an ADC range control component configured to adjust the gain based at least in part on a respective sound pressure level threshold sensed in at least one of the plurality of digital audio signals having a different scaling factor; adjusting the gain by a plurality of gain compensation components respectively associated with one of the plurality of digital audio signals having a different scaling factor, wherein the ADC range control component is further configured to continuously adjust the gain of at least one of the gain compensation components to compensate for a change in the gain of the at least one of the plurality of adaptive ADCs; and eliminating at least one glitch associated with the plurality of digital audio signals having a different scaling factor by a glitch elimination component configured to minimize audible artifacts associated with the change in the gain of the at least one of the plurality of adaptive ADCs.

15. The method of claim 14, further comprising: switching passing a digital audio signal associated with the at least one of the plurality of adaptive ADCs and another digital audio signal associated with another one of the plurality of adaptive ADCs.

16. The method of claim 14, wherein, The generating the plurality of digital audio signals comprises generating the plurality of digital audio signals with another one of the plurality of adaptive ADCs configured to provide a low power audio signal relative to a power of the plurality of digital audio signals having a different scaling factor.

17. The method of claim 14, wherein, The adjusting the gain of the at least one of the plurality of adaptive ADCs by the ADC range control component comprises adjusting the gain of the at least one of the plurality of adaptive ADCs by the ADC range control component from one of a plurality of input sample capacitance values of an associated one of the plurality of adaptive ADCs to another one of the plurality of input sample capacitance values of the associated one of the plurality of adaptive ADCs in accordance with an ADC range control algorithm.

18. The method of claim 14, further comprising: placing the plurality of adaptive ADCs in a first low power mode.

19. The method of claim 17, further comprising: placing the plurality of adaptive ADCs in a second low power mode includes selecting a low power mode adaptive ADC of the plurality of adaptive ADCs configured to provide the second low power mode, wherein the plurality of adaptive ADCs other than the low power mode adaptive ADC are configured to be turned off to provide the second low power mode.

20. The method of claim 14, wherein, eliminating at least one glitch associated with the plurality of digital audio signals having different scaling factors by the glitch elimination component includes eliminating at least one glitch in accordance with a glitch elimination algorithm based on the change in the gain of the at least one of the plurality of adaptive ADCs determined by the ADC range control component.

21. The method of claim 20, wherein, eliminating the at least one glitch includes eliminating the at least one glitch in accordance with the glitch elimination algorithm including at least one of zero crossing detection, filtering, or signal prediction.

22. The method of claim 14, wherein, generating the plurality of digital audio signals includes generating the plurality of digital audio signals with at least one of the plurality of adaptive ADCs including a plurality of sigma delta modulators or a plurality of successive approximation ADCs configured as ADCs.

23. The method of claim 22, further comprising: receiving the plurality of digital audio signals with a plurality of digital audio filters respectively operably coupled to one of the plurality of sigma delta modulators configured as ADCs, wherein the plurality of digital audio filters are configured to receive one of the plurality of digital audio signals having different scaling factors of the associated audio signals and are configured to provide a plurality of filtered digital audio signals.

24. The method of claim 23, wherein, receiving the plurality of digital audio signals with the plurality of digital audio filters includes receiving the plurality of digital audio signals with at least one of a plurality of integer decimators or a plurality of low pass filters.

25. The method of claim 14, further comprising: transmitting digital audio signals based on the plurality of digital audio signals, including at least one of transmitting pulse density modulated (PDM) signals, integrated inter-chip sound (I 2 S) signals, time division multiplexed signals, or Soundwire signals.

26. The method of claim 25, wherein, transmitting the digital signal includes transmitting the digital signal through at least one of a non-linearity compensation component, a filter component, a digital gain adjustment component, or a signal shaper component.

27. A digital microphone device, comprising: an adaptive analog-to-digital converter (ADC) configured to generate digital audio signals having different scaling factors of associated audio signals; an ADC range control component configured to adjust a gain of the adaptive ADC based at least in part on respective sound pressure level thresholds sensed in the digital audio signals having different scaling factors; a gain compensation component associated with the digital audio signals having different scaling factors, wherein the ADC range control component is further configured to continuously adjust a gain of the gain compensation component to compensate for a change in the gain of the adaptive ADC; and a glitch elimination component configured to minimize audible artifacts associated with the change in the gain of the adaptive ADC.

28. The digital microphone device of claim 27, wherein, the adaptive ADC is configured to be gain adjusted by the ADC range control component in accordance with an ADC range control algorithm by a change from one of a plurality of input sampling capacitance values of the adaptive ADC to another of the plurality of input sampling capacitance values of the adaptive ADC.

29. The digital microphone device of claim 27, wherein, The glitch elimination component is further configured to minimize audible artifacts through a glitch elimination algorithm based on the change in the gain of the adaptive ADC determined by the ADC range control component.

30. The digital microphone device of claim 29, wherein, The glitch elimination component is further configured to minimize audible artifacts through the glitch elimination algorithm including at least one of zero-crossing detection, filtering, or signal prediction.

31. The digital microphone device of claim 27, wherein, The adaptive ADC includes a sigma delta modulator or a successive approximation ADC configured as an ADC.

32. The digital microphone device of claim 31, further comprising: a digital audio filter operably coupled to the sigma delta modulator configured as the ADC, configured to receive the digital audio signal having different scaling factors of the associated audio signal, and configured to provide a filtered digital audio signal.

33. The digital microphone device of claim 32, wherein, The digital audio filter includes at least one of an integer down-sampler or a low pass filter.

34. The digital microphone device of claim 27, further comprising: an output component configured to transmit a digital signal based on the digital audio signal, including at least one of a pulse density modulation (PDM) signal, an integrated inter-chip sound (I 2 S) signal, a time-division multiplexed signal, or a Soundwire signal.

35. The digital microphone device of claim 34, wherein, The output component includes at least one of a non-linearity compensation component, a filter component, a digital gain adjustment component, or a signal shaper component.

36. A method for a digital microphone, comprising: generating a digital audio signal having different scaling factors of an associated audio signal with an adaptive analog-to-digital converter (ADC); adjusting a gain of the adaptive ADC by an ADC range control component configured to adjust a gain based at least in part on a respective sound pressure level threshold sensed in the digital audio signal having different scaling factors; adjusting a gain by a gain compensation component associated with the digital audio signal having different scaling factors, wherein the ADC range control component is further configured to continuously adjust a gain of the gain compensation component to compensate for a change in the gain of the adaptive ADC; and eliminating at least one glitch associated with the digital audio signal having different scaling factors by a glitch elimination component configured to minimize audible artifacts associated with the change in the gain of the adaptive ADC.

37. The method of claim 36, wherein, The adjusting a gain of the adaptive ADC by the ADC range control component includes adjusting a gain of the adaptive ADC by the ADC range control component from one of a plurality of input sampling capacitance values of the adaptive ADC to another of the plurality of input sampling capacitance values of the adaptive ADC in accordance with an ADC range control algorithm.

38. The method of claim 36, wherein, The eliminating at least one glitch associated with the digital audio signal having different scaling factors by the glitch elimination component includes eliminating at least one glitch in accordance with a glitch elimination algorithm based on the change in the gain of the adaptive ADC determined by the ADC range control component.

39. The method of claim 38, wherein, The eliminating the at least one glitch includes eliminating the at least one glitch in accordance with the glitch elimination algorithm including at least one of zero-crossing detection, filtering, or signal prediction.

40. The method of claim 36, wherein, The generating the digital audio signal includes generating the digital audio signal with the adaptive ADC including a sigma delta modulator or a successive approximation ADC configured as the ADC.

41. The method of claim 40, further comprising: receiving the digital audio signal with a digital audio filter operably coupled to the sigma delta modulator configured as the ADC, wherein the digital audio filter is configured to receive the digital audio signal with a different scaling factor of the associated audio signal and configured to provide a filtered digital audio signal.

42. The method of claim 41, wherein, The receiving the digital audio signal with the digital audio filter includes receiving the digital audio signal with at least one of an integer decimator or a low pass filter.

43. The method of claim 36, further comprising: transmitting a digital audio signal, including at least one of transmitting a pulse density modulated (PDM) signal, an integrated chip-to-chip sound (I 2 S) signal, a time division multiplexed signal, or a Soundwire signal based on the digital audio signal.

44. The method of claim 43, wherein, The transmitting the digital signal includes transmitting the digital signal through at least one of a non-linear compensation component, a filtering component, a digital gain adjustment component, or a signal shaper component.

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