TWI669513B - Electronic device and control method thereof - Google Patents

Abstract

An electronic device includes: a connector, a detector, an audio source, a signal generator, a switch, an amplifier, and a processor. The detector determines whether a headset is coupled to the connector. The signal generator generates a test signal, wherein the test signal includes an AC portion and a DC portion, and the DC portion is generated after the AC portion. The switch is switched between the audio source and the signal generator, wherein the switch selects the test signal as an input signal when the earphone is initially coupled to the connector. The amplifier amplifies the input signal to generate an amplified signal, wherein the amplified signal is transmitted to the connector and the earphone such that the earphone generates a feedback signal based on the amplified signal. The processor calculates an impedance value of one of the earphones based on the feedback signal.

Description

Electronic device and control method thereof

The present invention relates to an electronic device, and more particularly to an electronic device capable of detecting an impedance value of an earphone.

In the traditional design, when an external earphone (Earphone) is coupled to a system end, the system end usually transmits a direct current (DC) test signal to the earphone to estimate the impedance value of the earphone (Impedance Value). However, a pure DC test signal may cause the user wearing the headset to hear a larger noise (for example, "click"). In view of this, it is necessary to propose a new solution to overcome the problems faced by the prior art.

In an embodiment, the present invention provides an electronic device for detecting an impedance value of an earphone, and includes: a connector; a detector for determining whether the earphone is coupled to the connector; an audio source Generating a sound signal; a signal generator generating a test signal, wherein the test signal includes an alternating current portion and a direct current portion, and the direct current portion is generated after the alternating current portion; a switcher Switching between the audio source and the signal generator, wherein when the earphone is initially coupled to the connector, the switch selects the test signal as an input signal; an amplifier amplifies the input signal to generate a Amplify the signal, The amplified signal is transmitted to the connector and the earphone, so that the earphone generates a feedback signal according to the amplified signal; and a processor calculates the impedance value of the earphone according to the feedback signal.

In some embodiments, the alternating portion of the test signal is a sine wave and the frequency of the sine wave is greater than 20 kHz.

In some embodiments, the total length of time of the alternating portion of the test signal is at least 5 times the period length of the sine wave.

In some embodiments, the potential level of the DC portion of the test signal is equal to the highest potential level of the sine wave.

In some embodiments, after the processor calculates the impedance value of the earphone, the processor adjusts a gain ratio of the amplifier according to the impedance value of the earphone, and the switch updates and selects the sound signal as The input signal.

In another preferred embodiment, the present invention provides a control method, including the following steps: determining, by a detector, whether an earphone is coupled to a connector of an electronic device; generating an image by using an audio source a sound signal; a test signal is generated by a signal generator, wherein the test signal includes an alternating current portion and a direct current portion, and the direct current portion is generated after the alternating current portion; by a switcher, Switching between the audio source and the signal generator, wherein when the earphone is initially coupled to the connector, the switch selects the test signal as an input signal; and the input signal is amplified by an amplifier, Generating an amplified signal; transmitting the amplified signal to the connector and the earphone, such that the earphone generates a feedback signal according to the amplified signal; and calculating, by the processor, the earphone according to the feedback signal Impedance value.

In some embodiments, the controlling method further includes: after the processor calculates the impedance value of the earphone, adjusting, by the processor, a gain ratio of the amplifier according to the impedance value; and by using the switching The sound signal is updated and selected as the input signal.

100‧‧‧Electronic devices

110‧‧‧Connector

120‧‧‧Detector

130‧‧‧ audio source

140‧‧‧Signal Generator

150‧‧‧Switch

160‧‧‧Amplifier

170‧‧‧ processor

190‧‧‧ headphone

210‧‧‧Communication part of the test signal

215‧‧‧Sine wave

220‧‧‧ DC part of the test signal

DC‧‧‧ potential level of the DC part of the test signal

L1‧‧‧Inductors

The highest potential level of the MAX‧‧‧ sine wave

K‧‧‧Magnification

R1‧‧‧Resistors

SA‧‧‧Amplified signal

SF‧‧‧ feedback signal

SI‧‧‧ input signal

SS‧‧‧Sound signal

ST‧‧‧ test signal

T‧‧‧ cycle length

TL‧‧‧ total length of time

VSS‧‧‧ Ground potential

Z‧‧‧ impedance value

1 is a schematic view showing an electronic device and an earphone according to an embodiment of the invention.

2 is a waveform diagram showing test signals according to an embodiment of the present invention.

Figure 3 is a diagram showing an equivalent circuit diagram of a headphone according to an embodiment of the present invention.

Figure 4 is a flow chart showing a control method according to an embodiment of the present invention.

Figure 5 is a flow chart showing a control method according to another embodiment of the present invention.

In order to make the objects, features and advantages of the present invention more comprehensible, the specific embodiments of the invention are set forth in the accompanying drawings.

Certain terms are used throughout the description and claims to refer to particular elements. Those skilled in the art will appreciate that a hardware manufacturer may refer to the same component by a different noun. This specification and the scope of patent application do not use the difference in name as the means of distinguishing components, but the function of components. The difference is used as a criterion for differentiation. The words "including" and "including" as used throughout the specification and patent application are open-ended terms and should be interpreted as "including but not limited to". The term "substantially" means that within the acceptable error range, those skilled in the art will be able to solve the technical problems within a certain error range to achieve the basic technical effects. In addition, the term "coupled" is used in this specification to include any direct and indirect electrical connection means. Therefore, if a first device is coupled to a second device, the first device can be directly electrically connected to the second device, or indirectly connected to the second device via other devices or connection means. Two devices.

1 is a schematic diagram showing an electronic device 100 and an earphone 190 according to an embodiment of the invention. The earphone 190 can be selectively coupled to the electronic device 100, which can be regarded as an external device of the electronic device 100. The types and types of the electronic device 100 and the earphone 190 are not particularly limited in the present invention. For example, the electronic device 100 can be a smart phone, a tablet computer, a desktop computer, or a notebook computer, and the headset 190 It can be a wired headset or a wireless Bluetooth headset.

As shown in FIG. 1 , the electronic device 100 includes a connector 110 , a detector 120 , an audio source 130 , a signal generator 140 , and a switch . A Switch Element 150, an Amplifier 160, and a Processor 170. It should be understood that although not shown in FIG. 1 , the electronic device 100 may further include other components, such as: a battery module (Battery) Module), a Display Device, a Touch Control Module, a Speaker, or a Housing.

The electronic device 100 can be used to detect the Impedance Value Z of the earphone 190. The connector 110 may be one of the earphone jacks of the electronic device 100. The detector 120 is coupled to the connector 110 and can analyze signals from the connector 110. In detail, the detector 120 can be used to determine whether the earphone 190 is coupled to the connector 110 and when the earphone 190 is coupled to the connector 110. For example, when the earphone 190 is initially coupled to the connector 110 (or when the earphone 190 is initially inserted into the earphone jack), the detector 120 can generate a device presence signal to notify other components of the electronic device 100, currently There are cases where the earphone 190 is present.

The audio source 130 is for generating a sound signal SS. For example, the sound signal SS may include a music signal, a voice signal, or a mixed signal of the two. The signal generator 140 is for generating a test signal ST. 2 is a waveform diagram showing a test signal ST according to an embodiment of the present invention. As shown in FIG. 2, the test signal ST includes an alternating current (AC) portion 210 and a direct current (DC) portion 220, wherein the direct current portion 220 is generated after the alternating current portion 210. Such alternating current and direct current components of the test signal ST help to suppress the noise of the noise generated when the earphone 190 is coupled to the connector 110 and subjected to impedance testing.

The switch 150 can switch between the audio source 130 and the signal generator 140 to selectively couple the audio source 130 or the signal generator 140 to the amplifier 160. For example, the switch 150 can be a Single Pole Double Throw (SPDT) Switch. When the earphone 190 is initially coupled to the connector At 110 o'clock, the switch 150 can select the test signal ST of the signal generator 140 as one of the input signals SI of the amplifier 160. The amplifier 160 amplifies the input signal SI by a gain factor K to generate an amplified signal SA. Then, the amplified signal SA (that is, the amplified test signal ST) can be further transmitted to the connector 110 and the earphone 190, so that the earphone 190 can generate a feedback signal SF according to the amplified signal SA. For example, the feedback signal SF may include a voltage value and a current value returned by the earphone 190 when the amplified signal SA is applied to the earphone 190. Then, the feedback signal SF can be received by the connector 110, and the processor 170 can further calculate the impedance value Z of the earphone 190 according to the feedback signal SF. For example, the impedance value Z of the earphone 190 can be proportional to the ratio of the aforementioned voltage value to the aforementioned current value.

Please refer to Figure 2 again. In detail, the AC portion 210 of the test signal ST can be a sine wave (Sine Wave) 215, wherein the frequency of the sine wave 215 can be greater than 20 kHz, for example, 30 kHz or 40 kHz. The total length of time TL of the alternating current portion 210 of the test signal ST may be at least 5 times greater than the period length T of the sine wave 215. The potential level DC of the DC portion 220 of the test signal ST can be equal to the highest potential level MAX of the sine wave 215. In other words, the aforementioned parameter setting of the test signal ST can be as described in the following equations (1) to (4):

DC=MAX.................................................. .... (4) where "F" represents the frequency of the sine wave 215, "T" represents the period length T of the sine wave 215, and "TL" represents the total time length TL of the AC portion 210 of the test signal ST, "DC" Represents the potential level DC of the DC portion 220 of the test signal ST, "MAX" represents the highest potential level MAX of the sine wave 215.

In general, the large noise sound generated when the earphone 190 is inserted into the electronic device 100 is caused by the DC test signal applied to the earphone 190. To suppress this noise, the present invention proposes to replace the conventional conventional DC test signal with a test signal ST comprising an AC portion 210 and a DC portion 220. Since the frequency of the alternating portion 210 of the test signal ST is relatively high (eg, greater than 20 kHz), it will not be perceived by the human ear. In addition, after expiration of a suitable period of time (eg, after 5 times the period length T of the sine wave 215), the AC portion 210 of the test signal ST will be converted to the DC portion 220 to test the impedance value Z of the headphone 190. . At this time, regarding the voltage value and the current value of the earphone 190, the Steady State has been tended to be stable, so that the headphone 190 is less likely to generate noise. 3 is an equivalent circuit diagram showing an earphone 190 according to an embodiment of the present invention. As shown in FIG. 3, the earphone 190 can be analogized as a combination of an inductor (L1) and a resistor (Resistor) which are connected in series with the ground potential VSS. Initially, the transient current (Transient Current) of the inductor L1 of the earphone 190 may cause noise, but the transient current will naturally disappear after the total length of time TL of the AC portion 210. Therefore, the design of the present invention can effectively eliminate the non-ideal noise generated by the earphone 190 when performing impedance testing.

In some embodiments, the switch 150 can be combined with the amplifier 160 to form a Multi-Input and Single-Output Amplifier; in other embodiments, the detector 120 or (and) The signal generator 140 can be combined with the processor 170 to form a compound processor, neither of which affects the effects of the present invention.

After the processor 170 calculates the impedance value Z of the earphone 190, the processing The controller 170 can further adjust the gain magnification K of the amplifier 160 according to the impedance value Z of the earphone 190. For example, if the impedance value Z of the earphone 190 becomes larger, the gain magnification K of the amplifier 160 becomes larger; conversely, if the impedance value Z of the earphone 190 becomes smaller, the gain magnification K of the amplifier 160 becomes smaller. After the fine adjustment of the gain magnification K of the amplifier 160 is completed, the impedance test procedure for the earphone 190 has all been completed, and the earphone 190 can perform normal operation. For example, the switch 150 can switch to the audio source 130 and reselect the sound signal SS as the input signal SI of the amplifier 160 according to an instruction from the processor 170, so that the user can hear the updated amplified signal by wearing the earphone 190. SA (ie, the amplified sound signal SS, not the amplified test signal ST).

Figure 4 is a flow chart showing a control method according to an embodiment of the present invention. This control method can be applied to the aforementioned electronic device 100. First, in step S410, it is determined by a detector 120 whether an earphone 190 is coupled to one of the connectors 110 of the electronic device 100. If not, the program returns to step S410. If so, in step S420, a sound signal SS is generated by an audio source 130. Then, in step S430, a test signal ST is generated by a signal generator 140, wherein the test signal ST includes an AC portion 210 and a DC portion 220, and the DC portion 220 is generated after the AC portion 210. . In step S440, a switch 150 is used to switch between the audio source 130 and the signal generator 140. When the earphone 190 is initially coupled to the connector 110, the switch 150 selects the test signal ST as an input signal. SI. In step S450, the input signal SI is amplified by an amplifier 160 to generate an amplified signal SA. At step S460, the amplified signal SA is transmitted to the connector 110 and the earphone 190 such that the earphone 190 generates a feedback signal SF based on the amplified signal SA. Finally, in step S470, by a processor 170, The impedance value Z of the earphone 190 is calculated based on the feedback signal SF. It should be noted that the above steps need not be sequentially performed, and any of the features of the electronic device 100 of FIGS. 1-3 can be applied to the control method of FIG.

Figure 5 is a flow chart showing a control method according to another embodiment of the present invention. Figure 5 is similar to Figure 4. In the embodiment of FIG. 5, the control method further includes another step S480. That is, after the processor 170 calculates the impedance value Z of the earphone 190, the processor 170 adjusts the gain magnification K of the amplifier 160 according to the impedance value Z of the earphone 190, and updates the switch 150 by the switch 150. The sound signal SS is reselected as the input signal SI of the amplifier 160.

The present invention proposes a novel electronic device. By using a test signal including an alternating current portion and a direct current signal, the noise generated by the earphone coupled to the electronic device and performing the impedance test can be effectively eliminated. Compared with the conventional technology, the present invention has at least the advantages of low cost, low complexity, and better user experience, so it is suitable for various electronic devices.

It should be noted that the above-mentioned component parameters are not the limitations of the present invention. Designers can adjust these settings to suit different needs. The electronic device and control method of the present invention are not limited to the state illustrated in Figures 1-5. The present invention may include only any one or more of the features of any one or a plurality of embodiments of Figures 1-5. In other words, not all illustrated features must be implemented simultaneously in the electronic device and control method of the present invention.

The ordinal numbers in this specification and the scope of the patent application, such as "first", "second", "third", etc., have no sequential relationship with each other, and are only used to indicate that two are identical. Different components of the name.

Although the present invention has been disclosed above in the preferred embodiment, it is not The scope of the present invention is defined by those skilled in the art, and modifications and modifications may be made without departing from the spirit and scope of the invention, and the scope of the invention is defined by the scope of the appended claims. Prevail.

Claims (4)

An electronic device for detecting an impedance value of an earphone, and comprising: a connector; a detector for determining whether the earphone is coupled to the connector; an audio source for generating a sound signal; and a signal generator Generating a test signal, wherein the test signal includes an alternating current portion and a direct current portion, and the direct current portion is generated after the alternating current portion; a switch between the audio source and the signal generator Switching, wherein when the earphone is initially coupled to the connector, the switch selects the test signal as an input signal; an amplifier amplifies the input signal to generate an amplified signal, wherein the amplified signal is transmitted to The connector and the earphone enable the earphone to generate a feedback signal according to the amplified signal; and a processor to calculate the impedance value of the earphone according to the feedback signal; wherein the alternating portion of the test signal is a a sine wave having a frequency greater than 20 kHz; wherein the total length of the alternating portion of the test signal is at least 5 times the period length of the sine wave; The DC potential of the bit portion of the test signal is equal to the highest potential of the quasi-sine wave to the level. The electronic device of claim 1, wherein after the processor calculates the impedance value of the earphone, the processor adjusts a gain ratio of the amplifier according to the impedance value of the earphone, and the switching Update and select The sound signal is selected as the input signal. A control method includes the following steps: determining, by a detector, whether a headset is coupled to a connector of an electronic device; generating an audio signal by using an audio source; and generating a signal by using a signal generator a test signal, wherein the test signal includes an AC portion and a DC portion, and the DC portion is generated after the AC portion; and a switch is used between the audio source and the signal generator Switching, wherein when the earphone is initially coupled to the connector, the switch selects the test signal as an input signal; and the input signal is amplified by an amplifier to generate an amplified signal; the amplified signal is transmitted to The connector and the earphone enable the earphone to generate a feedback signal according to the amplified signal; and calculate, by the processor, the impedance value of the earphone according to the feedback signal; wherein the alternating portion of the test signal Is a sine wave, and the frequency of the sine wave is greater than 20 kHz; wherein the total length of the alternating portion of the test signal is at least 5 times the period length of the sine wave Wherein the test portion of the DC voltage signal is equal to the quasi-sine wave of the highest potential level. The control method of claim 3, further comprising: after the processor calculates the impedance value of the earphone, by using the processor, Adjusting a gain ratio of one of the amplifiers according to the impedance value; and updating, by the switch, the sound signal as the input signal.