CN114816314A

CN114816314A - Sensing device and master control device

Info

Publication number: CN114816314A
Application number: CN202111248323.9A
Authority: CN
Inventors: 蔡仲航; 叶宜璟; 李�杰
Original assignee: Realtek Semiconductor Corp
Current assignee: Realtek Semiconductor Corp
Priority date: 2021-01-28
Filing date: 2021-10-26
Publication date: 2022-07-29
Anticipated expiration: 2041-10-26
Also published as: CN114816314B; TWI774586B; TW202231038A

Abstract

A sensing device and a master device are provided. The sensing device includes: a sensing information transmission circuit, a control information slave circuit and a mode switching circuit. The sensing information transmission circuit is used for converting sensing information into a transmission signal conforming to the signal format of a first transmission protocol according to the first transmission protocol. The control information slave circuit is used for converting a received signal received from a signal transmission interface into control information according to a second transmission protocol, so as to set the sensing device. The mode switching circuit is used for starting one of the sensing information transmission circuit and the control information slave circuit according to a signal on a clock pulse channel, a signal on a data channel or a signal on a power supply rail of the sensing device on the signal transmission interface so as to transmit or receive signals through the signal transmission interface.

Description

Sensing device and master control device

Technical Field

The present invention relates to signal transmission, and more particularly, to a transmission control architecture for transmitting signals of multiple transmission protocols between a host control device and a sensing device using a single signal transmission interface.

Background

Today's digital microphones, such as: digital Micro-electro-mechanical Systems (MEMS) microphones typically rely on a Pulse-Density Modulation (PDM) interface to transmit audio signals. The PDM interface generally has a 1-bit data channel and a clock channel for signal transmission in serial form. However, the PDM interface itself does not have a control channel, and cannot transmit the control parameters related to the digital microphone, so that the digital microphone cannot change its acoustoelectric characteristics after being shipped from the factory, for example: sampling rate, sensitivity, Acoustic Overload Point (AOP), or filter settings, among others. Therefore, if the digital microphone needs to be adjusted, a transmission protocol with an in-band control (in-band control) such as a MIPI Audio interface (MIPI SoundWire) or/HD-Audio interface is used, or a signal pin is added. However, both of these approaches increase system cost and circuit complexity.

Disclosure of Invention

In view of the above, an objective of the present invention is to provide an integrated data/control interface method, which uses an existing signal transmission interface for sensing information to transmit sensing information and control information respectively in a time-division multiplexing manner, so as to control and read sensing information from a sensing device, thereby implementing setting/characteristic adjustment of the sensing device. The architecture of the invention effectively integrates different signal transmission interfaces, thereby not causing the cost to be greatly improved.

An embodiment of the present invention provides a sensing device. The sensing device includes: a sensing information transmission circuit, a control information slave circuit and a mode switching circuit. The sensing information transmission circuit is used for converting sensing information into a transmission signal conforming to the signal format of a first transmission protocol according to the first transmission protocol. The control information slave circuit is used for converting a receiving signal received from a signal transmission interface into control information according to a second transmission protocol, so as to set the sensing device. The mode switching circuit is coupled to the sensing information transmitting circuit and the control information slave circuit, and is configured to activate one of the sensing information transmitting circuit and the control information slave circuit to transmit or receive a signal through the signal transmission interface according to a signal on a clock channel, a signal on a data channel, or a signal on a power rail of the sensing device on the signal transmission interface.

An embodiment of the present invention provides a host device. The master control device comprises: a sensing information receiving circuit, a control information main circuit and a mode switching circuit. The sensing information receiving circuit is used for converting a received signal received from a signal transmission interface into sensing information according to a first transmission protocol. The control information main circuit is used for converting control information into a transmission signal conforming to the signal format of a second transmission protocol according to the second transmission protocol. The mode switching circuit is coupled to the sensing information receiving circuit and the control information main circuit, and is configured to adjust a signal on a clock channel, a signal on a data channel, or a signal on a power rail of the sensing device according to an operation mode of the main control device, and control one of the sensing information receiving circuit or the control information main circuit to receive or transmit a signal using the signal transmission interface.

Drawings

Fig. 1 is a schematic diagram illustrating an architecture of a master device and a sensing device according to an embodiment of the invention.

Fig. 2 shows a detailed architecture diagram of the mode detection circuit in an embodiment of the present invention.

Fig. 3 shows a signal timing chart in the embodiment of the present invention.

Fig. 4 shows a schematic diagram of hysteresis control in an embodiment of the invention.

FIG. 5 is a detailed architecture diagram of the host device controlling and accessing multiple sensing devices simultaneously according to an embodiment of the present invention.

Detailed Description

In the following description, numerous specific details are set forth in order to provide a thorough understanding of embodiments of the invention to the reader. However, those skilled in the art will understand how to implement the invention without one or more of the specific details, or with other methods or elements or materials, etc. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the invention.

Reference in the specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the invention. Thus, the appearances of the phrase "in one embodiment" appearing in various places throughout the specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics described above may be combined in any suitable manner in one or more embodiments.

Referring to fig. 1, a main control device and a sensing device of a signal transmission interface according to an embodiment of the present invention are shown. The master control device 100 can communicate with one or more sensing devices 200 through the signal transmission system of the present invention, so as to adjust the settings of the one or more sensing devices 200 and read the sensing data. In some embodiments, the signal transmission interface 300 comprises at least a first channel 310 and a second channel 320. The first channel 310 may be used for transmitting a clock signal, and the second channel 320 may be used for transmitting a data signal, but not limited thereto.

The master control device 100 includes a sensing information receiving circuit 110, a control information main circuit 120, and a mode switching circuit 130. The sensing information receiving circuit 110 is configured to convert the signal received from the second channel 320 into specific sensing information, such as audio information, vibration information, pressure information, optical information, or temperature information, based on the clock signal on the first channel 310 according to a first transmission protocol. In one embodiment, the first transmission protocol may be a Pulse Density Modulation (PDM) based transmission protocol. The control information master circuit 120 is configured to send control information to the sensing device 200 via at least one of the first channel 310 or the second channel 320 according to a second transmission protocol. Wherein the second transmission protocol may be a synchronous transmission protocol or a non-synchronous transmission protocol. For example, the synchronous transport protocol may be I ² C or Serial Peripheral Interface (SPI) protocol, and the non-synchronous transmission protocol may be a universal non-synchronous transmission protocolA Universal Asynchronous Receiver/Transmitter (UART) or a single wire (1-wire) protocol. When the second protocol is synchronous, the control information master circuit 120 sends a clock signal over the first channel 310 and control information over at least the second channel 320 (multiple non-clock channels may be required for communication depending on the requirements of the transmission protocol). When the second transmission protocol is a non-synchronous transmission protocol, the control information main circuit 120 may transmit the control information through one of the first channel 310 or the second channel 320 (e.g., 1-wire or UART single-ended transmission protocol), or both (e.g., UART differential transmission protocol). The mode switching circuit 130 can switch the usage rights of the sensing information receiving circuit 110 and the control information main circuit 120 for the first channel 310 and the second channel 320 according to the requirement of the master device 100. In various embodiments of the present invention, the mode switching circuit 130 may change the frequency of the signal on the first channel 310, the signal characteristic on the second channel 320, or the voltage level on the power rail 400, so as to notify the sensing device 200 in advance that the main control device 100 enters a set adjustment mode and the control information main circuit 120 transmits the control information using the signaling interface 300, or that the main control device 100 enters a sensing information reading mode and the sensing information receiving circuit 110 receives the sensing information using the signaling interface 300. In one embodiment, when the control information main circuit 120 intends to transmit control information to the sensing device 200 through the signal transmission interface 300, the mode switching circuit 130 may transmit a signal with a frequency lower than a threshold value on the first channel 310, or raise the voltage level on the power rail 400. In this way, the sensing device 200 can determine the transmission signal on the signal transmission interface 300 as the control information, so as to call the corresponding circuit module to process the signal on the channel. On the contrary, when the control information main circuit 120 wants to receive the sensing information through the signal transmission interface 300, the mode switching circuit 130 may transmit a signal with a frequency higher than the threshold value on the first channel 310, or decrease the voltage level on the power rail 400, so that the sensing device 200 calls the corresponding circuit module to transmit the sensing information. Please note that the above-mentioned methodThe formula is merely one embodiment of the present invention, which is suitable for the base clock of the first transmission protocol (e.g., PDM) being higher than that of the second transmission protocol (e.g., I) ² C) The base clock of (2). In other embodiments, if the basic clock of the first transmission protocol is lower than the basic clock of the second transmission protocol, the sensing device 200 can be informed about the switching of the operation mode in the opposite way. For example, before transmitting the control information, the mode switching circuit 130 may transmit a signal with a frequency higher than a threshold value on the first channel 310, or decrease the voltage level on the power rail 400, so that the sensing device 200 can sufficiently determine the transmission signal on the signal transmission interface 300 as the control information. Conversely, before receiving the sensing information, the mode switching circuit 130 may transmit a signal with a frequency lower than the threshold value on the first channel 310, or increase the voltage level on the power rail 400, so that the sensing device 200 calls the corresponding circuit module to transmit the sensing information. In other words, in the embodiment of the invention, whether the master device 100 is in the set adjustment mode or the sensed information reading mode can be reflected according to the high-low relationship between the frequency of the signal on the first channel 310 and the frequency threshold, or the high-low relationship between the voltage level on the power rail 400 and the voltage threshold.

In addition to the above, in other embodiments of the present invention, the master device 100 may also be enabled to notify the sensing device 200 of the mode switching by the signal feature on the second channel 320. For example, the mode switching circuit 130 may transmit a signal with a specific pattern (pattern) to the sensing device 200 on the second channel 320 within a specific time interval to inform the sensing device 200 that the current operation mode of the master device 100 is suitable for responding. For example, the encoding/decoding rules and the signal patterns can be preset/agreed between the master device 100 and the sensing device 200. When the sensing device 200 decodes the packet from the host 100, and the content of the decoded packet corresponds to a predetermined simple signal content or a series of consecutive signal contents (for example, but not limited to, the signal contents show consecutive BA (before being converted into binary bits) …, or a specific signal pattern such as 11011100), the sensing device 200 may determine the transmission signal on the signal transmission interface 300 as the control information, so as to call the corresponding circuit module to process the signal on the second channel 320.

The sensing device 200 includes a sensing information transmitting circuit 210, a control information slave circuit 220, and a mode switching circuit 230. The sensing information transmitting circuit 210 is configured to convert the sensing signal generated by the sensing module 240 into a data signal on the second channel 320 based on the clock signal on the first channel 310 according to the first transmission protocol, and transmit the data signal to the host device 100. In one embodiment, the sensing module 240 (when the sensing device 200 is a digital microphone) may include an acousto-electric conversion device, an analog-to-digital converter, a signal processing circuit, and the like. In another embodiment, the sensing module 240 (for example, when the sensing device 200 is a temperature sensing device) may include a thermoelectric conversion device, an analog-to-digital converter, a signal processing circuit, etc., but is not limited thereto. In addition, in further embodiments of the present invention, the sensing module 240 may also be a vibration sensor, a pressure sensor or an optical sensor. Furthermore, the control information slave circuit 220 is used for converting the signal received from at least one of the first channel 310 or the second channel 320 into the control information according to the second transmission protocol, so as to perform setting adjustment on the sensing module 240 or other circuit elements in the sensing apparatus 200. The setting parameters used by one or more components of the sensing module 240 or the sensing device 200 can be adjusted by the control information. In one embodiment, the setting parameters may include (but are not limited to): sampling rate, sensitivity, gain control, Acoustic Overload Point (AOP), or filter settings, etc. Furthermore, the mode switching circuit 230 includes a mode detection circuit 232 and a mode control circuit 234. The mode detection circuit 232 can determine that the current operation mode of the main control device 110 is the setting adjustment mode or the sensing information reading mode according to the signal frequency on the first channel 310 or the voltage level on the power rail 400. The mode control circuit 234 controls the sensing information transmitting circuit 210 and the control information slave circuit 220 to transmit or receive signals through the signal transmission interface 300 according to the determination result of the mode detection circuit 232.

In an embodiment of the present invention, a technique of hysteresis control is also added for the switching of the modes, thereby ensuring that the control information transmitted by the master control device 100 is not missed by the sensing devices 200. For the details of this feature, please further refer to the architecture diagram shown in fig. 2 and the timing diagram shown in fig. 3. First, as shown in fig. 2, the mode detection circuit 232 of the sensing device 200 further includes a static detection unit 2321 and a frequency detection unit 2322. Furthermore, as shown in fig. 3, before the master control device 100 enters the setting adjustment mode or the sensed information reading mode, the mode switching circuit 130 is required to transmit a dc signal through the first channel 310, where the dc signal may have a logic high level or a logic low level, and after the static detection unit 2321 detects that the signal on the first channel 310 maintains the dc state for a period of time (state a), it is determined that the master control device 100 enters the setting adjustment mode (state B), and further the mode control circuit 234 is required to perform mode switching, so that the sensing device 200 enters the setting adjustment mode, and the control information slave circuit 220 is activated (state C). Thereafter, the control information master circuit 120 transmits the control information in the signal format of the second transmission protocol through the first channel 310 and the second channel 320 (state D). When the control information master circuit 120 completes the transmission of the control information, the mode switching circuit 130 transmits the dc signal on the first channel 310 again (state E). At this time, the frequency detecting unit 2322 does not detect that the frequency reaches the predetermined threshold, which generates a hysteresis effect, and determines that the master control device 100 is still in the setting adjustment mode (state F), so that the mode control circuit 234 continues to maintain the setting adjustment mode and continuously activates the control information slave circuit 220 (state G). Thereafter, when the master device 100 intends to start reading the sensing information, the mode control circuit 234 enables the sensing information receiving circuit 110 to send out the clock signal (state H) conforming to the first transmission protocol on the first channel 310. At this time, the frequency detecting unit 2322 detects that the frequency of the signal on the first channel 310 is greater than a frequency threshold TH (e.g., 400K Hz), thereby determining that the master control device 100 switches the mode to the sensing information reading mode (state I), and further requesting the mode control circuit 234 to activate the sensing information transmitting circuit 210 (state J). Then, the sensing information transmitting circuit 210 transmits the sensing information generated by the sensing module 240 to the host device 100 through the second channel 320 in a format compatible with the second transmission protocol (state K). However, in the sensing information reading mode, if the frequency detection unit 2322 detects that the frequency of the signal on the first channel 310 is lower than the frequency threshold TH (state L, state M), since the static detection unit 2321 does not detect the dc state on the first channel 310, the mode switching circuit 230 does not immediately let the mode control circuit 234 start the control information slave circuit 220, enter the setting adjustment mode, and does not end the sensing information reading mode. Instead, it is determined that the master control device 100 enters the setting adjustment mode only when the static detection unit 2321 detects that the signal on the first channel 310 maintains the dc state, so that the mode control circuit 234 starts the control information slave circuit 220. As for the above mode switching details, it can be further understood from the schematic diagram shown in fig. 4, wherein in the setting adjustment mode, the frequency needs to be increased to be higher than the threshold value TH to switch to the sensing information reading mode. However, once the frequency is lower than the threshold TH, the mode is not switched to the sensing information reading mode immediately, but is switched to the sensing information reading mode when the frequency is zero (dc state).

FIG. 5 further shows the detailed architecture of a master device controlling and accessing multiple sensing devices simultaneously according to an embodiment of the present invention. As shown, the master device 100 controls and accesses the sensing devices 200_1 to 200_3 through the first channel 310, the second channel 320 and the third channel 330. Please note that, in the embodiment, the number of sensing devices that the master control device 100 can access simultaneously is not limited in the present invention. The master control device 100 mainly includes a master control circuit 150, one or more sensing information receiving circuits 110_1 to 110_3, control information main circuits 120_1 to 120_3, multiplexers 161 to 169, and logic control circuits 171 to 173. In the embodiment, the control information main circuits 120_ 1-120 _3 are substantially I ² C main circuit according to I ² C transport protocol to control sensingDevices 200_1 to 200_ 3. Therefore, the multiplexers 161-162, 164-165, 167-168, logic control circuits 171-173, and resistors 181-186 are designed to satisfy I ² C required for transmission protocol, signals on the channel are pulled up or pulled down (due to I) ² C the main circuit adopts an open drain structure). Accordingly, in other embodiments of the present invention, if the control information main circuits 120_1 to 120_3 are not I ² C main circuit, the circuit elements described above can be omitted.

The host circuit 150 can determine the operation mode of the host device 100 as a setting adjustment mode or a sensing information reading mode. The master control circuit 105 determines, through the control multiplexer 163, which of the sensing information receiving circuit 110_1 and the control information main circuit 120_1 generates the clock signal, which can be transmitted to the clock channel (i.e., the first channel) 310 through the clock pad 191. In the setting adjustment mode, the multiplexer 163 allows the clock signal generated by the main circuit 120_1 to be transmitted to the clock channel 310 and received by the sensing devices 200_1 to 200_ 3. Meanwhile, the signals generated by the control information main circuits 120_2 and/or 120_3 can be transmitted to the

data channels

320 and 330 through the

data pads

192 and 193. The data signals include specific control information, such as device ID and control parameters. Once the mode detection circuits 232_ 1-232 _3 in the sensing devices 200_ 1-200 _3 detect that the signal of the clock channel 310 is in the DC state, the mode is switched to the setting adjustment mode, and the slave circuit (i.e. I) for controlling information is activated ² C slave) 220_ 1-220 _3, which receive signals on

data channels

320 and 330. The sensing devices 200_1 to 200_3 selectively adjust the setting parameters according to the device ID in the signal. In addition, the main control circuit 150 can switch the

multiplexers

166 and 169 such that the control information main circuits 120_2 and/or 120_3 can receive signals on the

data channels

320 and 330 from the

data pads

192 and 193, for example, parameter setting results returned by the sensing devices 200_1 to 200_ 3.

On the other hand, in the sensing information reading mode, the multiplexer 163 allows the clock signal generated by the sensing information receiving circuit 110_1 to be transmitted to the clock channel 310 through the clock pad 191 and received by the sensing devices 200_1 to 200_ 3. The mode detection circuits 232_1 to 232_3 in the sensing devices 200_1 to 200_3 detect that the signal frequency of the clock channel 310 is greater than the threshold value TH, thereby switching the mode to the sensing information reading mode and activating the sensing information transmission circuits 210_1 to 210_ 3. The sensing information transmission circuits 210_1 to 210_3 transmit the sensing information generated by the sensing devices 200_1 to 200_3 back to the host device 100 through the

data channels

320 and 330. At this time, by switching the

multiplexers

166 and 169, the sensing information receiving circuits 110_2 and/or 110_3 can receive signals from the

data channels

320 and 330 through the

data pads

192 and 193, so as to obtain the sensing information returned by the sensing devices 200_1 to 200_ 3. Please note that, in the present embodiment, the main control device 100 includes sensing information receiving circuits 110_1 to 110_3 and control information main circuits 120_1 to 120_ 3. However, in other embodiments of the present invention, part of the sensing information receiving circuit or the control information main circuit may be integrated into the same one. For example, the control information main circuits 120_1 to 120_3 can be integrated into one and the sensing information receiving circuits 110_1 to 110_3 can be integrated into two.

Furthermore, although in the above embodiments, the mode detection circuit 232 and the mode control circuit 234 in the sensing device 200 perform mode detection and switching based on the frequency of the signal on the clock channel 310. However, in other embodiments of the present invention, the mode detection circuit 232 and the mode control circuit 234 in the sensing device 200 can also perform mode detection and switching based on the voltage level of the power rail 400. For example, the mode switching circuit 130 in the host 100 may increase the voltage level of the power rail 400 to 2.7V when the host 150 determines to transmit the control information, and decrease the voltage level of the power rail 400 to 1.8V when determining to receive the sensing information. Accordingly, the mode detection circuit 232 and the mode control circuit 234 in the sensing device 200 can determine when to sense the information transmitting circuit 210 or activate the control information slave circuit 220 according to the voltage level of the power rail 400.

To sum up, the present invention provides a signal transmission architecture for integrating sensing information transmission/control information transmission, which allows a single signal transmission to be connected toThe ports support signals of multiple transport protocols. PDM-based transmission protocols, such as those previously described, for transmitting sensed information, and I for transmitting control information ² A C protocol, an SPI protocol, a UART protocol, or a 1-wire protocol. Therefore, the invention can control and read the sensing information of the sensing device without greatly increasing the hardware cost and the circuit complexity, thereby realizing the setting/characteristic adjustment of the sensing device.

The above description is only a preferred embodiment of the present invention, and all equivalent changes and modifications made in accordance with the claims of the present invention should be covered by the present invention.

[ notation ] to show

100 master control device

110. 110_1 to 110_3 sensing information receiving circuit

120. 120_1 ~ 110_3 control information main circuit

130 mode switching circuit

150 main control circuit

161 to 169 multiplexer

171 to 173 logic control circuit

181-186 resistors

191 clock pad

192. 193 data pad

200. 200_1 to 200_3 sensing device

210. 210_1 to 210_3 sensing information transmission circuit

220. 220_ 1-220 _3 control information slave circuit

230 mode switching circuit

232 mode detection circuit

2321 static detection unit

2322 frequency detection unit

234 mode control circuit

240 sensing module

300 signal transmission interface

310 clock channel

320. 330 data channel

400 power rails.

Claims

1. A sensing device comprising:

a sensing information transmission circuit for converting a sensing information into a transmission signal conforming to a signal format of the first transmission protocol according to a first transmission protocol;

a control information slave circuit for converting a received signal received from a signal transmission interface into a control information according to a second transmission protocol, thereby setting the sensing device; and

a mode switching circuit, coupled to the sensing information transmission circuit and the control information slave circuit, for transmitting signals according to a clock channel, a data channel or a signal of the sensing device on the signal transmission interface A signal on a power rail activates one of the sensing information transmission circuit and the control information slave circuit, causing the one of the sensing information transmission circuit and the control information slave circuit to signal through the signal transmission interface transmit or receive.

2. The sensing device according to claim 1, wherein the sensing device is a digital MEMS microphone, a vibration sensor, a pressure sensor, an optical sensor or a temperature sensor, and The sensing information is an audio information, a vibration information, a pressure information, an optical information or a temperature information.

3. The sensing device of claim 1, wherein the first transmission protocol is a pulse density modulation based transmission protocol.

4 . The sensing device of claim 1 , wherein the second transmission protocol is an I ² C protocol, a serial peripheral interface protocol, a general asynchronous transceiver protocol, or a single wire protocol. 5 .

5. The sensing device of claim 1, wherein the mode switching circuit comprises:

a mode detection circuit, coupled to the clock channel or the power rail, for generating a detection result according to the signal on the clock channel or the signal on the power rail; and

a mode control circuit, coupled to the sensing information transmission circuit, the control information slave circuit and the mode detection circuit, for enabling one of the sensing information transmission circuit and the control information slave circuit according to the detection result .

6. The sensing device according to claim 5, wherein when the detection result indicates that the frequency of the signal on the clock channel is higher than a first threshold value, when the signal on the data channel corresponds to a signal characteristic, or When the voltage level of the signal on the power rail is lower than a second threshold, the mode switching circuit activates the sensing information transmission circuit; and when the detection result indicates that the frequency of the signal on the clock channel is lower than the first threshold When a threshold value or the voltage level of the signal on the power rail is higher than the second threshold value, the mode switching circuit activates the control information slave circuit.

7 . The sensing device according to claim 6 , wherein when the sensing information transmission circuit is activated, the mode switching circuit will activate the control only when the signal on the clock channel maintains a DC state. 8 . information from the circuit.

8. The sensing device of claim 5, wherein the detection result indicates that the frequency of the signal on the clock channel is higher or lower than a first threshold value, and the decoded content of the signal on the data channel matches a signal The feature or the voltage level of the signal on the power rail is compared with a second threshold, and the mode switching circuit determines to activate the sensing information transmission circuit or the control information slave circuit according to the detection result.

9. A main control device, comprising:

a sensing information receiving circuit for converting a received signal received from a signal transmission interface into sensing information according to a first transmission protocol;

a control information main circuit for converting a control information into a transmission signal conforming to a signal format of the second transmission protocol according to a second transmission protocol; and

a mode switching circuit, coupled to the sensing information receiving circuit and the control information main circuit, for adjusting a signal on a clock channel and a data channel on the signal transmission interface according to an operation mode of the main control device The signal of , or a signal on a power rail of a sensing device, controls one of the sensing information receiving circuit or the control information main circuit to use the signal transmission interface for signal reception or transmission.

10. The main control device according to claim 9, wherein the sensing device is a digital MEMS microphone, a vibration sensor, a pressure sensor, an optical sensor or a temperature sensor, and The sensing information is an audio information, a vibration information, a pressure information, an optical information or a temperature information.