TWI720467B - Switch device with switch debouncing - Google Patents

Abstract

A switch device with switch debouncing is provided. The switch device has a contact switch, a transmission unit and a processing unit. The contact switch triggers an electronic signal when being operated, the transmission unit is connected to a computer host, the processing unit outputs a corresponding switch signal when the contact switch is operated, times a threshold time, stops determining whether the contact switch is operated again, and recover to determining whether the contact switch is operated after the threshold time elapsed. The present disclosed example can eliminate a delay of triggering switch, and suppress the contact bounce noise.

Description

Switch device with bounce noise suppression function

The invention relates to a switch device, in particular to a switch device with a function of suppressing bounce noise.

Existing switch devices (such as keyboard keys or buttons of electronic devices) mostly trigger electrical signals through the contact of multiple electronic contacts. The above-mentioned triggering method will generate contact bounce noise at the moment of contact of the electronic contact. The above-mentioned contact bounce noise will cause the switch device to misjudge the button state and output an incorrect switch signal.

Please refer to FIG. 10, which is a schematic diagram of monitoring electrical signals of a contact switch in the prior art. As shown in the figure, when the user presses the button (time point T0), the electric signal of this button will immediately rise to a high level and trigger a series of contact bounce noises (that is, the electric signal between time point T0 and time point T1) ).

Moreover, when the user releases the button (time point T3), the electrical signal of the button will immediately drop to a low level and trigger a series of contact bounce noises (ie, electrical signals between time point T3 and time point T4).

The aforementioned contact bounce noise will cause the switch device to misjudge that the button is continuously released and pressed in a short period of time, and continuously output the button's press signal and release signal (that is, the wrong switch signal) in a short period of time, causing the user inconvenient.

In order to suppress the above-mentioned contact bounce noise and avoid outputting an erroneous switching signal, a technology for suppressing the bounce noise has been proposed.

Specifically, the existing technology for suppressing bounce noise is to continuously monitor the potential of the electrical signal after the user presses the button (time point T0), and start to count the preset stabilization time when the potential remains stable (time point T1) ( For example, 4ms), when the potential maintains a stable state and reaches the preset stable time (time point T2), the pressing signal of the button is output.

In addition, when the user releases the button (time point T3), the existing technology for suppressing bounce noise will also continue to monitor the electrical signal's potential, and start timing the preset stable time when the potential remains stable (time point T4) ( For example, 4ms), the release signal of this button is output when the potential maintains a stable state and reaches the preset stable time (time point T5).

The existing suppression of bounce noise mainly has two deficiencies: "trigger delay time is too long" and "trigger delay time is not fixed".

Regarding the trigger delay time is too long, when the user presses/releases the button, the existing technology for suppressing bounce noise must maintain a stable potential for a preset stable time before outputting the corresponding press/release signal (take Figure 10 as an example, The press delay is 12ms, and the release delay is 11ms).

Regarding the trigger delay time is not fixed, as the electronic contact ages, the duration of the aforementioned contact bounce noise may increase. This makes the existing technology to suppress bounce noise need to spend more time waiting for the potential to maintain a stable state, which makes the trigger The delay time increases. In addition, due to the different states of the electronic contacts of different keys (that is, the duration of the contact bounce noise is different), the existing techniques for suppressing bounce noise will cause the trigger delay time of different keys to be different, making it difficult for users to adapt to different keys. Different trigger delays.

In view of this, there is an urgent need for a solution to the above technical problems to be proposed.

The invention provides a switch device with the function of suppressing bounce noise, which can trigger the switch signal in real time and suppress the bounce noise.

In one embodiment, a switch device with bounce noise suppression function includes a contact switch, a transmission unit, and a processing unit electrically connecting the contact switch and the transmission unit. The contact switch triggers an electrical signal when it accepts an operation. The transmission unit is used to connect the host computer. When the processing unit judges that the contact switch is operated according to the electrical signal, it immediately outputs the switch signal corresponding to the electrical signal through the transmission unit, timings the critical time and stops determining whether the contact switch is operated again within the critical time, and the critical time elapses After that, continue to determine whether the contact switch is operated again based on the electrical signal.

The present invention can eliminate the delay of button triggering and suppress the bounce noise caused by button triggering, thereby improving user experience.

1: Switch device

10: Processing unit

11: Contact switch

12: Transmission unit

13: switch array

14: circuit board

15: Indicating unit

2: Computer host

30: keycap

31: Axle structure

32: switch housing

320: upper shell

321: lower shell

33: Reset component

34: The first conductive sheet

35: second conductive sheet

40: The first conductive sheet

400: first contact

41: second conductive sheet

410: second contact

42: barrier film

43: positioning hole

S10-S16: Monitoring and suppression steps

S20-S22: Manual adjustment steps

S30-S34: Automatic adjustment procedure

S0-S3: point in time

T0-T5: point in time

FIG. 1 is a structural diagram of a switch device according to an embodiment of the present invention; FIG. 2 is a structural diagram of a switch device according to another embodiment of the present invention; FIG. 3 is a first embodiment of the present invention to suppress bounce noise Fig. 4 is a flowchart of the manual adjustment of the critical time according to the second embodiment of the present invention; Fig. 5 is a flowchart of the automatic adjustment of the critical time according to the third embodiment of the present invention; Fig. 6 is a flowchart of the present invention Fig. 7A is a schematic cross-sectional view of the contact switch of Fig. 6 in a released state; Fig. 7B is a schematic cross-sectional view of the contact switch of Fig. 6 in a pressed state; Fig. 8A shows A schematic cross-sectional view of the contact switch of an embodiment of the invention in a released state; FIG. 8B is a schematic cross-sectional view of the contact switch of FIG. 8A in a pressed state; 9 is a schematic diagram of monitoring electrical signals of a contact switch according to an embodiment of the present invention; and FIG. 10 is a schematic diagram of monitoring electrical signals of a contact switch in the prior art.

The technical solutions of the present invention will be described in detail below in conjunction with the drawings and specific embodiments to further understand the purpose, solutions and effects of the present invention, but not as a limitation of the scope of the attached patent application of the present invention.

First, please refer to FIG. 1, which is a structural diagram of a switch device according to an embodiment of the present invention. As shown in the figure, the present invention provides a switch device 1 which mainly includes at least one contact switch 11, a transmission unit 12, and a processing unit 10 electrically connected to the contact switch 11 and the transmission unit 12.

The contact switch 11 (such as a lever switch, key, button, or other digital switch) is used to accept user operations (such as pressing or releasing operations), and trigger the corresponding electrical signals when accepting user operations (such as changing electrical signals) Potential).

The transmission unit 12 is used to wire/wirelessly connect an external computer host 2 (such as a mobile device, a notebook computer, a desktop computer, etc.) for signal transmission. Specifically, the transmission unit 12 can be a wireless transmission module (such as a Bluetooth wireless transmission module or an infrared wireless transmission module), and can directly establish a wireless connection with the computer host 2, or connect to the computer host 2 in a detachable manner. The wireless dongle establishes a wireless connection to connect to the host computer 2. Alternatively, the transmission unit 12 can be detachably connected to the computer host 2 via a transmission line (such as a USB transmission line).

The processing unit 10 is used to control the switch device 1. Specifically, the processing unit 10 continuously monitors whether the contact switch 11 triggers an electrical signal, and receives the electrical signal triggered by the contact switch 11 When the signal is displayed, the corresponding off signal is output to the computer host 2 through the transmission unit 12, so that the computer host 2 executes the corresponding function (such as inputting the corresponding character symbol).

Please continue to refer to FIG. 2, which is a structural diagram of a switch device according to another embodiment of the present invention. In this embodiment, the switch device 1 (such as a keyboard) further includes a switch array 13 and a circuit board 14. The switch array 13 includes a plurality of contact switches 11 (such as a plurality of buttons).

In addition, the processing unit 10, the transmission unit 12 and the switch array 13 are jointly disposed on the same circuit board 14, and the processing unit 10 is electrically connected to the transmission unit 12 and the contact switches 11 of the switch array 13 through the circuit board 14.

In one embodiment, the switch device 1 further includes one or more indicating units 15 (such as light-emitting elements or sound-emitting elements). The indicating unit 15 is used to indicate the state of the switch device 1 (e.g. when the switch device 1 is connected to the computer host 2 to light up or sound) or to indicate the state of the corresponding contact switch 11 (e.g. to light up or sound when the contact switch 11 is ready , Or extinguished or sounded when pressed).

Please refer to FIGS. 6 to 7B and 9 together. FIG. 6 is a schematic diagram of the appearance of a contact switch according to an embodiment of the present invention. FIG. 7A is a schematic cross-sectional view of the contact switch of FIG. 6 in a released state. 7B is a schematic cross-sectional view of the contact switch of FIG. 6 in a pressed state, and FIG. 9 is a schematic diagram of monitoring electrical signals of the contact switch according to an embodiment of the present invention.

In this embodiment, the aforementioned contact switches 11 may be mechanical digital switches, and are electrically connected to the circuit board 14, and the circuit board 14 is provided with a corresponding indicating unit 15 (herein, an LED).

In one embodiment, each contact switch 11 includes a key cap 30, a shaft structure 31, a switch housing 32, a first conductive sheet 34, a second conductive sheet 35 and a reset element 33. The switch housing 32 may include an upper housing 320 and a lower housing 321.

The first conductive sheet 34 and the second conductive sheet 35 are electrically connected to the processing unit 10. When the first conductive sheet 34 and the second conductive sheet 35 contact or separate (for example, the first conductive sheet 34 and the second conductive sheet 35 are connected to form Circuit, or when separated to form an open circuit), electrical signals of different potentials can be triggered. The axis structure 31 is used to move between the reset position and the trigger position to change the contact state between the first conductive sheet 34 and the second conductive sheet 35. The reset element 33 is used to provide a restoring force to move the shaft structure 31 toward the reset position. The key cap 30 is disposed above the shaft structure 31 for receiving external force to move the shaft structure 31 toward the trigger position.

In one embodiment, the first conductive sheet 34 and the second conductive sheet 35 are conductive metal sheets, and at least one of the first conductive sheet 34 and the second conductive sheet 35 has flexibility and can be used by the shaft. When the core structure 31 is pushed, it deforms and changes the contact state between the first conductive sheet 34 and the second conductive sheet 35, thereby triggering electrical signals of different potentials.

For example, as shown in FIG. 7A, when the user does not press the contact switch 11, the axial structure 31 is statically balanced by the upward restoring force of the reset element 33 and the downward positive force of the upper housing 320 at the same time. Reset position. In this state, the first conductive sheet 34 and the second conductive sheet 35 are not connected, so the electrical signal of the contact switch 11 presents a low potential (the potential before the time point S0 in FIG. 9).

As shown in FIG. 7B, the user can press the contact switch 11 to move the keycap 30 in conjunction with the shaft structure 31 downward to the trigger position. At this time, the first conductive sheet 34 is electrically connected to the second conductive sheet 35, so the electrical signal of the contact switch 11 changes to a high potential (the potential between the time points S0-S2 in FIG. 9). Moreover, at the moment when the first conductive sheet 34 and the second conductive sheet 35 are in contact, bounce noise (such as the noise between the time points S0-S1 in FIG. 9) will be generated.

Then, when the user releases the contact switch 11, the shaft structure 31 is simultaneously moved to the rest position by the upward restoring force of the restoring element 33. In this state, the first conductive sheet 34 and the second conductive The sheet 35 is disconnected, and at the moment when the first conductive sheet 34 and the second conductive sheet 35 are disconnected, bounce noise (such as the noise between the time points S2-S3 in FIG. 9) will be generated.

Please continue to refer to FIGS. 8A to 8B and FIG. 9. FIG. 8A is a schematic cross-sectional view of the contact switch of an embodiment of the present invention in the released state, and FIG. 8B is a schematic cross-sectional view of the contact switch of FIG. 8A in the pressed state .

In this embodiment, the aforementioned touch switches 11 may be thin-film digital switches. The first conductive sheet 40 and the second conductive sheet 41 are conductive films. A barrier film 42 is laid between the first conductive sheet 40 and the second conductive sheet 41. The barrier film 42 is used to block the first conductive sheet 40 (including the first contact 400 of the electrical connection processing unit 10) and the second conductive sheet 41 (including the second contact 410 of the electrical connection processing unit 10 ). The barrier film 42 is formed with positioning holes 43 vertically aligned with the first contact 400 and the second contact 410.

As shown in FIG. 8A, when no external force is applied to the keycap 30, the axis structure 31 is in the reset position, and the first contact 400 and the second contact 410 will not be connected. In this state, since the first conductive sheet 40 and the second conductive sheet 41 are not connected, the electrical signal of the contact switch 11 presents a low potential (the potential before the time point S0 in FIG. 9).

And, as shown in FIG. 8B, when an external force is applied to the keycap 30, the axial structure 31 squeezes the first conductive sheet 40, the first conductive sheet 40 is deformed and the first contact 400 passes through the positioning hole 43 to contact the first conductive sheet 40. The second contact 410 reaches the trigger position. At this time, the first contact 400 is connected to the second contact 410, and therefore the electrical signal of the contact switch 11 changes to a high potential (the potential between the time points S0-S2 in FIG. 9). In addition, at the moment when the first contact 400 and the second contact 410 are in contact, bounce noise (such as the noise between the time points S0-S1 in FIG. 9) will be generated.

Then, when the user releases the contact switch 11, the shaft structure 31 returns upward to the reset position at the same time. In this state, the first contact 400 is disconnected from the second contact 410, and at the moment when the first contact 400 is disconnected from the second contact 410, bounce noise will be generated (as shown in the time point S2 in FIG. 9). -Noise between S3).

Although in the foregoing embodiment, the contact switch 11 triggers a high-potential electrical signal when it is pressed, and a low-potential electrical signal when it is released, but it is not limited thereto.

In one embodiment, the contact switch 11 can also be modified to trigger a low-level electrical signal when it is pressed, and a high-level electrical signal when it is released.

Next, it will be described in detail how the present invention suppresses the aforementioned bounce suppression noise. The method for suppressing bounce noise in each embodiment of the present invention can be implemented by any switch device 1 shown in FIG. 1, FIG. 2, FIG. 6 to FIG. 8B.

Please also refer to FIG. 3, which is a flowchart of the method for suppressing bounce noise according to the first embodiment of the present invention. Specifically, the method for suppressing bounce noise of this embodiment includes the following steps.

Step S10: The processing unit 10 continuously monitors the electrical signal triggered by the contact switch 11, such as monitoring the electric potential of the electrical signal.

Step S11: The processing unit 10 judges whether the contact switch 11 is operated according to the received electric signal. For example, it is judged that the contact switch 11 is operated when the electric signal potential changes (time point S0 or S2 as shown in FIG. 9).

In one embodiment, the touch switch 11 reduces the electric signal potential from a high level to a low level when receiving a user's pressing operation (if it falls below the lower limit of the electric potential, the lower limit of the electric potential can be 0.3V); or When accepting the user's release operation, the electric signal's potential is raised from a low to a high level (if it rises above the upper limit of the potential) Value, the upper limit value of the potential can be 0.7V). In this way, the processing unit 10 can determine what kind of operation the contact switch 11 has received based on the change in the electric signal potential.

If the processing unit 10 determines that the contact switch 11 is operated, step S12 is executed. Otherwise, the processing unit 10 executes step S11 again.

Step S12: The processing unit 10 generates a corresponding switch signal according to the state of the operated contact switch 11 and the electrical signal, and immediately outputs the switch signal to the outside through the transmission unit 12.

For example, if the touch switch 11 is a key with the letter "K", when the processing unit 10 detects that the touch switch 11 is pressed, the output switch signal is used to instruct the computer host 2 to "start inputting K". When detecting that the contact switch 11 is released, the output switch signal is used to instruct the computer device 2 to “stop inputting K”.

Please refer to FIG. 9 and FIG. 10 at the same time. The present invention directly outputs the switch signal when the contact switch 11 is operated (that is, time point S0 or S2), and the existing technology for suppressing bounce noise is performed after the contact switch 11 is operated (Time point T0 or T3), the switch signal must be delayed to time point T2 or T5. Thereby, the present invention can indeed eliminate the delay of key triggering.

It is worth mentioning that at the same time, before or after the switch signal is sent, the processing unit 10 starts to count the preset critical time.

In one embodiment, the critical time can be any time value of 10 ms, no more than 15 milliseconds, or any time value no less than 10 milliseconds, and is not limited.

In one embodiment, the critical time must not be less than the noise time of the bouncing noise, and the aforementioned noise time can be obtained by experimental testing, experience accumulation, or statistics.

Step S13: The processing unit 10 stops determining whether the contact switch 11 is operated again within the critical time, that is, suspends monitoring the contact switch 11. For example, the processing unit 10 can directly ignore the potential change of the electrical signal during the critical time.

As shown in Fig. 9, the processing unit 10 starts counting the critical time (10ms in this example) at time point S0 or S2, and ignores the electrical signal within the critical time (ie, ignores time points S0-S1 or time points S2-S3). The electrical signal changes between).

It is worth mentioning that since the bounce noise is usually generated during this critical time, the present invention can effectively achieve the function of suppressing the bounce noise by directly ignoring the change of the electrical signal during this critical time.

Step S14: The processing unit 10 determines whether the critical time has passed. If the processing unit 10 determines that the critical time has passed, step S15 is executed. Otherwise, the processing unit 10 executes step S14 again.

Step S15: The processing unit 10 continues to determine whether the contact switch 11 is operated again according to the electrical signal after the timer critical time has elapsed, that is, resumes monitoring the contact switch 11.

Step S16: The processing unit 10 determines whether to terminate the noise suppression function, for example, the user removes the switch device 1 or manually turns off the noise suppression function.

If the processing unit 10 determines to terminate the noise suppression function, the execution of the method ends. Otherwise, the processing unit 10 executes step S11 again to continuously perform the noise suppression function.

It is worth mentioning that although in the foregoing example, a group of contact switches 11 and the critical time are taken as an example for description, it is not limited thereto.

In one embodiment, the method for suppressing bounce noise of the present invention can be used for multiple contact switches 11 (for example, for switch array 13). In addition, the aforementioned multiple contact switches 11 respectively correspond to multiple critical times, and the critical time corresponding to each contact switch 11 may be the same or different.

Please refer to FIG. 3 and FIG. 4 together. FIG. 4 is a flowchart of manually adjusting the critical time according to the second embodiment of the present invention. This embodiment further provides a function of manually adjusting the critical time, which allows the user to adjust the aforementioned critical time according to personal preferences to achieve the best operating experience.

For example, when the user feels that the current critical time is too short to suppress all the bounce noise (such as the phenomenon of the same key jumper), the critical time can be manually increased; when the user feels the current critical time is too long (If the same key cannot be operated continuously), the critical time can be reduced manually.

Compared with the method for suppressing bouncing noise shown in FIG. 3, the method for suppressing bouncing noise of this embodiment further includes the following steps for implementing the function of manually adjusting the critical time.

Step S20: The processing unit 10 switches to the manual adjustment mode according to the user operation. In one embodiment, the user operates the host computer 2 to make the host computer 2 enter the manual adjustment mode through the driver control switch device 1.

Step S21: The processing unit 10 receives the threshold time setting signal via the transmission unit 12. In one embodiment, the user inputs the desired time by operating the host computer 2, and the host computer 2 generates a threshold time setting signal according to the expected time input by the user and transmits it to the switch device 1.

Step S22: The processing unit 10 adjusts the critical time to the desired time input by the user according to the critical time setting signal, thereby completing the manual adjustment of the critical time.

Please refer to FIG. 3 and FIG. 5 together. FIG. 5 is a flowchart of automatically adjusting the critical time according to the third embodiment of the present invention. This embodiment further provides a function of automatically adjusting the critical time, which can automatically detect the state of the touch switch 11 and automatically set the optimal critical time to achieve the best continuous operation experience.

Step S30: The processing unit 10 is automatically switched to the automatic adjustment mode according to the user's operation or automatically. In the automatic adjustment mode, the processing unit 10 continuously monitors the electrical signal triggered by the contact switch 11.

In one embodiment, the user operates the computer host 2 to make the computer host 2 enter the automatic adjustment mode through the driver control switch device 1.

Step S31: The processing unit 10 determines whether the contact switch 11 is operated according to the received electrical signal.

If the processing unit 10 determines that the contact switch 11 is operated, step S32 is executed. Otherwise, the processing unit 10 executes step S31 again.

In one embodiment, the driver program can control the host computer 2 to prompt the user to operate the contact switches 11 in sequence on the display, so that the processing unit 10 obtains the electrical signals of the contact switches 11.

Step S32: The processing unit 10 analyzes and detects the electrical signals continuously triggered by the contact switch 11.

Step S33: The processing unit 10 identifies the bounce noise in the electrical signal, and calculates the noise time of the bounce noise, that is, the duration of the bounce noise.

Step S34: The processing unit 10 adjusts the critical time according to the noise time, where the adjusted critical time must not be less than the noise time to achieve the function of suppressing bounce noise, thereby completing the automatic adjustment of the critical time. .

In one embodiment, the processing unit 10 can calculate the corresponding multiple noise times according to the electrical signals triggered by the same contact switch 11 multiple times, and then adjust the critical time according to the multiple noise times, such as multiple The average or maximum value of the noise time is used as the critical time.

Of course, the present invention can also have various other embodiments. Without departing from the spirit and essence of the present invention, those with ordinary knowledge in the technical field to which the present invention belongs can make various corresponding changes and modifications according to the present invention, but these Corresponding changes and modifications should belong to the scope of the patent application attached to the present invention.

1: Switch device

10: Processing unit

11: Contact switch

12: Transmission unit

2: Computer host

Claims (9)

A switch device with a bounce noise suppression function includes: a contact switch that triggers an electrical signal when receiving an operation; includes a first conductive sheet electrically connected to the processing unit; and a second conductive sheet electrically connected to the processing unit The processing unit triggers the electrical signal when a contact state between the first conductive sheet and the second conductive sheet changes; an axis structure is used to move between a reset position and a trigger position to change the first conductive The contact state between the sheet and the second conductive sheet; a reset element for providing a restoring force to move the shaft structure toward the reset position; and a keycap disposed above the shaft structure for Receiving external force to move the shaft structure toward the trigger position; a transmission unit for connecting to a computer host; and a processing unit electrically connected to the contact switch and the transmission unit, and the processing unit determines according to the electrical signal When the contact switch is operated, it immediately outputs a switch signal corresponding to the electrical signal through the transmission unit, counts a critical time and stops judging whether the contact switch is operated again during the critical time, and at the critical time After passing, continue to judge whether the contact switch is operated again according to the electrical signal. The switch device with bounce noise suppression function according to claim 1, wherein the contact switch reduces the potential of the electrical signal from a high to lower than a lower limit of potential when receiving a pressing operation, or when receiving a pressing operation During a release operation, the potential of the electrical signal is raised above a potential upper limit value. The switch device with bounce noise suppression function according to claim 1, wherein the critical time is not less than 10 milliseconds and not more than 15 milliseconds. The switch device with bounce noise suppression function according to claim 1, wherein the processing unit receives a threshold time setting signal through the transmission unit in a manual adjustment mode, and adjusts the threshold time according to the threshold time setting signal. The switch device with bounce noise suppression function according to claim 1, wherein when the contact switch is operated in an automatic adjustment mode, the processing unit detects the electrical signal continuously triggered by the contact switch, and recognizes the A bounce noise in the electrical signal is calculated, a noise time of the bounce noise is calculated, and the critical time is adjusted according to the noise time, and the adjusted critical time is not less than the noise time. The switch device with bounce noise suppression function according to claim 1, wherein the contact switch is a mechanical digital switch, the first conductive sheet and the second conductive sheet are conductive metal sheets, and the first conductive sheet At least one of the second conductive sheets has flexibility. The switch device with bounce noise suppression function according to claim 1, wherein the contact switch is a thin-film digital switch, and the first conductive sheet and the second conductive sheet are conductive films. The switch device with bounce noise suppression function according to claim 1, which further includes a circuit board and a switch array, the switch array includes the plurality of contact switches, and the processing unit is electrically connected to the circuit board via the circuit board. The switch array and the transmission unit. The switch device with bounce noise suppression function according to claim 8, wherein the plurality of contact switches respectively correspond to the plurality of different critical times.

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