Key input circuit far away from processor, key input assembly and electronic equipment
By designing a button input circuit far away from the processor in electronic devices, and using the button resistor to form a differentiated acquisition voltage, the problem of complex connection between the button input components and the processor in the prior art is solved, and the effect of simplifying connections, reducing costs and miniaturizing and lightweighting is achieved.
Patent Information
- Application Number
- CN202420732085.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-10
- Publication Date
- 2025-05-02
- Estimated Expiration
- 2034-04-10
AI Technical Summary
In existing electronic devices, the distance between the key input component and the processor is large, resulting in an increase in connection lines, high resource usage, and corresponding increase in costs.
A key input circuit away from the processor is designed, and a key branch is formed by connecting each key with different resistance values in series. These branches are connected in parallel and then connected to the working power supply through series resistors. To generate differentiated acquisition voltage, it only needs to input it to the processor through two cables.
Reduces the number of connection lines between the key input component and the processor, reduces resource usage and cost, while helping to miniaturize and lightweight electronic devices.
Smart Images
Figure CN222827219U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of key input, in particular to a key input circuit and a key input component and an electronic device far away from a processor. Background Art
[0002] In actual applications, there is a large distance between the key input components in some electronic devices and the main controller of the electronic device. For example, the overall volume of a handheld cleaner is relatively large, the main controller is usually located around the cleaning component, and the key input component is located on the handle. In this way, the distance between multiple buttons on the handle and the main controller is relatively large, and some are as long as 50 cm or even larger.
[0003] In existing key input components, the electrical signals from each key are usually input to the main controller in the form of an input-output (I / O) bus connection. For example, n key signals are connected to the I / O pins of the main controller through n cables. Although this single-key single I / O bus connection method for multiple keys is simple, it increases the connection lines, connection sockets, and main controller resource usage, and also increases costs. Summary of the invention
[0004] The utility model provides a key input circuit, a key input component and an electronic device which are far away from a processor, so as to simplify the connection mode between the key input component and the processor.
[0005] The utility model provides a key input circuit far away from a processor in a first aspect, wherein the key input circuit comprises N keys, wherein N is a natural number greater than 1,
[0006] Each key has a key resistor of different resistance value connected in series to form a key branch of each key.
[0007] After each key branch is connected in parallel, it is connected to the two ends of the working power supply for providing working voltage for the key input circuit through a series resistor.
[0008] The divided voltage generated by the working power supply in the series resistor or the key branch is used as the acquisition voltage and input to the analog-to-digital conversion pin and the ground pin of the processor through two cables.
[0009] in,
[0010] When different keys are operated or different combination keys are operated, the collected voltage has different magnitudes.
[0011] Preferably, after the key branches are connected in parallel, they are connected to two ends of a working power supply for providing a working voltage for the key input circuit through a series resistor, including:
[0012] After one end of the series resistor is connected in series with one end of the parallel key branch, the other end of the series resistor is electrically connected to the positive electrode of the working power supply, and the other end of the parallel key branch is electrically connected to the negative electrode of the working power supply;
[0013] or,
[0014] After one end of the series resistor is connected in series with one end of the parallel key branch, the other end of the series resistor is electrically connected to the negative pole of the working power supply, and the other end of the parallel key branch is electrically connected to the positive pole of the working power supply.
[0015] Preferably, the divided voltage generated by the working power supply in the series resistor or the key branch is used as a collection voltage and input to the analog-to-digital conversion pin and the ground pin of the processor through two cables, including:
[0016] The high potential end of the two ends of the parallel key branch is electrically connected to the analog-to-digital conversion pin of the processor, and the low potential end is electrically connected to the ground pin of the processor.
[0017] or,
[0018] Of the two ends of the series resistor, the high potential end is electrically connected to the analog-to-digital conversion pin of the processor, and the low potential end is electrically connected to the ground pin of the processor.
[0019] Preferably, two ends of the series resistor or the key branch are also connected in parallel with a capacitor;
[0020] The cable length is greater than a set length threshold;
[0021] The resistance value of the button resistor is configured as follows:
[0022] The equivalent key resistance value of any combination key in the combination key mode is different from the key resistance value of each key in the single key mode, and the equivalent key resistance values of each combination key are different from each other.
[0023] and,
[0024] The minimum voltage difference between the first acquisition voltage output in the first key mode and the second acquisition voltage output in the second key mode is greater than or equal to m times the product of the processor analog-to-digital conversion accuracy and the range voltage configured for the analog-to-digital conversion;
[0025] in,
[0026] There is at least one different key between the operated key corresponding to the first key mode and the operated key corresponding to the second key mode.
[0027] The value of m is selected so that the minimum voltage difference is greater than the ripple peak value of the analog-to-digital conversion range voltage.
[0028] Preferably, the first key mode is a combination mode in which two keys are operated simultaneously, or a single key mode in which a single key is operated, and / or the second key mode is a combination mode in which two keys are operated simultaneously, or a single key mode in which a single key is operated;
[0029] The acquisition voltage output by the key circuit enables the processor to detect whether the key is operated for a long time or a short time according to the duration of the acquisition voltage, and / or detect the working state of the key according to the magnitude of the acquisition voltage.
[0030] Preferably, the acquisition voltage output by the key circuit enables the processor to detect whether the key is operated for a long time or a short time according to the duration of the acquisition voltage being maintained, including:
[0031] The sampling voltage output by the key circuit enables: the processor to sample the input sampling voltage according to the set sampling period within the set time length, and compare the sampling voltage sampled each time with the first sampling voltage obtained by the processor within the time length. If the sampling voltage sampled at any time is not equal to the first sampling voltage, it is determined that the current key is operated for a short time, otherwise, it is determined that the current key is operated for a long time.
[0032] Preferably, the processor is located in the body of the handheld cleaner near the cleaning assembly, and the key input circuit is located in the handle of the handheld cleaner;
[0033] The detecting the working state of the button according to the collected voltage includes:
[0034] The collected voltage output by the key circuit enables: the processor to compare the collected voltage with the pre-configured key value voltage, and when the two are equal, it is determined that the key corresponding to the key value voltage is operated.
[0035] A second aspect of the utility model provides a key input component far away from a processor, and the key input component comprises any one of the key input circuits far away from the processor.
[0036] A third aspect of the utility model provides an electronic device, which includes any one of the key input circuits located away from the processor.
[0037] Preferably, the electronic device is a handheld cleaner, the key input circuit is located at the handle of the handheld cleaner, and the processor is located in a body of the handheld cleaner near a cleaning component.
[0038] The utility model provides a key input circuit far away from a processor, which uses the divided voltage generated by a working power supply in a key branch with a series resistor or key resistors with different resistance values as a collection voltage and inputs it to the processor, so that only two cables are needed to connect the key input circuit to the processor. Compared with the connection method of the I / O bus, the number of cables, connection sockets, and processor resources are reduced, which is conducive to miniaturization and lightweight for electronic devices with a long distance between the key input circuit and the processor. BRIEF DESCRIPTION OF THE DRAWINGS
[0039] Figure 1 A schematic diagram of a key input circuit far away from the processor according to an embodiment of the present application.
[0040] Figure 2 A schematic diagram of a key input circuit according to an embodiment of the present application.
[0041] Figure 3 A schematic diagram of a processor detecting whether a key is operated for a long time or a short time according to the duration of the collected voltage.
[0042] Figure 4 This is a schematic diagram of the key input circuit of the second embodiment of the present application.
[0043] Figure 5 This is a schematic diagram of the key input circuit of Example 3 of the present application.
[0044] Figure 6 This is a schematic diagram of the key input circuit of the fourth embodiment of the present application. DETAILED DESCRIPTION
[0045] In order to make the objectives, technical means and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings.
[0046] The applicant found that the single-key single I / O bus connection method for multiple keys results in that the key input components far away from the processor require multiple cables to connect to the processor, which increases the space occupied by the cables, which is not conducive to the miniaturization and lightweight of the electronic device.
[0047] In view of this, the utility model provides a key input circuit far away from the processor, which characterizes the key value of the key by outputting differentiated key voltage sizes to the processor, so that the number of connecting cables between the key input component and the processor is only 2, which greatly reduces the space occupied by the cables and simplifies the connection method between the key input component and the processor.
[0048] See also Figure 1 As shown, Figure 1A schematic diagram of a key input circuit far from the processor in an embodiment of the present application. The key input circuit includes: N keys, where N is a natural number greater than 1,
[0049] Each key has a key resistor of different resistance value connected in series to form a key branch of each key.
[0050] After each key branch is connected in parallel, it is connected to the two ends of the working power supply for providing working voltage for the key input circuit through a series resistor.
[0051] The divided voltage generated by the working power supply in the series resistor or the key branch is used as the acquisition voltage and input to the analog-to-digital conversion (ADC) pin and the ground pin of the processor through two cables, for example Figure 1 In the example, cable 1 is input to the ADC pin of the processor, and cable 2 is input to the ground pin of the processor.
[0052] in,
[0053] When different keys are operated or different combination keys are operated, the acquisition voltages are different in magnitude, so that the key values of different keys and their different combination keys can be represented by different acquisition voltages.
[0054] It should be understood that, in this embodiment, the combination key refers to the situation where different keys are operated at the same time, and being far away from the processor refers to the situation where the length of the cable connected between the key input circuit and the processor is greater than the set length threshold, and the key resistor can be one or multiple resistors connected in series, parallel, or mixed. The series resistor can be one or multiple resistors connected in series, parallel, or mixed.
[0055] As an example, the acquisition voltage output by the key circuit enables the processor to detect whether the key is operated for a long time or a short time based on the length of time the acquisition voltage is maintained. This detection can be achieved through the analog-to-digital conversion module, comparison module and timing module built into the processor, and / or the working status of the key can be detected based on the size of the acquisition voltage. These detections can be achieved through the analog-to-digital conversion module and comparison module built into the processor.
[0056] As an example, after one end of the series resistor is connected in series with one end of the parallel-connected key branch, the other end of the series resistor is electrically connected to the positive electrode of the working power supply, and the other end of the parallel-connected key branch is electrically connected to the negative electrode of the working power supply;
[0057] or,
[0058] After one end of the series resistor is connected in series with one end of the parallel key branch, the other end of the series resistor is electrically connected to the negative electrode of the working power supply, and the other end of the parallel key branch is electrically connected to the positive electrode of the working power supply;
[0059] The high potential end of the two ends of the parallel key branch is electrically connected to the analog-to-digital conversion pin of the processor, and the low potential end is electrically connected to the ground pin of the processor.
[0060] or,
[0061] Of the two ends of the series resistor, the high potential end is electrically connected to the analog-to-digital conversion pin of the processor, and the low potential end is electrically connected to the ground pin of the processor;
[0062] In the above example, connecting the negative pole of the working power supply to the ground pin of the processor is beneficial to the stability of the system.
[0063] As an example, a capacitor is also connected in parallel at both ends of the series resistor or the key branch to suppress noise in the collected voltage. It should be understood that when a capacitor is connected in parallel at both ends of the key branch, a capacitor can be connected in parallel at both ends of the parallel-connected key branch, or a capacitor can be connected in parallel at both ends of each key branch. The former is more conducive to the simplification of the key input circuit than the latter. The capacitor can be one or multiple capacitors connected in series, parallel, or mixed.
[0064] In order to characterize the key values of different keys and their different key combinations through different acquisition voltages, the resistance value of the key resistor is determined as follows:
[0065] The equivalent key resistance value of any combination key in the combination key mode is different from the key resistance value of each key in the single key mode, and the equivalent key resistance values of each combination key are different from each other;
[0066] and,
[0067] The minimum voltage difference between the first acquisition voltage output in the first key mode and the second acquisition voltage output in the second key mode is greater than or equal to m times the product of the processor analog-to-digital conversion accuracy and the range voltage configured for the analog-to-digital conversion;
[0068] in,
[0069] There is at least one different key between the operated key corresponding to the first key mode and the operated key corresponding to the second key mode.
[0070] The value of m is selected so that the minimum voltage difference is greater than the ripple peak value of the analog-to-digital conversion range voltage.
[0071] For example, taking into account relevant errors, including but not limited to:
[0072] 1) The precision error of the resistance of electronic devices is about 5%;
[0073] 2) The ripple error of the ADC range voltage. For example, if the ADC range voltage is 1.8V or 3.3V, the ripple peak is about 30mV.
[0074] 3) ADC quantization noise error. For example, if the ADC quantization bit number is 12 bits, the conversion accuracy is: 1 / 2^12=1 / 4096.
[0075] According to the minimum voltage difference, which must be greater than the peak voltage ripple of the ADC range, the engineering experience reference value m=10 can be used. That is to say, the voltage difference between different buttons, including the voltage difference between combination buttons, can have a minimum value of 300mV.
[0076] In the embodiment of the present application, the divided voltage generated by the series resistor or the key branch with different resistance values through the working power supply is used as the collection voltage, so that different collection voltage sizes can represent different key values or key values of different combination keys. In this way, the collection voltage only needs to be input to the processor through two cables, thereby greatly reducing the number of cables and simplifying the connection method between the key input circuit and the processor.
[0077] To facilitate understanding of the embodiments of the present application, a handheld cleaner is used as an example for explanation below. It should be understood that the embodiments of the present application are not limited to handheld cleaners, but can be applied to other miniaturized and lightweight electronic devices.
[0078] See also Figure 2 As shown, Figure 2 This is a schematic diagram of a key input circuit of an embodiment of the present application. Each key is connected in series with one or more key resistors, represented by a resistor in the figure. Each key and the key resistor connected in series form a key branch. In this way, n keys have n key branches. Different key branches are connected in parallel and connected in series with a resistor to divide the working power supply. For the convenience of writing, the resistor connected in series with the key branches after parallel connection is called a series resistor.
[0079] like Figure 2 As shown, one end of the series resistor is electrically connected to the positive electrode of the working power supply, and the other end is electrically connected to one end of the parallel key branch, and the other end of the parallel key branch is electrically connected to the negative electrode of the working power supply. Capacitors are connected to both ends of the parallel key branch to suppress noise in the output divided voltage, and the divided voltage is input to the processor as a collection voltage, wherein the high potential end of the parallel key branch, i.e., the connection point between the series resistor and the parallel key branch, is electrically connected to the analog-to-digital conversion pin of the processor through a line, and the low potential end of the parallel key branch, i.e., the negative electrode of the working power supply, is connected to the ground pin of the processor.
[0080] When no button is pressed, the collected voltage is the working power supply voltage V CC, for example 3.3V, since the resistance values of the resistors of each button are different, the voltage-dividing resistors formed when different buttons are pressed are different, and the voltage-dividing resistors formed when multiple buttons are pressed in combination have different resistance values.
[0081] Take the five independent buttons in the figure as an example.
[0082] The collected voltage generated when any key x is pressed is:
[0083]
[0084] Among them, V x is the collected voltage generated when key x is pressed, R x is the key resistance of key x, R1 is the series resistance, V CC is the working power supply voltage.
[0085] Specifically, for example:
[0086] When the SW1 button is pressed alone, the collected voltage is V1
[0087] When the SW2 button is pressed alone, the collected voltage is V2
[0088] When the SW3 button is pressed alone, the collected voltage is V3
[0089] When the SW4 button is pressed alone, the collected voltage is V4
[0090] When the SW5 button is pressed alone, the collected voltage is V5
[0091] Similarly, when any two buttons x and y are pressed in combination, the generated collected voltage is:
[0092]
[0093] Among them, V xy is the collected voltage generated when keys x and y are pressed, R xy is the parallel resistance of the key resistance of key x and the key resistance of key y, R1 is the series resistance, V CC is the working power supply voltage.
[0094] Specifically, for example:
[0095] Press SW1 and SW2 buttons in combination to collect voltage V 12
[0096] Press SW1 and SW3 buttons in combination to collect voltage V 13
[0097] Press SW1 and SW4 buttons in combination to collect voltage V 14
[0098] Press SW1 and SW5 keys together to collect voltage V 15
[0099] Press SW2 and SW3 buttons in combination to collect voltage V 23
[0100] Press SW2 and SW4 buttons in combination to collect voltage V 24
[0101] Press SW2 and SW5 buttons in combination to collect voltage V 25
[0102] Press SW3 and SW4 buttons in combination to collect voltage V 34
[0103] Press SW3 and SW5 buttons in combination to collect voltage V 35
[0104] Press SW4 and SW5 buttons in combination to collect voltage V 45
[0105] Among the 15 different key modes mentioned above, there is at least one different key between any two key modes.
[0106] In order to distinguish the collected voltages under different key modes, the minimum voltage difference between any two collected voltages under the above 15 different key modes satisfies:
[0107] ΔV ≥ mαγ
[0108] Among them, ΔV is the minimum voltage difference, m is the set multiple, α is the analog-to-digital conversion accuracy, and γ is the configured analog-to-digital conversion range voltage.
[0109] For example, if the ADC quantization bit is 10 bits and the ADC configuration range voltage is 3.3V, then
[0110]
[0111] In this way, the resistance value of each button resistor can be configured so that the minimum voltage difference between any two collected voltages is greater than or equal to 32 mV.
[0112] It should be understood that the above-mentioned combination of keystrokes is not limited to a combination of two keys, but may also be a combination of more than two keys, such as three, four, etc.
[0113] When the collected voltage is input to the processor, the processor compares the input collected voltage with the pre-configured key value voltage. If the two are the same, it is determined that the key corresponding to the key value voltage is pressed. The key value voltage is configured according to formulas 1 and 2.
[0114] In addition, the processor can also detect whether the key is operated for a long time or a short time, for example, long press or short press, according to the duration of the collected voltage.
[0115] As an example, see Figure 3 As shown, Figure 3 A schematic diagram of a processor detecting whether a key is pressed for a long time or a short time according to the duration of the collected voltage. Once the processor detects that a key is pressed, it starts to detect whether it is a long key press. For example, if the key is kept pressed for a set duration, it is considered a long press.
[0116] Once the processor detects that the key is pressed, it starts the built-in timer for timing the sampling period in the processor, and samples the input acquisition voltage at the set sampling period within the set time. For example, if the set time s is 2s and the sampling period T is 20ms, the total number of acquisitions is:
[0117] s / T=2s / 20ms=100
[0118] The sampled voltage sampled each time is compared with the first sampled voltage obtained when the key is pressed. If any sampled voltage is not equal to the first sampled voltage, it is judged as a short press. If the sampled voltages sampled within the set time are all equal to the first sampled voltage, it is judged as a long press.
[0119] See also Figure 4 As shown, Figure 4 A schematic diagram of the key circuit of the second embodiment of the present application. In this embodiment, one end of the key branch after parallel connection is electrically connected to the positive electrode of the working power supply, and the other end is electrically connected to one end of the series resistor, and the other end of the series resistor is electrically connected to the negative electrode of the working power supply, that is, the ground terminal, and the two ends of the key branch after parallel connection are electrically connected to the processor through a cable, wherein the high potential end of the key branch after parallel connection, that is, the positive electrode of the working power supply, is electrically connected to the ADC pin of the processor, and the low potential end of the key branch after parallel connection, that is, the connection point between the key branch after parallel connection and the series resistor, is electrically connected to the ground pin of the processor, and when no key is pressed, the collected voltage is the working power supply voltage. Capacitors are also connected in parallel at both ends of the key branch after parallel connection.
[0120] See also Figure 5 As shown, Figure 5This is a schematic diagram of the key circuit of the third embodiment of the application. In this embodiment, one end of the series resistor is electrically connected to the positive electrode of the working power supply, and the other end is electrically connected to one end of the key branch after parallel connection, and the other end of the key branch after parallel connection is electrically connected to the negative electrode of the working power supply. The two ends of the series resistor are electrically connected to the processor through a cable, wherein the high potential end of the series resistor, i.e., the high potential end of the working power supply, is electrically connected to the analog-to-digital conversion pin of the processor through a cable, and the low potential end of the series circuit, i.e., the connection between the series circuit and the key branch, is connected to the ground pin of the processor. When no key is pressed, the collected voltage is 0. A capacitor is also connected in parallel to both ends of the series resistor.
[0121] See also Figure 6 As shown, Figure 6 A schematic diagram of the key circuit of the fourth embodiment of the application. In this embodiment, one end of the parallel key branch is electrically connected to the positive electrode of the working power supply, and the other end is electrically connected to one end of the series resistor, and the other end of the series resistor is electrically connected to the negative electrode of the working power supply, that is, the ground terminal, and the two ends of the series resistor are electrically connected to the processor through a cable, wherein the high potential end of the series resistor, that is, the connection between the parallel key branch and the series resistor, is electrically connected to the ADC pin of the processor, and the low potential end of the series resistor, that is, the negative electrode of the working power supply, is electrically connected to the ground pin of the processor, and when no key is pressed, the collected voltage is 0. Capacitors are also connected in parallel at both ends of the series resistor.
[0122] exist Figure 5 and 6 In the example, the voltage collected when any key x is pressed is:
[0123]
[0124] Among them, V x is the collected voltage generated when key x is pressed, R x is the key resistance of key x, R1 is the series resistance, V CC is the working power supply voltage.
[0125] As an example, the key circuit is located at the handle of the handheld cleaner body, and the processor is located at a position of the handheld cleaner body close to the cleaning component.
[0126] In the embodiments of the present application, the processor may be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it may also be a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components.
[0127] As for the apparatus / network-side device / storage medium embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.
[0128] In this article, relational terms such as first and second, etc. are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.
[0129] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.
Claims
1. A key input circuit far away from a processor, characterized in that: The key input circuit includes N keys, where N is a natural number greater than 1. Each key has a key resistor of different resistance value connected in series to form a key branch of each key. After each key branch is connected in parallel, it is connected to the two ends of the working power supply for providing working voltage for the key input circuit through a series resistor. The divided voltage generated by the working power supply in the series resistor or the key branch is used as the acquisition voltage and input to the analog-to-digital conversion pin and the ground pin of the processor through two cables. in, When different keys are operated or different combination keys are operated, the collected voltage has different magnitudes.
2. The key input circuit according to claim 1, characterized in that: After the key branches are connected in parallel, they are connected to two ends of a working power supply for providing a working voltage for a key input circuit through a series resistor, including: After one end of the series resistor is connected in series with one end of the parallel key branch, the other end of the series resistor is electrically connected to the positive electrode of the working power supply, and the other end of the parallel key branch is electrically connected to the negative electrode of the working power supply; or, After one end of the series resistor is connected in series with one end of the parallel key branch, the other end of the series resistor is electrically connected to the negative pole of the working power supply, and the other end of the parallel key branch is electrically connected to the positive pole of the working power supply.
3. The key input circuit according to claim 1, characterized in that: The divided voltage generated by the working power supply in the series resistor or the key branch is input as a collection voltage to the analog-to-digital conversion pin and the ground pin of the processor through two cables, including: The high potential end of the two ends of the parallel key branch is electrically connected to the analog-to-digital conversion pin of the processor, and the low potential end is electrically connected to the ground pin of the processor. or, Of the two ends of the series resistor, the high potential end is electrically connected to the analog-to-digital conversion pin of the processor, and the low potential end is electrically connected to the ground pin of the processor.
4. The key input circuit according to any one of claims 1 to 3, characterized in that: The two ends of the series resistor or the key branch are also connected in parallel with a capacitor; The cable length is greater than a set length threshold; The resistance value of the button resistor is configured as follows: The equivalent key resistance value of any combination key in the combination key mode is different from the key resistance value of each key in the single key mode, and the equivalent key resistance values of each combination key are different from each other. and, The minimum voltage difference between the first acquisition voltage output in the first key mode and the second acquisition voltage output in the second key mode is greater than or equal to m times the product of the processor analog-to-digital conversion accuracy and the range voltage configured for the analog-to-digital conversion; in, There is at least one different key between the operated key corresponding to the first key mode and the operated key corresponding to the second key mode. The value of m is selected so that the minimum voltage difference is greater than the ripple peak value of the analog-to-digital conversion range voltage.
5. The key input circuit according to claim 4, characterized in that: The first key mode is a combination mode in which two keys are operated simultaneously, or a single key mode in which a single key is operated, and / or the second key mode is a combination mode in which two keys are operated simultaneously, or a single key mode in which a single key is operated; The acquisition voltage output by the key circuit enables the processor to detect whether the key is operated for a long time or a short time according to the duration of the acquisition voltage, and / or detect the working state of the key according to the magnitude of the acquisition voltage.
6. The key input circuit according to claim 5, characterized in that: The acquisition voltage output by the key circuit enables the processor to detect whether the key is operated for a long time or a short time according to the duration of the acquisition voltage being maintained, including: The sampling voltage output by the key circuit enables: the processor to sample the input sampling voltage according to the set sampling period within the set time length, and compare the sampling voltage sampled each time with the first sampling voltage obtained by the processor within the time length. If the sampling voltage sampled at any time is not equal to the first sampling voltage, it is determined that the current key is operated for a short time, otherwise, it is determined that the current key is operated for a long time.
7. The key input circuit according to claim 5, characterized in that: The processor is located in the body of the handheld cleaner near the cleaning assembly, and the key input circuit is located in the handle of the handheld cleaner; The detecting the working state of the button according to the collected voltage includes: The collected voltage output by the key circuit enables: the processor to compare the collected voltage with the pre-configured key value voltage, and when the two are equal, it is determined that the key corresponding to the key value voltage is operated.
8. A key input component remote from a processor, characterized in that: The key input component comprises a key input circuit remote from a processor as claimed in any one of claims 1 to 7.
9. An electronic device, characterized in that: The electronic device comprises a key input circuit remote from a processor as claimed in any one of claims 1 to 7.
10. The electronic device according to claim 9, characterized in that: The electronic device is a handheld cleaner, the key input circuit is located at the handle of the handheld cleaner, and the processor is located in the body of the handheld cleaner near the cleaning component.