Wireless capacitive pen

Abstract

The utility model aims to provide a wireless capacitive pen, which is applied to IOS equipment and comprises a low-power-consumption Bluetooth chip, a key, an LED lamp group, a flexible printed circuit (FPC) connector and a rolling switch, and the key, the LED lamp group, the FPC connector and the rolling switch are respectively connected with the Bluetooth chip. When the wireless capacitive pen is in a power-on state, the Bluetooth chip and the LED lamp set are turned on, the rolling switch is in a high-level state, and PWM waves are output through the FPC connector; the key establishes the touch connection with the IOS equipment through the touch operation on the IOS equipment, and the Bluetooth chip with low power consumption is adopted as the master control, so that the power consumption is low, and the key can also adapt to various IOS equipment with higher configuration.

Description

Technical Field

[0001] The utility model relates to the technical field of touch pens, in particular to a wireless capacitive pen. Background Art

[0002] In the prior art, a capacitive pen is a pen made of conductive material with conductive properties, used to touch a capacitive screen to complete human-computer interaction operations; a capacitive pen is an auxiliary device that uses conductive material to imitate the human body (such as fingers, etc.) to complete human-computer interaction. It is composed of multiple technologies such as radio electronics, radio frequency technology, and scanning positioning technology. It uses a built-in capacitive sensor to sense the position and shape of contact with the screen, thereby realizing functions such as handwriting input and drawing. However, the capacitive pens currently on the market have relatively single functions, only realizing touch operation, lacking expansion functions, fast power consumption resulting in frequent charging, slow charging speed, and the outdated design of the charging port using Micro-B. Utility Model Content

[0003] One purpose of the utility model is to provide a wireless capacitive pen, which adopts a low-power Bluetooth chip as a main control, has low power consumption, and can also be adapted to various IOS devices with higher configurations.

[0004] According to one aspect of the utility model, a wireless capacitive pen is provided, which is applied to an IOS device and is characterized in that:

[0005] The wireless capacitive pen comprises a low-power Bluetooth chip and a key, an LED light group, a flexible circuit board (FPC) connector and a rolling switch respectively connected to the Bluetooth chip;

[0006] When the wireless capacitive pen is in the power-on state, the Bluetooth chip and the LED light group are turned on, the scroll switch is in a high level state, and a PWM wave is output through the FPC connector;

[0007] The button establishes a touch connection with the IOS device through a touch operation on the IOS device.

[0008] Furthermore, in the wireless capacitive pen, the wireless capacitive pen further comprises: a charging management IC connected to the Bluetooth chip, the charging management IC being connected to the lithium battery in the wireless capacitive pen;

[0009] The charging management IC is also connected to the Type-C interface on the wireless capacitive pen.

[0010] Furthermore, in the above wireless capacitive pen, the wireless capacitive pen further comprises: a protection circuit connected to the lithium battery in the wireless capacitive pen to protect the lithium battery in a charging state or in a use state.

[0011] Furthermore, in the above wireless capacitive pen, the wireless capacitive pen also includes: a voltage management unit connected to the Bluetooth chip and the lithium battery in the wireless capacitive pen respectively, so as to step down the output voltage of the lithium battery and output it to the Bluetooth chip in a stable voltage.

[0012] Furthermore, in the above wireless capacitive pen, the wireless capacitive pen further comprises: a voltage detection circuit connected to the Bluetooth chip and the lithium battery in the wireless capacitive pen respectively, so as to output the detected voltage of the lithium battery to the Bluetooth chip.

[0013] Furthermore, in the above wireless capacitive pen, the wireless capacitive pen also includes: a power supply interface connected to the Bluetooth chip and the lithium battery in the wireless capacitive pen respectively, and the Bluetooth chip is powered by the lithium battery.

[0014] Furthermore, in the above-mentioned wireless capacitive pen, the wireless capacitive pen also includes: a power detection circuit connected to the lithium battery in the wireless capacitive pen, the power detection circuit is connected to the Bluetooth chip through ADC, and the power percentage of the lithium battery is transparently transmitted to the IOS device through the Bluetooth chip.

[0015] Furthermore, in the above wireless capacitive pen, the wireless capacitive pen also includes: a 32M crystal oscillator connected to the Bluetooth chip, and the internal clock of the Bluetooth chip is calibrated by the 32M crystal oscillator.

[0016] Furthermore, in the above wireless capacitive pen, the wireless capacitive pen further comprises: a debugging interface connected to the Bluetooth chip, and the Bluetooth chip downloads and debugs the program in the Bluetooth chip through the debugging interface.

[0017] Furthermore, in the above-mentioned wireless capacitive pen, the LED light group includes four LED lights, and when the wireless capacitive pen is in a charging state or a power-on state, different numbers of LED lights are lit according to the power level of the lithium battery in the wireless capacitive pen.

[0018] Compared with the prior art, the utility model provides a wireless capacitive pen, which is applied to IOS devices, wherein the wireless capacitive pen comprises a low-power Bluetooth chip and a button, an LED light group, a flexible circuit board (FPC) connector and a scroll switch respectively connected to the Bluetooth chip; when the wireless capacitive pen is in a powered-on state, the Bluetooth chip and the LED light group are turned on, the scroll switch is in a high-level state, and a PWM wave is output through the FPC connector; the button establishes a touch connection with the IOS device through a touch operation on the IOS device, and by adopting a low-power Bluetooth chip as the main control, the power consumption is low and it can also be adapted to various IOS devices with higher configurations.

[0019] Furthermore, the wireless capacitive pen also includes: a charging management IC connected to the Bluetooth chip, and the charging management IC is connected to the lithium battery in the wireless capacitive pen; the charging management IC is also connected to the Type-C interface on the wireless capacitive pen, so that the wireless capacitive pen can be quickly charged through the Type-C interface, and the charging current can reach up to 800mA.

[0020] Furthermore, the wireless capacitive pen also includes: a voltage detection circuit connected to the Bluetooth chip and the lithium battery in the wireless capacitive pen respectively, so as to output the detected voltage of the lithium battery to the Bluetooth chip, so that the Bluetooth chip detects whether the lithium battery has started charging or needs to be automatically shut down according to the voltage of the lithium battery, thereby allowing the Bluetooth chip to know that the lithium battery has started charging or to shut down the wireless capacitive pen.

[0021] Furthermore, the wireless capacitive pen also includes: a power detection circuit connected to the lithium battery in the wireless capacitive pen, the power detection circuit is connected to the Bluetooth chip via ADC, and the power percentage of the lithium battery is transparently transmitted to the IOS device via the Bluetooth chip, so that the power percentage and charging status icon of the lithium battery of the wireless capacitive pen are displayed on the desktop widget of the IOS device. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Other features, objects and advantages of the present invention will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings:

[0023] Figure 1 A schematic structural diagram of a wireless capacitive stylus according to one aspect of the utility model is shown;

[0024] Figure 2 A schematic diagram showing the connection of components of an FPC connector in a wireless capacitive pen according to one aspect of the utility model;

[0025] Figure 3 A schematic diagram showing the connection of components in a charging management IC in a wireless capacitive pen according to one aspect of the utility model;

[0026] Figure 4 A schematic diagram showing the connection of components of a Type-C interface in a wireless capacitive pen according to one aspect of the utility model is shown;

[0027] Figure 5 A schematic diagram showing the connection of components of a protection circuit in a wireless capacitive pen according to one aspect of the utility model;

[0028] Figure 6A schematic diagram showing the connection of components of a voltage management unit in a wireless capacitive pen according to one aspect of the utility model;

[0029] Figure 7 A schematic diagram showing the connection of components of a voltage detection circuit in a wireless capacitance pen according to one aspect of the utility model;

[0030] Figure 8 A schematic diagram showing the connection of components of a power supply interface in a wireless capacitive pen according to one aspect of the utility model;

[0031] Fig. 9 A schematic diagram showing the connection of components of a power detection circuit in a wireless capacitive pen according to one aspect of the utility model;

[0032] Fig.10 A schematic diagram showing the connection between a Bluetooth chip and various components in a wireless capacitive pen according to one aspect of the utility model;

[0033] Fig.11 A schematic diagram showing the connection of components in each LED lamp in a wireless capacitive pen according to one aspect of the utility model;

[0034] Fig.12 A schematic diagram of a system flow of a wireless capacitive pen in an actual application scenario according to one aspect of the utility model is shown.

[0035] The same or similar reference numerals in the drawings represent the same or similar components. DETAILED DESCRIPTION

[0036] The utility model is described in further detail below in conjunction with the accompanying drawings.

[0037] like Figure 1 As shown, Figure 1 The present invention provides a schematic structural diagram of a wireless capacitive pen proposed in one aspect, the wireless capacitive pen is applied to an IOS device, wherein the wireless capacitive pen comprises a low-power Bluetooth chip and a key, an LED light group, a flexible printed circuit board (FPC) connector and a scroll switch respectively connected to the Bluetooth chip; when the wireless capacitive pen is in a powered-on state, the Bluetooth chip and the LED light group are turned on, the scroll switch is in a high-level state, and a PWM (Pulse Width Modulation) wave is output through the FPC connector, wherein the connection schematic diagram of the components of the FPC connector is as shown in FIG. Figure 2As shown; the PWM wave control component generates static electricity that simulates the body to realize the touch operation of IOS. The button establishes a touch connection with the IOS device through the touch operation on the IOS device, thereby realizing the touch operation of the wireless capacitive pen on the IOS device. It also uses a low-power Bluetooth chip as the main control, which has low power consumption and can also adapt to various IOS devices with higher configurations.

[0038] Furthermore, a wireless capacitive pen provided in one aspect of the utility model further includes: a charging management IC connected to the Bluetooth chip, the charging management IC being connected to the lithium battery in the wireless capacitive pen, wherein the connection diagram of the components in the charging management IC is as shown in Figure 3 As shown; the charging management IC is also connected to the Type-C interface on the wireless capacitive pen, wherein the connection diagram of the components of the Type-C interface is as shown Figure 4 As shown, Figure 4 The +5V of the Type-C interface Figure 3 +5V connection of the charge management IC in Figure 3 The VBAT of the charging management IC is connected to the positive electrode of the lithium battery in the wireless charging pen, and the lithium battery is quickly charged through the charging management IC and the Type-C interface; Figure 3 The CHG_STATE / BOOT1 of the charging management IC in the wireless stylus is connected to the Bluetooth chip to feedback to the MCU in the Bluetooth chip whether the charging of the lithium battery in the wireless stylus is completed.

[0039] Furthermore, a wireless capacitive pen provided in one aspect of the present invention further includes: a protection circuit connected to the lithium battery in the wireless capacitive pen, and a connection diagram of components of the protection circuit is shown in FIG. Figure 5 As shown, the protection circuit protects the lithium battery in the charging state or the use state, thereby extending the battery life.

[0040] Furthermore, a wireless capacitive pen provided in one aspect of the utility model further includes: a voltage management unit connected to the Bluetooth chip and the lithium battery in the wireless capacitive pen respectively, and a connection diagram of components of the voltage management unit is shown in FIG. Figure 6 As shown, a voltage management unit is set between the Bluetooth chip and the lithium battery. Since the power supply of the Bluetooth chip is 3.3V and the output voltage of the lithium battery is higher than 3.3V, a voltage management unit is needed to step down the output voltage of the lithium battery and output it to the Bluetooth chip in a stable voltage to achieve the purpose of stable voltage output to the Bluetooth chip.

[0041] Furthermore, one aspect of the utility model provides a wireless capacitive pen further comprising: a voltage detection circuit connected to the Bluetooth chip and the lithium battery in the wireless capacitive pen respectively, and a connection diagram of components of the voltage detection circuit is shown in FIG. Figure 7 As shown, the voltage detection circuit detects the voltage of the lithium battery and outputs the detected voltage of the lithium battery to the Bluetooth chip, so that the Bluetooth chip detects whether the lithium battery starts to be charged according to the voltage of the lithium battery, that is, the Bluetooth chip knows that the lithium battery has started to be charged, or the Bluetooth chip detects whether the voltage of the lithium battery is lower than 3V. If the voltage of the lithium battery is lower than 3V, the wireless capacitive pen is directly shut down to achieve automatic shutdown due to low voltage, thereby extending the battery life.

[0042] Furthermore, one aspect of the utility model provides a wireless capacitive pen further comprising: a power supply interface connected to the Bluetooth chip and the lithium battery in the wireless capacitive pen respectively, and a connection diagram of components of the power supply interface is shown in FIG. Figure 8 As shown, the VBAT of the power supply interface is connected to the positive electrode of the lithium battery, and B- and B+ are both connected to the lithium battery, so that the Bluetooth chip is powered by the lithium battery.

[0043] Furthermore, one aspect of the present invention provides a wireless capacitive pen further comprising: a power detection circuit connected to the lithium battery in the wireless capacitive pen, and a connection diagram of components of the power detection circuit is shown in FIG. Fig. 9 As shown, the power detection circuit is connected to the Bluetooth chip through ADC, and the power percentage of the lithium battery is transparently transmitted to the IOS device through the Bluetooth chip, wherein the pin BAT_ADC in the power detection circuit is connected to the Bluetooth chip, and VBAT is connected to the positive electrode of the lithium battery to detect the power percentage of the lithium battery. For example, the low-power Bluetooth chip reads the voltage data of the lithium battery through ADC, and then optimizes the logic of power increase and decrease through the voltage and power conversion algorithm, and finally transparently transmits the power percentage of the lithium battery to the IOS device through the Bluetooth chip, so that the IOS device receives the power percentage of the lithium battery, thereby displaying the power percentage and charging status icon of the lithium battery on the desktop widget of the IOS device, so that the user can understand the power percentage and charging status of the wireless capacitive pen through the IOS device.

[0044] Next, in this embodiment, the LED light group includes four LED lights. When the wireless capacitive pen is in a charging state or a power-on state, different numbers of LED lights are lit according to the power level of the lithium battery in the wireless capacitive pen. For example, the low-power Bluetooth chip reads the voltage data of the lithium battery through the ADC, and then optimizes the logic of power increase and decrease through the voltage and power conversion algorithm, and finally transmits the power percentage of the lithium battery to the IOS device through the Bluetooth chip; at the same time, the four LED lights will display different numbers of LED lights on and off according to the power percentage of the lithium battery. Fig.10 As shown, the Bluetooth chip is connected to the LED light group, that is, each LED light is connected to the Bluetooth chip respectively, wherein the connection diagram of the detailed components in each LED light is as shown in Fig.11 shown.

[0045] Furthermore, one aspect of the utility model provides a wireless stylus pen further comprising: a 32M crystal oscillator connected to the Bluetooth chip, such as Figure 1 and Fig.10 As shown, the internal clock of the low-power Bluetooth chip is calibrated by the 32M crystal oscillator.

[0046] exist Fig.10 The dotted line in the lower right corner is a connection diagram of the components of the slow charging circuit of the wireless capacitive pen. The VBAT in the dotted line in the lower right corner is connected to the positive electrode of the lithium battery of the wireless capacitive pen, and the lithium battery is normally slowly charged through the slow charging circuit.

[0047] Furthermore, one aspect of the utility model provides a wireless stylus pen further comprising: a debugging interface connected to the Bluetooth chip, such as Figure 1 As shown, the Bluetooth chip downloads and debugs the program in the Bluetooth chip through the debugging interface.

[0048] Following the above embodiments of the present invention, Figure 1In the structural diagram of the wireless capacitive pen shown, the low-power Bluetooth chip is a main module of the wireless capacitive pen, which is mainly responsible for Bluetooth communication, reading the voltage data of the lithium battery in the wireless capacitive pen, detecting the status of the buttons, outputting PWM waves, and controlling the entire wireless capacitive pen system. The low-power Bluetooth chip reads the voltage data of the lithium battery through ADC, and then optimizes the logic of power increase and decrease through the voltage and power conversion algorithm. Finally, the percentage of power of the lithium battery is transparently transmitted to the IOS device through the Bluetooth chip. At the same time, the four LED lights in the LED light group will display different numbers of LED lights on and off according to the power level of the lithium battery; the low-power Bluetooth chip will always detect the state of the button to determine whether the button is pressed. It can turn the machine on and off by distinguishing long press and short press. When the machine is turned on and the Bluetooth chip is in a connected state, the HID protocol (Human Interface Device protocol, a protocol for communication between computers and human-computer interaction devices) data is transparently transmitted according to the number of times the button is pressed, so as to realize the return to the main interface of the IOS device, open the task background and screenshot function lights; the low-power Bluetooth chip calibrates the internal clock of the Bluetooth chip through an external 32M crystal oscillator; the low-power Bluetooth chip downloads and debugs the program in the Bluetooth chip through the debugging interface; the low-power Bluetooth chip is powered by the lithium battery in the wireless pen.

[0049] like Fig.12 As shown, it is a schematic diagram of a system flow of the wireless capacitive pen proposed in one aspect of the utility model. Fig.12 In the embodiment, the wireless capacitive pen is powered on and is in the off state. Long press the button for 2s to turn it on, turn on the BLE (Bluetooth Low Energy) of the Bluetooth chip, turn on the LED light group, turn on the MOS and output PWM waves; when the wireless capacitive pen is connected to the charger and is in the charging state, the LED light group consisting of 4 LED lights will show different lighting states. Among them, when one of the four LED lights is red, it is used to indicate that the power of the lithium battery is too low as a warning. In the charging state, the lighting mode of the other three LED lights is as follows: when the power PP of the lithium battery is greater than 0 and less than 30% of the preset power threshold, the three LED lights are not lit; when the power PP of the lithium battery is greater than or equal to 30% of the preset power threshold and less than 70% of the preset power threshold, the first of the three LED lights is lit; when the power PP of the lithium battery is greater than or equal to 70% of the preset power threshold and less than 100% of the preset power threshold, the first and second of the three LED lights are lit; when the power PP of the lithium battery is equal to 100% of the preset power threshold (that is, charging is completed, corresponding to Fig.12When the charging state is reached, the three LED lights are all lit, so that the charging state is reflected by the lighting state of different LED lights.

[0050] If the scroll switch in the wireless capacitive pen detects that it has been stationary for 5 minutes, it will automatically shut down, otherwise it will remain powered on; after powering on, the LED light group will light up different numbers according to the level of power read and keep flashing for 30 seconds. If the Bluetooth connection is successful in the middle, the LED will stop flashing. When connected to Bluetooth, different operation effects can be achieved through the HID protocol according to the number of times the button is pressed; if Bluetooth is disconnected, the device will refresh to the just-powered state; if Fig.12 As shown in the figure, when the device is powered on and not charging, long pressing the button for more than 3s to turn it off or the voltage of the lithium battery is lower than 3V will also cause the wireless capacitive pen to shut down; in the charging state, the device will remain powered on, and only the BLE and LED lights will be turned on, and the button operation will no longer respond. After that, if charging is canceled (i.e. the charger is removed), the wireless capacitive pen will shut down immediately; to prevent non-human accidental startup, long press for 2s to turn it on, and then it will shut down after 3s. If you still do not release the button, it cannot be turned on. You need to release it and press it for 2s again to turn it on to prevent non-human accidental startup.

[0051] In this embodiment, when the wireless capacitive pen is in the power-on state, the display logic of the LED light group (flashing or always on) is as follows: D4 of the four LED lights is a red light, and D1, D2, and D3 are blue lights. When the power B of the lithium battery in the power-on state is less than or equal to 20% of the preset power threshold, D4 is on, and D3, D2, and D1 are off; when the power B of the lithium battery is greater than 20% of the preset power threshold and less than or equal to 40% of the preset power threshold, D4 is off, D3 is on, and D2 and D1 are off; when the power B of the lithium battery is greater than 40% of the preset power threshold and less than or equal to the preset power threshold, When the power threshold is 80%, D4 is off, D3 and D2 are on, and D1 is off; when the power B of the lithium battery is greater than 80% of the preset power threshold, D4 is off, D3, D2, and D1 are on. When the wireless capacitive pen is in the power-on state, the power status of the lithium battery is displayed by the on and off status of the four LED lights. At the same time, the pin GPIO5 in the Bluetooth chip is 470.588KHz, and the pin GPIO6 is 484.848KHz. Among them, MOS and PWM are turned on, which means that the wireless capacitive pen has a writing function, that is, it can perform touch operations on IOS devices.

[0052] In summary, the utility model provides a wireless capacitive pen, which is applied to IOS devices, wherein the wireless capacitive pen includes a low-power Bluetooth chip and a button, an LED light group, a flexible circuit board FPC connector and a scroll switch respectively connected to the Bluetooth chip; when the wireless capacitive pen is in a powered-on state, the Bluetooth chip and the LED light group are turned on, the scroll switch is in a high-level state, and a PWM wave is output through the FPC connector; the button establishes a touch connection with the IOS device through a touch operation on the IOS device, and by using a low-power Bluetooth chip as the main control, the power consumption is low, and it can also be adapted to various IOS devices with higher configurations.

[0053] Furthermore, the wireless capacitive pen also includes: a charging management IC connected to the Bluetooth chip, and the charging management IC is connected to the lithium battery in the wireless capacitive pen; the charging management IC is also connected to the Type-C interface on the wireless capacitive pen, so that the wireless capacitive pen can be quickly charged through the Type-C interface, and the charging current can reach up to 800mA.

[0054] Furthermore, the wireless capacitive pen also includes: a voltage detection circuit connected to the Bluetooth chip and the lithium battery in the wireless capacitive pen respectively, so as to output the detected voltage of the lithium battery to the Bluetooth chip, so that the Bluetooth chip detects whether the lithium battery has started charging or needs to be automatically shut down according to the voltage of the lithium battery, thereby allowing the Bluetooth chip to know that the lithium battery has started charging or to shut down the wireless capacitive pen.

[0055] Furthermore, the wireless capacitive pen also includes: a power detection circuit connected to the lithium battery in the wireless capacitive pen, the power detection circuit is connected to the Bluetooth chip via ADC, and the power percentage of the lithium battery is transparently transmitted to the IOS device via the Bluetooth chip, so that the power percentage and charging status icon of the lithium battery of the wireless capacitive pen are displayed on the desktop widget of the IOS device.

[0056] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-restrictive, and the scope of the present invention is limited by the appended claims rather than the above description, so it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any figure mark in the claims should not be regarded as limiting the claims involved. In addition, it is obvious that the word "comprising" does not exclude other units or steps, and the singular does not exclude the plural. Multiple units or devices stated in the device claim can also be implemented by one unit or device through software or hardware. The words first, second, etc. are used to indicate names, and do not indicate any particular order.

Claims

1. A wireless capacitive pen, which is applied to an IOS device, characterized in that: The wireless capacitive pen comprises a low-power Bluetooth chip and a key, an LED light group, a flexible circuit board (FPC) connector and a rolling switch respectively connected to the Bluetooth chip; When the wireless capacitive pen is in the power-on state, the Bluetooth chip and the LED light group are turned on, the scroll switch is in a high level state, and a PWM wave is output through the FPC connector; The button establishes a touch connection with the IOS device through a touch operation on the IOS device.

2. The wireless capacitive stylus pen according to claim 1, characterized in that: The wireless capacitive pen further comprises: a charging management IC connected to the Bluetooth chip, wherein the charging management IC is connected to a lithium battery in the wireless capacitive pen; The charging management IC is also connected to the Type-C interface on the wireless capacitive pen.

3. The wireless capacitive stylus pen according to claim 1, characterized in that: The wireless capacitive pen further comprises: a protection circuit connected to the lithium battery in the wireless capacitive pen, for protecting the lithium battery in a charging state or a use state.

4. The wireless capacitive stylus pen according to claim 1, characterized in that: The wireless capacitive pen further comprises: a voltage management unit connected to the Bluetooth chip and the lithium battery in the wireless capacitive pen respectively, so as to step down the output voltage of the lithium battery and output the voltage to the Bluetooth chip in a stable manner.

5. The wireless capacitive stylus pen according to claim 1, characterized in that: The wireless capacitive pen further comprises: a voltage detection circuit connected to the Bluetooth chip and the lithium battery in the wireless capacitive pen respectively, so as to output the detected voltage of the lithium battery to the Bluetooth chip.

6. The wireless capacitive stylus pen according to claim 1, characterized in that: The wireless capacitive pen further comprises: a power supply interface connected to the Bluetooth chip and a lithium battery in the wireless capacitive pen respectively, and the Bluetooth chip is powered by the lithium battery.

7. The wireless capacitive stylus pen according to claim 1, characterized in that: The wireless capacitive pen also includes: a power detection circuit connected to the lithium battery in the wireless capacitive pen, the power detection circuit is connected to the Bluetooth chip through ADC, and transmits the power percentage of the lithium battery to the IOS device through the Bluetooth chip.

8. The wireless capacitive stylus pen according to claim 1, characterized in that: The wireless capacitive pen further comprises: a 32M crystal oscillator connected to the Bluetooth chip, and the internal clock of the Bluetooth chip is calibrated by the 32M crystal oscillator.

9. The wireless capacitive stylus pen according to claim 1, characterized in that: The wireless capacitive pen further comprises: a debugging interface connected to the Bluetooth chip, and the Bluetooth chip downloads and debugs the program in the Bluetooth chip through the debugging interface.

10. The wireless capacitive stylus pen according to claim 1, characterized in that: The LED light group includes four LED lights. When the wireless capacitive pen is in a charging state or a power-on state, different numbers of LED lights are lit according to the power level of the lithium battery in the wireless capacitive pen.

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