CN-122026635-A - Method for realizing wireless charging of pens with different capacitances based on variable capacitance

CN122026635ACN 122026635 ACN122026635 ACN 122026635ACN-122026635-A

Abstract

The invention discloses a method for realizing wireless charging of different capacitance pens based on variable capacitance, which relates to the field of wireless charging of capacitance pens and comprises the following operation steps of S1, core component selection design, S2, initialization stage, S3, capacitance pen identification, S4, initial state judgment and adjustment start, S5, programmable capacitance adjustment and state synchronous detection, S6, optimal matching locking, and S7, dynamic monitoring and readjustment of a charging process. According to the method for realizing wireless charging of different capacitance pens based on the variable capacitance, the total capacitance C is changed by adjusting the capacitance value of the programmable capacitance C2, so that the resonance frequency of an LC transmitting circuit is adjusted to adapt to the inherent resonance frequency of the receiving end of the different capacitance pens, a wireless charging chip is responsible for detecting the connection and charging state of the capacitance pens, a singlechip is responsible for receiving state information and generating an adjusting instruction, the programmable capacitance C2 adjusts the capacitance value according to the instruction, and the three can cooperate to complete matching of the resonance frequency.

Inventors

JIN XIAOFENG
HU JISONG
WANG XIAODONG

Assignees

江苏盖睿健康科技有限公司

Dates

Publication Date: 20260512
Application Date: 20260128

Claims (9)

1. A method for realizing wireless charging of pens with different capacitances based on variable capacitance is characterized by comprising the following operation steps: s1, selecting a wireless charging chip, a singlechip, a fixed capacitor C1, a programmable capacitor C2 and a transmitting coil by adopting a core component; S2, in an initialization stage, after the multi-parameter health detection integrated machine is electrified, the singlechip configures parameters of a wireless charging chip, sets an initial value of a programmable capacitor C2, and the system enters a standby and circulating detection state to wait for the access of a capacitance pen; s3, in a capacitive pen identification stage, detecting the load change of a transmitting coil, eliminating interference to confirm the capacitive pen, and reporting state information of charging current and voltage to the single-chip microcomputer; s4, in the initial state judging and adjusting starting stage, the singlechip checks data, the charging current is compared with a target value, and if the difference value exceeds the range, the adjusting direction and the amplitude of the programmable capacitor C2 are determined, and the adjustment is started; S5, in a programmable capacitor adjustment and state synchronous detection stage, after the programmable capacitor C2 is adjusted, the stability is improved, new current is measured, the direction is changed before adjustment, the temperature of a transmitting coil is synchronously monitored, and the power is reduced when the threshold value is exceeded; S6, in the best matching and locking stage, repeatedly adjusting and detecting until the current reaches a peak value, locking the programmable capacitor C2 value and the charging power, and entering into efficient charging; And S7, in the stage of dynamic monitoring and readjusting in the charging process, the current monitored in the charging process is reduced to 80% or less, the charging is stopped when the charging is full, and the programmable capacitor C2 is reset to wait for the next charging.
2. The method for realizing wireless charging of different capacitance pens based on variable capacitance according to claim 1, wherein in S1, a wireless charging chip selects a chip type which supports a wide resonance frequency range, has a high-precision current and voltage detection function and supports two-way communication, and meanwhile has flexible power adjustment capability, and when the wireless charging chip is matched with different capacitance pens, the transmitting power can be dynamically adjusted according to resonance matching conditions; The singlechip is required to select a singlechip model which has enough IO interfaces, supports an I2C communication protocol, has moderate operation speed and lower power consumption; The capacitor comprises a fixed capacitor C1 and a programmable capacitor C2, wherein the fixed capacitor C1 and the programmable capacitor C2 form a total capacitor C of the LC circuit of the wireless charging transmitting end, the fixed capacitor C1 provides a basic capacitance value for the LC circuit, the programmable capacitor C2 is used for fine tuning the size of the total capacitor C so as to change the resonant frequency of the LC circuit, the fixed capacitor C1 needs to select a capacitor type with high stability and small temperature coefficient and comprises a high-frequency ceramic capacitor and a metallized film capacitor, and the capacitance value of the fixed capacitor C1 is the middle interval of the total capacitor required by a common capacitor pen; the parameter design of the transmitting coil is matched with the capacitance value ranges of the fixed capacitor C1 and the programmable capacitor C2.
3. The method for realizing wireless charging of different capacitance pens based on variable capacitance according to claim 1, wherein the step S2 comprises the following steps: S201, after a multi-parameter health detection integrated machine is electrified and started, a wireless charging system enters an initialization stage, firstly, a singlechip sends an initialization instruction to a wireless charging chip, and working parameters of the wireless charging chip are configured, wherein the working parameters comprise an allowable range of charging voltage, detection precision of charging current, communication baud rate and initial values of transmitting power; S202, simultaneously, the singlechip sends an initial adjustment instruction to the programmable capacitor C2, adjusts the capacitance value of the programmable capacitor C2 to a preset initial value, wherein the initial value is set based on the resonance frequency of a main-stream capacitance pen on the market, and the fixed capacitor C1 keeps the capacitance value unchanged at the stage and forms an initial value of the total capacitor C together with the initial value of the programmable capacitor C2 so as to enable the LC circuit to form the initial resonance frequency; S203, after initialization is completed, the wireless charging chip enters a standby state, continuously monitors the load change of the transmitting coil, and waits for the capacitive pen to be connected; The singlechip enters a cycle detection state, receives state data sent by the wireless charging chip in real time, and prepares for the subsequent identification and adjustment of the capacitance pen.
4. The method for realizing wireless charging of different capacitance pens based on variable capacitance according to claim 1, wherein the step S3 comprises the following steps: S301, when a user places a capacitance pen in a wireless charging area of the multi-parameter health detection integrated machine, a receiving coil of the capacitance pen enters an electromagnetic radiation range of a transmitting coil, so that the load impedance of the transmitting coil changes, and the wireless charging chip acquires current and voltage signals at two ends of the transmitting coil in real time through a built-in current sensor and a built-in voltage sensor, so that the load change is captured; S302, the wireless charging chip processes the acquired current and voltage signals, namely firstly, high-frequency interference in the signals is removed through a filter circuit, then the weak signals are amplified through an amplifying circuit, finally, signal characteristics are analyzed through a built-in recognition algorithm, the recognition algorithm is used for judging whether load change is caused by a compatible wireless charging capacitance pen, if the load change is a metal foreign matter, the wireless charging chip sends out an alarm signal and stops energy emission, overheating of the foreign matter is avoided, if the load change is a metal foreign matter, the wireless charging chip generates state information which is accessed by the capacitance pen, packages the current charging current value, the charging voltage value and the temperature value of a transmitting coil, and reports the current charging current value, the charging voltage value and the temperature value of the transmitting coil to the singlechip through an I2C communication protocol.
5. The method for realizing wireless charging of different capacitance pens based on variable capacitance according to claim 1, wherein the step S4 comprises the following steps: S401, after receiving a status data packet reported by a wireless charging chip, the singlechip firstly checks the data, confirms that no error occurs in the data in the transmission process through a CRC (cyclic redundancy check) algorithm, and after the data passes the check, the singlechip extracts a charging current value in the data packet and compares the charging current value with an optimal charging current target value preset in the singlechip; S402, if the difference value between the current charging current value and the optimal charging current target value is in an allowable range, the singlechip judges that the resonant frequency of the LC circuit at the transmitting end is well matched with the inherent resonant frequency of the receiving end of the capacitance pen, adjustment is not needed, the singlechip sends an instruction for maintaining the current working parameters to the wireless charging chip, and simultaneously sends an instruction for locking the current capacitance value to the programmable capacitance C2, so that the system enters a stable charging state; S403, if the current charging current value is lower than the optimal charging current target value and the difference value exceeds the allowable range, the singlechip judges that the resonance frequency has deviation and needs to start an adjustment flow, and at the moment, the singlechip determines the preliminary adjustment direction of the programmable capacitor C2 according to the magnitude of the current difference value, if the current difference value is larger, the deviation between the total capacitor C and the ideal value is larger, larger-amplitude adjustment is needed, and if the current difference value is smaller, only small-amplitude fine adjustment is needed.
6. The method for realizing wireless charging of different capacitance pens according to claim 5, wherein in S402, the allowable range is set based on charging efficiency, and a smaller difference indicates a better resonance matching.
7. The method for realizing wireless charging of different capacitance pens based on variable capacitance according to claim 1, wherein the step S5 comprises the following steps: S501, the singlechip sends a digital control signal to the programmable capacitor C2 according to the preliminarily determined adjusting direction and amplitude, the programmable capacitor C2 receives the signal, an internal switch circuit acts to change the number of capacitor units of an access circuit, so that the adjustment of a capacitance value is realized, and after the adjustment is finished, the programmable capacitor C2 sends a feedback signal for finishing the adjustment to the singlechip to inform the singlechip that the current capacitance value is updated; s502, after receiving the feedback signal after the adjustment, the singlechip enters a stabilization period for enabling the resonant frequency of the LC circuit to be stabilized at a new value, avoiding errors in subsequent state detection caused by unstable frequency, and after the stabilization period is finished, the singlechip sends an instruction for reading the current state to the wireless charging chip to request the chip to acquire and report the adjusted charging current value, voltage value and coil temperature value; S503, after receiving the instruction, the wireless charging chip immediately starts a new round of state acquisition, the acquired data is reported to the singlechip through an I2C protocol after being processed, the singlechip extracts a new charging current value, and the current value is compared with the current value before adjustment, if the new current value rises more than before adjustment, the current adjustment direction is correct, the singlechip continues to adjust next time according to the direction, if the new current value falls more than before adjustment, the adjustment direction is incorrect, the singlechip immediately changes the adjustment direction, and the capacitance value of the programmable capacitor C2 is reversely adjusted; and S504, synchronously monitoring the temperature value of the transmitting coil by the singlechip, if the temperature value exceeds a preset safety threshold, suspending the adjustment of the programmable capacitor C2 by the singlechip, simultaneously sending an instruction for reducing the transmitting power to the wireless charging chip, and restarting the adjustment flow after the temperature is reduced to a safety range.
8. The method for realizing wireless charging of different capacitance pens based on variable capacitance according to claim 1, wherein the step S6 comprises the following steps: S601, repeating the processes of programmable capacitance adjustment and state synchronous detection by the singlechip, continuously trimming the capacitance value of the programmable capacitance C2, and comparing a new charging current value with a current value of the last time by the singlechip every time the adjustment and the detection are completed, and judging whether the current is still rising; S602, after a certain adjustment, the singlechip finds that the charging current value reaches a peak value, namely, when the adjustment is continued according to the current direction, the charging current is not increased, but is reduced, at the moment, the singlechip judges that the optimal total capacitance C value is found, the resonant frequency of the corresponding LC circuit is completely matched with the inherent resonant frequency of the receiving end of the capacitance pen, and the charging efficiency is highest; and S603, the singlechip sends an instruction for locking the current capacitance value to the programmable capacitor C2, inhibits the capacitance value of the programmable capacitor C from changing again, and simultaneously sends an instruction for maintaining the current transmitting power to the wireless charging chip, so that the charging process is ensured to be stable, and the charging stage is stabilized.
9. The method for realizing wireless charging of different capacitance pens based on variable capacitance according to claim 8, wherein in S7, the method specifically comprises the following steps: S701, in a stable charging stage, the singlechip enters a dynamic monitoring mode, and continuously acquires charging current value, voltage value and position change related data of the capacitance pen through the wireless charging chip; S702, when the singlechip detects that the charging current value is reduced to be less than 80% of the optimal value, judging that resonance matching has deviation and needs to be adjusted again, at the moment, the singlechip sends a command of unlocking the capacitance value to the programmable capacitance C2, and simultaneously starts a new round of adjustment and detection flow, and the capacitance value of the programmable capacitance C2 is adjusted again according to the steps until the charging current is restored to the optimal value, and the capacitance value is locked again; And S703, in the charging process, if the singlechip detects that the capacitance pen is fully charged through the wireless charging chip, sending an instruction for stopping energy emission to the wireless charging chip, and simultaneously recovering the capacitance value of the programmable capacitor C2 to an initial value so as to be ready for the next charging.

Description

Method for realizing wireless charging of pens with different capacitances based on variable capacitance Technical Field The invention relates to the field of wireless charging of capacitance pens, in particular to a method for realizing wireless charging of different capacitance pens based on a variable capacitance. Background In the current field of electronic equipment, a multi-parameter health detection integrated machine is used as equipment integrating multiple health detection functions, and is widely applied to scenes such as families, community medical service centers and the like. In the use process of the multi-parameter health detection integrated machine, the capacitance pen is an important auxiliary operation accessory, and a user can accurately click a touch screen of the integrated machine through the capacitance pen to finish operations such as detection parameter setting, detection result confirmation and the like. In order to ensure continuous availability of the capacitance pen, the multi-parameter health detection integrated machine generally integrates a wireless charging function and provides convenient charging service for the capacitance pen. However, in the prior art, most wireless charging capacitance pens adapted to the multi-parameter health detection integrated machine are customized products. The current situation is caused by the fact that when different manufacturers design capacitance pens, the parameters of the internal receiving coils of the capacitance pens have obvious differences, the receiving coils of the capacitance pens of different manufacturers can be different in number of turns, wire diameter and winding mode, and the differences directly lead to different natural resonant frequencies of the receiving ends of different capacitance pens. On the contrary, in the wireless charging transmitting circuit of the multi-parameter health detection integrated machine end, the capacitance value in the LC resonance circuit of the core is usually fixed, namely the resonance frequency of the transmitting end is single and not adjustable. Therefore, it is necessary to provide a method for realizing wireless charging of different capacitance pens based on variable capacitance to solve the above-mentioned problems. Disclosure of Invention The invention mainly aims to provide a method for realizing wireless charging of pens with different capacitances based on variable capacitance, which can effectively solve the problems in the background technology. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: A method for realizing wireless charging of pens with different capacitances based on variable capacitance comprises the following operation steps: s1, selecting a wireless charging chip, a singlechip, a fixed capacitor C1, a programmable capacitor C2 and a transmitting coil by adopting a core component; S2, in an initialization stage, after the multi-parameter health detection integrated machine is electrified, the singlechip configures parameters of a wireless charging chip, sets an initial value of a programmable capacitor C2, and the system enters a standby and circulating detection state to wait for the access of a capacitance pen; s3, in a capacitive pen identification stage, detecting the load change of a transmitting coil, eliminating interference to confirm the capacitive pen, and reporting state information of charging current and voltage to the single-chip microcomputer; s4, in the initial state judging and adjusting starting stage, the singlechip checks data, the charging current is compared with a target value, and if the difference value exceeds the range, the adjusting direction and the amplitude of the programmable capacitor C2 are determined, and the adjustment is started; S5, in a programmable capacitor adjustment and state synchronous detection stage, after the programmable capacitor C2 is adjusted, the stability is improved, new current is measured, the direction is changed before adjustment, the temperature of a transmitting coil is synchronously monitored, and the power is reduced when the threshold value is exceeded; S6, in the best matching and locking stage, repeatedly adjusting and detecting until the current reaches a peak value, locking the programmable capacitor C2 value and the charging power, and entering into efficient charging; And S7, in the stage of dynamic monitoring and readjusting in the charging process, the current monitored in the charging process is reduced to 80% or less, the charging is stopped when the charging is full, and the programmable capacitor C2 is reset to wait for the next charging. Preferably, in the step S1, the wireless charging chip selects a chip type that supports a wide resonant frequency range, has a high-precision current and voltage detection function, supports bidirectional communication, and simultaneously needs to have flexible power adjustment capability, and when be