Low-power-consumption charging control method adaptive to standby mode

Abstract

The invention discloses a low-power-consumption charging control method adaptive to a standby mode, and relates to the technical field of low-power-consumption charging control, and the method comprises the following steps: S1, collecting the charging voltage, current and temperature parameters of a battery in real time through a detection circuit integrated by an ASIC in a chip, the detection circuit controls the detection error precision of the charging voltage to be within 1% through a built-in calibration module; s2, processing an input power supply through a 4.5-6V wide voltage adaptation circuit, and judging trickle, constant current, constant voltage and full charge turn-off stages in combination with a preset threshold value and temperature; and S3, the control module adjusts the module state through the power management circuit, cuts off unnecessary module power supply during standby to enable the quiescent current to be smaller than or equal to 5 microamperes, and triggers a protection standby mode according to an abnormal signal. Through the hardware interrupt circuit, low-power-consumption control of the self-adaptive standby mode is achieved, the problem that the power consumption is high when the charging circuit is in a standby state is solved, the standby power consumption of a chip is reduced, and charging can be rapidly recovered in the standby state.

Description

Technical Field

[0001] The present invention relates to the technical field of low-power charging control, and in particular to a low-power charging control method in an adaptive standby mode. Background Art

[0002] The popularity of portable electronic devices and the advancement of battery technology are driving higher demands on charging control circuits for low power consumption, high integration, safety, and adaptability. Traditional charging control solutions commonly suffer from the following issues: First, they rely on discrete components such as external voltage comparators and protection chips, resulting in high material costs and complex PCB layouts. Second, they suffer from high quiescent current in standby mode, resulting in insufficient power consumption control. Third, they have limited adaptability to a wide range of input voltages, and the accuracy of charging parameter detection struggles to meet the demands of high-precision battery management. Fourth, the protection mechanism responds slowly under abnormal operating conditions, potentially posing safety risks.

[0003] Patent CN109713751B discloses a battery low-power standby control circuit and method. This patent enables switching between low-power standby mode and normal operating mode at any time, and automatically exits low-power standby mode during charging. In low-power standby mode, standby power consumption is effectively reduced, battery life is effectively extended, and ultimately the purpose of low-power standby is achieved. The touch button can serve as a trigger signal for entering and exiting low-power standby mode, and can also realize normal touch button functions.

[0004] The above patent effectively reduces standby power consumption and extends battery life through switchable low-power standby mode and normal working mode, while giving touch buttons dual functions; however, it does not study how to dynamically adjust the standby strategy based on real-time charging parameters during the charging process, accurately match the low-power requirements of the charging stage, and develop an adaptive protection mechanism to deal with abnormal conditions such as short circuits, overvoltage, and overheating that may occur during the charging process.

[0005] To this end, the present application proposes a low-power charging control method for an adaptive standby mode that can achieve ultra-low power consumption control by using hardware interrupt wake-up technology under multiple real-time protection mechanisms. Summary of the Invention

[0006] The purpose of the present invention is to provide a low-power charging control method in an adaptive standby mode to solve the technical problems that the traditional charging control scheme proposed in the above background technology relies on discrete components such as external voltage comparators and protection chips, resulting in high material costs, complex PCB layout, large static current in standby mode, and insufficient power consumption control.

[0007] To achieve the above object, the present invention provides the following technical solution: a low-power charging control method in an adaptive standby mode, comprising the following steps:

[0008] S1. Utilize the detection circuit integrated in the chip's ASIC to collect battery charging voltage, current, and temperature parameters in real time. The detection circuit uses a built-in calibration module to control the charging voltage detection error accuracy to within 1%.

[0009] S2, processes the input power through a 4.5-6V wide voltage adapter circuit, and determines the trickle current, constant current, constant voltage and full charge shutdown stages based on the preset threshold and temperature;

[0010] S3. The control module adjusts the module status through the power management circuit, cuts off the power supply to non-essential modules in standby mode to make the static current ≤ 5μA, and triggers the protection standby mode according to the abnormal signal;

[0011] S4. In standby mode, the output is cut off. The hardware interrupt circuit in the chip detects that the charging current is lower than 1% of the battery capacity. When the wake-up condition is met, the hardware interrupt circuit wakes up the chip in no more than 100μs to resume charging.

[0012] Preferably, the ASIC integrates the voltage comparator, analog-to-digital converter, and control logic unit required for charging control on the same chip substrate through layout and routing, with input and output pins distributed around the chip, and the voltage comparator, analog-to-digital converter, and control logic unit connected by metal wires;

[0013] The input pin of the voltage comparator is directly connected to the external detection circuit, and the output pin is connected to the control module through an internal wire. The wire connects the input power supply to the chip power pin, the positive and negative poles of the battery to the chip charging input pin, the LED to the status pin and a series resistor to ground.

[0014] Preferably, the wide voltage adaptation circuit is processed by a multi-stage voltage stabilization circuit in the chip, and the multi-stage voltage stabilization circuit includes a front-end anti-reverse connection diode circuit, an LC filter circuit and a DC-DC voltage stabilization circuit. The anode of the anti-reverse connection diode circuit is connected to the positive pin of the input power socket through a PCB wire, and the cathode is connected to one end of the inductor of the LC filter circuit through a wire; the other end of the LC filter circuit is connected to one end of the ceramic capacitor and the input pin of the DC-DC voltage stabilization circuit through a wire, and the other end of the ceramic capacitor is grounded through a wire;

[0015] The DC-DC voltage regulator circuit adopts a synchronous buck topology. The gate of the internal switch tube is connected to the output pin of the PWM control chip through a wire. The power pin of the PWM control chip is connected to the cathode of the anti-reverse diode through a wire. The feedback pin of the PWM control chip is connected to the voltage divider circuit of the power input pin of the charging module through a wire. The PWM mode dynamically adjusts the duty cycle according to the input voltage and load changes.

[0016] Preferably, in the charging voltage detection, the analog input pin of the 24-bit Σ-Δ analog-to-digital converter in the ASIC is connected to the output of the programmable gain amplifier via a wire, the input of the programmable gain amplifier is connected to the battery voltage detection circuit via a wire, the gain control pin of the programmable gain amplifier is connected to the GPIO pin of the control module via a wire, the control module outputs different level combinations to the GPIO pin according to the battery voltage range, and controls the amplification factor of the programmable gain amplifier via an internal decoding circuit;

[0017] The reference voltage pin of the analog-to-digital converter is connected to the output end of the bandgap reference source in the chip through a wire, and the digital output pin of the analog-to-digital converter is connected to the data input interface of the control module through an internal bus; combined with the calibration data of the bandgap reference source and the analog-to-digital converter at different temperatures before leaving the factory, the detection results are adjusted through a digital calibration algorithm.

[0018] Preferably, in the fully charged shutdown stage, the PWM output pin of the control module is connected to the input end of the drive circuit via a wire, and the output end of the drive circuit is connected to the gate of the power MOSFET of the charging output circuit via a wire; the source of the MOSFET is connected to the positive electrode of the charging power supply via a wire, and the drain is connected to the positive electrode of the battery via a wire;

[0019] In the later stage of constant-voltage charging, the control module continuously reads the current data output by the analog-to-digital converter through the internal bus. When the current drops below 1% of the battery capacity and lasts for 10 minutes, the control module sends a low-level signal to the drive circuit through the PWM output pin. The drive circuit outputs a low level and the MOSFET is turned off. The control module outputs a signal to the LED drive circuit through another GPIO pin to control the LED to turn off and flash slowly.

[0020] Preferably, the source of the PMOS switch tube of the power management circuit is connected to the power input pin of the chip via a wire, and the drain is connected to the power input pins of non-essential modules via wires; in standby mode, the control module sends a low-level signal to the PMOS gate via an internal drive circuit, and the power pin of the analog-to-digital converter is connected to a turnable power switch via a wire;

[0021] The power pin of the voltage comparator is connected to the output of the low-power LDO regulator in the chip through a wire. The LDO input is connected to the chip power supply and the output is connected to the power pin of the voltage comparator and the control module circuit through a wire. When the logic unit inside the control module enters the sleep state in standby mode, the power pins of the interrupt processing unit and the register are connected to the output of the LDO regulator through an independent low-power line.

[0022] Preferably, the positive and negative input terminals of the current detection amplifier in the ASIC are connected to the two ends of the sampling resistor through wires, the sampling resistor is connected in series in the charging circuit, and the output terminal of the current detection amplifier is connected to the external interrupt pin of the control module through a wire;

[0023] When the voltage difference across the sampling resistor exceeds the short-circuit threshold, the current detection amplifier outputs a high-level signal to the interrupt pin of the control module. The control module sends a control signal to the drive circuit through the internal bus within 20μs to turn off the charging output drive circuit. The control module starts the internal 1s timer. If the voltage difference across the sampling resistor is higher than the threshold within 1s, the control module cuts off the power supply to non-essential circuits through the power management circuit.

[0024] Preferably, the detection circuits of the negative and positive electrodes of the battery are connected to the input ends of the undervoltage protection detection circuit through wires. When the battery voltage is lower than the undervoltage threshold, the undervoltage protection detection circuit sends a low-level signal to the interrupt pin of the control module through the wire. The control module calls the trickle charging program through the internal bus. The PWM output pin of the trickle charging program sends a duty cycle signal to the drive circuit, and trickle charging is performed with a current of 5% of the battery capacity. If the battery voltage continues to be lower than the undervoltage threshold for 10 minutes, the control module determines that the battery is abnormal and turns off the power supply of the trickle charging circuit through the power management circuit. When the voltage monitoring circuit powered by an independent low-power power supply detects that the battery voltage has recovered to above the undervoltage threshold, the control module wakes up the battery through the hardware interrupt circuit.

[0025] Preferably, the output end of the on-chip temperature sensor is connected to the ADC input pin of the control module via a wire, the control pin of the clock generator is connected to the control module, the input end of the heat dissipation control circuit is connected to the control module, and the output end of the heat dissipation control circuit is connected to the chip heat dissipation pin drive circuit via a wire;

[0026] When the temperature value read by the control module exceeds the preset threshold, a signal is sent to the power management circuit and the heat dissipation control circuit through the internal bus. The power management circuit reduces the module operating frequency by adjusting the output frequency of the clock generator.

[0027] Preferably, the interrupt pin of the control module is connected to the output end of the VCC overvoltage protection detection circuit, and the input end of the VCC overvoltage protection detection circuit is connected to the VCC power pin of the chip through a wire. When it is detected that the VCC voltage exceeds the preset overvoltage value, the detection circuit sends a high-level signal to the interrupt pin of the control module through the wire, and the control module cuts off the MOSFET switch of the charging input circuit through the driving circuit, and the control module outputs an alarm signal through another GPIO pin; when the detection circuit continuously monitors and sends a low-level signal to the interrupt pin of the control module to indicate that the VCC voltage has returned to the normal range, the control module timer is delayed by 500ms, and the control module wakes up through the interrupt to re-detect the input voltage and resume charging.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] 1. The present invention realizes low-power control in adaptive standby mode through a hardware interrupt circuit, solves the problem of high power consumption of the charging circuit when in standby mode, reduces the standby power consumption of the chip, and can quickly resume charging in the standby state;

[0030] 2. This invention integrates a voltage comparator, analog-to-digital converter, and control logic unit on the same chip substrate through an ASIC, achieving multi-functional and highly integrated design. This solves the problems of high material costs and large PCB layout area in traditional charging circuits and simplifies circuit design.

[0031] 3. This invention uses a wide voltage adaptation circuit to achieve wide voltage adaptation and high-precision charging parameter detection, solving the problems of narrow input voltage range and large charging voltage detection errors, and improving the charging circuit's compatibility with different input power sources.

[0032] 4. The present invention realizes real-time monitoring and rapid protection of abnormal conditions during the charging process through the undervoltage protection detection circuit, solves the problem of safety hazards caused by abnormal conditions during the charging process, and improves the reliability and safety of the charging system. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a schematic diagram of the ASIC chip architecture of the present invention;

[0034] Figure 2 This is a schematic diagram of the chip peripheral connection circuit of the present invention;

[0035] Figure 3 This is a schematic diagram of the VCC overvoltage protection process of the present invention;

[0036] Figure 4 This is a schematic diagram of the wide voltage adaptation circuit structure of the present invention. DETAILED DESCRIPTION

[0037] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0038] See also Figure 1 、 Figure 2 、 Figure 3 and Figure 4 The present invention provides an embodiment of a low-power charging control method in an adaptive standby mode, comprising the following steps:

[0039] S1. Utilize the detection circuit integrated in the chip's ASIC to collect battery charging voltage, current, and temperature parameters in real time. The detection circuit uses a built-in calibration module to control the charging voltage detection error accuracy to within 1%.

[0040] S2, processes the input power through a 4.5-6V wide voltage adapter circuit, and determines the trickle current, constant current, constant voltage and full charge shutdown stages based on the preset threshold and temperature;

[0041] S3. The control module adjusts the module status through the power management circuit, cuts off the power supply to non-essential modules in standby mode to make the static current ≤ 5μA, and triggers the protection standby mode according to the abnormal signal;

[0042] S4: The output is cut off in standby mode. The hardware interrupt circuit in the chip detects that the charging current is less than 1% of the battery capacity. When the wake-up condition is met, the hardware interrupt circuit wakes up the chip in no more than 100μs to resume charging.

[0043] The ASIC integrates the voltage comparator, analog-to-digital converter, and control logic unit required for charging control on the same chip substrate through layout and routing. Input and output pins are distributed around the chip, and the voltage comparator, analog-to-digital converter, and control logic unit are connected by metal wires. The input pin of the voltage comparator is directly connected to the external detection circuit, and the output pin is connected to the control module via internal wires. The wires connect the input power supply to the chip power pin, the positive and negative terminals of the battery to the chip charging input pin, and the LED to the status pin, and are connected in series with a resistor to ground.

[0044] Taking the SG802 series barometric pressure sensor as an example, in the system's peripheral application circuit, the ASIC chip's power input pin is connected via wires to both ends of the input filter capacitor, with one end connected to the pin and the other to ground. The charging output pin is connected via wires to one end of the energy storage inductor, the other end of which is connected to the positive terminal of the battery, with the negative terminal of the battery grounded. The status indicator LED is connected via wires to the chip's status pin and connected in series with a current-limiting resistor before being grounded. Due to the ASIC chip's high level of integration, no external voltage comparator or protection chip is required, requiring only a small number of peripheral components, reducing material costs and PCB layout area.

[0045] First, connect the positive and negative poles of the battery to the "+" and "-" pins of the chip respectively. The chip uses an ASIC-designed detection circuit, which includes a 24-bit Σ-Δ analog-to-digital converter and a programmable gain amplifier (PGA). The PGA automatically adjusts the amplification factor according to the initial battery voltage, filters the battery voltage and current signals, and inputs them into the analog-to-digital converter, converting them into digital signals for analysis by the control module.

[0046] Then, the control module compares the collected voltage and current with preset thresholds based on the analog signal processing and digital logic judgment principles within the chip. The conditioned battery voltage signal is input to one input terminal of the comparator, and the constant voltage charging threshold reference voltage is input to the inverting terminal. If the battery voltage signal is higher than the reference voltage, the comparator outputs a high level, and the control module determines that the constant voltage charging phase has begun. The conditioned current-converted voltage signal is input to the non-inverting terminal of another comparator, and the constant current charging threshold reference voltage is input to the inverting terminal. If the current signal is higher than the reference voltage, the comparator outputs a high level, the charging current is maintained at 1C of the battery capacity, and the voltage gradually increases. The control module determines that the constant current charging phase has begun. If the current signal is lower than the reference voltage and lower than the trickle threshold \(0.1V\), it is determined to be trickle charging. When the external device temporarily stops the power request and needs to enter standby mode, the control module sends a command to the power management circuit, which uses the PMOS switch tube to cut off the power supply to non-essential modules such as the charging pulse generation module and the voltage regulation auxiliary module, retaining only the basic power supply of the detection circuit and the control module, and the chip quiescent current is reduced to ≤5μA.

[0047] Finally, when the detection circuit detects that the battery voltage is lower than the wake-up threshold through the hardware interrupt circuit, the voltage comparator output level jumps, generating an interrupt trigger signal. The interrupt trigger signal is connected to the hardware interrupt pin of the chip through PCB wiring and input into the interrupt controller inside the chip. The interrupt controller detects the pin level change, identifies it as a valid interrupt request, and sends a wake-up instruction to the control module through the internal bus. After receiving the wake-up instruction, the control module stops the low-power operation in standby mode and restores power to each module. Subsequently, the control module reads the interrupt flag register, confirms that it is a voltage wake-up event, calls the initialization program, restarts the analog-to-digital converter and signal conditioning circuit, initializes the register state, starts the normal charging process judgment, and restores the constant current charging mode.

[0048] See also Figure 1 、 Figure 3 and Figure 4The present invention provides an embodiment of a low-power charging control method in an adaptive standby mode, wherein the wide voltage adaptation circuit is processed by a multi-stage voltage stabilization circuit within the chip, the multi-stage voltage stabilization circuit including a front-end anti-reverse diode circuit, an LC filter circuit, and a DC-DC voltage stabilization circuit. The anode of the anti-reverse diode circuit is connected to the positive pin of the input power socket via a PCB wire, and the cathode is connected to one end of the inductor of the LC filter circuit via a wire; the other end of the LC filter circuit is connected to one end of a ceramic capacitor and the input pin of the DC-DC voltage stabilization circuit via a wire, and the other end of the ceramic capacitor is grounded via a wire; the DC-DC voltage stabilization circuit adopts a synchronous buck topology, the gate of the internal switch tube is connected to the output pin of the PWM control chip via a wire, the power pin of the PWM control chip is connected to the cathode of the anti-reverse diode via a wire, and the feedback pin of the PWM control chip is connected to the voltage divider circuit of the power input pin of the charging module via a wire, and the PWM mode dynamically adjusts the duty cycle according to changes in the input voltage and load;

[0049] In the charging voltage detection, the analog input pin of the 24-bit Σ-Δ analog-to-digital converter in the ASIC is connected to the output of the programmable gain amplifier via a wire, the input of the programmable gain amplifier is connected to the battery voltage detection circuit via a wire, the gain control pin of the programmable gain amplifier is connected to the GPIO pin of the control module via a wire, the control module outputs different level combinations to the GPIO pin according to the battery voltage range, and controls the amplification factor of the programmable gain amplifier via an internal decoding circuit; the reference voltage pin of the analog-to-digital converter is connected to the output of the bandgap reference source in the chip via a wire, and the digital output pin of the analog-to-digital converter is connected to the data input interface of the control module via an internal bus; the detection result is adjusted using a digital calibration algorithm based on the calibration data of the bandgap reference source and the analog-to-digital converter at different temperatures before leaving the factory;

[0050] Furthermore, a sampling resistor is first connected in series in the charging circuit, and both ends of the sampling resistor are connected to the positive and negative input terminals of the current detection amplifier in the ASIC; before the sampling resistor voltage difference is detected, the calibration module calibrates the current detection amplifier to ensure accurate short-circuit threshold detection; when the charging circuit is accidentally short-circuited, the voltage difference across the sampling resistor instantly exceeds the short-circuit threshold.

[0051] Then, the current detection amplifier outputs a high-level signal to the external interrupt pin of the control module. The control module sends a control signal to the drive circuit through the internal bus within 20μs. The drive circuit is an intermediate circuit connecting the control module and the power MOSFET. Its function is to convert the signal of the control module into a level signal suitable for driving the MOSFET. The drive circuit outputs a low-level signal to the gate of the power MOSFET in the charging output circuit. The conduction of the power MOSFET depends on the voltage difference between the gate and the source. When the gate receives a low-level signal, Vgs is lower than the conduction threshold of the MOSFET, and the conductive channel inside the MOSFET cannot be formed, thus entering the cut-off state. Therefore, the charging output circuit is disconnected, and the current cannot pass, thereby cutting off the charging output.

[0052] Finally, the control module starts the internal 1s timer. If the sampling resistor voltage difference is still higher than the threshold within 1s, the control module further cuts off the power supply to non-essential circuits through the power management circuit and enters deep sleep mode. If the sampling resistor voltage difference is lower than the threshold, the short circuit is eliminated, and the detection circuit triggers a hardware interrupt to wake up the chip. The control module re-checks the charging circuit status and resumes the charging preparation process if it is normal.

[0053] See also Figure 1 、 Figure 2 and Figure 3 The present invention provides an embodiment of a low-power charging control method in an adaptive standby mode. In the fully charged shutdown phase, a PWM output pin of a control module is connected to an input of a drive circuit via a wire, and an output of the drive circuit is connected to a gate of a power MOSFET in a charging output circuit via a wire. The source of the MOSFET is connected to a positive electrode of a charging power source via a wire, and the drain is connected to a positive electrode of a battery via a wire. In the later stage of the constant voltage charging phase, the control module continuously reads current data output by an analog-to-digital converter via an internal bus. When the current drops below 1% of the battery capacity and lasts for 10 minutes, the control module sends a low-level signal to the drive circuit via the PWM output pin. The drive circuit outputs a low level, turning off the MOSFET. The control module outputs a signal to an LED drive circuit via another GPIO pin to control the LED to turn off and flash slowly.

[0054] The source of the PMOS switch tube of the power management circuit is connected to the chip power input pin via a wire, and the drain is connected to the power input pins of non-essential modules via wires. In standby mode, the control module sends a low-level signal to the PMOS gate via an internal drive circuit, and the power pin of the analog-to-digital converter is connected to a turn-off power switch via a wire. The power pin of the voltage comparator is connected to the output of a low-power LDO regulator in the chip via a wire. The LDO input is connected to the chip power supply, and the output is connected to the voltage comparator power pin and the control module circuit via a wire. When the logic unit inside the control module enters a dormant state in standby mode, the power pins of the interrupt processing unit and the register are connected to the output of the LDO regulator via independent low-power lines.

[0055] Furthermore, first, the input end of the undervoltage protection detection circuit is connected to the positive and negative electrode detection circuits of the battery; when it is detected that the battery voltage is lower than the undervoltage threshold, the detection circuit sends a low-level signal to the interrupt pin of the control module through the wire.

[0056] Then, the control module calls the trickle charging program through the internal bus. The PWM output pin of the trickle charging program sends a specific duty cycle signal to the drive circuit to perform trickle charging at a current of 5% of the battery capacity.

[0057] During the switching process between trickle charging, constant current charging, and constant voltage charging, the state machine control module within the ASIC is connected to other modules via an internal bus. When switching from trickle charging to constant current charging, the control module gradually increases the duty cycle of the PWM output signal using an internal counter (the counter clock is provided by the chip clock source). This, in turn, causes the charging current to gradually rise to the set constant current value through the driver circuit. When switching from constant current charging to constant voltage charging, the battery voltage reaches the set constant voltage value, detected by the analog-to-digital converter and transmitted to the control module via the internal bus. The control module then switches to voltage closed-loop control, dynamically adjusting the charging current by adjusting the PWM duty cycle using a PID algorithm. The PID algorithm parameters are stored in an on-chip EEPROM, which is connected to the control module via the I2C bus. Throughout this switching process, the control module reads temperature sensor data and voltage change rate in real time via the internal bus. The voltage change rate is calculated from two consecutive analog-to-digital conversions. If the temperature suddenly changes by more than 5°C or the voltage change rate exceeds 0.1V / min, the control module enters a protective standby mode via the power management circuit.

[0058] If the battery voltage remains below the undervoltage threshold after 10 minutes of continuous monitoring by a timer driven by a low-power clock source within the control module, the control module sends a shutdown command to the power management circuit via the internal bus, based on the battery anomaly detection logic preset in the firmware program stored in the internal Flash memory. Upon receiving the command, the power management circuit controls an internal electronic switch to disconnect the power supply line to the trickle charging circuit, stopping the power supply to the trickle charging-related modules. To maintain subsequent monitoring, only the voltage monitoring circuit, powered by an independent low-power power supply, is retained.

[0059] Finally, when the voltage monitoring circuit detects that the battery voltage has recovered to above the undervoltage threshold, the comparator output triggers the control module interrupt. After the control module wakes up, it reinitializes the charging parameters and resumes the normal charging process.

[0060] See also Figure 1 、 Figure 2 and Figure 4 The present invention provides an embodiment of a low-power charging control method in an adaptive standby mode, wherein the positive and negative input terminals of a current detection amplifier within an ASIC are connected to the two ends of a sampling resistor via wires. The sampling resistor is connected in series in a charging circuit, and the output terminal of the current detection amplifier is connected to the external interrupt pin of a control module via a wire. When the voltage difference across the sampling resistor exceeds a short-circuit threshold, the current detection amplifier outputs a high-level signal to the interrupt pin of the control module. The control module sends a control signal to the drive circuit via an internal bus within 20 μs to shut down the charging output drive circuit. The control module starts an internal 1 second timer. If the voltage difference across the sampling resistor exceeds the threshold within 1 second, the control module cuts off power to non-essential circuits via a power management circuit.

[0061] The detection circuits of the negative and positive electrodes of the battery are connected to the input end of the undervoltage protection detection circuit through a wire. When the battery voltage is lower than the undervoltage threshold, the undervoltage protection detection circuit sends a low-level signal to the interrupt pin of the control module through the wire. The control module calls the trickle charging program through the internal bus. The PWM output pin of the trickle charging program sends a duty cycle signal to the drive circuit, and trickle charging is performed at a current of 5% of the battery capacity. If the battery voltage continues to be lower than the undervoltage threshold for 10 minutes, the control module determines that the battery is abnormal and shuts off the power supply of the trickle charging circuit through the power management circuit. When the voltage monitoring circuit powered by the independent low-power power supply detects that the battery voltage has recovered to above the undervoltage threshold, the control module wakes up the battery through the hardware interrupt circuit.

[0062] Furthermore, the temperature sensor in the chip first monitors the temperature in real time, and the output end of the temperature sensor is connected to the ADC input pin of the control module. The temperature sensor converts the temperature signal into an analog voltage signal based on the temperature-voltage characteristics of the semiconductor PN junction, and outputs it to the ADC input pin of the control module. The ADC converts the analog voltage into a digital signal through the successive approximation method for easy reading by the control module; when the temperature value read by the control module exceeds the preset threshold, a signal is sent to the power management circuit and the heat dissipation control circuit through the internal bus.

[0063] Since chip power consumption is approximately proportional to frequency, frequency reduction can significantly reduce dynamic power consumption and heat generation. Therefore, the power management circuit adjusts the clock generator output frequency, reducing the operating frequency of all internal chip modules to 1 / 5 of the normal frequency. The heat dissipation control circuit drives the transistor amplifier circuit to increase the conductivity between the chip's heat sink pins and the PCB heat dissipation layer. The PCB heat dissipation layer is typically a large area of ​​copper foil. By increasing the conductivity, the heat inside the chip is transferred to the copper foil more quickly, and then dissipated through air convection.

[0064] Then, if the temperature continues to rise and exceeds the critical value, the control module cuts off the power supply of the charging output circuit through the switch tube in the power management circuit and enters the overheat protection standby mode.

[0065] Finally, when the temperature sensor detects that the temperature has dropped to a safe range, the control module triggers an interrupt wake-up through the temperature sensor output change, reinitializes the heat dissipation control and charging parameters, and resumes charging if the temperature stabilizes.

[0066] See also Figure 1 、 Figure 3 and Figure 4 The present invention provides an embodiment of a low-power charging control method in an adaptive standby mode, wherein the output end of the on-chip temperature sensor is connected to the ADC input pin of the control module via a wire, the control pin of the clock generator is connected to the control module, the input end of the heat dissipation control circuit is connected to the control module, and the output end of the heat dissipation control circuit is connected to the chip heat dissipation pin drive circuit via a wire; when the temperature value read by the control module exceeds a preset threshold, a signal is sent to the power management circuit and the heat dissipation control circuit via an internal bus, and the power management circuit reduces the module operating frequency by adjusting the output frequency of the clock generator;

[0067] The interrupt pin of the control module is connected to the output end of the VCC overvoltage protection detection circuit, and the input end of the VCC overvoltage protection detection circuit is connected to the VCC power pin of the chip through a wire. When it is detected that the VCC voltage exceeds the preset overvoltage value, the detection circuit sends a high-level signal to the interrupt pin of the control module through the wire. The control module cuts off the MOSFET switch of the charging input circuit through the driving circuit, and the control module outputs an alarm signal through another GPIO pin; when the detection circuit continuously monitors and sends a low-level signal to the interrupt pin of the control module, indicating that the VCC voltage has returned to the normal range, the control module timer is delayed by 500ms, and the control module wakes up through the interrupt to re-detect the input voltage and resume charging;

[0068] Furthermore, the input of the VCC overvoltage protection detection circuit is connected to the chip's VCC power pin, and the output is connected to the control module's interrupt pin. The chip's hardware interrupt circuit uses an independent low-power clock source, the output of which is connected via a wire to the interrupt circuit's clock input pin, providing stable clock support for interrupt signal processing. The calibration module consists of a high-precision reference voltage source, a calibration algorithm circuit, and a calibration parameter register. The high-precision reference voltage source outputs a 2.5V signal to the detection circuit input. The calibration algorithm circuit compares the detection circuit output with the reference signal, calculates the overvoltage detection threshold compensation coefficient, and stores it in the calibration parameter register. When the VCC voltage is detected to exceed the preset overvoltage value, the detection circuit sends a high-level signal to the control module's interrupt pin.

[0069] Then, the control module cuts off the MOSFET switch of the charging input circuit through the driving circuit and outputs a high-level alarm signal through another GPIO pin. At this time, the system is in a protection state.

[0070] Then, when the VCC voltage returns to the normal range, the detection circuit sends a low-level signal to the interrupt pin of the control module. The interrupt trigger condition is written into the register configuration by the control module. For the charging access signal, a 20ms de-bounce filter is set through the digital filter in the interrupt circuit. The digital filter clock is provided by the 32kHz crystal oscillator.

[0071] Finally, after a delay confirming voltage stability, the control module wakes up via an interrupt. It first reads the interrupt flag register via the internal bus, determines the interrupt type, and then calls the corresponding initialization routine to resume the charging process. This initialization routine involves reading charging parameters from the on-chip Flash memory; connecting the Flash memory's data, address, and control lines to the control module; and after reading the parameters, rechecking the input voltage. If the voltage is normal, the control module initializes the charging input circuit and resumes the charging process. If it is still abnormal, it remains in standby mode and continues monitoring.

[0072] Working Principle: First, the detection circuit integrated in the chip's ASIC collects battery charging voltage, current, and temperature parameters in real time. A built-in calibration module ensures that the charging voltage detection error accuracy is within 1%. The wide voltage adaptation circuit processes the input power and combines preset thresholds and temperature to determine the charging stages such as trickle current, constant current, constant voltage, and full charge shutdown.

[0073] Then, the control module adjusts the module status through the power management circuit according to the charging stage and abnormal signals; dynamically switches the charging mode during normal charging, and cuts off the power supply to non-essential modules during standby, so that the static current is ≤5μA; if an abnormality is encountered, the protection standby mode is triggered, further cutting off the power supply to non-essential circuits to reduce power consumption.

[0074] Finally, in standby or protection mode, the hardware interrupt circuit continuously monitors specific signals; when the wake-up conditions are met, the hardware interrupt circuit wakes up the chip in a short time. After the control module is awakened, it reads the interrupt flag register to determine the interrupt type, reads the charging parameters from the Flash memory in the chip, initializes the relevant modules, and resumes the normal charging process or enters the corresponding processing logic.

[0075] It will be apparent 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 invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

Claims

1. A low-power charging control method in an adaptive standby mode, characterized by: The following steps are involved: S1. Utilize the detection circuit integrated in the chip's ASIC to collect battery charging voltage, current, and temperature parameters in real time. The detection circuit uses a built-in calibration module to control the charging voltage detection error accuracy to within 1%. S2, processes the input power through a 4.5-6V wide voltage adapter circuit, and determines the trickle current, constant current, constant voltage and full charge shutdown stages based on the preset threshold and temperature; S3. The control module adjusts the module status through the power management circuit, cuts off the power supply to non-essential modules in standby mode to make the static current ≤ 5μA, and triggers the protection standby mode according to the abnormal signal; S4. In standby mode, the output is cut off. The hardware interrupt circuit in the chip detects that the charging current is lower than 1% of the battery capacity. When the wake-up condition is met, the hardware interrupt circuit wakes up the chip in no more than 100μs to resume charging.

2. The low-power charging control method in an adaptive standby mode according to claim 1, characterized in that: The ASIC integrates the voltage comparator, analog-to-digital converter, and control logic unit required for charging control on the same chip substrate through layout and routing. The input and output pins are distributed around the chip, and the voltage comparator, analog-to-digital converter, and control logic unit are connected by metal wires. The input pin of the voltage comparator is directly connected to the external detection circuit, and the output pin is connected to the control module through an internal wire. The wire connects the input power supply to the chip power pin, the positive and negative poles of the battery to the chip charging input pin, the LED to the status pin and a series resistor to ground.

3. The low-power charging control method in an adaptive standby mode according to claim 1, characterized in that: The wide voltage adaptation circuit is processed by a multi-stage voltage stabilization circuit in the chip. The multi-stage voltage stabilization circuit includes a front-end anti-reverse connection diode circuit, an LC filter circuit, and a DC-DC voltage stabilization circuit. The anode of the anti-reverse connection diode circuit is connected to the positive pin of the input power socket through a PCB wire, and the cathode is connected to one end of the inductor of the LC filter circuit through a wire; the other end of the LC filter circuit is connected to one end of the ceramic capacitor and the input pin of the DC-DC voltage stabilization circuit through a wire, and the other end of the ceramic capacitor is grounded through a wire. The DC-DC voltage regulator circuit adopts a synchronous buck topology. The gate of the internal switch tube is connected to the output pin of the PWM control chip through a wire. The power pin of the PWM control chip is connected to the cathode of the anti-reverse diode through a wire. The feedback pin of the PWM control chip is connected to the voltage divider circuit of the power input pin of the charging module through a wire. The PWM mode dynamically adjusts the duty cycle according to the input voltage and load changes.

4. The low-power charging control method in an adaptive standby mode according to claim 1, characterized in that: In the charging voltage detection, the analog input pin of the 24-bit Σ-Δ analog-to-digital converter in the ASIC is connected to the output of the programmable gain amplifier via a wire, the input of the programmable gain amplifier is connected to the battery voltage detection circuit via a wire, and the gain control pin of the programmable gain amplifier is connected to the GPIO pin of the control module via a wire. The control module outputs different level combinations to the GPIO pin according to the battery voltage range, and controls the amplification factor of the programmable gain amplifier through an internal decoding circuit; The reference voltage pin of the analog-to-digital converter is connected to the output end of the bandgap reference source in the chip through a wire, and the digital output pin of the analog-to-digital converter is connected to the data input interface of the control module through an internal bus; combined with the calibration data of the bandgap reference source and the analog-to-digital converter at different temperatures before leaving the factory, the detection results are adjusted through a digital calibration algorithm.

5. The low-power charging control method in an adaptive standby mode according to claim 1, characterized in that: During the fully charged shutdown phase, the PWM output pin of the control module is connected to the input of the drive circuit via a wire, and the output of the drive circuit is connected to the gate of the power MOSFET of the charging output circuit via a wire; the source of the MOSFET is connected to the positive electrode of the charging power supply via a wire, and the drain is connected to the positive electrode of the battery via a wire; In the later stage of constant-voltage charging, the control module continuously reads the current data output by the analog-to-digital converter through the internal bus. When the current drops below 1% of the battery capacity and lasts for 10 minutes, the control module sends a low-level signal to the drive circuit through the PWM output pin. The drive circuit outputs a low level and the MOSFET is turned off. The control module outputs a signal to the LED drive circuit through another GPIO pin to control the LED to turn off and flash slowly.

6. The low-power charging control method in an adaptive standby mode according to claim 1, characterized in that: The source of the PMOS switch tube of the power management circuit is connected to the chip power input pin via a wire, and the drain is connected to the power input pins of non-essential modules via wires. In standby mode, the control module sends a low-level signal to the PMOS gate via an internal drive circuit, and the power pin of the analog-to-digital converter is connected to a power switch that can be turned off via a wire. The power pin of the voltage comparator is connected to the output of the low-power LDO regulator in the chip through a wire. The LDO input is connected to the chip power supply and the output is connected to the power pin of the voltage comparator and the control module circuit through a wire. When the logic unit inside the control module enters the sleep state in standby mode, the power pins of the interrupt processing unit and the register are connected to the output of the LDO regulator through an independent low-power line.

7. The low-power charging control method in an adaptive standby mode according to claim 1, characterized in that: The positive and negative input terminals of the current detection amplifier in the ASIC are connected to the two ends of the sampling resistor through wires. The sampling resistor is connected in series in the charging circuit. The output terminal of the current detection amplifier is connected to the external interrupt pin of the control module through a wire. When the voltage difference across the sampling resistor exceeds the short-circuit threshold, the current detection amplifier outputs a high-level signal to the interrupt pin of the control module. The control module sends a control signal to the drive circuit through the internal bus within 20μs to turn off the charging output drive circuit. The control module starts the internal 1s timer. If the voltage difference across the sampling resistor is higher than the threshold within 1s, the control module cuts off the power supply to non-essential circuits through the power management circuit.

8. The low-power charging control method in an adaptive standby mode according to claim 1, characterized in that: The detection circuits of the negative and positive electrodes of the battery are connected to the input ends of the undervoltage protection detection circuit through wires. When the battery voltage is lower than the undervoltage threshold, the undervoltage protection detection circuit sends a low-level signal to the interrupt pin of the control module through the wire. The control module calls the trickle charging program through the internal bus. The PWM output pin of the trickle charging program sends a duty cycle signal to the drive circuit, and trickle charging is performed with a current of 5% of the battery capacity. If the battery voltage continues to be lower than the undervoltage threshold for 10 minutes, the control module determines that the battery is abnormal and turns off the power supply of the trickle charging circuit through the power management circuit. When the voltage monitoring circuit powered by an independent low-power power supply detects that the battery voltage has recovered to above the undervoltage threshold, the control module wakes up the battery through the hardware interrupt circuit.

9. The low-power charging control method in an adaptive standby mode according to claim 1, characterized in that: The output end of the temperature sensor in the chip is connected to the ADC input pin of the control module through a wire, the control pin of the clock generator is connected to the control module, the input end of the heat dissipation control circuit is connected to the control module, and the output end of the heat dissipation control circuit is connected to the chip heat dissipation pin drive circuit through a wire; When the temperature value read by the control module exceeds the preset threshold, a signal is sent to the power management circuit and the heat dissipation control circuit through the internal bus. The power management circuit reduces the module operating frequency by adjusting the output frequency of the clock generator.

10. The low-power charging control method in an adaptive standby mode according to claim 1, characterized in that: The interrupt pin of the control module is connected to the output end of the VCC overvoltage protection detection circuit, and the input end of the VCC overvoltage protection detection circuit is connected to the VCC power pin of the chip through a wire. When it is detected that the VCC voltage exceeds the preset overvoltage value, the detection circuit sends a high-level signal to the interrupt pin of the control module through the wire, and the control module cuts off the MOSFET switch of the charging input circuit through the driving circuit, and the control module outputs an alarm signal through another GPIO pin; when the detection circuit continuously monitors and sends a low-level signal to the interrupt pin of the control module to indicate that the VCC voltage has returned to the normal range, the control module timer is delayed by 500ms, and the control module wakes up through the interrupt to re-detect the input voltage and resume charging.

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