Intelligent control charging circuit

Abstract

The invention relates to the technical field of charging circuits, in particular to an intelligent control charging circuit which comprises a charging detection circuit which is composed of a single lithium ion battery charging management IC and a peripheral circuit of the single lithium ion battery charging management IC and used for monitoring and managing current and voltage in the charging process; and the charging circuit receives an input signal from the J1 port, processes the input signal through a transient voltage suppressor, an inductor, a diode, an input capacitor, a metal oxide semiconductor field effect transistor and an output capacitor, and supplies power to a system and charges a battery. The circuit of the invention can automatically adjust charging parameters, ensure charging efficiency, and improve charging safety and effectiveness through intelligent control. Key parameters of the battery are monitored in real time, dangers such as overcharging and overheating are prevented, and safe and reliable charging of electronic equipment is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of charging circuits, and in particular to an intelligent control charging circuit. Background Art

[0002] With the rapid development of science and technology, intelligent technology has been widely infiltrated into many fields such as military, medical, agriculture, electricity, security, etc., and the requirements for product accuracy and performance are getting higher and higher. In this context, this paper proposes a design scheme for an intelligent control charging circuit, which aims to significantly improve the charging efficiency of electronic devices while ensuring the effectiveness and safety of the charging process.

[0003] For those electronic devices that could only be charged slowly and inefficiently by replacing batteries in the past, the core innovation of this design is to use advanced power management chips to achieve pass-through mode, thereby greatly improving charging efficiency. Through this design, the fast charging function of the battery can be realized. Specifically, when the system detects the presence of a battery, the charging process will automatically start and go through three stages of pre-charging, constant current and constant voltage in sequence. During this process, the system has multiple protection mechanisms, including battery overvoltage protection, short circuit detection, thermal shutdown, safety timer expiration, and input voltage protection. These protection measures can ensure the safety of the battery during the charging process and avoid damage caused by overcharging, short circuit or other potential risks, thereby providing users with an efficient and safe charging solution. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention discloses an intelligent control charging circuit for solving the above problems.

[0005] The present invention is achieved through the following technical solutions:

[0006] The present invention provides an intelligent control charging circuit, comprising

[0007] The charging detection circuit, which consists of a single-chip lithium-ion battery charging management IC and its peripheral circuits, is used to monitor and manage the current and voltage during the charging process;

[0008] The charging circuit receives the input signal from the J1 port and processes it through the transient voltage suppressor, inductor, diode, input capacitor, metal oxide semiconductor field effect transistor and output capacitor to power the system and charge the battery.

[0009] Furthermore, in the charging detection circuit, the ACN pin plays a vital role. It is mainly used to detect the negative input part of the input current. At the same time, the ACP pin is responsible for detecting the positive input part of the input current. These two pins work together to act on the entire circuit system. Through the cooperation of the ACN and ACP pins, the high-frequency noise mixed in the input current signal can be effectively suppressed and eliminated, thereby ensuring the stability and accuracy of the circuit. This design not only improves the anti-interference ability of the circuit, but also ensures the accuracy of the detection results, providing a strong guarantee for the efficient operation of the entire charging system.

[0010] Furthermore, in the charging detection circuit, a bootstrap capacitor is connected between the PH port and the BTST port. The function of this bootstrap capacitor is to form a bootstrap circuit in the circuit to ensure that the circuit can work normally. At the same time, a bootstrap Schottky diode is connected between the REGN port and the BTST port. The function of this bootstrap Schottky diode is to further ensure the stability and reliability of the bootstrap circuit and prevent abnormal conditions in the circuit. Through the connection of these two key components, the entire charging detection circuit is able to form a complete bootstrap circuit, thereby ensuring that the circuit can operate stably during operation and improving the performance and reliability of the circuit.

[0011] Furthermore, the main function of the bootstrap circuit is to provide the required positive power supply for the PWM high-side driver. This bootstrap circuit can create a floating positive power supply higher than the input voltage in the circuit through a combination of a capacitor and a diode. Specifically, when the PWM signal is at a low level, the capacitor will charge to the input voltage; and when the PWM signal is at a high level, the capacitor will provide additional voltage to the high-side driver through the diode, thereby ensuring that the driver can work normally at a level higher than the input voltage. This bootstrap technology is widely used in many electronic systems, especially in situations where high-side switches need to be driven, such as motor drives, power management, and inverters. In this way, the bootstrap circuit effectively solves the power supply problem of the high-side driver and ensures the stable and efficient operation of the entire system.

[0012] Furthermore, in the above-mentioned charging detection circuit, the voltage of the ISET1 pin plays a vital role. It is used to accurately program the adjustment set point of the fast charging current. By adjusting the voltage value of the ISET1 pin, a specific current value can be set to ensure that the current size during the fast charging process meets the predetermined requirements to achieve the purpose of fast charging while avoiding damage to the battery due to excessive current.

[0013] Similarly, the voltage of the ISET2 pin also plays an important role in the charge detection circuit. It is used to program the adjustment set point of the pre-charge current, which means that by adjusting the voltage value of the ISET2 pin, an initial current value can be set for pre-charging when the battery power is low. In addition, the voltage of the ISET2 pin is also used to set the terminal current trigger point, that is, when the battery is close to full charge, a trigger point can be set by the voltage value of the ISET2 pin. When the charging current drops to this trigger point, the charging process will automatically stop or switch to other charging modes to ensure the safety of the battery and extend its service life. In this way, the voltage of the ISET2 pin not only controls the pre-charge current size, but also ensures the safety and reliability of the battery during the charging process.

[0014] Furthermore, in the above charging detection circuit, the LODRV pin plays a vital role. It is the output port of the PWM (pulse width modulation) low-side driver. Through this port, the circuit can accurately control the switching action of the low-side power MOSFET (metal oxide semiconductor field effect transistor). This precise control is essential to ensure the efficient operation and stable output of the circuit.

[0015] In addition, the PH pin also plays an indispensable role in the circuit. It is the negative power connection point of the PWM low-end driver and is responsible for providing the necessary power support for related components. Specifically, the PH pin is connected to the drain of the low-end power MOSFET, the source of the high-end power MOSFET, and the connection point of the output inductor. This connection method ensures that the various key components in the circuit can work together to achieve efficient energy conversion and transmission. Through this design, the circuit can process and distribute electrical energy more stably, ensuring the reliability and performance of the entire system.

[0016] Furthermore, the PG port of the single-chip lithium-ion battery charge management integrated circuit mentioned above will output a low-level signal when its VCC input is valid; conversely, when the VCC input is invalid, the PG port will output a high-level signal. The function of the PG port is to drive a light-emitting diode or communicate with a host processor.

[0017] Furthermore, in the charging detection circuit, the RECG port is used as the positive power output of the PWM low-end driver, connected between the REGN port and the nearest GND pin near the monolithic lithium-ion battery charging management IC, and the voltage is stabilized by the configuration of ceramic capacitors.

[0018] Furthermore, in the charging circuit, when the power supply end is disconnected, the VBAT end supplies power to the system end through the MOS field effect transistor Q5.

[0019] Furthermore, in the charging circuit, automatic detection of the battery status is implemented. When the battery is detected, the charging process is immediately started, and it goes through the pre-charging, constant current charging and constant voltage charging stages in sequence. During this charging process, the circuit has battery overvoltage protection, short circuit detection, thermal shutdown functions, as well as a safety timer and input voltage protection mechanism.

[0020] The beneficial effects of the present invention are:

[0021] The present invention proposes a design scheme of an intelligent control charging circuit, aiming to significantly improve the charging efficiency of various electronic devices. By adopting a monolithic lithium-ion battery charging management IC, the circuit can automatically adjust the charging parameters according to the specific needs of the electronic device and the battery status, thereby ensuring the efficient charging process. In addition, this intelligent control charging circuit can not only improve the effectiveness of charging, but also significantly enhance the safety of the charging process. By real-time monitoring of key parameters such as battery temperature, voltage and current, the circuit can automatically adjust or interrupt charging when necessary to prevent the occurrence of potentially dangerous situations such as overcharging and overheating, thereby ensuring the safety and reliability of electronic devices during the charging process. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 It is a schematic diagram of an intelligent control charging circuit;

[0024] Figure 2 1 is a block diagram of the charging circuit of this embodiment. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are 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 creative work are within the scope of protection of the present invention.

[0026] In one embodiment, referring to Figure 1 As shown, an intelligent control charging circuit is provided, which helps to improve the charging efficiency of electronic devices and enhance the effectiveness and safety of the charging process. The circuit comprises a charging circuit and a matching charging monitoring circuit.

[0027] The power supply circuit of this embodiment starts to input from the J1 port, first passing through a bidirectional transient voltage suppressor (TVS) tube D3 to protect the circuit from voltage spikes. Then, the current passes through the common-mode filter inductor L3, which can effectively suppress common-mode noise and improve the stability of the circuit. After that, the current flows through the Schottky diode D12, which has fast switching characteristics and low forward voltage drop, which helps to improve the efficiency of the circuit. Subsequently, the current enters the input capacitors, which can smooth the input voltage, reduce ripple, and provide a stable voltage source for subsequent circuits.

[0028] In this embodiment, the current passes through two MOS field effect transistors Q4 and Q6, which act as switches in the circuit to control the flow of current. By accurately controlling the switches of the two MOS transistors, the output voltage and current can be accurately adjusted. After passing through the MOS transistor, the current enters the inductor L11, which acts as an energy storage and filtering device to further reduce the fluctuation of the output voltage.

[0029] In this embodiment, after being processed by these components, the current finally reaches the output capacitors, which further smooth the output voltage to ensure that the system end obtains a stable power supply. At the same time, this power supply circuit is also responsible for charging the battery to ensure that the battery can provide power when needed.

[0030] In this embodiment, when the power supply terminal J1 is disconnected, that is, the external power supply is no longer powered, the circuit automatically switches to the battery power supply mode. At this time, the VBAT terminal supplies power to the system terminal through another MOS field effect transistor Q5. The MOS tube Q5 acts as a switch here to ensure that the battery can quickly take over the power supply task when the external power supply is disconnected, ensuring the continuous operation of the system and avoiding system failure or data loss due to power interruption.

[0031] The charging monitoring circuit of this embodiment is composed of the U5 chip (monolithic lithium-ion battery charging management IC) and its peripheral circuits. The main function of this circuit is to connect and monitor the charging end of the charging circuit. In this charging monitoring circuit, the ACN pin is responsible for detecting the negative input signal of the input current, while the ACP pin is responsible for detecting the positive input signal of the input current. The function of these two pins is to suppress the high-frequency noise that may exist in the input current signal, thereby ensuring the accuracy and stability of the signal.

[0032] The BTST pin in the charging monitoring circuit of this embodiment is a positive power supply interface of a PWM high-end driver. A 0.1UF bootstrap capacitor is connected between the PH pin and the BTST pin to ensure the normal operation of the circuit. At the same time, a bootstrap Schottky diode is also connected between the REGN pin and the BTST pin to further ensure the stability and reliability of the circuit.

[0033] The ISET1 pin of the charging monitoring circuit of this embodiment is used to set the adjustment point of the fast charging current. By adjusting the voltage value of this pin, the current size of the fast charging can be accurately controlled. The ISET2 pin is used to set the adjustment point of the pre-charge current and the trigger point of the end current. By adjusting the voltage value of this pin, the parameters of the pre-charge and end current can be flexibly controlled. The LODRV pin of the charging monitoring circuit is the output end of the PWM low-end driver, which is responsible for outputting the corresponding drive signal. The PG pin is an open-drain power good status output end. When the U5 chip has a valid VCC, the PG pin outputs a low-level signal, indicating that the power supply status is good; conversely, when the VCC of the U5 chip is invalid, the PG pin outputs a high-level signal, indicating that the power supply status is abnormal. The PG pin can be used to drive an LED indicator or communicate with a host processor to achieve real-time monitoring of the power supply status.

[0034] The PH pin of the charging monitoring circuit of this embodiment is the negative power supply interface of the PWM low-end driver, which is connected to the phase switching node, that is, the drain of the low-end power MOSFET, the source of the high-end power MOSFET and the connection point of the output inductor. Such a design ensures the stability and reliability of the circuit under different working conditions.

[0035] The RECG pin of the charging monitoring circuit of this embodiment is the positive 6V power output terminal of the PWM low-end driver. A 1UF ceramic capacitor is connected between the REGN pin and the GND pin near the U5 chip to ensure the stable output of the power supply. In addition, a small signal Schottky diode is connected from the REGN pin to the BTST pin to provide a bootstrap voltage for the low-end driver and the high-end driver, further enhancing the driving capability and stability of the circuit.

[0036] In one embodiment, the charging detection circuit is mainly composed of the integrated circuit U5 and its peripheral circuits, and its main function is to monitor and manage the current and voltage during the charging process to ensure the safety and efficiency of the charging process. The following are several key principles and components of the circuit:

[0037] 1. Input current detection:

[0038] The ACN pin is used to detect the negative input of the input current, while the ACP pin is used to detect the positive input of the input current. These two pins work together to suppress the high-frequency noise in the input current signal and improve the accuracy of detection.

[0039] 2. Bootstrap circuit:

[0040] Connect a 0.1uF bootstrap capacitor between PH and BTST, and a bootstrap Schottky diode between REGN and BTST, these components form a bootstrap circuit. The bootstrap circuit provides a positive power supply for the PWM high-side driver to ensure that the driver can work normally during switching operation.

[0041] 3. Current Regulation Set Point Programming:

[0042] The voltage at the ISET1 pin is used to program the fast charge current regulation set point.

[0043] The voltage at the ISET2 pin is used to program the precharge current regulation set point and the endpoint current trigger point.

[0044] 4.PWM driver output:

[0045] The LODRV pin is the output of the PWM low-side driver, which is used to control the switching of the low-side power MOSFET.

[0046] The PH pin is the negative power supply for the PWM low-side driver and is usually connected to the phase switching node, which is the connection point of the drain of the low-side power MOSFET, the source of the high-side power MOSFET and the output inductor.

[0047] 5. Power good status output:

[0048] The PG pin is an open-drain power-good status output. When U5 has a valid VCC, PG outputs a low level; when U5's VCC is invalid, PG outputs a high level. PG can be used to drive an LED or communicate with a host processor.

[0049] 6. Positive 6V power output:

[0050] The RECG pin is the positive 6V power supply output for the PWM low-side driver. A 1uF ceramic capacitor is connected between REGN and the GND pin near U5 to stabilize the voltage. In addition, REGN is connected to BTST through a small signal Schottky diode to provide bootstrap voltage for the low-side driver and high-side driver.

[0051] In one embodiment, referring to Figure 2 As shown, the charging circuit principle is summarized as follows:

[0052] 1. Input protection: After the power is input from the J1 terminal, it first passes through the bidirectional TVS tube D3, whose main function is to protect the circuit from damage by voltage spikes and ensure the stability and safety of the circuit.

[0053] 2. Filtering: Then, the power supply passes through the common-mode filter inductor L3, which can suppress the common-mode interference on the power line and improve the anti-interference ability of the circuit.

[0054] 3. Rectification: The filtered power is then rectified by Schottky diode D12 to ensure the correct direction of the power.

[0055] 4. Energy storage and filtering: The power then enters the input capacitor for energy storage and filtering to smooth out power fluctuations and provide a stable power supply.

[0056] 5. Switch control: MOS field effect transistors Q4 and Q6 act as switch elements to control the on and off of the power supply and the size of the current.

[0057] 6. Energy storage and output: The power supply stores energy through the inductor L11, and after further filtering through the output capacitor, it directly supplies power to the system end on the one hand, and charges the battery on the other hand.

[0058] 7. Power-off protection: When the external power supply is disconnected, the system continues to power the system through the power stored in the VBAT terminal through the MOS field effect transistor Q5, ensuring that the system will not shut down immediately due to power failure.

[0059] By adopting the pass-through mode of the power management chip, the present invention can significantly improve the charging efficiency, thereby realizing the fast charging function of the battery. During the charging process, the system can automatically detect whether the battery exists. Once the battery is detected, the charging process will be carried out according to the preset steps, specifically including the pre-charging stage, the constant current charging stage and the constant voltage charging stage. In these stages, the present invention also has a number of protection functions to ensure the safety of the battery. These protection functions include battery overvoltage protection, short circuit detection, thermal shutdown protection, safety timer expiration protection and input voltage protection. Through these comprehensive protection measures, the present invention can effectively prevent battery damage or other safety problems caused by improper charging, thereby greatly improving the safety performance of the battery.

[0060] In summary, the present invention proposes a design scheme for an intelligent control charging circuit, which aims to significantly improve the charging efficiency of various electronic devices. By adopting a monolithic lithium-ion battery charging management IC, the circuit can automatically adjust the charging parameters according to the specific needs of the electronic device and the battery status, thereby ensuring the efficient charging process. In addition, this intelligent control charging circuit can not only improve the effectiveness of charging, but also significantly enhance the safety of the charging process. By real-time monitoring of key parameters such as battery temperature, voltage and current, the circuit can automatically adjust or interrupt charging when necessary to prevent the occurrence of potentially dangerous situations such as overcharging and overheating, thereby ensuring the safety and reliability of electronic devices during the charging process.

[0061] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An intelligent control charging circuit, characterized in that: include The charging detection circuit, which consists of a single-chip lithium-ion battery charging management IC and its peripheral circuits, is used to monitor and manage the current and voltage during the charging process; The charging circuit receives the input signal from the J1 port and processes it through the transient voltage suppressor, inductor, diode, input capacitor, metal oxide semiconductor field effect transistor and output capacitor to power the system and charge the battery.

2. The intelligent control charging circuit according to claim 1, characterized in that: In the charging detection circuit, the ACN pin is used to detect the negative input of the input current, and the ACP pin is used to detect the positive input of the input current. The ACN pin and the ACP pin work together to suppress high-frequency noise in the input current signal.

3. The intelligent control charging circuit according to claim 1, characterized in that: A bootstrap capacitor is connected between PH and BTST of the charging detection circuit, and a bootstrap Schottky diode is connected between REGN and BTST to form a bootstrap circuit.

4. The intelligent control charging circuit according to claim 3, characterized in that: The bootstrap circuit provides a positive power supply for the PWM high-side driver.

5. The intelligent control charging circuit according to claim 1, characterized in that: In the charging detection circuit, the voltage of the ISET1 pin is used to program the regulation set point of the fast charging current; The voltage at the ISET2 pin is used to program the precharge current regulation set point and the endpoint current trigger point.

6. The intelligent control charging circuit according to claim 5, characterized in that: In the charging detection circuit, the LODRV pin is the output of the PWM low-end driver, which is used to control the switch of the low-end power MOSFET; The PH pin is the negative power supply of the PWM low-side driver, connecting the drain of the low-side power MOSFET, the source of the high-side power MOSFET and the connection point of the output inductor.

7. The intelligent control charging circuit according to claim 1, characterized in that: When the single-chip lithium-ion battery charging management IC has a valid VCC, PG outputs a low level; when the VCC of the single-chip lithium-ion battery charging management IC is invalid, PG outputs a high level, and PG is used to drive an LED or communicate with a host processor.

8. The intelligent control charging circuit according to claim 1, characterized in that: In the charging detection circuit, the RECG pin is the positive power supply output of the PWM low-side driver, and a ceramic capacitor is connected between the REGN and the nearest GND pin around the monolithic lithium-ion battery charging management IC to stabilize the voltage.

9. The intelligent control charging circuit according to claim 1, characterized in that: In the charging circuit, when the power supply end is disconnected, the VBAT end supplies power to the system end through the MOS field effect transistor Q5.

10. The intelligent control charging circuit according to claim 1, characterized in that: In the charging circuit, automatic detection of the battery status is achieved. When the battery is detected, the charging process is immediately started, and it goes through the pre-charging, constant current charging and constant voltage charging stages in sequence. During this charging process, the circuit has battery overvoltage protection, short circuit detection, thermal shutdown functions, as well as a safety timer and input voltage protection mechanism.

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