Disclosure of Invention
In order to solve the problems existing in the existing quick-charging scheme of consumer electronic products, the invention provides a quick-charging device, a charging module and consumer electronic products.
According to a first aspect of the present invention, there is provided a quick charge charging device for connecting a dc power source to a charging module of a consumer electronic product; the charging device comprises a charging module, a logic control module, a voltage conversion module and a first voltage division unit, wherein the charging module comprises a power management chip and a load switch unit which are integrated with a linear charging unit; wherein:
the first voltage dividing unit is coupled to the output end of the direct current power supply and is used for dividing the power supply voltage output by the direct current power supply to obtain a first voltage and a second voltage and outputting the first voltage and the second voltage; wherein the first voltage is greater than the second voltage;
the enabling end and the voltage input end of the voltage conversion module are respectively coupled to the first output end of the first voltage division unit and the output end of the direct current power supply; the voltage conversion module is used for judging whether the value of the power supply voltage exceeds a starting voltage value according to the input first voltage; if the voltage exceeds the first charging voltage, the voltage conversion module is also used for converting the power supply voltage into a first charging voltage and outputting the first charging voltage; wherein the first charging voltage is lower than an overvoltage threshold value of the charging module in a charging process;
The input end and the output end of the intelligent switch unit are respectively coupled to the voltage output end of the voltage conversion module and the charging input end of the charging module; the intelligent switch unit is used for controlling the on-off of a branch circuit between the direct-current power supply and the charging module, and is also used for maintaining a first current flowing through the intelligent switch unit at a target constant value; the target constant current value is used for representing the range of the constant current value output to the charging module in the quick charging process;
the first pin and the second pin of the logic control module are respectively coupled to the current detection end of the intelligent switch unit and the second output end of the first voltage division unit; the logic control module is used for:
detecting a value of the first current through the first pin;
detecting a value of the power supply voltage according to the input second voltage; and
according to the descending degree of the value of the power supply voltage in the charging process, the target constant current value is regulated; if the degree of the decrease of the value of the power supply voltage exceeds a first threshold value, the logic control module decreases the upper limit and the lower limit of the target constant value; if the degree of the decrease in the value of the power supply voltage is lower than the first threshold value, the logic control module maintains or increases the upper and lower limits of the target constant current value.
Optionally, a power pin of the logic control module is coupled to an output end of the voltage conversion module, a fourth pin of the logic control module is coupled to a charging input end of the charging module, and the logic control module is further configured to:
dividing the first charging voltage through a built-in voltage dividing circuit so as to supply power to the logic control module; and
analog-to-digital conversion is carried out on the divided voltage of the first charging voltage so as to detect the first charging voltage; detecting the actual battery voltage of the battery assembly in the quick charge process through a charging input end of the charging module, and setting a target value of the first charging voltage according to the actual battery voltage; wherein the target value is larger than the actual battery voltage, and the difference value between the target value and the actual battery voltage is at least the product of the set target constant current value and the first on-resistance; and
comparing the detected first charging voltage with the target value; and if the difference exists, correcting the first charging voltage according to the difference after the difference is obtained.
Optionally, the device further comprises a voltage regulating single wire; the third pin of the logic control module is coupled to the control end of the voltage conversion module through the voltage regulating single wire; and outputting a voltage regulating signal to a control end of the voltage conversion module according to the difference value; the voltage conversion module is used for correcting the self-output first charging voltage according to the voltage regulating signal.
Optionally, the filter further comprises a second voltage division unit, a filter unit and a first resistor; the input end and the output end of the second voltage division unit are respectively coupled to the output end of the voltage conversion module and the sampling end of the voltage conversion module, and the first end of the second voltage division unit is grounded; the second voltage dividing unit is used for performing third voltage division on the first charging voltage to obtain a third voltage and outputting the third voltage to a sampling end of the voltage conversion module; the input end and the output end of the filtering unit are respectively coupled to the third pin of the logic control module and the first end of the first resistor, and the first end of the filtering unit is grounded; the second end of the first resistor is coupled to the sampling end of the voltage conversion module;
the third pin of the logic control module is used for outputting PWM signals corresponding to the duty ratio according to the difference value; the filtering unit is used for filtering the PWM signal to obtain average voltage and outputting the average voltage; the first resistor is used for matching and setting the output impedance of the filtering unit so that the average voltage is added to the sampling end of the voltage conversion module; the voltage conversion module is used for correcting the self-output first charging voltage according to the sum of the average voltage and the third voltage.
Optionally, the filtering unit includes a filtering resistor and a filtering capacitor; the first end of the filter resistor is coupled to the third pin of the logic control module, and the second end of the filter resistor is coupled to the first end of the filter capacitor and serves as the output end of the filter unit; the second end of the filter capacitor is grounded.
Optionally, the second voltage dividing unit includes a fourth voltage dividing resistor and a fifth voltage dividing resistor; the first end of the fourth voltage dividing resistor is coupled to the output end of the voltage conversion module, and the second end of the fourth voltage dividing resistor is coupled to the first end of the fifth voltage dividing resistor and serves as the output end of the second voltage dividing unit; the second end of the fifth voltage dividing resistor is grounded.
Optionally, the intelligent switch unit comprises a main channel switch subunit and a constant current regulating subunit; the first end and the second end of the main channel switch subunit are respectively coupled to the voltage output end of the voltage conversion module and the charging input end of the charging module, and the main channel switch subunit is used for controlling the on-off of a branch circuit between the direct current power supply and the charging module according to the on-off of the main channel switch subunit; the first end, the second end, the input end and the output end of the constant current regulating subunit are respectively coupled to the first end and the second end of the main channel switch subunit, the current detection end of the intelligent switch unit and the control end of the main channel switch subunit; the constant current regulating subunit is used for detecting the first current and regulating the first current by controlling the conduction degree of the main channel switch subunit under the control of the logic control module.
Optionally, the main channel switch unit at least includes an NMOS tube or a PMOS tube.
Optionally, the logic control module is further configured to send a handshake signal to the charging module through the fourth pin, so as to control the charging module to switch from the first state to the second state; the first state is used for representing that the charging module is in a normal charging state, and the second state is used for representing that the charging module is in a state of digital interaction authentication with the logic control module; if the digital interaction authentication is passed, the charging module is characterized to accept quick charging;
the logic control module is further configured to send a first signal to the charging module to control the charging module to switch from the second state to the first state.
Optionally, the logic control module is further configured to:
before sending the handshake signal, turning off the intelligent switching unit by sending a second signal to the intelligent switching unit; and
and before the first signal is sent, sending a third signal to the intelligent switch unit so as to conduct the intelligent switch unit.
Optionally, the first voltage dividing unit includes a first voltage dividing resistor, a second voltage dividing resistor, and a third voltage dividing resistor; the first end and the second end of the first voltage dividing resistor are respectively coupled to the output end of the direct current power supply and the first end of the second voltage dividing resistor, and the second end of the first voltage dividing resistor is used as the first output end of the first voltage dividing unit; the second end of the second voltage dividing resistor is coupled to the first end of the third voltage dividing resistor and serves as a second output end of the first voltage dividing unit; the second end of the third voltage dividing resistor is grounded.
According to a second aspect of the present invention, there is provided a charging module, matching with the quick-charging device provided in the first aspect and the alternative aspects of the present invention, for charging a battery assembly in the consumer electronic product, the charging module including a power management chip integrated with a linear charging unit and a load switch unit;
the input end of the power management chip is used as a charging input end of the charging module; the output end of the power management chip is coupled to the positive electrode of the battery assembly, and the power management chip is also coupled to the control end of the load switch unit; the power management chip is used for:
converting the input first charging voltage into a second charging voltage and outputting the second charging voltage to the positive electrode of the battery assembly so as to perform first charging on the battery assembly; and
according to the input handshake signals, carrying out digital interactive authentication with the logic control module; if the authentication is passed, the receiving is indicated to enter a quick charge state; and when the voltage of the battery assembly is greater than a second threshold value, controlling the load switch unit to be conducted;
the input end and the output end of the load switch unit are respectively coupled to the input end of the power management chip and the anode of the battery assembly; and the load switch unit is used for directly pouring the first current input by the charging input end into the positive electrode of the battery assembly after being controlled to be conducted so as to rapidly charge the battery assembly.
The invention provides a quick charging device and a charging module; the function of the switch charging chip in the existing quick charging scheme is split, the voltage conversion module corresponding to the quick charging function, the intelligent switch unit and the logic control module are integrated in the charging device, and the charging module of the consumer electronic product only reserves the traditional power management chip and the load switch, so that the problems of occupation of circuit area, overhigh circuit cost and heating of an internal main board of the consumer electronic product caused by the switch charging chip are solved. The voltage conversion module is used for converting the power supply voltage of the direct-current power supply into a first charging voltage so as to ensure that the charging device can still normally charge the consumer electronic product when the power supply voltage exceeds an overvoltage critical value of the charging module in the charging process; the logic control module is used for detecting the value of the power supply voltage and the value of the first current, and adaptively adjusting the range of the constant current value output to the charging module in the quick charging process according to the descending degree of the value of the power supply voltage in the charging process so as to furthest improve the charging efficiency on the basis of ensuring the charging stability.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention. The terms "first," "second," "third," "fourth" and the like in the description and in the claims and in the above drawings, if any, are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that the embodiments of the invention described herein may be implemented in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.
Referring to fig. 1, a first embodiment of the present invention provides a quick charging device for connecting a dc power source and a charging module of a consumer electronic product; the charging module comprises a power management chip and a load switch unit which are integrated with a linear charging unit, so as to charge a battery assembly in the consumer electronic product, and the charging device is internally provided with an intelligent switch unit 10, a logic control module 30, a voltage conversion module 20 and a first voltage division unit 40; wherein:
the first voltage dividing unit 40 is coupled to the output end of the dc power supply, and is configured to divide the power supply voltage VBUS output by the dc power supply to obtain a first voltage and a second voltage, and output the first voltage and the second voltage; wherein the first voltage is greater than the second voltage;
the enable terminal and the voltage input terminal of the voltage conversion module 20 are coupled to the first output terminal of the first voltage dividing unit 40 and the output terminal of the dc power supply, respectively; the voltage conversion module 20 is configured to determine whether the value of the power supply voltage VBUS exceeds a starting voltage value according to the input first voltage; if yes, the voltage conversion module 20 is further configured to convert the power voltage VBUS into a first charging voltage VOUT and output the first charging voltage VOUT; the first charging voltage VOUT is lower than an overvoltage threshold of the charging module in a charging process;
The input end and the output end of the intelligent switch unit 10 are respectively coupled to the voltage output end of the voltage conversion module 20 and the charging input end of the charging module; the intelligent switch unit 10 is used for controlling the on-off of a branch circuit between the direct current power supply and the charging module, and the intelligent switch unit 10 is also used for maintaining the first current flowing through the intelligent switch unit 10 at a set target constant value in the quick charging process;
the first pin and the second pin of the logic control module 30 are respectively coupled to the current detection end of the intelligent switch unit 10 and the second output end of the first voltage division unit 40; the logic control module 30 is configured to:
detecting a value of the first current through the first pin;
detecting a value of the supply voltage VBUS from the second voltage input; and
according to the reduction degree of the value of the power supply voltage VBUS in the charging process, the target constant current value is adjusted; if the degree of decrease in the value of the supply voltage VBUS exceeds a first threshold, the logic control module 30 decreases the upper and lower limits of the target constant value; if the level of the decrease in the value of the supply voltage VBUS is below the first threshold value, the logic control module 30 maintains or increases the upper and lower limits of the target constant current value.
It should be noted that, the quick charging device may be a dedicated charging wire configured for consumer electronics, or may be a charging stand, and then the charging stand is connected to the consumer electronics through a common charging wire; such as a charging dock for a smart watch. Of course, the specific arrangement may be selected according to the requirements, and is not limited herein.
Referring to fig. 1, the first embodiment of the present invention solves the problems of circuit area occupation, excessive circuit cost and heat generation of the internal motherboard of the consumer electronic product caused by switching the charging chip in the existing fast charging scheme of the consumer electronic product by the above technical means; and on the basis of ensuring the charging stability, the charging efficiency is improved to the maximum extent. The principle is as follows:
in conventional solutions, a charging module of a consumer electronic product is generally provided with a battery pack of a power management chip device integrated with a Linear charging unit (i.e. a low-current Linear charging circuit) for charging. However, the scheme does not support constant current fast charging with large current, so the existing fast charging scheme replaces a power management chip integrated with a linear charging unit with a switch charging chip to realize constant current fast charging. The present embodiment now multiplexes the traditional scheme, namely replacing the switch charging chip with a power management chip integrated with a linear charging unit; in order to realize constant current quick charging, the intelligent switch unit 10 capable of realizing constant current regulation is integrated into a charging device matched with a consumer electronic product, and a small-area and low-cost load switch chip is additionally integrated into a self charging module. Compared with the switch charging chip and the problems corresponding to the external power inductor L1 and the external large capacitor, the circuit cost and the circuit area occupation of the consumer electronic product can be greatly relieved, and the heating problem caused by the switch charging chip is solved.
In addition to the intelligent switch unit 10, the fast charging apparatus provided in this embodiment further includes a voltage conversion module 20, a logic control module 30, and a first voltage division unit 40.
The voltage conversion module 20 converts a supply voltage VBUS of the dc power supply into a first charging voltage VOUT; the first charging voltage VOUT is used to characterize an overvoltage threshold of the charging module during charging. Therefore, no matter how large the supply voltage VBUS is, the voltage conversion module 20 can convert the supply voltage VBUS that is greater than or far beyond the overvoltage threshold value into the safe first charging voltage VOUT; for example, the power voltage VBUS is 15V, the overvoltage threshold is above 5.0V, and the voltage conversion module 20 converts the 15V high voltage into 5V to safely charge the charging module. Of course, if the power voltage VBUS is smaller than 5V and larger than the starting voltage value, the first charging voltage VOUT output by the voltage conversion module 20 is as close to 5V as possible.
The first voltage dividing unit 40 divides the power supply voltage VBUS to obtain a first voltage and a second voltage, and outputs the first voltage and the second voltage to the enable terminal of the voltage conversion module 20 and the second pin of the logic control module 30, respectively. Because the voltage conversion module 20 is a high voltage tolerant device, the first voltage will be greater than the second voltage, but the first voltage and the second voltage are both essentially scaled down differently from the supply voltage VBUS, and are used to detect the supply voltage VBUS. The power supply voltage VBUS is configured to detect the power supply voltage VBUS according to the first voltage, and determine whether the power supply voltage VBUS exceeds a starting voltage value; if the voltage is lower than 3.6V, for example, the output capacity of the dc power supply is not able to charge the corresponding device, and the voltage conversion is not performed. If the voltage exceeds, for example, 3.6V, the voltage conversion operation is performed. The logic control module 30 is configured to detect the power supply voltage VBUS according to the second voltage; meanwhile, the logic control module 30 also detects the value of the first current through a first pin; during the charging process, if the degree of decrease of the supply voltage VBUS exceeds a first threshold, it indicates that the current output capability of the dc power supply is insufficient to support the current constant current fast charging, so the logic control module 30 decreases the upper limit and the lower limit of the target constant current value through the first pin until the degree of decrease of the supply voltage VBUS compared with the initial value is lower than the first threshold. If the degree of decrease of the supply voltage VBUS is lower than the first threshold, the current output capability of the dc power supply is sufficient to support the current constant current fast charging, so the logic control module 30 increases the upper limit and the lower limit of the target constant current value through the first pin until finding a critical target constant current value, where the degree of decrease of the supply voltage VBUS compared with the initial value is close to the first threshold, so as to improve the charging efficiency to the maximum extent. Or the logic control module 30 maintains the target constant value unchanged through the first pin. The first threshold may be set according to requirements, which is not limited herein.
The following describes other structures and other functions of the quick charge device according to the first embodiment of the present invention:
referring to fig. 3, as an embodiment, the power pin of the logic control module 30 is coupled to the output end of the voltage conversion module 20, the fourth pin of the logic control module 30 is coupled to the charging input end of the charging module, and the logic control module 30 is further configured to:
dividing the first charging voltage VOUT by a built-in voltage dividing circuit to supply power to the logic control module 30; and
analog-to-digital conversion is performed on the divided voltage of the first charging voltage VOUT to detect the first charging voltage VOUT; detecting the actual battery voltage of the battery assembly in the quick charge process through a charging input end of the charging module, and setting a target value of the first charging voltage VOUT according to the actual battery voltage; wherein the target value is larger than the actual battery voltage, and the difference value between the target value and the actual battery voltage is at least the product of the set target constant current value and the first on-resistance; and
comparing the detected first charging voltage VOUT with the target value; if the difference exists, the first charging voltage VOUT is corrected according to the difference after the difference is obtained.
The embodiment has the beneficial effects that: (1) The power supply terminal and the voltage detection terminal of the logic control module 30 are combined to simultaneously realize the power supply of the logic control module 30 and the detection of the first charging voltage VOUT, thereby saving the pin resources of the logic control module 30. (2) By approximating the first charging voltage VOUT to the actual battery voltage, the power consumption of the charging device during fast charging is reduced. Wherein, the minimum value formula and the maximum value formula of the difference are respectively:
Xmin＝R1*I1
xmax=r1×i1+y; wherein Xmin is used to characterize the minimum value of the difference; xmax is used to characterize the maximum value of the difference; r1 is used to characterize the first on-resistance; wherein the first on-resistance is used for representing the on-resistance when a current flows from the voltage output end of the voltage conversion module 20 to the passage of the battery assembly through the intelligent switch unit 10 and the load switch unit to be conducted; i1 is used to characterize the target constant current value; y is used to characterize the reserved voltage value. The benefit of setting the reserved voltage value is that: preventing frequent changes in the first charging voltage VOUT due to frequent changes in the target value; however, frequent changes of the first charging voltage VOUT may occupy excessive resources of the logic control module, thereby affecting other functions of the logic control module.
For example: on the premise that the current output capacity of the direct current power supply is enough to support the current set constant current quick charge; setting the target constant current value to be 2A, setting the minimum value of the first on-resistance to be 200mΩ, and setting the reserved voltage value to be zero, wherein the minimum value of the difference value=2a×200mΩ=400 mV; setting the target value=3.3v+0.4v=3.7v if the current voltage of the battery pack is 3.3V; when the battery pack continues to be charged to 3.32V, the first on-resistance cannot be adjusted because the path is already fully on at this time, and if the target value is still 3.7V, the difference will not actually continue to maintain the first current at 2A. Therefore, in order to ensure the efficiency of constant current fast charging, the target value can only be raised to 3.72V, and so on, the target value will be frequently adjusted, so that the first charging voltage VOUT is frequently changed. If the reserved voltage value is set to be 100mV, the target value is increased to 3.8V; in the same case where the battery pack is charged to 3.32V, there is room for adjusting the magnitude of the first on-resistance by adjusting the degree of conduction of the smart switching unit 10 so that the first current is maintained at 2A; only when the battery assembly is charged to 3.4 or more, the first current needs to be maintained at 2A by adjusting the target value. It should be noted that, the setting of the reserved voltage value needs to be balanced with the power consumption of the charging device, because the lower the reserved voltage value is, the lower the power consumption of the charging device is. But correspondingly, the more frequently the first charging voltage VOUT is changed. Of course, the specific data of the preset voltage value may be set according to actual requirements, which is not described herein.
Referring to fig. 4, as a specific embodiment, the voltage conversion module 20 specifically includes Buck DC-DC, an external power inductor L1 for efficient transduction, and an external bootstrap capacitor C1 for bootstrap voltage; the external power inductor L1 is coupled between the voltage output end of the Buck DC-DC and the input end of the intelligent switch unit 10; the external bootstrap capacitor C1 is coupled between the voltage output end of the Buck DC-DC and the bootstrap end of the Buck DC-DC. It should be noted that, in order to enable the first charging voltage VOUT to be stably output, the fast charging device further includes a voltage stabilizing capacitor C2; the regulated voltage is coupled between the input terminal of the intelligent switching unit 10 and ground.
Referring to fig. 5, as a specific embodiment, if the voltage conversion module 20 has a communication system, the quick charging device further includes a voltage regulating single line; a third pin of the logic control module 30 is coupled to the control end of the voltage conversion module 20 through the voltage regulating single wire; and outputs a voltage regulating signal to the control end of the voltage conversion module 20 according to the difference value; the voltage conversion module 20 is configured to correct the first charging voltage VOUT output by itself according to the voltage regulation signal. The voltage regulating single line is specifically a communication single line, and the logic control module 30 regulates the output voltage of the voltage conversion module 20, that is, the first charging voltage VOUT, through single line communication.
Referring to fig. 6, if the voltage conversion module 20 has no built-in communication system, the quick charging device further includes a second voltage division unit 50, a filtering unit 60, and a first resistor R1; the input end and the output end of the second voltage division unit 50 are respectively coupled to the output end of the voltage conversion module 20 and the sampling end of the voltage conversion module 20, and the first end of the second voltage division unit 50 is grounded; the second voltage dividing unit 50 is configured to perform a third voltage division on the first charging voltage VOUT to obtain a third voltage, and output the third voltage to the sampling end of the voltage conversion module 20; the input end and the output end of the filtering unit 60 are respectively coupled to the third pin of the logic control module 30 and the first end of the first resistor R1, and the first end of the filtering unit 60 is grounded; the second end of the first resistor R1 is coupled to the sampling end of the voltage conversion module 20;
the third pin of the logic control module 30 is configured to output a PWM signal corresponding to the duty cycle according to the difference value; the filtering unit 60 is configured to filter the PWM signal to obtain an average voltage and output the average voltage; the first resistor R1 is configured to increase the output impedance of the filtering unit 60, so that the average voltage is added to the sampling end of the voltage conversion module 20; the voltage conversion module 20 is configured to correct the self-output first charging voltage VOUT according to the sum of the average voltage and the third voltage. Wherein the filtering unit 60 includes a filtering resistor R2 and a filtering capacitor C3; the first end of the filter resistor R2 is coupled to the third pin of the logic control module 30, and the second end of the filter resistor R2 is coupled to the first end of the filter capacitor C3 and serves as an output end of the filter unit 60; the second end of the filter capacitor C3 is grounded. The second voltage dividing unit 50 includes a fourth voltage dividing resistor R3 and a fifth voltage dividing resistor R4; the first end of the fourth voltage dividing resistor R3 is coupled to the output end of the voltage conversion module 20, and the second end of the fourth voltage dividing resistor R3 is coupled to the first end of the fifth voltage dividing resistor R4 and serves as the output end of the second voltage dividing unit 50; the second end of the fifth voltage dividing resistor R4 is grounded.
Referring to fig. 7, as a specific embodiment, the intelligent switching unit 10 includes a main channel switching subunit 11 and a constant current regulating subunit 12; the first end and the second end of the main channel switch subunit 11 are respectively coupled to the voltage output end of the voltage conversion module 20 and the charging input end of the charging module, and the main channel switch subunit 11 is configured to control on-off of a branch between the dc power supply and the charging module according to on-off of the main channel switch subunit 11; the first end, the second end, the input end and the output end of the constant current regulating subunit 12 are respectively coupled to the first end and the second end of the main channel switch subunit 11, the current detecting end of the intelligent switch unit 10 and the control end of the main channel switch subunit 11; the constant current regulator subunit 12 is configured to detect the magnitude of the first current, and regulate the magnitude of the first current by controlling the conduction degree of the main channel switch subunit 11 under the control of the logic control module 30. The main channel switch unit at least comprises an NMOS tube or a PMOS tube. If the plurality of NMOS transistors are included, the plurality of NMOS transistors are connected in parallel; if the plurality of PMOS tubes are included, the plurality of PMOS tubes are connected in parallel. The constant current regulating subunit 12 is specifically a universal constant current regulating chip, and the constant current regulating chip can control on and off of the main channel switch subunit 11, and also can control the on degree of the main channel switch subunit 11, so as to control the magnitude of the first on resistance.
Referring to fig. 7, as a specific embodiment, the logic control module 30 is further configured to send a handshake signal to the charging module through the fourth pin to control the charging module to switch from the first state to the second state; wherein the first state is used for representing that the charging module is in a state of normal charging, and the second state is used for representing that the charging module is in a state of digital interactive authentication with the logic control module 30; if the digital interaction authentication is passed, the charging module is characterized to accept quick charging;
the logic control module 30 is further configured to send a first signal to the charging module to control the charging module to switch from the second state to the first state.
The logic control module 30 is further configured to:
before sending the handshake signal, switching off the intelligent switching unit 10 by sending a second signal to the intelligent switching unit 10; and
before transmitting the first signal, a third signal is transmitted to the smart switching unit 10 to turn on the smart switching unit 10.
The logic control unit includes an MCU processor, however, the logic control unit may also include other data processing chips, such as an MPU, etc., which is not limited herein.
Referring to fig. 7, as a specific embodiment, the first voltage dividing unit 40 includes a first voltage dividing resistor R5, a second voltage dividing resistor R6, and a third voltage dividing resistor R7; the first end and the second end of the first voltage dividing resistor R5 are coupled to the output end of the dc power supply and the first end of the second voltage dividing resistor R6, respectively, and the second end of the first voltage dividing resistor R5 is used as the first output end of the first voltage dividing unit 40; the second end of the second voltage dividing resistor R6 is coupled to the first end of the third voltage dividing resistor R7 and is used as the second output end of the first voltage dividing unit 40; the second end of the third voltage dividing resistor R7 is grounded.
Referring to fig. 8, a second embodiment of the present invention provides a charging module, matched with the quick-charging device, for charging a battery assembly in the consumer electronic product, the charging module includes a power management chip 70 integrated with a linear charging unit and a load switch unit 80;
the input end of the power management chip 70 is used as a charging input end of the charging module; the output terminal of the linear charging unit is coupled to the positive electrode of the battery assembly, and the power management chip 70 is also coupled to the control terminal of the load switching unit 80; the power management chip 70 is configured to:
Converting the input first charging voltage VOUT into a second charging voltage and outputting the second charging voltage to the positive electrode of the battery assembly so as to perform first charging on the battery assembly; and
performing digital interactive authentication with the logic control module 30 according to the inputted handshake signal; if the authentication is passed, the receiving is indicated to enter a quick charge state; and controls the load switching unit 80 to be turned on when the voltage of the battery pack is greater than a second threshold value;
the input and output terminals of the load switch unit 80 are coupled to the input terminal of the power management chip 70 and the positive electrode of the battery assembly, respectively; the load switch unit 80 is configured to, after being controlled to be turned on, directly sink the first current input by the charging input terminal into the positive electrode of the battery assembly, so as to rapidly charge the battery assembly.
Setting an overvoltage critical value of the charging module in a charging process to be 5V, and setting the supported maximum charging current to be 2A; the minimum value of the first on-resistance is set to be 200mΩ, and the reserved voltage value is set to be 100mV, and a specific charging procedure of the charging module is described below according to the above setting:
a precharge phase: the phase charging module charges the battery component through the linear charging unit; because the linear charging unit is not internally provided with a high-frequency switch loop, high-current fast charging is not supported. At this time, the intelligent switch unit 10 in the fast charging device correspondingly sets the first current between 100mA and 200mA, and the voltage conversion module 20 converts the power supply voltage VBUS into 5V to perform slow charging on the battery assembly until the voltage of the battery assembly reaches a preset value capable of entering fast charging. The fast-charge preset value of consumer electronic products such as smart watches, smart bracelets, smart glasses, etc. is typically set to around 3V. Before the voltage of the battery assembly reaches a fast-charging preset value, the logic control module 30 controls the intelligent switch unit 10 to be turned off through a first pin; then, a handshake signal with a specific waveform is sent to the power management chip 70 in the charging module through the fourth pin, and digital interaction authentication is carried out with the power management chip 70 so as to confirm whether the quick charging can be received or not to the power management chip 70; when the digital interactive authentication passes, it means that the power management chip 70 receives the quick charge, and the logic control module 30 then controls the intelligent switching unit 10 to resume conducting through the first pin to continue to charge the battery pack.
Constant-current quick charging stage: when the voltage of the battery pack reaches a fast-charging preset value, for example, 3V, the power management chip 70 controls the load switch unit 80 to be turned on to establish a direct charging path from the charging input terminal of the charging module to the positive electrode of the battery pack. At this time, the intelligent switch unit 10 in the quick charging device correspondingly sets the target constant current value to about 2A; for example, 1.8A-2.2A. The logic control module 30 detects the actual voltage value of the battery assembly through the fourth pin, and determines the target value=3v+2a×200mΩ+100deg.mV=3.5v of the first charging voltage VOUT according to the actual voltage value of the battery assembly, the minimum value of the first on-resistance, the target constant value and the preset voltage value, and the logic control module 30 then controls the first charging voltage VOUT output by the voltage conversion module 20 to approach 3.5V through the third pin. When the voltage of the battery assembly rises to 3.1V, the target value of 3.5V will not continue to maintain the first current at the target constant value, and the target value is adjusted to 3.6V. When the voltage of the battery pack rises to 3.2V, the target value is adjusted to 3.7V. According to the charging mode, when the voltage of the battery assembly is gradually increased, the magnitude of the first charging voltage VOUT is correspondingly regulated, and the voltage of the first charging voltage VOUT and the voltage of the battery assembly are ensured to be kept between 0.4V and 0.5V, so that the power consumption of the quick charging device in the constant-current quick charging process is reduced. During the constant current quick charge process, the logic control module 30 detects the falling degree of the power supply voltage VBUS in real time; if the degree of decrease exceeds the first threshold, it indicates that the current dc power supply cannot output the constant current of 2A, and the target constant current value needs to be decreased to adapt to the current output capability of the current dc power supply.
When the battery pack is nearly full, for example, 4.35V is now commonly fully charged, and up to 4.35V or nearly 4.35V is now charged, in order to prevent overcharging the battery pack and damaging the cells in the battery pack, the load switch unit 80 is typically selected to be turned off, and the battery pack is charged again with a constant voltage and a small current through the linear charging unit until full. However, since the battery pack itself has internal resistance, the battery voltage measured by the logic control module 30 through the fourth pin is respectively composed of the voltage actually stored in the battery pack and the self voltage drop of the battery pack; for example, the internal resistance of the battery assembly itself is 100mΩ, and when 2A constant current fast charge is performed, the self voltage drop of the battery assembly=100 mΩ×2a=0.2v; when switching from 2A constant current fast charge to constant voltage slow charge below 200mA, the self-voltage drop of the battery assembly will be reduced by at least 100mΩ×2a—100mΩ×200ma=0.18v, so that the battery voltage detected by the logic control module 30 is reduced from 4.35V to 4.17V; this lack of 0.18V will additionally increase the constant voltage charging time. In order to reduce the constant voltage charging time as much as possible and improve the charging efficiency; when the battery pack is charged to 4.35V, the logic control module 30 controls the intelligent switching unit 10 to decrease the target constant current value to about 1A, and the detected battery voltage is reduced to 4.25V; when the voltage of the battery pack is recharged to 4.35V, the logic control module 30 controls the intelligent switching unit 10 to decrease the target constant current value to about 0.5A, and the detected battery voltage is reduced to 4.30V; according to the above method, the degree of decrease in the detected battery voltage is negligible until the switching to constant voltage charging is performed.
Constant pressure slow charging stage: the power management chip 70 turns off the load switch unit 80 and re-switches the linear charging unit to charge; at this time, the voltage conversion module 20 in the fast charging device converts the power voltage VBUS to 5V, and the first current is about 100mA to perform slow charging on the battery assembly; and stopping charging until the first current is smaller than 20 mA.
Of course, the data in the specific charging flow of the charging module is just one specific implementation, and the actual data may be adjusted according to the requirement, which is not limited herein.
A third embodiment of the invention provides a consumer electronic product comprising the charging module.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and not for limiting the same; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the invention.