CN116505631B

CN116505631B - Single-input multi-output charging circuit and wearable device

Info

Publication number: CN116505631B
Application number: CN202310783867.8A
Authority: CN
Inventors: 王玉麟
Original assignee: Shenzhen Weiyuan Semiconductor Co ltd
Current assignee: Shenzhen Weiyuan Semiconductor Co ltd
Priority date: 2023-06-29
Filing date: 2023-06-29
Publication date: 2024-02-09
Anticipated expiration: 2043-06-29
Also published as: CN116505631A

Abstract

The utility model provides a single input multi-output's charging circuit and wearable equipment, wherein, single input multi-output's charging circuit includes a charge energy storage circuit, a plurality of discharge circuit, a plurality of sampling circuit and a constant current control circuit, constant current control circuit control charge energy storage circuit circulation many times charges, simultaneously, control a plurality of discharge circuit circulation timesharing discharges, thereby realize carrying out cyclic charge to a plurality of power receiving modules, and, constant current control circuit adjusts the duty cycle of charge energy storage circuit according to the actual charge current that samples and charge voltage and preset electric parameter, realize charge-discharge's feedback regulation and constant current charge, improve each power receiving module's charge efficiency, simultaneously, need not to set up too much inductance structure, system architecture has been simplified, and design cost has been reduced.

Description

Single-input multi-output charging circuit and wearable device

Technical Field

The application belongs to the technical field of charging, and particularly relates to a single-input multi-output charging circuit and wearable equipment.

Background

In recent years, wearable devices are popular and popularized in a large area, and for commonly used wearable products, such as a TWS (true-wireless stereo) earphone, a wireless microphone, a smart glasses and the like, the product form of the wearable device has a basic characteristic that a power supply module, such as a large battery, charges a plurality of power receiving modules (for example, batteries 1 to n), and a conventional charging mode is that a battery compartment increases the voltage of the large battery to a voltage with a preset magnitude through a voltage increasing and decreasing circuit, for example, the output voltage of the large battery is increased and decreased to 5v, and 5v is independently output to the corresponding power receiving modules of the batteries 1 to n through a plurality of load switches. The batteries 1-n are connected with corresponding charging chips (linear charging or switching charging) and are charged by reducing 5V to battery voltage.

The linear charging mode has the lowest cost, but the full-link charging efficiency of the whole system from the battery end of the battery compartment to the battery end of the powered device is lower, and basically only 50-70% of energy conversion rate is different. The switch charging mode is efficient, but each power receiving module needs a power inductor, so that the wearable equipment cannot be miniaturized, and meanwhile, the system cost is increased.

Disclosure of Invention

The purpose of the application is to provide a single-input multi-output charging circuit, and aims to solve the problems of low efficiency and complex structure existing in a traditional charging mode.

A first aspect of an embodiment of the present application proposes a single input multiple output charging circuit, including:

the input end of the charging energy storage circuit is used for being connected with the power end of the power supply module and receiving a power supply, and the charging energy storage circuit is triggered to perform charging energy storage work for a plurality of times in a circulating way by PWM (pulse width modulation) signals at a plurality of circulating intervals;

the input ends of the discharge circuits are respectively connected with the output end of the charging energy storage circuit in parallel, the output end of each discharge circuit is used for being connected with the power end of the power receiving module, and the discharge circuits are triggered to be conducted at a cycle interval by switching signals at a plurality of cycle intervals so as to perform cycle discharge operation on stored electric energy of the charging energy storage circuit for a plurality of times according to a corresponding time sequence;

The first sampling circuits are respectively connected with the charging energy storage circuit and the discharging circuits one by one, and each first sampling circuit is used for sampling the average output current and the output voltage of each discharging circuit and outputting a first sampling signal;

the constant current control circuit is respectively connected with the charging energy storage circuit, the discharging circuits and the first sampling circuits and is used for:

outputting PWM modulation signals and switching signals with a plurality of cycle intervals;

and determining the duty ratio of the PWM modulation signal during the ith charging of the charging energy storage circuit in the next cycle period according to the average output current, the output voltage, the preset average output current and the preset output voltage of the ith discharging circuit so as to perform constant-current charging control on each power receiving module, wherein i=1, 2.

Optionally, the charging energy storage circuit comprises a first electronic switch tube and an inductor;

the first end of the inductor forms the input end of the charging energy storage circuit, the second end of the inductor is connected with the second end of the first electronic switch tube to form the output end of the charging energy storage circuit, and the second end of the first electronic switch tube is grounded.

Optionally, the charging energy storage circuit comprises a second electronic switch tube, a third electronic switch tube and an inductor;

the first end of the second electronic switching tube forms the input end of the charging energy storage circuit, the second end of the second electronic switching tube, the first end of the third electronic switching tube and the first end of the inductor are connected, the second end of the third electronic switching tube is grounded, and the second end of the inductor forms the output end of the charging energy storage circuit.

Optionally, the charging energy storage circuit comprises a first electronic switching tube, a second electronic switching tube, a third electronic switching tube and an inductor;

the first end of the second electronic switch tube forms the input end of the charging energy storage circuit, the second end of the second electronic switch tube, the first end of the third electronic switch tube and the first end of the inductor are connected, the second end of the third electronic switch tube is grounded, the second end of the inductor and the first end of the first electronic switch tube are connected to form the output end of the charging energy storage circuit, and the second end of the first electronic switch tube is grounded.

Optionally, the discharging circuit includes a discharging switch and a capacitor;

the first end of the discharge switch forms an input end of the discharge circuit, the second end of the discharge switch is connected with the first end of the capacitor to form an output end of the discharge circuit, the second end of the capacitor is grounded, and the control end of the discharge switch forms a control end of the discharge circuit;

Wherein at least one of the two discharge switches of adjacent branches is in an off state.

Optionally, the discharge switch includes a first PMOS tube and a second PMOS tube;

the drain electrode of the first PMOS tube forms a first end of the discharge switch, the source electrode of the first PMOS tube is connected with the source electrode of the second PMOS tube, the drain electrode of the second PMOS tube forms a second end of the discharge switch, and the grid electrodes of the first PMOS tube and the second PMOS tube are respectively connected with the signal end of the constant current control circuit;

and the second PMOS tube of the ith discharging switch triggers to be conducted in dead time before the ith discharging switch to be conducted is conducted, so that the residual charge of the inductor is released in a follow current mode.

Optionally, the discharge switch comprises a transistor, a first diode, a first switch, a second diode and a second switch which adopt a switching substrate connection method;

the anode of the first diode, the first end of the first switch and the first end of the transistor are connected to form a second end of the discharge switch, the anode of the second diode, the first end of the first switch and the first end of the transistor are connected to form a first end of the discharge switch, the cathode of the first diode is connected to the second end of the first switch, and the cathode of the second diode is connected to the second end of the second switch;

When the grid electrode of the transistor receives low level, the second switch is triggered to be turned on, and the first switch is triggered to be turned off;

and when the grid electrode of the transistor receives a high level, the second switch is triggered to be conducted when the output end voltage of the transistor is larger than the input end voltage, and the first switch is triggered to be conducted when the output end voltage of the transistor is smaller than or equal to the input end voltage.

Optionally, the single-input multiple-output charging circuit further includes:

the second sampling circuit is respectively connected with the charging energy storage circuit and the constant current control circuit, and is used for sampling the charging current of the charging energy storage circuit and outputting a second sampling signal to the constant current control circuit;

the constant current control circuit includes:

the comparison trigger circuits are respectively connected with the first sampling circuit and the second sampling circuit, and are also used for receiving a clock signal with a corresponding phase, and the comparison trigger circuits are used for determining the duty ratio of a PWM modulation signal when the charging energy storage circuit is charged for the ith time in the next cycle period according to the average output current, the output voltage, the preset average output current, the preset output voltage and the charging current of the ith discharging circuit and determining the output moment of the PWM modulation signal according to the high-level pulse of the clock signal;

The logic control circuit is respectively connected with each comparison trigger circuit, each charging energy storage circuit and each discharging circuit, and is used for receiving a plurality of PWM modulation signals and outputting each PWM modulation signal and each switching signal according to corresponding time sequences so as to perform constant-current charging control on each power receiving module;

the clock signals received by the comparison trigger circuits are respectively different from each other by a preset phase.

Optionally, the comparison trigger circuit includes a voltage error amplifier, a current error amplifier, a compensation circuit, a first comparator, and a trigger;

the positive phase input end of the voltage error amplifier is used for inputting the preset output voltage, the negative phase input end of the voltage error amplifier is used for inputting sampling values of the output voltage, the positive phase input end of the current error amplifier is used for inputting preset average output current, the negative phase input end of the current error amplifier is used for inputting sampling values of the average output current, the output end of the voltage error amplifier, the output end of the current error amplifier, the output end of the compensation circuit and the positive phase input end of the first comparator are connected, the negative phase input end of the first comparator is used for inputting sampling values of the charging current, the output end of the first comparator is connected with the reset end of the trigger, and the setting end of the trigger is used for inputting the clock signal.

Optionally, the single-input multiple-output charging circuit further includes:

the full-power detection circuits are respectively connected with the constant current control circuit and the discharge circuit, and are used for detecting the output current of each discharge circuit and outputting full-power detection signals to the constant current control circuit when the output current of the discharge circuit is smaller than a preset current;

and the constant current control circuit is also used for triggering a discharge circuit connected with the ith power receiving module to maintain an off state when receiving a full power detection signal output by the full power detection circuit corresponding to the ith power receiving module.

Optionally, the full power detection circuit includes a current transformer and a second comparator;

the current transformer is connected with the input end of the discharging circuit, the output end of the current transformer is connected with the inverting input end of the second comparator, the non-inverting input end of the second comparator is used for inputting a preset current value, and the output end of the second comparator forms the output end of the full-power detection circuit.

Optionally, the single-input multiple-output charging circuit further includes:

the system comprises a discharge circuit, a constant current control circuit, a plurality of bin outlet detection and communication circuits, a bin outlet detection and communication circuit and a control circuit, wherein the discharge circuit is connected with the constant current control circuit, and the bin outlet detection and communication circuit is used for:

Detecting the in-out bin state of the power receiving module and outputting an in-out bin detection signal to the constant current control circuit;

and establishing bidirectional communication between the power supply module and the power receiving module.

Optionally, the single-input multi-output charging circuit further comprises a plurality of charging interfaces and load switches, wherein the charging interfaces and the load switches are respectively connected with the power receiving modules one by one, each charging interface comprises a positive charging interface and a negative charging interface, the load switches are connected between the negative charging interface and the ground in series, and the output end of the discharging circuit is connected with the positive charging interface;

the access bin detection and communication circuit comprises a fourth electronic switching tube, a fifth electronic switching tube, a sixth electronic switching tube, a current source and a third comparator;

the first end of the fourth electronic switching tube, the positive phase input end of the third comparator and the positive charging interface are connected, the second end of the fourth electronic switching tube and the first end of the fifth electronic switching tube are connected and connected with a positive power supply end, the second end of the fifth electronic switching tube, the first end of the sixth electronic switching tube, the output end of the current source, the inverting input end of the third comparator and the negative charging interface are connected, the second end of the sixth electronic switching tube is grounded, and the output end of the comparator forms a signal output end of the in-out bin detection and communication circuit.

The second aspect of the embodiment of the application provides a wearable device, which comprises a power supply module, a plurality of power receiving modules and the single-input multi-output charging circuit, wherein the single-input multi-output charging circuit is used for connecting the power supply module and the power receiving modules and performing charging and discharging operations.

Compared with the prior art, the embodiment of the application has the beneficial effects that: the single-input multi-output charging circuit comprises a charging energy storage circuit, a plurality of discharging circuits, a plurality of sampling circuits and a constant current control circuit, wherein the constant current control circuit controls the charging energy storage circuit to circularly charge for a plurality of times, and simultaneously controls the plurality of discharging circuits to circularly and time-division discharge, so that a plurality of power receiving modules are circularly charged, and the constant current control circuit adjusts the duty ratio of the charging energy storage circuit according to the sampled actual charging current, charging voltage and preset electric parameters, so that the charging and discharging feedback adjustment and constant current charging are realized, the charging efficiency of each power receiving module is improved, and meanwhile, too many inductance structures are not required to be arranged, the system structure is simplified, and the design cost is reduced.

Drawings

Fig. 1 is a schematic structural diagram of a power receiving module according to an embodiment of the present application;

Fig. 2 is a schematic diagram of a first configuration of a single input multiple output charging circuit according to an embodiment of the present disclosure;

fig. 3 is a schematic signal waveform diagram of a single input multiple output charging circuit according to an embodiment of the present disclosure;

fig. 4 is a schematic diagram of a second configuration of a single input multiple output charging circuit according to the first embodiment of the present application;

FIG. 5 is a schematic diagram of a clock signal of a single-input multi-output charging circuit according to an embodiment of the present disclosure;

FIG. 6 is a schematic circuit diagram of a full power detection circuit in the single-input multiple-output charging circuit shown in FIG. 4;

fig. 7 is a schematic circuit diagram of a single input multiple output charging circuit according to a second embodiment of the present disclosure;

fig. 8 is a schematic circuit diagram of a single-input multiple-output charging circuit according to a third embodiment of the present application;

fig. 9 is a schematic circuit diagram of a single-input multiple-output charging circuit according to a fourth embodiment of the present application;

FIG. 10 is a schematic diagram of a first circuit of a discharge switch in the single-input-multiple-output charging circuit shown in FIG. 9;

FIG. 11 is a second circuit schematic of the discharge switch in the single-input-multiple-output charging circuit shown in FIG. 9;

fig. 12 is a schematic structural diagram of a single-input multiple-output charging circuit according to a fifth embodiment of the present application;

FIG. 13 is a schematic diagram of a comparison trigger circuit in the single-input multiple-output charging circuit shown in FIG. 12;

fig. 14 is a schematic structural diagram of a single-input multiple-output charging circuit according to a sixth embodiment of the present application;

FIG. 15 is a schematic circuit diagram of the detection and communication circuit for the access bin in the single-input multiple-output charging circuit shown in FIG. 14;

fig. 16 is a schematic structural diagram of a wearable device according to a sixth embodiment of the present application.

Detailed Description

In order to make the technical problems, technical schemes and beneficial effects to be solved by the present application more clear, the present application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the present application.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present application, the meaning of "a plurality" is two or more, unless explicitly defined otherwise.

Example 1

In the first aspect of the embodiment of the present application, a single input and multiple output charging circuit 100 is provided for implementing cyclic time-sharing charging of multiple power receiving modules 300 by a single power supplying module 200, where the power supplying module 200 and the power receiving modules 300 may be matching modules in a wearable device, such as an earphone cabin and an earphone assembly in a TWS earphone, when the earphone assembly is placed in the earphone cabin and reliably connected, the earphone cabin charges left and right earphone assemblies through an internal battery BAT1 and the single input and multiple output charging circuit 100, the power receiving modules 300 include at least two power receiving modules 300, and an energy storage module or other energy consumption modules, such as a sub-battery 320, may be included in the power receiving modules 300, as shown in fig. 2, and when the power receiving modules 320 are the sub-battery 320, the power receiving modules 300 may further include a connected charging chip 310, where the charging chip 310 is configured to perform battery BAT1 management charging on the input charging power supply, optionally, and when each charging is performed, the charging chip 310 sets the sub-battery 320 current to a real target charging current, and the charging current is set to a preset charging current, and the preset charging current is set to be the preset charging current, and the preset charging current is greater than the target charging current, and the preset charging current is set to be a through the charging current.

In order to improve the charging efficiency and simplify the structure of the wearable device, and achieve miniaturization of the wearable device, a single-input multi-output charging circuit 100 is proposed, as shown in fig. 1, the charging circuit 100 includes:

the input end of the charging energy storage circuit 10 is used for connecting the power end of the power supply module 200 and receiving a power supply, and the charging energy storage circuit 10 is triggered to perform charging energy storage work for a plurality of times by PWM modulation signals with a plurality of cycle intervals;

the input ends of the discharge circuits 20 are respectively connected with the output ends of the charging energy storage circuits 10 in parallel, the output end of each discharge circuit 20 is used for being connected with the power end of the power receiving module 300, and the discharge circuits 20 are triggered to be conducted at a cycle interval by switching signals at a plurality of cycle intervals so as to perform cycle discharge operation on stored electric energy of the charging energy storage circuits 10 for a plurality of times according to corresponding time sequences;

the first sampling circuits 30 are respectively connected with the charging energy storage circuit 10 and the discharge circuits 20 one by one, and each first sampling circuit 30 is used for sampling the average output current and the output voltage of each discharge circuit 20 and outputting a first sampling signal;

The constant current control circuit 40 is connected to the charge energy storage circuit 10, the plurality of discharge circuits 20 and the plurality of first sampling circuits 30, respectively, and the constant current control circuit 40 is configured to:

and determining the duty ratio of the PWM modulation signal during the ith charging of the charge storage circuit 10 in the next cycle period according to the average output current, the output voltage, the preset average output current and the preset output voltage of the ith discharge circuit 20, so as to perform constant current charging control on each power receiving module 300, wherein i=1, 2..n, n is the number of discharge circuits 20 to be discharged.

In this embodiment, after each power receiving module 300 to be charged is reliably connected to the charging circuit 100, the constant current control circuit 40 performs periodic and cyclic charge-discharge control operation, during initial charge-discharge, each discharging circuit 20 is in an off state, the constant current control circuit 40 outputs a first PWM modulation signal to the charge energy storage circuit 10, the charge energy storage circuit 10 performs switching and charge energy storage according to the PWM modulation signal, after charging, the constant current control circuit 40 outputs the first switching signal to the first discharging circuit 20, the discharging circuit 20 is turned on, the charge energy storage circuit 10 stores electric energy and outputs the electric energy to the first power receiving module 300 through the first discharging circuit 20, and meanwhile, the first sampling circuit 30 obtains the output current and the output voltage of the current first discharging circuit 20 and compares the preset average output current and the preset output voltage matched with the first power receiving module 300, so as to adjust the duty ratio of the PWM modulation signal of the charge energy storage circuit 10 for supplying power to the first discharging circuit 20 next time, thereby adjusting the average output current of the first power receiving module 300 next time to be close to the preset average output current and achieve constant current.

After the first power receiving module 300 is charged for the first time, the first discharging circuit 20 is turned off, the charging energy storage circuit 10 receives the PWM modulation signal again, the charging energy storage circuit 10 charges and stores energy again, after the charging is finished, the constant current control circuit 40 outputs a second switching signal to the second discharging circuit 20, the discharging circuit 20 is turned on, the electric energy stored by the charging energy storage circuit 10 at this time is output to the second power receiving module 300 through the second discharging circuit 20, meanwhile, the first sampling circuit 30 connected with the second discharging circuit 20 obtains the output current and the output voltage of the current second discharging circuit 20, and the preset average output current matched with the second power receiving module 300 is compared with the preset output voltage, so that the duty ratio of the PWM modulation signal of the charging energy storage circuit 10 for supplying energy to the second discharging circuit 20 for the next time is adjusted, and the average output current of the first power receiving module 300 for the next time is adjusted, so that the electric energy is close to the preset average output current, and constant current charging is realized.

And so on, the charging energy storage circuit 10 controls the charging energy storage circuit 10 to charge for a plurality of times and controls the discharging circuits 20 to discharge in sequence in a single period, so as to respectively provide a charging power supply for the power receiving modules 300, and in the next period, controls the charging energy storage circuit 10 to charge for a plurality of times and controls the discharging circuits 20 to discharge in sequence again, and respectively provides a charging power supply for the power receiving modules 300 again until the power receiving modules 300 are finished after full power is supplied for a plurality of periods, so that the multi-cycle constant current charging is realized.

Assuming that the power receiving modules 300 include two power receiving modules, referring to fig. 3, it is assumed that an average output current of the first discharging circuit 20 connected to the first power receiving module 300 is IOUT1, an output voltage is VOUT1, a preset average output current of the first power receiving module 300 is Iref1, a preset output voltage is Vref1, an average output current of the second discharging circuit 20 connected to the second power receiving module 300 is IOUT2, an output voltage is VOUT2, a preset average output current of the second power receiving module 300 is Iref2, a preset output voltage is Vref2, wherein VEA1 is a preset peak current of the charging energy storage circuit 10 corresponding to the preset average output current Iref1 and the preset output voltage Vref1 of the first discharging circuit 20, VEA2 is a preset peak current of the charging energy storage circuit 10 corresponding to the preset average output current Iref2 and the preset output voltage Vref2 of the second discharging circuit 20, CLK1 is a trigger clock signal of the charging energy storage circuit 10 before discharging the first discharging circuit 20, CLK2 is a trigger clock signal of the charging energy storage circuit 10 before discharging the second discharging, and IL is a real-time clock signal of the charging energy storage circuit 10.

When CLK1 is output as a high level pulse signal, the constant current control circuit 40 outputs a PWM modulation signal to the charge energy storage circuit 10, the charge energy storage circuit 10 starts to charge and store energy, when the peak current of the charge energy storage circuit 10 reaches VEA1, the constant current control circuit 40 controls the charge energy storage circuit 10 to turn off, the constant current control circuit 40 controls the first discharging circuit 20 to turn on, the charge energy storage circuit 10 discharges to the first power receiving module 300 through the first discharging circuit 20, when the current of the charge energy storage circuit 10 drops to zero, the constant current control circuit 40 controls the first discharging circuit 20 to turn off, the energy output of the VOUT1 path is finished, during discharging, the constant current control circuit 40 samples the average output current and the output voltage of the first discharging circuit 20 through the first sampling circuit 30 and compares with the preset average output current and the preset output voltage, and determines the duty ratio of the PWM modulation signal required by the charge energy storage circuit 10 before the first discharging circuit 20 according to the comparison result, thereby changing the charge energy of the charge energy storage circuit 10 in the next cycle of charging.

When the first discharging circuit 20 is turned off, CLK2 is switched to a high level pulse signal, the constant current control circuit 40 outputs a PWM modulation signal to the charging energy storage circuit 10, the charging energy storage circuit 10 performs charging energy storage again, when the peak current of the charging energy storage circuit 10 reaches VEA2, the constant current control circuit 40 controls the charging energy storage circuit 10 to turn off, the constant current control circuit 40 controls the second discharging circuit 20 to turn on, the charging energy storage circuit 10 discharges to the second power receiving module 300 through the second discharging circuit 20, when the current of the charging energy storage circuit 10 drops to zero, the constant current control circuit 40 controls the second discharging circuit 20 to turn off, the energy output of the VOUT2 path is finished, during discharging, the constant current control circuit 40 samples the average output current and the output voltage of the second discharging circuit 20 through the first sampling circuit 30 and compares the average output current and the preset output voltage with the matched average output current and preset output voltage, and determines the duty ratio of the modulation signal required by the charging energy storage circuit 10 before the second discharging according to the comparison result, so that the PWM electric energy of the next cycle of the charging energy storage circuit 10 is changed.

When the second discharging circuit 20 is turned off, CLK1 is switched to the high level pulse signal again, the constant current control circuit 40 outputs the adjusted PWM modulation signal to the charging energy storage circuit 10, the charging energy storage circuit 10 charges and discharges again, and discharges again to the first power receiving module 300 through the first discharging circuit 20, thereby realizing constant current output control of the first power receiving module 300.

Similarly, when the first discharging circuit 20 is turned off again, CLK2 is switched to the high-level pulse signal again, the constant-current control circuit 40 outputs the adjusted PWM modulation signal to the charge energy storage circuit 10, the charge energy storage circuit 10 charges and discharges again, and discharges again to the second power receiving module 300 through the second discharging circuit 20, thereby realizing constant-current output control of the second power receiving module 300.

The duty ratio of the PWM modulation signal is positive or negative correlated with the amount of the stored electric energy charged by the charge tank circuit 10, for example, the larger the duty ratio is, the larger the stored electric energy of the charge tank circuit 10 is, the smaller the duty ratio is, the smaller the stored electric energy of the charge tank circuit 10 is, and the specific mapping relationship is not limited.

Meanwhile, the duty ratio of the PWM modulation signal is positively or negatively correlated with the average output current and the output voltage of the discharge circuit 20, for example, when the output voltage does not reach the preset output voltage, the duty ratio of the PWM modulation signal that is output to the charge energy storage circuit 10 next time is increased when the average output current of the last discharge circuit 20 is smaller than the preset average output current, so as to increase the stored electric energy of the charge energy storage circuit 10, and the average output current of the next discharge circuit 20 next time is increased, so as to realize the cyclic constant current control of the discharge circuit 20, and when the output voltage does not reach the preset output voltage, the average output current of the last discharge circuit 20 is larger than the preset average output current, the duty ratio of the PWM modulation signal that is output to the charge energy storage circuit 10 next time is reduced, so as to reduce the stored electric energy of the charge energy storage circuit 10, and the average output current of the next time of the next discharge circuit 20 is reduced, so that the average output current of the same discharge circuit 20 in the multiple discharge processes is maintained at the preset average output current.

Meanwhile, when the output voltage reaches the preset output voltage, that is, the power receiving module 300 is charged to a full-power state, at this time, the duty ratio of the PWM modulation signal at the next time is adjusted to be reduced to a preset value or increased to a preset value, so as to reduce the charging current, and the power receiving module 300 enters a constant-voltage charging stage to clamp the charging voltage of the power receiving module 300 to a preset reference voltage.

Or when the output voltage reaches the preset output voltage, that is, the power receiving module 300 is charged to a full-power state, at this time, the duty ratio of the PWM modulation signal at the next time is adjusted to be zero or 100%, the discharging circuit 20 of the power receiving module 300 is turned off, the power receiving module 300 is charged by cut-off, the charging of the power receiving module 300 is finished, the constant current control circuit 40 skips the discharging circuit 20, and the remaining power receiving modules 300 are selected to be circularly charged and controlled by constant current.

In order to more accurately determine the full power of the power receiving modules 300 in the multi-path power receiving module 300, and implement selective charging, as shown in fig. 4, the single-input multi-output charging circuit 100 further includes:

the full power detection circuits 60 are respectively connected with the constant current control circuit 40 and the discharge circuit 20, and the full power detection circuits 60 are used for detecting the output current of each discharge circuit 20 and outputting full power detection signals to the constant current control circuit 40 when the output current of the discharge circuit 20 is smaller than a preset current;

The constant current control circuit 40 is further configured to trigger the discharge circuit 20 connected to the ith power receiving module 300 to maintain an off state when receiving a full power detection signal output by the full power detection circuit 60 corresponding to the ith power receiving module 300.

After the power receiving modules 300 are reliably connected and when each power receiving module 300 is charged, output current detection is performed on the matched discharging circuits 20 through the full power detection circuits 60 connected respectively in real time, when the fact that the output current of one discharging circuit 20 is smaller than the preset current is detected, the current power receiving module 300 is in a full power state, charging is not needed, at the moment, the constant current control circuit 40 controls the discharging circuit 20 of the power receiving module 300 to be turned off or to maintain the off state, and meanwhile, for a branch circuit which does not need to be charged, automatic skipping is selected.

Taking the three-way power receiving module 300 as an example, when the first power receiving module 300 is full after n times of cyclic charging in the charging process, the second power receiving module 300 and the third power receiving module 300 are not full after n times of cyclic charging, at this time, the constant current control circuit 40 controls the discharging circuit 20 connected with the first power receiving module 300 to be turned off, and in the n+1th cyclic charging process, the second power receiving module 300 and the third power receiving module 300 are circularly charged, and when the second power receiving module 300 is full in the m times of cyclic charging process, the constant current control circuit 40 only circularly charges the third power receiving module 300 until the three power receiving modules 300 are full, thereby realizing high-efficiency charging and avoiding the idle load of the first power receiving module 300 or the second power receiving module 300 from reducing the charging efficiency.

Meanwhile, in the process of charging each power receiving module 300, as each power receiving module 300 is fully charged, the discharge time sequence of each power receiving module 300 which is not fully charged can be correspondingly advanced, the specific advanced time sequence can be adjusted according to the preset output voltage and the preset average output current of the power receiving module 300, for example, if the preset output voltage and the preset average output current of each power receiving module 300 are the same, the adjacent charge time interval and the discharge time interval are equal, as shown in fig. 5, when all three power receiving modules 300 are not fully charged, the discharge time sequence of the first discharge circuit 20 to the first power receiving module 300 is T1, the discharge time sequence of the second discharge circuit 20 to the second power receiving module 300 is T2, the discharge time sequence of the third discharge circuit 20 to the third power receiving module 300 is T3, after the first power receiving module 300 is fully charged, the second power receiving module 300 is taken as a new first power receiving module 300, the discharge time sequence T1 of the first power receiving module 300 is taken as an adjusted discharge time sequence, the discharge time sequence of the third power receiving module 300 is taken as a new first power receiving module 300, the discharge time sequence of the second power receiving module 300 is taken as a subsequent charge waiting time sequence of the second power receiving module 300 is adjusted, and the discharge time sequence of the second power receiving module 300 is reduced, and accordingly, the discharge time sequence of the second power receiving module 300 is taken after the charge is adjusted is reduced.

The full power detection circuit 60 may adopt a transformer, a sampling resistor, and the like, as shown in fig. 6, and optionally, the full power detection circuit 60 includes a current transformer CT1 and a second comparator CMP2;

the current transformer CT1 is connected to the input end of the discharging circuit 20, the output end of the current transformer CT1 is connected to the inverting input end of the second comparator CMP2, the non-inverting input end of the second comparator CMP2 is used for inputting a preset current value, and the output end of the second comparator CMP2 forms the output end of the full power detection circuit 60.

The current transformer CT1 is configured to perform mutual inductance output on an output current of the discharge circuit 20 and output a small current to the second comparator CMP2, the second comparator CMP2 compares the output current with a preset current value, when the output current is smaller than the preset current value, the second comparator CMP2 outputs a high level, which indicates that the current power receiving module 300 is not full, the constant current control circuit 40 continues to control the discharge circuit 20 connected to the power receiving module 300 to participate in the cyclic discharge operation, and when the output current reaches the preset current value, the second comparator CMP2 outputs a low level, which indicates that the current power receiving module 300 is full, the constant current control circuit 40 triggers the discharge circuit 20 connected to the power receiving module 300 to exit the cyclic discharge operation, and controls the residual discharge circuit 20 to perform cyclic charge and constant current control.

The first sampling circuit 30 is used for sampling the average output current and output voltage of each discharge circuit 20, and may also sample structures such as a transformer and a resistor, and the specific structure is not limited.

The charging tank circuit 10 may employ an inductor L, a capacitor, etc. and a switch structure, and the specific structure is not limited.

The discharge circuit 20 may be configured with a controlled on-off switch, such as a power switch, a relay, etc., and the specific configuration is not limited.

The constant current control circuit 40 may adopt a structure such as a processor and a comparator, and processes and compares the sampled signals and outputs the circulated PWM modulation signal and the switching signal correspondingly, thereby controlling each power receiving module 300 to perform constant current charging.

Compared with the prior art, the embodiment of the application has the beneficial effects that: the single-input multi-output charging circuit 100 is composed of a charging energy storage circuit 10, a plurality of discharging circuits 20, a plurality of sampling circuits and a constant current control circuit 40, wherein the constant current control circuit 40 controls the charging energy storage circuit 10 to circularly charge for a plurality of times, and simultaneously controls the plurality of discharging circuits 20 to circularly and time-sharing discharge, so that the plurality of power receiving modules 300 are circularly charged, and the constant current control circuit 40 adjusts the duty ratio of the charging energy storage circuit 10 according to the sampled actual charging current, charging voltage and preset electrical parameters, so that the feedback regulation of charging and discharging and constant current charging are realized, the charging efficiency of each power receiving module 300 is improved, and meanwhile, too many inductance L structures are not required to be arranged, the system structure is simplified, and the design cost is reduced.

Example two

Based on the embodiment one, as shown in fig. 7, in an alternative embodiment, the charging energy storage circuit 10 includes a first electronic switch tube Qboost and an inductor L, a first end of the inductor L forms an input end of the charging energy storage circuit 10, a second end of the inductor L is connected with a second end of the first electronic switch tube Qboost to form an output end of the charging energy storage circuit 10, and a second end of the first electronic switch tube Qboost is grounded.

The discharging circuit 20 includes a discharging switch and a capacitor, for example, a first discharging switch q1_1 and a first capacitor c1_1, a second discharging switch q1_2 and a second capacitor c1_2, etc., where a first end of the discharging switch forms an input end of the discharging circuit 20, a second end of the discharging switch and a first end of the capacitor are connected to form an output end of the discharging circuit 20, a second end of the capacitor is grounded, and a control end of the discharging switch forms a control end of the discharging circuit 20, where at least one of two discharging switches of adjacent branches is in an off state.

The single-input multi-output charging circuit 100 further includes a plurality of charging interfaces and load switches, such as a first load switch q2_1 and a second load switch q2_2, for connecting with the plurality of power receiving modules 300 one by one, where each charging interface includes a positive charging interface and a negative charging interface, such as a first positive charging interface p1+ and a first negative charging interface P1-, a second positive charging interface p2+ and a negative charging interface P2-, where the load switches are connected in series between the negative charging interface and ground, and an output terminal of the discharging circuit 20 is connected with the positive charging interface.

In this embodiment, a plurality of discharge switches, a first electronic switching tube Qboost and an inductor L form a single-input multi-output boost converter circuit, the first electronic switching tube Qboost forms an upper tube of the boost converter circuit, the plurality of discharge switches form a lower tube of the boost converter circuit, and the load switch maintains a conductive state during charging.

When the power receiving module 300 is charged each time, the first electronic switch tube Qboost is conducted to charge the inductor L for a plurality of times, after each charging, a discharging switch is turned on, so that each discharging switch and the power receiving module 300 are sequentially discharged, and after each discharging period is finished, the next cycle of charging period is started.

Example III

Based on the embodiment one, as shown in fig. 8, in another alternative embodiment, the charging energy storage circuit 10 includes a second electronic switching tube qbuck_h, a third electronic switching tube qbuck_l, and an inductor L, where a first end of the second electronic switching tube qbuck_h forms an input end of the charging energy storage circuit 10, a second end of the second electronic switching tube qbuck_h, a first end of the third electronic switching tube qbuck_l are connected to a first end of the inductor L, a second end of the third electronic switching tube qbuck_l is grounded, and a second end of the inductor L forms an output end of the charging energy storage circuit 10.

In this embodiment, a plurality of discharge switches, a second electronic switching tube qbuck_h, a third electronic switching tube qbuck_l and an inductor L form a single-input multi-output buck conversion circuit, the plurality of discharge switches time-division multiplex the second electronic switching tube qbuck_h and the third electronic switching tube qbuck_l, and a load switch maintains a conducting state in a charging process.

During each charging, the second electronic switching tubes qbuck_h and the third electronic switching tubes qbuck_l are turned on and off according to the received PWM modulation signals, and charge the inductor L, the second electronic switching tubes qbuck_h and the third electronic switching tubes qbuck_l are multiplexed by the plurality of discharging switches in a time-sharing manner, and each time the power receiving module 300 is charged, the second electronic switching tubes qbuck_h and the discharging switches are conducted to charge the inductor L for a plurality of times, and after each charging, the third electronic switching tubes qbuck_l and the discharging switch are turned on, so that each discharging switch and the power receiving module 300 are sequentially discharged, and after each discharging period is finished, the next cycle charging period is entered.

Example IV

In another alternative embodiment, as shown in fig. 9, the charging energy storage circuit 10 includes a first electronic switch tube Qboost, a second electronic switch tube qbuck_h, a third electronic switch tube qbuck_l and an inductor L, wherein a first end of the second electronic switch tube qbuck_h forms an input end of the charging energy storage circuit 10, a second end of the second electronic switch tube qbuck_h, a first end of the third electronic switch tube qbuck_l is connected with a first end of the inductor L, a second end of the third electronic switch tube qbuck_l is grounded, a second end of the inductor L and a first end of the first electronic switch tube Qboost are connected to form an output end of the charging energy storage circuit 10, and a second end of the first electronic switch tube Qboost is grounded.

In this embodiment, a plurality of discharge switches, a first electronic switching tube Qboost, a second electronic switching tube qbuck_h, a third electronic switching tube qbuck_l and an inductor L form a single-input multi-output buck-boost conversion circuit, and a load switch maintains a conducting state in a charging process.

When in the boost mode, the plurality of discharging switches time-division multiplex the first electronic switch tube Qboost, and each time the charging is performed, the first electronic switch tube Qboost is switched on and off according to the received PWM modulation signal and charges the inductor L, the plurality of discharging switches time-division multiplex the first electronic switch tube Qboost, each time the power receiving module 300 is charged, the first electronic switch tube Qboost is conducted to charge the inductor L for a plurality of times, after each charging is finished, a discharging switch is turned on, thereby realizing the sequential discharging of each discharging switch and the power receiving module 300, and after each discharging period is finished, the next cycle charging period is entered.

When in the boost mode, the plurality of discharge switches time-division multiplex the second electronic switching tube qbuck_h and the third electronic switching tube qbuck_l, and each time the second electronic switching tube qbuck_h and the third electronic switching tube qbuck_l are charged according to the received PWM modulation signal, and charge the inductor L, the plurality of discharge switches time-division multiplex the second electronic switching tube qbuck_h and the third electronic switching tube qbuck_l, each time the power receiving module 300 is charged, the second electronic switching tube qbuck_h and the discharge switch are conducted to the inductor L for a plurality of times, and after each time charging is finished, the third electronic switching tube qbuck_l and a discharge switch are turned on, so that each discharge switch and the power receiving module 300 are sequentially discharged, and after each discharge period is finished, the next cycle charging period is entered.

The discharging switch can adopt a corresponding structure switch structure, such as a relay, a triode, a MOS tube and the like.

Further, in order to avoid crosstalk between the electrical modules 300, the discharge switch may adopt a substrate switching structure or a power tube back-to-back connection, so as to realize isolation between different paths.

As shown in fig. 10, in an alternative embodiment, the discharge switch includes a first PMOS transistor and a second PMOS transistor, for example, a first PMOS transistor q1_p1 and a second PMOS transistor q1_p2 of the first discharge switch q1_1, or a first PMOS transistor q2_p1 and a second PMOS transistor q2_p2 of the second discharge switch q1_2;

the drain electrode of the first PMOS tube forms a first end of the discharge switch, the source electrode of the first PMOS tube is connected with the source electrode of the second PMOS tube, the drain electrode of the second PMOS tube forms a second end of the discharge switch, and the grid electrodes of the first PMOS tube and the second PMOS tube are respectively connected with the signal end of the constant current control circuit 40;

and the second PMOS tube of the ith discharging switch triggers to be conducted in dead time before the ith discharging switch to be conducted is conducted, so that residual charges of the inductor L are released in a follow current mode.

In this embodiment, two PMOS transistors in the discharge switch are connected back to back, when one of the two paths needs to be discharged, the gate voltages of the first PMOS transistor and the second PMOS transistor are pulled down, the first PMOS transistor and the second PMOS transistor are turned on, the inductance L current in the charge energy storage circuit 10 charges the capacitor, at this time, the first PMOS transistor and the second PMOS transistor of the discharge circuit 20 of the other path are pulled up, the other discharge circuits 20 are turned off, and the path crosstalk is prevented from occurring between the discharge circuits 20 of the other paths.

Meanwhile, when all the discharging switches are in an off state, i.e. dead time, the constant current control circuit 40 needs to reserve an inductance L current freewheeling path to carry out freewheeling and discharging on residual charges of the inductance L, for example, VOUT1 is being charged, at this time, the constant current control circuit 40 pulls down the gate of the second PMOS tube corresponding to VOUT1, the inductance L current is freewheeling normally, and when the discharging switches need to be fully turned on, the constant current control circuit 40 pulls down the gate of the first PMOS tube corresponding to VOUT 1.

Similarly, when VOUT2 is being charged, at this time, the constant current control circuit 40 pulls down the gate voltage of the second PMOS transistor corresponding to VOUT2, the inductor L current flows normally, and when the discharge switch needs to be fully turned on, the constant current control circuit 40 pulls down the gate of the first PMOS transistor corresponding to VOUT 2.

In another alternative embodiment, the discharge switch employs a switched substrate connection method, alternatively, as shown in fig. 11, the discharge switch includes a transistor employing a switched substrate connection method, a first diode D1, a first switch S1, a second diode D2, and a second switch S2, for example, the first discharge switch q1_1 includes a first transistor Q11, a first diode D1, a first switch S1, a second diode D2, and a second switch S2, or the second discharge switch q1_2 includes a second stage transistor Q12, a first diode D1, a first switch S1, a second diode D2, and a second switch S2, and the like.

The anode of the first diode D1, the first end of the second switch S2 and the second end of the transistor are connected to form a second end of the discharge switch, the anode of the second diode D2, the first end of the first switch S1 and the first end of the transistor are connected to form a first end of the discharge switch, the cathode of the first diode D1 is connected with the second end of the first switch S1, and the cathode of the second diode D2 is connected with the second end of the second switch S2;

when the grid electrode of the transistor receives a low level, the second switch S2 is triggered to be turned on, and the first switch S1 is triggered to be turned off;

and when the grid electrode of the transistor receives a high level, the second switch S2 triggers to conduct when the output end voltage of the transistor is larger than the input end voltage, and the first switch S1 triggers to conduct when the output end voltage of the transistor is smaller than or equal to the input end voltage.

In this embodiment, when the discharge switch corresponding to VOUT1 needs to be discharged, the gate voltage of the transistor of the discharge switch is pulled down, the second switch S2 of the circuit is turned on, and the gate of the transistor corresponding to VOUT2 is pulled up, but the substrate connection method of the transistor of the circuit is limited by the condition:

if the voltage of VOUT2 is greater than the voltage of VOUT1 at this time, the second switch S2 corresponding to VOUT2 is turned on, and the first diode D1 corresponding to VOUT2 is turned off reversely, so as to prevent VOUT2 from charging VOUT 1.

If the voltage of VOUT1 is greater than VOUT2 at this time, the first switch S1 corresponding to VOUT2 is turned on, and the second diode D2 corresponding to VOUT2 is turned off reversely, so as to prevent VOUT1 from charging VOUT 2.

Similarly, when the discharge switch corresponding to VOUT2 needs to be discharged, the gate voltage of the transistor of the discharge switch is pulled down, the second switch S2 of the circuit is turned on, and the gate of the transistor corresponding to VOUT1 is pulled up, but the substrate connection method of the transistor of the circuit is limited by the condition:

if the voltage of VOUT1 is greater than the voltage of VOUT2 at this time, the second switch S2 corresponding to VOUT1 is turned on, and the first diode D1 corresponding to VOUT1 is turned off reversely, so as to prevent VOUT1 from charging VOUT 2.

If the voltage of VOUT2 is greater than VOUT1 at this time, the first switch S1 corresponding to VOUT1 is turned on, and the second diode D2 corresponding to VOUT1 is turned off reversely, so as to prevent VOUT2 from charging VOUT 1.

And the whole loop control is realized by circulating in this way.

Example five

The implementation and optimization are performed on the basis of the first embodiment, and as shown in fig. 12, optionally, the single-input multiple-output charging circuit 100 further includes:

the second sampling circuit 50 is respectively connected with the charging energy storage circuit 10 and the constant current control circuit 40, and the second sampling circuit 50 is used for sampling the charging current of the charging energy storage circuit 10 and outputting a second sampling signal to the constant current control circuit 40;

The constant current control circuit 40 includes:

the comparison trigger circuits 41 are respectively connected with the first sampling circuit 30 and the second sampling circuit 50, the comparison trigger circuits 41 also receive a clock signal with a corresponding phase, and the comparison trigger circuits 41 are used for determining the duty ratio of the PWM modulation signal when the charging energy storage circuit 10 is charged for the ith time in each cycle according to the average output current, the output voltage, the preset average output current, the preset output voltage and the charging current of the ith discharging circuit 20 to be discharged, and determining the output moment of the PWM modulation signal according to the high-level pulse of the clock signal;

the logic control circuit 42 is connected with the comparison trigger circuits 41, the charging energy storage circuits 10 and the discharging circuits 20 respectively, and the logic control circuit 42 is used for receiving a plurality of PWM modulation signals and outputting the PWM modulation signals and the switching signals according to corresponding time sequences so as to perform constant-current charging control on the power receiving modules 300;

the clock signals received by the comparison trigger circuits 41 are respectively different from each other by a preset phase.

In this embodiment, referring to fig. 3, it is assumed that the power receiving modules 300 include two power receiving modules, the clock signal received by the comparison triggering circuit 41 corresponding to the first power receiving module 300 is CLK1, the clock signal received by the comparison triggering circuit 41 corresponding to the second power receiving module 300 is CLK2, the average output current of the first discharging circuit 20 connected to the first power receiving module 300 is IOUT1, the output voltage is VOUT1, the preset average output current corresponding to the first power receiving module 300 is Iref1, the preset output voltage is Vref1, the average output current of the second discharging circuit 20 connected to the second power receiving module 300 is IOUT2, the output voltage is VOUT2, the preset average output current corresponding to the second power receiving module 300 is Iref2, the preset output voltage is Vref2, wherein VEA1 is the preset peak current of the energy storage circuit 10 corresponding to the preset average output current Iref1 of the first discharging circuit 20 and the preset output voltage Vref1, VEA2 is the preset peak current of the energy storage circuit 10 corresponding to the preset peak current of the preset charging circuit 10.

When CLK1 is output as a high level pulse signal, the comparison triggering circuit 41 outputs a PWM modulation signal to the logic control circuit 42, the logic control circuit 42 outputs the PWM modulation signal to the charge energy storage circuit 10, the charge energy storage circuit 10 starts charging and storing energy, when the peak current of the charge energy storage circuit 10 reaches VEA1, the logic control circuit 42 controls the charge energy storage circuit 10 to turn off and controls the first discharging circuit 20 to turn on, the charge energy storage circuit 10 discharges to the first power receiving module 300 through the first discharging circuit 20, when the current of the charge energy storage circuit 10 drops to zero, the logic control circuit 42 outputs a switching signal to control the first discharging circuit 20 to turn off, the energy output of VOUT1 path is finished, during discharging, the comparison triggering circuit 41 samples the average output current and the output voltage of the first discharging circuit 20 through the first sampling circuit 30, and compares the average output current and the preset output voltage with the charge current of the charge energy storage circuit 10 respectively, and determines the duty ratio of the PWM modulation signal required by the charge energy storage circuit 10 before the first discharging circuit 20 is correspondingly discharged, and thus the cycle of the next charge energy storage circuit 10 is changed.

When the first discharging circuit 20 is turned off, CLK2 is switched to a high level pulse signal, the comparison triggering circuit 41 outputs another PWM modulation signal to the logic control circuit 42, the logic control circuit 42 outputs the PWM modulation signal to the charging energy storage circuit 10, the charging energy storage circuit 10 charges and stores energy again, when the peak current of the charging energy storage circuit 10 reaches VEA2, the logic control circuit 42 controls the charging energy storage circuit 10 to turn off and controls the second discharging circuit 20 to turn on, the charging energy storage circuit 10 discharges to the second power receiving module 300 through the second discharging circuit 20, when the current of the charging energy storage circuit 10 drops to zero, the logic control circuit 42 outputs a switching signal to control the second discharging circuit 20 to turn off, the energy output of the VOUT2 path is finished, during discharging, the comparison triggering circuit 41 samples the average output current and the output voltage of the second discharging circuit 20 through the first sampling circuit 30, compares the comparison result with the matched preset average output current and preset output voltage, and determines the charging current of the charging energy storage circuit 10, and changes the duty ratio of the charging energy storage circuit 10 when the charging energy storage circuit 10 is charged and the required for the PWM modulation signal is changed once according to the comparison result.

When the second discharging circuit 20 is turned off, CLK1 is switched to the high level pulse signal again, the comparison triggering circuit 41 outputs the adjusted PWM modulation signal to the logic control circuit 42 and to the charging energy storage circuit 10 through the logic control circuit 42, the charging energy storage circuit 10 performs charging and discharging again, and the first discharging circuit 20 discharges to the first power receiving module 300 again, thereby realizing constant current output control of the first power receiving module 300.

Similarly, when the first discharging circuit 20 is turned off again, CLK2 is switched to the high level pulse signal again, the comparison triggering circuit 41 outputs the adjusted PWM modulation signal to the logic control circuit 42 and to the charging energy storage circuit 10 through the logic control circuit 42, the charging energy storage circuit 10 charges and discharges again, and discharges again to the second power receiving module 300 through the second discharging circuit 20, thereby realizing constant current output control of the second power receiving module 300.

The logic control circuit 42 may adopt a corresponding structure such as a processor, a controller, etc., and the specific structure is not limited.

The comparison trigger circuit 41 may adopt a plurality of structures of a comparison circuit, a trigger circuit, and the like, and alternatively, as shown in fig. 13, the comparison trigger circuit 41 includes a voltage error amplifier EA1V, a current error amplifier EA1A, a compensation circuit 411, a first comparator CMP1, and a trigger U1;

the positive input end of the voltage error amplifier EA1V is used for inputting preset output voltage, the negative input end of the voltage error amplifier EA1V is used for inputting sampling value of output voltage, the positive input end of the current error amplifier EA1A is used for inputting preset average output current, the negative input end of the current error amplifier EA1A is used for inputting sampling value of average output current, the output end of the voltage error amplifier EA1V, the output end of the current error amplifier EA1A, the output end of the compensation circuit 411 and the positive input end of the first comparator CMP1 are connected, the negative input end of the first comparator CMP1 is used for inputting sampling value of charging current, the output end of the first comparator CMP1 is connected with the reset end of the trigger U1, and the set end of the trigger U1 is used for inputting clock signal.

In the present embodiment, each comparison trigger circuit 41 is composed of a voltage error amplifier EA1V, a current error amplifier EA1A, a compensation circuit 411, a first comparator CMP1 and a trigger U1.

Referring to fig. 3 and 7, it is assumed that the power receiving module 300 includes two voltage error comparators that clamp the highest voltage of VOUT1 or VOUT2 (clamp voltages Vref1 and Vref2, respectively) after the power receiving module 300 charges into the constant voltage phase to improve the charging efficiency.

The current error amplifier EA1A will ensure that the average output current value IOUT1 or IOUT2 is entirely determined by the internal reference current Iref1/Iref 2.

The compensation circuit 411 is configured to perform current compensation on the comparison value output by the voltage error amplifier EA1V and/or the current error amplifier EA1A, compare the comparison value after current compensation with the inductor L current, and output the comparison value to the trigger U1, where the trigger U1 determines, according to the clock signal and the comparison result, the timing and the duty ratio of the PWM modulation signal of the first electronic switching tube Qboost, and the timing of the PWM modulation signal output to the discharge module and the switching signal.

The clock signal received by the comparison triggering circuit 41 corresponding to the first power receiving module 300 is CLK1, the clock signal received by the comparison triggering circuit 41 corresponding to the second power receiving module 300 is CLK2, the average output current of the first discharging circuit 20 connected with the first power receiving module 300 is IOUT1, the output voltage is VOUT1, the preset average output current corresponding to the first power receiving module 300 is Iref1, the preset output voltage is Vref1, the average output current of the second discharging circuit 20 connected with the second power receiving module 300 is IOUT2, the output voltage is VOUT2, the preset average output current corresponding to the second power receiving module 300 is Iref2, the preset output voltage is Vref2, wherein VEA1 is the preset peak current of the charging energy storage circuit 10 corresponding to the preset average output current Iref1 and the preset output voltage Vref1 of the first discharging circuit 20, VEA2 is the preset peak current of the charging energy storage circuit 10 corresponding to the average output current Iref2 and the preset output voltage Vref2 of the second discharging circuit 20, and IL is the preset peak current of the charging energy storage circuit 10.

When CLK1 is output as a high level pulse signal, the trigger U1 outputs a PWM modulation signal to the logic control circuit 42, the logic control circuit 42 outputs a PWM modulation signal to the charge energy storage circuit 10, the charge energy storage circuit 10 starts charging energy storage, when the peak current of the charge energy storage circuit 10 reaches VEA1, i.e. when the first comparator CMP1 is turned over, the logic control circuit 42 controls the charge energy storage circuit 10 to turn off and controls the first discharging circuit 20 to turn on, the charge energy storage circuit 10 discharges to the first power receiving module 300 through the first discharging circuit 20, when the inductance L current drops to zero, the logic control circuit 42 outputs a switching signal to control the first discharging circuit 20 to turn off, the energy output of the VOUT1 path is finished, during discharging, the comparison triggering circuit 41 samples the average output current and the output voltage of the first discharging circuit 20 through the first sampling circuit 30, and compares the comparison result with the preset average output current and the preset output voltage through the current error amplifier EA1A and the voltage error amplifier EA1V, respectively, the comparison result is compensated and compared with the charge current of the charge energy storage circuit 10, and the duty ratio of the charge energy storage circuit 10 is changed when the charge energy storage circuit 10 is charged and the charge cycle ratio of the first discharging circuit is determined.

When the first discharging circuit 20 is turned off, CLK2 is switched to a high level pulse signal, the trigger U1 outputs another PWM modulation signal to the logic control circuit 42, the logic control circuit 42 outputs the PWM modulation signal to the charging energy storage circuit 10, the charging energy storage circuit 10 charges and stores energy again, when the peak current of the charging energy storage circuit 10 reaches VEA2, the first comparator CMP1 turns over, the logic control circuit 42 controls the charging energy storage circuit 10 to turn off and controls the second discharging circuit 20 to turn on, the charging energy storage circuit 10 discharges to the second power receiving module 300 through the second discharging circuit 20, when the current of the charging energy storage circuit 10 drops to zero, the logic control circuit 42 outputs a switching signal to control the second discharging circuit 20 to turn off, and the energy output of the VOUT2 path is finished, in the discharging process, the comparison trigger circuit 41 samples the average output current and the output voltage of the second discharging circuit 20 through the first sampling circuit 30, and compares the average output current and the preset output voltage with the matched preset average output current and the preset output voltage through the current error amplifier EA1A and the voltage error amplifier EA1V respectively, the comparison result is compared with the charging current of the charging energy storage circuit 10 after current compensation, and the duty ratio of the PWM modulation signal required by the charging energy storage circuit 10 before the second discharging circuit 20 corresponds to the discharging is determined according to the comparison result, so that the charging electric energy of the charging energy storage circuit 10 in the next cycle charging is changed.

When the second discharging circuit 20 is turned off, CLK1 is switched to the high level pulse signal again, the trigger U1 outputs the adjusted PWM modulation signal to the logic control circuit 42 and to the charge energy storage circuit 10 through the logic control circuit 42, the charge energy storage circuit 10 performs charging and discharging again, and discharges to the first power receiving module 300 again through the first discharging circuit 20, thereby realizing constant current output control of the first power receiving module 300.

Similarly, after the first discharging circuit 20 is turned off again, CLK2 is switched to the high level pulse signal again, the trigger U1 outputs the adjusted PWM modulation signal to the logic control circuit 42 and to the charge energy storage circuit 10 through the logic control circuit 42, the charge energy storage circuit 10 charges and discharges again, and discharges again to the second power receiving module 300 through the second discharging circuit 20, thereby realizing constant current output control of the second power receiving module 300.

Example six

Based on the optimization and refinement of the first embodiment, in order to reduce the no-load output and improve the charging efficiency, as shown in fig. 14, the single-input multiple-output charging circuit 100 further includes:

a plurality of access detection and communication circuits 70, wherein an access detection and communication circuit 70 is respectively connected with a discharging circuit 20 and the constant current control circuit 40, and the access detection and communication circuit 70 is used for:

Detecting the in-out bin state of the power receiving module 300 and outputting an in-out bin detection signal to the constant current control circuit 40;

two-way communication between power module 200 and power receiving module 300 is established.

In this embodiment, the in-out detection and communication circuit 70 is further connected to the power supply module 200 and the power receiving module 300, and by setting a plurality of in-out detection and communication circuits 70, the connection state of each power receiving module 300 can be determined, so that in the cyclic charging process, selective charging can be performed, no-load output is reduced, and charging efficiency is improved.

Meanwhile, by establishing the bidirectional communication between the power supply module 200 and the power receiving module 300, the working states of the power supply module 200 and the power receiving module 300 can be determined, and then the charging mode is adjusted according to the working states, for example, when one of the power receiving modules 300 is abnormal or needs to suspend charging, the power supply module 200 cuts off the output power supply or controls the charging circuit 100 to cut off the discharging circuit 20 corresponding to the power receiving module 300, skips the power receiving module 300, charges other power receiving modules 300, and sets the discharging circuit 20 and the power receiving module 300 into the charging queue again when the normal state is restored.

Meanwhile, through the integrated in-out bin detection and communication, the overall structure of the charging circuit 100 is simplified, and the overall structure of the wearable device is further simplified.

The in-out detection and communication circuit 70 may adopt a corresponding switch loop structure, as shown in fig. 15, optionally, the in-out detection and communication circuit 70 includes a fourth electronic switch tube QH2, a fifth electronic switch tube QH1, a sixth electronic switch tube QL1, a current source I1 and a third comparator CMP3;

the first end of the fourth electronic switching tube QH2, the positive phase input end of the third comparator CMP3 and the positive charging interface are connected, the second end of the fourth electronic switching tube QH2 and the first end of the fifth electronic switching tube QH1 are connected and connected with the positive power supply end VCC, the second end of the fifth electronic switching tube QH1, the first end of the sixth electronic switching tube QL1, the output end of the current source I1, the inverting input end of the third comparator CMP3 and the negative charging interface are connected, the second end of the sixth electronic switching tube QL1 is grounded, and the output end of the comparator forms the signal output end of the access bin detection and communication circuit 70.

In this embodiment, the load switch remains off during the detection and communication of the access chamber.

When the bin is detected, the fourth electronic switching tube QH2 is controlled to be turned on, the fifth electronic switching tube QH1 and the sixth electronic switching tube QL1 are controlled to be turned off, when the power receiving module 300 is not reliably connected or inserted, the voltage of the positive input end of the third comparator CMP3 is larger than the voltage of the negative input end, the third comparator CMP3 outputs a high level, when the power receiving module 300 is reliably connected or inserted, the third comparator CMP3 outputs a low level, and the constant current control circuit 40 can determine the connection state of the current power receiving module 300 according to the received high and low levels.

When the power supply module 200 sends a signal to the power receiving module 300, the fourth electronic switching tube QH2 is turned on, the fifth electronic switching tube QH1 and the sixth electronic switching tube QL1 are correspondingly triggered to be turned on and off according to the format of the communication data, the level of the connection node of the fifth electronic switching tube QH1 and the sixth electronic switching tube QL1 is changed, the positive charging interface and the negative charging interface output changed level signals and are transmitted to the power receiving module 300, and the power receiving module 300 determines the communication information according to the changed level signals.

When the power receiving module 300 sends a signal to the power supplying module 200, the fourth electronic switching tube QH2, the fifth electronic switching tube QH1 and the sixth electronic switching tube QL1 are controlled to be turned off, and the communication signal of the power receiving module 300 is transmitted to the power supplying module 200 through the third comparator CMP 3.

Example seven

As shown in fig. 16, the present application further provides a wearable device, where the wearable device includes a power supply module 200, a plurality of power receiving modules 300, and a single-input-multiple-output charging circuit 100, and the specific structure of the single-input-multiple-output charging circuit 100 refers to the foregoing embodiments. The single-input multi-output charging circuit 100 is used for connecting the power supply module 200 and the plurality of power receiving modules 300 and performing charging and discharging operations.

In this embodiment, the power supply module 200 performs cyclic charging on the plurality of power receiving modules 300 through the charging circuit 100 for multiple times, and adjusts charging and discharging electric energy in the charging process, so as to adjust current and voltage output to each power receiving module 300, thereby realizing constant current charging and subsequent constant voltage charging, and improving charging efficiency.

The wearable device may be a TWS earphone, a wireless microphone, an intelligent glasses, or the like, for example, when the wearable device is a TWS earphone, a battery BAT1 bin of the TWS earphone is a power supply module 200, meanwhile, a charging circuit 100 is disposed in the battery BAT1 bin, an earphone component of the TWS earphone is a power receiving module 300, and when the wearable device is charged, the earphone component is disposed in the earphone bin and is correspondingly connected with a PIN or a contact in the battery BAT1 bin through the PIN or the contact for charging, and at this time, the power receiving module 300 includes two components.

The above embodiments are only for illustrating the technical solution of the present application, and are not limiting; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present application, and are intended to be included in the scope of the present application.

Claims

1. A single-input multiple-output charging circuit, comprising:

determining the duty ratio of a PWM modulation signal in the ith charging of the charging energy storage circuit in the next cycle period according to the average output current, the output voltage, the preset average output current and the preset output voltage of the ith discharging circuit so as to perform constant-current charging control on each power receiving module, wherein i=1, 2..n, n is the number of the discharging circuits to be discharged;

the single-input multiple-output charging circuit further includes:

the constant current control circuit includes:

2. The single-input multiple-output charging circuit of claim 1, wherein the charging energy storage circuit comprises a first electronic switching tube and an inductor;

3. The single-input multiple-output charging circuit of claim 1, wherein the charging energy storage circuit comprises a second electronic switching tube, a third electronic switching tube, and an inductor;

4. The single-input multiple-output charging circuit of claim 1, wherein the charging energy storage circuit comprises a first electronic switching tube, a second electronic switching tube, a third electronic switching tube, and an inductor;

5. The single-input multiple-output charging circuit according to any one of claims 2 to 4, wherein the discharging circuit includes a discharging switch and a capacitor;

6. The single-input multiple-output charging circuit of claim 5, wherein the discharge switch comprises a first PMOS tube and a second PMOS tube;

7. The single input multiple output (mimo) charging circuit of claim 5, wherein the discharge switch comprises a transistor employing a switched substrate connection, a first diode, a first switch, a second diode, and a second switch;

8. The single-input multiple-output charging circuit of claim 7, wherein the comparison triggering circuit comprises a voltage error amplifier, a current error amplifier, a compensation circuit, a first comparator, and a flip-flop;

9. The single-input multiple-output charging circuit of claim 1, wherein the single-input multiple-output charging circuit further comprises:

10. The single-input multiple-output charging circuit of claim 9, wherein the full power detection circuit comprises a current transformer and a second comparator;

11. The single-input multiple-output charging circuit of claim 1, wherein the single-input multiple-output charging circuit further comprises:

12. The single-input multiple-output (mimo) charging circuit of claim 11, further comprising a plurality of charging interfaces and load switches for one-to-one connection with a plurality of power receiving modules, respectively, each of the charging interfaces comprising a positive charging interface and a negative charging interface, the load switches being connected in series between the negative charging interface and ground, the output of the discharging circuit being connected to the positive charging interface;

13. The wearable device is characterized by comprising a power supply module, a plurality of power receiving modules and the single-input multi-output charging circuit according to any one of claims 1-12, wherein the single-input multi-output charging circuit is used for connecting the power supply module and the power receiving modules and performing charging and discharging operations.