Granted Patent B2

US 12,640,577 · App. 17/829,394 · Granted May 26, 2026

Inventors: Wei-Hsu Chang (Hsinchu, TW); Ta-Yung Yang (Taoyuan, TW)

Assignee: RICHTEK TECHNOLOGY CORPORATION

H02J7/00712H02M1/0009H02M1/0012H02J2207/20

Abstract

Claims (67)

1 . A charging control method configured to control a charging system, comprising:

converting an input power to a DC power;

receiving the DC power via a detachable cable, so as to generate a bus power; and

converting the bus power to a charging power configured to charge a battery in a charging period;

wherein the step of converting the bus power to the charging power includes:

based on a relationship between the DC power and the charging power, operating an inductive switching power converter to selectively either convert the bus power into a first power in a first regulation mode or bypass the bus power into the first power in a first short circuit conduction mode; and

based on the relationship between the DC power and the charging power, operating a capacitive switching power converter to selectively either convert the first power into the charging power in a second regulation mode or bypass the first power into the charging power in a second short circuit conduction mode;

wherein the step of converting the input power to the DC power includes:

adaptively adjusting the DC power based on power conversion efficiency feedback to track a maximum power conversion efficiency of the charging system, in combination with selectively operating the inductive switching power converter in either the first regulation mode or the first short circuit conduction mode, and operating the capacitive switching power converter in either the second regulation mode or the second short circuit conduction mode, based on the DC power and the charging power.

2 . The charging control method of claim 1 , wherein the step of adjusting the DC power to track the maximum power conversion efficiency includes the following steps:

S 11 : obtaining a power conversion efficiency according to the DC power;

S 12 : subsequent to the step S 11 , positively or negatively adjusting the DC power;

S 13 : obtaining an adjusted power conversion efficiency according to the adjusted DC power;

S 14 : subsequent to the step S 13 , comparing the adjusted power conversion efficiency with the power conversion efficiency before adjustment;

S 15 : subsequent to the step S 14 , when the adjusted power conversion efficiency is higher than the power conversion efficiency before adjustment, adjusting the DC power in a same manner as the step S 12 and executing the step S 13 ; and

S 16 : subsequent to the step S 14 , when the adjusted power conversion efficiency is not higher than the power conversion efficiency before adjustment, adjusting the DC power in an opposite manner as the step S 12 and executing the step S 13 .

3 . The charging control method of claim 1 , wherein the DC power includes a DC voltage and/or a DC current.

4 . The charging control method of claim 1 , wherein during the charging period, a charging voltage and/or a charging current of the charging power is constant.

5 . The charging control method of claim 1 , wherein the input power includes an input voltage and an input current, wherein the input voltage is constant; wherein the step of adjusting the DC power includes adjusting the DC power to track a minimum of the input current, so as to track the maximum power conversion efficiency.

6 . The charging control method of claim 1 , wherein the input power includes an input voltage and an input current; wherein the input voltage and/or the input current is detected and obtained by an analog digital conversion (ADC) circuit or wherein the input voltage and/or the input current is detected and obtained according to a DC voltage of the DC power and a look up table.

7 . The charging control method of claim 1 , wherein the step of converting the bus power to the charging power is achieved by one of the following:

when a bus voltage of the bus power is lower than a first threshold, operating the inductive switching power converter in the first regulation mode, wherein the first threshold is correlated with a charging voltage of the charging power;

when the bus voltage of the bus power is lower than a second threshold, operating the capacitive switching power converter in the second short circuit conduction mode, wherein the second threshold is correlated with a product of the charging voltage multiplied by a current magnification ratio, wherein the current magnification ratio is a ratio of a charging current of the charging power to a first current of the first power;

when a bus current of the bus power is constant, operating the inductive switching power converter in the first short circuit conduction mode;

when the bus current of the bus power is constant, and when the bus voltage is variable and exceeds the second threshold, operating the inductive switching power converter in the first short circuit conduction mode and operating the capacitive switching power converter in the second regulation mode.

8 . A charging system, comprising:

a power delivery unit, which is configured to operably convert an input power to a DC power;

a detachable cable, which is configured to operably receive the DC power, and generate a bus power; and

a charging circuit, which is configured to operably convert the bus power to a charging power to charge a battery in a charging period;

wherein the charging circuit includes an inductive switching power converter and a capacitive switching power converter, wherein the inductive switching power converter is configured to convert the bus power into a first power, and the capacitive switching power converter is configured to convert the first power into the charging power;

wherein based on a relationship between the DC power and the charging power, the inductive switching power converter is configured to selectively operate in either a first regulation mode or a first short circuit conduction mode, and the capacitive switching power converter is configured to selectively operate in either a second regulation mode or a second short circuit conduction mode; wherein

in the first regulation mode, the inductive switching power converter regulates the first power to a predetermined target;

in the second regulation mode, the capacitive switching power converter regulates the charging power to a predetermined target;

in the first short circuit conduction mode, the inductive switching power converter short-circuits the bus power to the first power; and

in the second short circuit conduction mode, the capacitive switching power converter short-circuits the first power to the charging power;

wherein the power delivery unit is configured to adaptively adjust the DC power based on power conversion efficiency feedback to track a maximum power conversion efficiency of the charging system, in combination with selectively operating the inductive switching power converter in either the first regulation mode or the first short circuit conduction mode, and operating the capacitive switching power converter in either the second regulation mode or the second short circuit conduction mode, based on the DC power and the charging power.

9 . The charging system of claim 8 , wherein the power delivery unit is configured to adjust the DC power so as to track the maximum power conversion efficiency by steps including:

S 11 : obtaining a power conversion efficiency according to the DC power;

S 12 : subsequent to the step S 11 , positively or negatively adjusting the DC power;

S 13 : obtaining an adjusted power conversion efficiency according to the adjusted DC power;

S 14 : subsequent to the step S 13 , comparing the adjusted power conversion efficiency with the power conversion efficiency before adjustment;

S 15 : subsequent to the step S 14 , when the adjusted power conversion efficiency is higher than the power conversion efficiency before adjustment, adjusting the DC power in a same manner as the step S 12 and executing the step S 13 ; and

S 16 : subsequent to the step S 14 , when the adjusted power conversion efficiency is not higher than the power conversion efficiency before adjustment, adjusting the DC power in an opposite manner as the step S 12 and executing the step S 13 .

10 . The charging system of claim 8 , wherein the DC power includes a DC voltage and/or a DC current.

11 . The charging system of claim 8 , wherein during the charging period, a charging voltage and/or a charging current of the charging power is constant.

12 . The charging system of claim 10 , wherein the input power includes an input voltage and an input current, wherein the input voltage is constant; wherein the DC power is adjusted to track a minimum of the input current, so as to track the maximum power conversion efficiency.

13 . The charging system of claim 9 , wherein the detachable cable includes:

a power line, which is configured to operably receive the DC power, so as to generate the bus power; and

a communication bus coupled between the power delivery unit and the charging circuit, wherein the communication bus is configured to operably transmit a signal related to the DC power, a signal related to the bus power and/or a signal related to the charging power.

14 . The charging system of claim 13 , further comprising:

a tracking control circuit, which is coupled between the power delivery unit and the charging circuit and which is configured to operably generate a communication signal according to the power conversion efficiency, wherein the communication signal is transmitted to the power delivery unit via the communication bus, for adjusting the DC power to track the maximum power conversion efficiency.

15 . The charging system of claim 8 , wherein the power delivery unit detects and obtains an input voltage and an input current of the input power by an analog digital conversion (ADC) circuit in the power delivery unit; or, wherein the power delivery unit detects and obtains the input voltage and the input current of the input power according to a DC voltage of the DC power and a look up table.

16 . The charging system of claim 8 , wherein:

the inductive switching power converter includes a plurality of first switching devices, which are configured to operably switch a coupling relationship between an inductor and the bus power and a coupling relationship between the inductor and the first power, so as to convert the bus power to the first power; and

the capacitive switching power converter includes a plurality of second switching devices, which are configured to operably switch a coupling relationship between a conversion capacitor and the first power and a coupling relationship between the conversion capacitor and the charging power, so as to convert the first power to the charging power;

wherein in the first regulation mode, the plurality of the first switching devices are configured to switch the inductor, so as to regulate the first power to a first predetermined target, and wherein in the first short circuit conduction mode, at least one of the plurality of first switching devices is controlled to be conductive, so as to short-circuit the bus power to the first power, wherein the at least one of the plurality of the first switching devices switches periodically in the first regulation mode;

wherein in the second regulation mode, the plurality of the second switching devices are configured to switch the conversion capacitor, so as to regulate the charging power to a second predetermined target, and wherein in the second short circuit conduction mode, at least one of the plurality of the second switching devices is controlled to be conductive, so as to short-circuit the first power to the charging power, wherein the at least one of the plurality of the second switching devices switches periodically in the second regulation mode.

17 . The charging system of claim 16 , wherein:

when a bus voltage of the bus power is lower than a first threshold, the inductive switching power converter operates in the first regulation mode, wherein the first threshold is correlated with a charging voltage of the charging power;

when the bus voltage of the bus power is lower than a second threshold, the capacitive switching power converter operates in the second short circuit conduction mode, wherein the second threshold is correlated with a product of the charging voltage multiplied by a current magnification ratio, wherein the current magnification ratio is a ratio of a charging current of the charging power to a first current of the first power;

when a bus current of the bus power is constant, the inductive switching power converter operates in the first short circuit conduction mode;

when the bus current of the bus power is constant, and when the bus voltage is variable and exceeds the second threshold, the inductive switching power converter operates in the first short circuit conduction mode and the capacitive switching power converter operates in the second regulation mode.

18 . The charging system of claim 8 , wherein the power delivery unit includes an AC-DC power converter or a DC-DC power converter.

19 . The charging system of claim 8 , wherein the power delivery unit includes a universal serial bus (USB) power delivery (PD) circuit.

20 . The charging system of claim 8 , wherein the capacitive switching power converter is a capacitor voltage divider.

21 . The charging system of claim 17 , wherein the inductive switching power converter is a buck switching power converter, and wherein when the DC power is programmable and is lower than the first threshold, an upper gate switch of the plurality of the first switching devices is fully conductive, so as to short-circuit the DC power and the first power.

22 . The charging system of claim 17 , wherein the first threshold is higher than the second threshold.

Assignments (1)

Priority Claims (1)

Continuity (1)

References Cited (11)