Power supply circuit, control method and system

文档序号：452039 发布日期：2021-12-28 浏览：6次中文

阅读说明：本技术 一种供电电路、控制方法及系统 (Power supply circuit, control method and system ) 是由陈剑华周孟特范茂斌夏晓菲王利强于 2020-06-09 设计创作，主要内容包括：本申请公开了一种供电电路、控制方法及系统,用以降低LDO的功耗。供电电路包括控制电路、开关电源和多个LDO；该供电电路的控制电路在获取各LDO输出端的输出电压后,可根据各LDO的输出电压,调节与LDO的输入端一一对应连接的开关电源的输出端的电压,以使各LDO的输出电压为额定输出电压。本申请可根据各LDO的输出电压,调节与各LDO的输入端一一对应连接的开关电源的输出端的电压,以使各LDO的输出电压为额定输出电压,进而使得每个LDO的输入端和输出端的电压差值调节到接近dropout,提高LDO功耗的利用率。(The application discloses a power supply circuit, a control method and a system, which are used for reducing the power consumption of an LDO. The power supply circuit comprises a control circuit, a switching power supply and a plurality of LDOs; after the control circuit of the power supply circuit obtains the output voltage of each LDO output end, the voltage of the output end of the switching power supply connected with the input end of each LDO in a one-to-one correspondence mode can be adjusted according to the output voltage of each LDO, and therefore the output voltage of each LDO is the rated output voltage. This application can be according to the output voltage of each LDO, adjust the voltage of the switching power supply's that is connected with the input one-to-one of each LDO output to make the output voltage of each LDO be rated output voltage, and then make the voltage difference value of the input of every LDO and output adjust to being close dropout, improve the utilization ratio of LDO consumption.)

1. A power supply circuit, comprising: the low dropout linear regulator comprises a control circuit, a switching power supply and a plurality of LDOs;

the switching power supply comprises an input end and a plurality of output ends, the input end of the switching power supply is used for receiving battery voltage, the plurality of output ends of the switching power supply are respectively and correspondingly connected with the input ends of the plurality of LDOs, and the control end of the switching power supply is connected with the control circuit;

the output ends of the LDOs are respectively connected with a plurality of loads in a one-to-one correspondence manner;

the control circuit is respectively connected with the output ends of the LDOs, and is used for:

acquiring output voltage of an output end of each LDO;

and regulating the voltage of the output end of the switching power supply which is connected with the input end of each LDO in a one-to-one correspondence manner according to the output voltage of each LDO, so that the output voltage of each LDO is the rated output voltage.

2. The power supply circuit according to claim 1, wherein the switching power supply comprises: the voltage conversion unit and the plurality of switch units are connected with the LDOs in a one-to-one correspondence manner;

the input end of the voltage conversion unit is used for receiving the battery voltage, the output end of the voltage conversion unit is respectively connected with the input end of each switch unit, and the control end of the voltage conversion unit is connected with the control circuit;

for each switch unit, the control end of the switch unit is connected with the control circuit, and the output end of the switch unit is connected with the corresponding LDO;

the voltage conversion unit is used for:

outputting a switching voltage to the plurality of switching units under the control of the control circuit;

the control circuit is configured to:

regulating the first pulse signal according to the output voltage of the first LDO; the first LDO is any one of the plurality of LDOs; the first pulse signal is used for adjusting the output voltage of the output end of the switch unit connected with the first LDO.

3. The power supply circuit according to claim 2, wherein the voltage conversion unit includes: the inductor, the first control switch and the second control switch;

the first end of the first control switch receives the battery voltage, the second end of the first control switch is connected with the control circuit, and the third end of the first control switch is connected with one end of the inductor;

the first end of the second control switch is connected with one end of the inductor, the second end of the second control switch is connected with the control circuit, and the third end of the second control switch is grounded;

the other end of the inductor is connected with the plurality of switch units respectively, and the other end of the inductor is the output end of the voltage conversion unit;

the control circuit is specifically configured to:

and adjusting a second pulse signal of the first control switch and a third pulse signal of the second control switch to enable the voltage conversion unit to output the conversion voltage.

4. The power supply circuit according to claim 2 or 3, wherein the switching power supply further comprises: a third control switch;

a first end of the third control switch is connected with the output end of the voltage conversion unit, a second end of the third control switch is connected with the control circuit, and a third end of the third control switch is grounded;

the control circuit is further configured to:

determining that the output voltage of the output end of the switching power supply is not within the voltage requirement range of the first LDO under the action of the first pulse signal, and adjusting a fourth pulse signal; the fourth pulse signal is used for controlling the third control switch to adjust the current output by the voltage conversion unit to the plurality of switch units.

5. The power supply circuit according to claim 4, wherein the switching power supply further comprises capacitors connected in one-to-one correspondence with the output terminals of the plurality of switching units; the other ends of the capacitors are grounded;

the capacitor is used for filtering.

6. A power supply circuit, comprising: the low dropout linear regulator comprises a control circuit, a switching power supply, a plurality of LDOs (low dropout regulators), a plurality of sampling resistors and a sampling circuit;

the output ends of the LDOs are respectively connected with one ends of the sampling resistors in a one-to-one correspondence manner; the other ends of the sampling resistors are connected with the loads in a one-to-one correspondence manner;

the sampling circuit comprises a plurality of sampling ends and a plurality of output ends; the plurality of sampling ends are respectively connected with two ends of the plurality of sampling resistors in a one-to-one correspondence manner; the output ends are connected with the control circuit;

the control circuit is configured to:

acquiring the output current of the first LDO; the output current of the first LDO is determined by the sampling circuit according to the resistance value and the voltage value of a sampling resistor correspondingly connected with the first LDO; the first LDO is any one of the plurality of LDOs;

determining the current dropout of the first LDO according to the corresponding relation between the output current of the first LDO and the voltage difference dropout;

determining a target output voltage of the first output end according to the current dropout of the first LDO and the rated output voltage of the first LDO; the first output end is the output end of the switching power supply connected with the first LDO;

and controlling the switching power supply to output the target output voltage from the first output end.

7. The power supply circuit according to claim 6, wherein the switching power supply comprises: the voltage conversion unit and the plurality of switch units are connected with the LDOs in a one-to-one correspondence manner;

for each switch unit, the control end of the switch unit is connected with the control circuit, and the output end of the switch unit is connected with the corresponding LDO;

the voltage conversion unit is used for:

outputting a switching voltage to the plurality of switching units under the control of the control circuit;

the control circuit is configured to:

regulating the first pulse signal according to the output voltage of the first LDO; the first pulse signal is used for adjusting the output voltage of the output end of the switch unit connected with the first LDO.

8. The power supply circuit according to claim 7, wherein the voltage conversion unit comprises: the inductor, the first control switch and the second control switch;

the other end of the inductor is connected with the plurality of switch units respectively, and the other end of the inductor is the output end of the voltage conversion unit;

the control circuit is specifically configured to:

and adjusting a second pulse signal of the first control switch and a third pulse signal of the second control switch to enable the voltage conversion unit to output the conversion voltage.

9. The power supply circuit according to claim 7 or 8, wherein the switching power supply further comprises: a third control switch;

the control circuit is further configured to:

10. The power supply circuit according to claim 9, wherein the switching power supply further comprises capacitors connected in one-to-one correspondence with the output terminals of the plurality of switching units; the other ends of the capacitors are grounded;

the capacitor is used for filtering.

11. A control method applied to a control circuit in the power supply circuit according to any one of claims 1 to 5, the method comprising:

acquiring output voltage of an output end of each LDO;

12. A control method applied to a control circuit in the power supply circuit according to any one of claims 6 to 10, the method comprising:

determining the current dropout of the first LDO according to the corresponding relation between the output current of the first LDO and the voltage difference dropout;

and controlling the switching power supply to output the target output voltage from the first output end.

13. A system comprising a plurality of loads, a battery, and a power supply circuit according to any one of claims 1-5;

one end of the power supply circuit is connected with the battery, and the other end of the power supply circuit is respectively connected with the plurality of loads;

the battery is used for providing voltage for the power supply circuit;

the power supply circuit is used for providing working voltage for the plurality of loads.

14. A system comprising a plurality of loads, a battery and a power supply circuit according to any one of claims 6 to 10;

one end of the power supply circuit is connected with the battery, and the other end of the power supply circuit is respectively connected with the plurality of loads;

the battery is used for providing voltage for the power supply circuit;

the power supply circuit is used for providing working voltage for the plurality of loads.

Technical Field

The present application relates to the field of terminal technologies, and in particular, to a power supply circuit, a control method, and a system.

Background

With the increasingly competitive electronic market, the power consumption of electronic devices becomes one of the important indicators for measuring the performance of electronic devices. At present, Power Management Units (PMUs) are often disposed in electronic devices, and the PMUs are respectively connected to a battery and a load in the electronic devices, and can regulate an output voltage of the battery, thereby supplying power to the load.

Specifically, the PMU typically includes a switching power supply and a low dropout regulator (LDO). The switching power supply is connected with the battery, can reduce the voltage of the received battery, and provides the reduced voltage of the battery as output voltage for the LDO. The input end of the LDO is connected with the switching power supply, and the output end of the LDO is connected with the load. The LDO can receive the output voltage of the switching power supply and regulate the output voltage of the switching power supply, so that the required working voltage is provided for the load.

Generally, there may be a plurality of loads with different operating voltages in an electronic device, so that a plurality of LDOs are disposed in the PMU, input ends of the LDOs are all connected to the switching power supply, and output ends of the LDOs can respectively output voltages with different magnitudes, so as to respectively supply power to the plurality of loads.

Specifically, a voltage difference dropout exists in the LDO, and the voltage difference is the minimum input voltage and the output voltage of the LDO. However, in the working process of the electronic device, the larger the input voltage of the LDO is, the larger the voltage difference between the input voltage and the output voltage of the LDO is, and the larger the difference between the voltage difference and dropout of the LDO is, so that the power consumption of the LDO is increased, and the power consumption of the PMU is increased.

Disclosure of Invention

The embodiment of the application provides a power supply circuit, a control method and a system, which are used for reducing the power consumption of an LDO.

In a first aspect, an embodiment of the present application provides a power supply circuit, which mainly includes: the control circuit, the switching power supply and the plurality of LDOs; the switching power supply comprises an input end and a plurality of output ends; the input end of the switching power supply is used for receiving the voltage of the battery, a plurality of output ends of the switching power supply are respectively and correspondingly connected with the input ends of the LDOs, and the control end of the switching power supply is connected with the control circuit; the output ends of the LDOs are respectively connected with the loads in a one-to-one correspondence manner; the control circuit is respectively connected with the output ends of the LDOs. The control circuit can adjust the voltage of the output end of the switching power supply which is connected with the input end of each LDO in a one-to-one correspondence mode according to the output voltage of each LDO after the output voltage of the output end of each LDO is obtained, so that the output voltage of each LDO is the rated output voltage.

In this application embodiment, owing to used the switching power supply of single input many outputs, and can be according to the output voltage of the LDO of gathering in real time, the voltage of the output that real-time regulation switching power supply and LDO correspond for the output voltage of LDO is rated output voltage, and then makes the voltage difference value of the input of every LDO and output adjust to being close dropout, reduces the loss of the consumption of LDO.

In one possible implementation, a switching power supply includes: the voltage conversion unit and the plurality of switch units are connected with the plurality of LDOs in a one-to-one correspondence manner; the input end of the voltage conversion unit is used for receiving the voltage of the battery, the output end of the voltage conversion unit is respectively connected with the input end of each switch unit, and the control end of the voltage conversion unit is connected with the control circuit; for each switch unit, the control end of the switch unit is connected with the control circuit, and the output end of the switch unit is connected with the corresponding LDO. The voltage conversion unit can output conversion voltage to the plurality of switch units under the control of the control circuit. The control circuit can regulate the first pulse signal according to the output voltage of the first LDO; the first LDO is any one of a plurality of LDOs; the first pulse signal is used for regulating an output voltage of an output end of a switch unit connected with the first LDO.

In this application embodiment, switching power supply obtains the converted voltage through voltage conversion unit conversion battery voltage to with the converted voltage output for the switch unit, and after control circuit acquireed the output voltage of LDO behind switching power supply's the switch unit input pulse signal, so that switching power supply adjusts its voltage with the output that LDO corresponds according to pulse signal, and then makes the voltage difference value of the input of every LDO and output adjust to being close dropout.

In one possible implementation, the voltage converting unit includes: the inductor, the first control switch and the second control switch; the first end of the first control switch receives the voltage of the battery, the second end of the first control switch is connected with the control circuit, and the third end of the first control switch is connected with one end of the inductor; the first end of the second control switch is connected with one end of the inductor, the second end of the second control switch is connected with the control circuit, and the third end of the second control switch is grounded; the other end of the inductor is connected with the plurality of switch units respectively, and the other end of the inductor is an output end of the voltage conversion unit. The control circuit can enable the voltage conversion unit to output the conversion voltage by adjusting the second pulse signal of the first control switch and the third pulse signal of the second control switch.

In the embodiment of the application, the control circuit adjusts the pulse signals of the first control switch and the second control switch to output the conversion voltage so as to meet the voltage requirement of each LDO.

In one possible implementation, the switching power supply further includes: a third control switch; the first end of the third control switch is connected with the output end of the voltage conversion unit, the second end of the third control switch is connected with the control circuit, and the third end of the third control switch is grounded. The control circuit determines that the output voltage of the output end of the switching power supply is not within the voltage requirement range of the first LDO under the action of the first pulse signal, and then adjusts the fourth pulse signal; the fourth pulse signal is used for controlling the third control switch to adjust the current output by the voltage conversion unit to the plurality of switch units.

In the embodiment of the application, the pulse signal of the third control switch is adjusted by the control circuit, so that the voltage adjusted by the switch unit meets the voltage requirement of each LDO.

In one possible implementation manner, the switching power supply further includes capacitors connected in one-to-one correspondence with the output terminals of the plurality of switching units; the other ends of the capacitors are grounded; the capacitor is used for filtering.

In the embodiment of the application, the working performance of the switching power supply is more stable through the capacitor filtering clutter.

In a second aspect, an embodiment of the present application provides a power supply circuit, which mainly includes: the low dropout linear regulator comprises a control circuit, a switching power supply, a plurality of LDOs (low dropout regulators), a plurality of sampling resistors and a sampling circuit; the switching power supply comprises an input end and a plurality of output ends; the input end of the switching power supply is used for receiving the voltage of the battery, a plurality of output ends of the switching power supply are respectively and correspondingly connected with the input ends of the LDOs, and the control end of the switching power supply is connected with the control circuit; the output ends of the LDOs are respectively connected with one ends of the sampling resistors in a one-to-one correspondence manner; the other ends of the sampling resistors are connected with the loads in a one-to-one correspondence manner; the sampling circuit comprises a plurality of sampling ends and a plurality of output ends; the plurality of sampling ends are respectively connected with two ends of the plurality of sampling resistors in a one-to-one correspondence manner; the output ends are connected with the control circuit; the control circuit can obtain the output current of the first LDO; determining the current dropout of the first LDO according to the corresponding relation between the output current of the first LDO and the voltage difference dropout; determining a target output voltage of a first output end according to the current dropout of the first LDO and the rated output voltage of the first LDO; controlling the switching power supply to output a target output voltage from a first output end; the output current of the first LDO is determined by the sampling circuit according to the resistance value and the voltage value of the sampling resistor correspondingly connected with the first LDO; the first LDO is any one of a plurality of LDOs; the first output end is an output end of the switching power supply connected with the first LDO.

In this application embodiment, owing to applied single input multi-output's switching power supply, and can be according to the output current of LDO and the corresponding relation between dropout, confirm the target output voltage of the input that switching power supply should give LDO, adjust the voltage of the output that switching power supply and LDO correspond for switching power supply's output target output voltage, and then make the voltage difference value of the input of every LDO and output adjust to and be close dropout, reduce the loss of the consumption of LDO.

In one possible implementation, a switching power supply includes: the voltage conversion unit and the plurality of switch units are connected with the plurality of LDOs in a one-to-one correspondence manner; the input end of the voltage conversion unit is used for receiving the voltage of the battery, the output end of the voltage conversion unit is respectively connected with the input end of each switch unit, and the control end of the voltage conversion unit is connected with the control circuit; for each switch unit, the control end of the switch unit is connected with the control circuit, and the output end of the switch unit is connected with the corresponding LDO. The voltage conversion unit can output conversion voltage to the plurality of switch units under the control of the control circuit. The control circuit can regulate the first pulse signal according to the output voltage of the first LDO; the first pulse signal is used for adjusting the output voltage of the output end of the switch unit connected with the first LDO.

In this application embodiment, switching power supply obtains the converted voltage through voltage conversion unit conversion battery voltage to with the converted voltage output for the switch unit, and after control circuit acquireed the output current of LDO after the switch unit input pulse signal of switching power supply, so that switching power supply adjusts its voltage with the output that LDO corresponds according to pulse signal, and then makes the voltage difference value of the input of every LDO and output adjust to being close dropout.

In the embodiment of the application, the working performance of the switching power supply is more stable through the capacitor filtering clutter.

In a third aspect, an embodiment of the present application provides a control method, which is applied to a control circuit in the power supply circuit of the first aspect, and the method includes: acquiring output voltage of an output end of each LDO; and regulating the voltage of the output end of the switching power supply which is connected with the input end of each LDO in a one-to-one correspondence manner according to the output voltage of each LDO, so that the output voltage of each LDO is the rated output voltage.

In this application embodiment, owing to used the switching power supply of single input multi-output, and can be according to the output voltage of the LDO of gathering in real time, the voltage of the output that real-time regulation switching power supply and LDO correspond for the output voltage of LDO is rated output voltage, and then makes the voltage difference value of the input of every LDO and output adjust to being close dropout, reduces the consumption of LDO.

In a fourth aspect, an embodiment of the present application provides a control method, which is applied to a control circuit in the power supply circuit of the second aspect, and the method includes: acquiring the output current of the first LDO; the output current of the first LDO is determined by the sampling circuit according to the resistance value and the voltage value of the sampling resistor correspondingly connected with the first LDO; the first LDO is any one of a plurality of LDOs; determining the current dropout of the first LDO according to the corresponding relation between the output current of the first LDO and the voltage difference dropout; determining a target output voltage of a first output end according to the current dropout of the first LDO and the rated output voltage of the first LDO; the first output end is the output end of the switching power supply connected with the first LDO; and controlling the switching power supply to output the target output voltage from the first output end.

In this application embodiment, owing to used single input multi-output's switching power supply, and can be according to the output current of LDO and the corresponding relation between dropout, confirm the target output voltage of the input that switching power supply should give LDO, adjust the voltage of the output that switching power supply and LDO correspond for switching power supply's output target output voltage, and then make the voltage difference value of the input of every LDO and output adjust to and be close dropout, reduce the consumption of LDO.

In a fifth aspect, embodiments of the present application provide a system, which may be an electronic device. Technical effects of the corresponding solutions in the fifth aspect can be referred to technical effects that can be obtained by the corresponding solutions in the first aspect, and repeated parts are not detailed. For example, the system provided by the embodiment of the present application may include a plurality of loads, a battery, and the power supply circuit according to the first aspect; one end of the power supply circuit is connected with the battery, and the other end of the power supply circuit is respectively connected with the plurality of loads; the battery is used for providing voltage for the power supply circuit; the power supply circuit is used for providing working voltage for a plurality of loads.

In a sixth aspect, embodiments of the present application provide a system, which may be an electronic device. Technical effects of the corresponding aspects in the sixth aspect can be obtained by referring to technical effects that can be obtained by the corresponding aspects in the second aspect, and repeated points are not detailed. For example, the system provided by the embodiment of the present application may include a plurality of loads, a battery, and a power supply circuit as in the second aspect; one end of the power supply circuit is connected with the battery, and the other end of the power supply circuit is respectively connected with the plurality of loads; the battery is used for providing voltage for the power supply circuit; the power supply circuit is used for providing working voltage for a plurality of loads.

These and other aspects of the present application will be more readily apparent from the following description of the embodiments.

Drawings

FIG. 1 shows a schematic diagram of a prior art PMU circuit;

FIG. 2 shows a schematic diagram of a prior art PMU circuit;

FIG. 3A shows a schematic diagram of a power supply circuit provided by an embodiment of the present application;

FIG. 3B is a schematic diagram of a power supply circuit provided by an embodiment of the present application;

fig. 4 is a schematic diagram of a switching power supply provided by an embodiment of the present application;

fig. 5 shows a schematic diagram of a voltage conversion unit provided by an embodiment of the present application;

fig. 6 is a schematic diagram of a switching power supply provided by an embodiment of the present application;

fig. 7 is a schematic diagram of a switching power supply provided by an embodiment of the present application;

fig. 8 is a schematic diagram of a switching power supply provided by an embodiment of the present application;

FIG. 9 is a schematic diagram of a power supply circuit provided by an embodiment of the present application;

FIG. 10 is a schematic diagram illustrating waveforms provided by embodiments of the present application;

FIG. 11 shows a schematic diagram of a power supply circuit provided by an embodiment of the present application;

FIG. 12 is a flow chart illustrating a control method provided by an embodiment of the present application;

fig. 13 shows a flowchart of a control method provided in an embodiment of the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be described in detail below with reference to the drawings in the embodiments of the present application.

As described in the background, PMUs typically include a BUCK switch power supply through which battery voltage is received and LDOs through which a load is powered, as shown in fig. 1. However, the operating voltages of different loads are different, and one LDO can only output a voltage within the rated output voltage range, so that different LDOs are required to supply power to different loads.

As shown in fig. 2, BUCK switching power supply 1 is connected to LDO1 and LDO2, respectively, LDO1 is connected to load 1, and LDO2 is connected to load 2. The input voltage provided by the switching power supply 1 is 0.9V, the rated output voltage of the LDO1 should be 0.6V, but the actual output voltage of the LDO1 is 0.62V, and assuming that the minimum drop of the LDO1 is 0.12V, the voltage difference between the input end and the output end of the LDO1 is 0.28V when the switching power supply 1 supplies power, and the voltage difference is 0.16V different from the minimum drop of the LDO 1; the input voltage provided by the switching power supply 1 is 0.9V, the rated output voltage of the LDO2 should be 0.7V, but the actual output voltage of the LDO2 is 0.69V, and assuming that the minimum drop of the LDO2 is 0.15V, the difference between the input voltage and the output voltage of the LDO2 is 0.21V and 0.06V different from the minimum drop of the LDO2 when the switching power supply 1 supplies power. The power consumption of the LDO is affected by the voltage difference value and dropout, the larger the difference between the voltage difference value and dropout is, the larger the power consumption is, the smaller the difference between the voltage difference value and dropout is, and the smaller the power consumption is. In fig. 2, the difference between the voltage difference and dropout of each LDO is different, so that the power consumption of LDO1 is relatively large, and the power consumption of LDO2 is relatively small.

Therefore, the same BUCK switch power supply is adopted to supply power to different LDOs, and the power consumption utilization rate of different LDOs cannot be the highest. In addition, dropout in the LDO is positively correlated with the output current of the LDO, that is, the larger the output current is, the larger dropout of the LDO is; the output current is smaller, the drop of the LDO is smaller, the output voltage of the BUCK switch power supply is relatively fixed and cannot be regulated, even if the output current of the LDO is I₁Determining a BUCK switch power supply B which enables the power consumption utilization rate of the LDO to be highest₁Once the LDO output current changes to I₂While the dropout of LDO is also changed, the BUCK switches the power supply B₁The power consumption utilization of the LDO cannot be maximized.

Based on this, the embodiment of the application provides a power supply circuit to reduce the loss of the power consumption of the LDO.

The operation of the power supply circuit is described in detail below, and in order to make the objects, technical solutions and advantages of the present application more clear, the present application will be further described in detail with reference to the accompanying drawings. It should be noted that, in the description of the embodiments of the present application, "at least one" means one or more, where a plurality means two or more. In view of this, the "plurality" may also be understood as "at least two" in the embodiments of the present invention. "and/or" describes the association relationship of the associated objects, meaning that there may be three relationships, e.g., a and/or B, which may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" generally indicates that the preceding and following related objects are in an "or" relationship, unless otherwise specified. In addition, it is to be understood that the terms first, second, etc. in the description of the present application are used for distinguishing between the descriptions and not necessarily for describing a sequential or chronological order.

It is to be noted that "connected" in the embodiments of the present application refers to an electrical connection, and the connection of two electrical components may be a direct or indirect connection between the two electrical components. For example, a and B may be connected directly, or a and B may be connected indirectly through one or more other electrical elements, for example, a and B may be connected, or a and C may be connected directly, or C and B may be connected directly, and a and B are connected through C.

The application provides a supply circuit, includes: the control circuit, the switching power supply and the plurality of LDOs; the input end of the switch power supply receives the battery voltage, and the switch power supply comprises an input end and a plurality of output ends; a plurality of output ends of the switching power supply are respectively and correspondingly connected with the input ends of the LDOs, and a control end of the switching power supply is connected with the control circuit; the output ends of the LDOs are respectively connected with the loads in a one-to-one correspondence manner; the control circuit is respectively connected with the output ends of the LDOs. In practical application, how many LDOs are specifically selected, what type of LDOs are selected, and the selection can be performed according to product requirements, and is not specifically limited herein. In addition, the switching power supply, the control circuit and the plurality of LDOs may be integrated into one device, or may be respectively used as three devices, or any two of the two parts may be integrated into one device to provide voltage for the load, which is not specifically limited herein.

The control circuit is used for: and acquiring the output voltage of the output end of each LDO, and regulating the voltage of the output end of the switching power supply connected with the input end of each LDO in a one-to-one correspondence manner according to the output voltage of each LDO so as to enable the output voltage of each LDO to be the rated output voltage. In the related art, the output voltage of a switching power supply is fixed, and it is possible to supply power to different loads by connecting a plurality of different LDOs, such as: the output voltage of the switching power supply is 1V, the back of the switching power supply may be connected with an LDO1 with rated output voltage of 0.6V, and the LDO2 with rated output voltage of 0.8V, so that the difference between the input voltage received by the LDO through the switching power supply and the output voltage of the LDO is large, and the power consumption loss of the LDO may be large. In the embodiment of the application, the voltage of the output end of the switching power supply corresponding to the LDO can be adjusted according to the output voltage of the LDO, so that the voltage difference value of the input end and the output end of each LDO is adjusted to be close to dropout, and the loss of power consumption is reduced.

For an exemplary illustration of the power supply circuit provided by the present application, reference may be made to the schematic diagram shown in fig. 3A, which includes a battery, a switching power supply, a control circuit, LDO1, LDO2, LDO3, load 1, load 2, and load 3, where LDO1 is connected to load 1; LDO2 is connected to load 2; LDO3 is connected to load 3, where the load may be an electronic component such as: resistors, light emitting diodes, etc.; it may also be a chip such as: graphics Processing Unit (GPU), memory, etc.; the load may also be a circuit constructed by a plurality of electronic components and chips, and the load is not specifically limited herein, and any load that can be supplied with power through the LDO is suitable for the present application. In addition, since the operation of the control circuit to obtain the output voltage of the LDO is consistent, the LDO1 is exemplified herein. The control circuit collects the output voltage of the LDO1 in real time, and adjusts the output voltage of the output end of the switching power supply connected with the LDO1 in real time according to the output voltage of the LDO1, so that the output end of the LDO1 outputs the rated output voltage of the LDO1, when the LDO1 outputs the rated output voltage, the difference value between the output voltage of the switching power supply received by the LDO1 and the output voltage of the LDO1 is just equal to the dropout of the LDO1, and therefore the power consumption utilization rate of the LDO1 is the highest.

In order to reduce the power consumption of the LDO, an embodiment of the present application further provides another power supply circuit, where the power supply circuit includes: the device comprises a control circuit, a switching power supply, a plurality of LDOs (low dropout regulators), a plurality of sampling resistors and a sampling circuit; the switching power supply comprises an input end and a plurality of output ends; the input end of the switching power supply is used for receiving the voltage of the battery, a plurality of output ends of the switching power supply are respectively and correspondingly connected with the input ends of the LDOs, and the control end of the switching power supply is connected with the control circuit; the output ends of the LDOs are respectively connected with one ends of the sampling resistors in a one-to-one correspondence manner; the other ends of the sampling resistors are connected with the loads in a one-to-one correspondence manner; the sampling circuit comprises a plurality of sampling ends and a plurality of output ends; the plurality of sampling ends are respectively connected with two ends of the plurality of sampling resistors in a one-to-one correspondence manner; the output ends are connected with the control circuit; in practical application, how many LDOs are specifically selected, what type of LDOs are selected, and the selection can be performed according to product requirements, and is not specifically limited herein. In addition, the switching power supply, the control circuit, the sampling circuit, and the plurality of LDOs may be integrated into one device, or may be respectively used as four devices, or any two of the two devices may be integrated into one device to provide voltage for the load, which is not specifically limited herein.

Wherein the sampling circuit is configured to: acquiring a voltage value of a first sampling resistor, wherein the first sampling resistor is a sampling resistor correspondingly connected with the first LDO, and the first sampling resistor is arranged between the output end of the first LDO and a first load; calculating to obtain a current value of the output current of the first LDO according to the voltage value of the first sampling resistor and the resistance value of the first sampling resistor; sending an output current of the first LDO to a control circuit; the first LDO is any one of a plurality of LDOs. The sampling circuit can be realized by an operational amplifier, and can also be used as a sampling circuit to obtain the output current of the LDO through other devices. In addition, when the resistance value of the sampling resistor is selected, the resistor with the small resistance value is selected as far as possible, so that the sampling resistor is prevented from consuming a large amount of voltage of a load and influencing the normal work of the load, and for example, the resistor of 5u omega can be selected as the sampling resistor. In addition, the sampling circuit records the resistance value of the sampling resistor, and obviously, the current of the sampling resistor, namely the output current of the LDO can be obtained by obtaining the voltage value of the sampling resistor.

The control circuit is used for: acquiring the output current of the first LDO; the output current of the first LDO is determined by the sampling circuit according to the resistance value and the voltage value of the sampling resistor correspondingly connected with the first LDO; determining the current dropout of the first LDO according to the corresponding relation between the output current of the first LDO and the voltage difference dropout; determining a target output voltage of a first output end according to the current dropout of the first LDO and the rated output voltage of the first LDO; the first output end is the output end of the switching power supply connected with the first LDO; and controlling the switching power supply to output the target output voltage from the first output end.

The corresponding relation can be stored in the form of a chart, such as: in the form of the scatter diagram and the data table, the corresponding relationship is stored in the form of the data table, but the storage form of the corresponding relationship is not specifically limited in practical application, which schematically illustrates that, as shown in table 1, in practical application, the values of the output current of the first LDO and the dropout are not limited in the corresponding relationship, the corresponding relationship between the output current of the LDO and the value of the dropout during the actual working process of the LDO may be stored in the control circuit, or the corresponding relationship between the output current of the LDO and the value of the dropout acquired in other manners may be stored in the control circuit. When the output current of the LDO in the table 1 is 1mA, the minimum dropout of the LDO is 50 mV; when the output current of the LDO is 10mA, the minimum dropout of the LDO is 100 mV; when the output current of the LDO is 100mA, the minimum dropout of the LDO is 150 mV; when the output current of the LDO is 1000mA, the minimum dropout of the LDO is 200 mV.

TABLE 1

Output current of LDO	LDO minimum dropout
		1mA	50mV
10mA	100mV
		100mA	150mV
1000mA	200mV

If the output current of the LDO is 1mA, the rated output voltage of the LDO is 0.6V, and it can be known from table 1 that dropout corresponding to 1mA is 50mV, then it can be known through table lookup of the control circuit that the target output voltage is 0.6V +50mV, that is, 0.65V, so that the output end of the switching power supply is adjusted to output a voltage of 0.65V to meet the requirement.

For an exemplary illustration of the power supply circuit provided by the present application, reference may be made to a schematic diagram shown in fig. 3B, which includes a battery, a switching power supply, a control circuit, a sampling resistor 1, a sampling resistor 2, a sampling resistor 3, an LDO1, an LDO2, an LDO3, a load 1, a load 2, and a load 3, where the LDO1 is connected to the sampling resistor 1, and the sampling resistor 1 is connected to the load 1; the LDO2 is connected with the sampling resistor 2, and the sampling resistor 2 is connected with the load 2; LDO3 is connected to sampling resistor 3, and sampling resistor 3 is connected to load 3. In addition, since the operation of the control circuit to obtain the output current of the LDO is consistent, the LDO1 is exemplified herein. The sampling circuit determines a current value (namely the output current of the LDO 1) flowing through the sampling resistor 1 according to the voltage value at the two ends of the sampling resistor 1 and the resistance value of the sampling resistor 1, and queries a current dropout corresponding to the current output current of the LDO 1; the target output voltage to be output by the output terminal connected with LDO1 is determined according to the current dropout of LDO1 and the rated output voltage of LDO 1.

It should be noted that, the switching power supply of the power supply circuit in the present application may be implemented by a single-Inductor multiple-output (SIMO) switching power supply, and may also be implemented by other switching power supplies capable of outputting multiple voltages, which is not specifically limited herein, and all circuits consistent with the implementation functions of the switching power supply circuit in the present application are applicable to the present application. As shown in fig. 4, the switching power supply includes a voltage conversion unit and a switching unit connected to the plurality of LDOs in a one-to-one correspondence; the input end of the voltage conversion unit is used for receiving the voltage of the battery, the output end of the voltage conversion unit is respectively connected with the input end of each switch unit, and the control end of the voltage conversion unit is connected with the control circuit. For each switch unit, the control end of the switch unit is connected with the control circuit, and the output end of the switch unit is connected with the corresponding LDO. Fig. 4 schematically shows that the switching power supply comprises a voltage conversion unit, a first switching unit, a second switching unit and a third switching unit, wherein the first switching unit is connected with the LDO 1; the second switching unit is connected with the LDO 2; the third switching unit is connected to LDO 3.

Wherein the voltage conversion unit is used for: the switching voltage is output to the plurality of switching units under the control of the control circuit. Because the voltage of the battery is higher, the load can be burnt out by directly supplying power to the load, and therefore, the voltage of the battery can be reduced through the voltage conversion unit so as to be more adaptive to the requirement of the load.

Wherein the control circuit is configured to: regulating the first pulse signal according to the output voltage of the first LDO; the first LDO is any one of a plurality of LDOs; the first pulse signal is used for regulating an output voltage of an output end of a switch unit connected with the first LDO.

The control circuit adjusts the switching power supply voltage by adjusting the pulse duty ratio and/or the pulse frequency in the pulse signal, the pulse signal mentioned in the application can be displayed by a rectangular square wave, the pulse duty ratio is adjusted, namely the width of a high-level signal in one signal period in the rectangular square wave and the frequency of the pulse are adjusted, namely the occurrence frequency of the signal period in each second is adjusted, but the duty ratio of the high-level pulse in the signal period is unchanged. The high level pulse is also a pulse when the circuit is turned on, and the low level pulse is also a pulse when the circuit is not turned on.

Assuming that the signal period of the pulse signal is 1 minute, wherein the duty ratio of the high-level pulse is 50%, the duty ratio of the low-level pulse is 50%, and the pulse frequency is 5 times, the voltage can be adjusted by adjusting the duty ratio of the high-level pulse, such as: the voltage is increased by increasing the duty ratio of the high level in the signal period, and the voltage is also decreased by decreasing the duty ratio of the high level in the signal period; or adjusting the number of times of the pulse frequency to adjust the voltage, such as: the voltage is increased by increasing the number of times of the pulse frequency, and the voltage can also be decreased by decreasing the number of times of the pulse frequency; or the voltage is adjusted by changing the duty ratio and the pulse frequency of the high-level pulse.

In the embodiment of the application, the switching power supply converts the battery voltage through the voltage conversion unit to obtain the conversion voltage, and outputs the conversion voltage to the switching unit. After the switching unit of the switching power supply receives the pulse signal of the control circuit, the output voltage of the switching unit is adjusted through the pulse signal, so that the voltage of the output end of the switching power supply can be adjusted according to the sampling signal of the LDO, and further the voltage difference value of the input end and the output end of each LDO is adjusted to be close to the dropout voltage, and further the reduction of power consumption is facilitated.

Illustratively, the voltage converting unit, as shown in fig. 5, may include: an inductor L1, a first control switch T1 and a second control switch T2; a first end of the first control switch T1 receives the battery voltage, a second end of the first control switch T1 is connected with the control circuit, and a third end of the first control switch T1 is connected with one end of the inductor L1; a first end of the second control switch T2 is connected with one end of the inductor L1, a second end of the second control switch T2 is connected with the control circuit, and a third end of the second control switch T2 is grounded; the other end of the inductor L1 is connected to the plurality of switch units, respectively, and the other end of the inductor L1 is an output end of the voltage conversion unit.

The control circuit is specifically configured to: the second pulse signal of the first control switch T1 and the third pulse signal of the second control switch T2 are adjusted so that the voltage converting unit outputs the converted voltage.

It should be noted that the second pulse signal and the third pulse signal exist relatively, and if the second pulse signal is at a high level, the third pulse signal is at a low level, that is, when the first control switch T1 is turned on, the second control switch T2 is turned off; when the first control switch T1 is turned off, the second control switch T2 is turned on. When the first control switch T1 is turned on and the second control switch T2 is turned off, the battery supplies power to the inductor L1; when the first control switch T1 is turned off and the second control switch T2 is turned on, the second control switch T2 and the inductor L1 form a closed loop, so that the inductor L1 can supply current to the loop. Therefore, the voltage exists at the output end of the voltage conversion unit, and different conversion voltages are output by adjusting the second pulse signal and the third pulse signal so as to adapt to the requirements of more LDOs.

Illustratively, the switching power supply further includes a third control switch T3 as shown in fig. 6, wherein a first terminal of the third control switch T3 is connected to the output terminal of the voltage converting unit, a second terminal of the third control switch T3 is connected to the control circuit, and a third terminal of the third control switch T3 is grounded.

Wherein the control circuit is further configured to: and if the output voltage of the output end of the third switching power supply is determined not to be within the voltage requirement range of the first LDO under the action of the first pulse signal, adjusting a fourth pulse signal, wherein the fourth pulse signal is used for controlling a third control switch T3 to adjust the current output by the voltage conversion unit to the plurality of switching units.

It should be noted that, the control circuit needs to regulate and control the output voltages of the multiple switching units through the pulse signals, the working states of the LDOs connected to different switching units are different, and for the power supply circuit in fig. 3A, the voltage demand range of the first LDO is a voltage that makes the output voltage of the LDO a rated output voltage, and some switching power supplies can make the voltage of the output end of the switching unit the rated output voltage of the LDO by regulating the first pulse signal through the control circuit, but some switching units cannot meet the voltage demand of the LDO no matter how the voltage of the output end is regulated, so that the excess current at the output end of the power-down inductor needs to be discharged through the third control switch T3, so that the voltage regulated by the switching units meets the voltage demand of the LDO; for the power supply circuit in fig. 3B, the voltage demand range of the first LDO is the voltage that makes the input voltage of the LDO be the target output voltage, and some switching power supplies can make the output end of the switching unit output the target output voltage by adjusting the first pulse signal through the control circuit, but some switching units cannot meet the voltage demand of the LDO no matter how to adjust the voltage of the output end, so that the third control switch T3 is needed to discharge the redundant current at the output end of the power down inductor, so that the voltage adjusted by the switching unit meets the voltage demand of the LDO.

In the embodiment of the present application, the pulse signal of the third control switch is adjusted by the control circuit, so that the voltage adjusted by the switch unit meets the voltage requirement of the LDO.

Illustratively, the switching power supply further includes capacitors connected to the output terminals of the plurality of switching units in a one-to-one correspondence, as shown in fig. 7, where the capacitors are illustrated by C1, C2, and C3, and the other ends of the plurality of capacitors are grounded; in fig. 7, C1 has one end connected to the first switch unit and one end connected to ground. The capacitor is used for filtering. The working performance of the switching power supply is more stable through the capacitor, and noise waves are filtered.

It should be noted that the first control switch, the second control switch, the third control switch, and the switch unit may be a metal-oxide-semiconductor field-effect transistor (MOSFET) as shown in fig. 8, or may be other three-terminal input switches having an input terminal, an output terminal, and a control terminal, and are not limited in this respect. In fig. 8, MOS1 is a first control switch, MOS2 is a second control switch, MOS3 is a third control switch, MOS4 is switch unit 1, MOS5 is switch unit 2, and MOS6 is switch unit 3. The control circuit inputs a third pulse signal to the MOS1 by inputting the second pulse signal to the MOS1, so that the voltage conversion unit converts the battery voltage, and drains an unnecessary current through the MOS 3. The control circuit adjusts the respective corresponding pulse signals of the MOS4-MOS6, so that the output ends of the MOS4-MOS6 meet the voltage requirements of the respective LDOs.

The control circuit can adjust the output voltage of the output end of the switching power supply according to the output voltage of each LDO, so that the output voltage of each LDO is the rated output voltage. The control circuit can adjust and control the voltage at the output end of the switching power supply in real time by obtaining the output voltage at the output end of each LDO to meet the requirement of the LDO, as shown in fig. 9, where fig. 9 is illustrated on the basis of fig. 8, and a power supply circuit can also be illustrated on the basis of any switching power supply in fig. 4-7. It should be noted that each LDO corresponds to its rated output voltage, and when the voltage output by the output terminal of the LDO happens to be the rated output voltage, the voltage difference between the input terminal and the output terminal of the LDO is dropout. Such as: rated output voltage of LDO1 is 0.6V, and the voltage that control circuit obtained LDO1 output through the sampling is 0.62V, so, control circuit can adjust the pulse signal who inputs to MOS4 for the output that is connected with LDO1 outputs 0.6V, and then has just also improved LDO 1's power consumption utilization. Fig. 10 schematically illustrates a waveform diagram of a pulse signal for regulating MOS4 and a waveform variation diagram of an output voltage of LDO1, when the output voltage of LDO1 is lower than a rated output voltage, a duty ratio of a high-level pulse signal in one pulse signal period is increased, so that a voltage at an output terminal of LDO1 is increased; the duty ratio of the pulse signal with the low level in one pulse signal period when the output voltage of the LDO1 is just the rated output voltage; when the output voltage of LDO1 is higher than the rated output voltage, the duty cycle of the high-level pulse signal in one pulse signal period is reduced, so that the voltage at the output terminal of LDO1 is reduced. Because the output voltage of LDO is gathered in real time, and control circuit adjusts the voltage of LDO input end input according to the LDO output voltage who gathers in real time, and then makes the output voltage of LDO be rated output voltage, has reduced the loss of the consumption of LDO through this mode.

The control circuit can adjust the output voltage of the output end of the switching power supply according to the output current of each LDO so as to reduce the power consumption of the LDO. The control circuit can adjust and control the voltage at the output end of the switching power supply in real time by obtaining the output current at the output end of each LDO to meet the requirement of the LDO, as shown in fig. 11, where fig. 11 is illustrated on the basis of fig. 8, and a power supply circuit can also be illustrated on the basis of any switching power supply in fig. 4-7. Both ends of the sampling resistor R1, the sampling resistor R2 and the sampling resistor R3 are connected with the sampling circuit. If the sampling circuit obtains the voltage value of the sampling resistor R1, the output current of the LDO1 is determined through calculation, the output current of the LDO1 is fed back to the control circuit, the control circuit determines the current dropout by inquiring the corresponding relation between the output current of the LDO1 and the dropout, determines the target output voltage based on the current dropout and the rated output voltage of the LDO1, and adjusts the voltage of the output end of the switching power supply corresponding to the LDO1 based on the target output voltage. The voltage difference value of the input end and the output end of the LDO is dropout through the method, and therefore the power consumption utilization rate of the LDO is improved.

Based on the same technical concept, the embodiment of the application also provides a control method. The method may be applied to the control circuit in the power supply circuit shown in fig. 3A, which is not described again in this embodiment of the present application. Fig. 12 is a schematic flowchart illustrating a control method provided by an embodiment of the present application. The method mainly comprises the following steps:

step 1201, obtaining the output voltage of the output end of each LDO.

And step 1202, according to the output voltage of each LDO, adjusting the voltage of the output end of the switching power supply which is connected with the input end of each LDO in a one-to-one correspondence manner, so that the output voltage of each LDO is the rated output voltage.

The embodiment of the application also provides another control method. The method may be applied to the control circuit in the power supply circuit shown in fig. 3B, which is not described again in this embodiment of the present application. Fig. 13 is a schematic flowchart illustrating a control method provided by an embodiment of the present application. The method mainly comprises the following steps:

step 1301, acquiring output current of the first LDO; the output current of the first LDO is determined by the sampling circuit according to the resistance value and the voltage value of the sampling resistor correspondingly connected with the first LDO; the first LDO is any one of a plurality of LDOs.

In step 1302, a current dropout of the first LDO is determined according to a corresponding relationship between an output current of the first LDO and a voltage difference dropout.

Step 1303, determining a target output voltage of the first output end according to the current dropout of the first LDO and the rated output voltage of the first LDO; the first output end is an output end of the switching power supply connected with the first LDO.

Step 1304, controlling the switching power supply to output a target output voltage from the first output terminal.

The embodiment of the present application further provides a system, which includes a plurality of loads, a battery and the above power supply circuit; one end of the power supply circuit is connected with the battery, and the other end of the power supply circuit is respectively connected with a plurality of loads; the battery is used for providing voltage for the power supply circuit; the power supply circuit is used for providing working voltage for the plurality of loads. For the description of the power supply circuit, details of the embodiment of the present application are not repeated.

As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present application without departing from the scope of the application. Thus, if such modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is intended to include such modifications and variations as well.

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Power supply circuit, control method and system

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