CN115459411B

CN115459411B - Power supply device and terminal equipment

Info

Publication number: CN115459411B
Application number: CN202211401976.0A
Authority: CN
Inventors: 张立新
Original assignee: Honor Device Co Ltd
Current assignee: Honor Device Co Ltd
Priority date: 2022-11-10
Filing date: 2022-11-10
Publication date: 2023-05-09
Anticipated expiration: 2042-11-10
Also published as: CN115459411A

Abstract

The application provides a power supply device and terminal equipment, this power supply device can include: the power supply comprises a boosting unit, a first switch and a backlight power supply, wherein the boosting unit is used for boosting an electric signal input by an input end and outputting the boosted electric signal from a first output end; the input end of the boosting unit is used for being connected with a battery, the first output end of the boosting unit is connected with the first input end of a backlight power supply, the first output end of the backlight power supply is used for being connected with a light-emitting device, the first end of the first switch is connected with the input end of the boosting unit, and the second end of the first switch is connected with the first input end of the backlight power supply. The power supply device provided by the application flexibly switches the working state of the boosting unit through the opening and closing of the first switch so as to change the input voltage of the backlight power supply, and the power supply device can be suitable for different scenes and has higher flexibility.

Description

Power supply device and terminal equipment

Technical Field

The application relates to the technical field of terminals, in particular to a power supply device and terminal equipment.

Background

The backlight power supply in the terminal device is used for providing a light source for the display screen of the terminal device. The backlight power supply includes three output pins, which are AVDD pin, ELVDD pin, and ELVSS pin, respectively. The AVDD pin is a power pin for supplying power to the outside, and the output voltage is typically 7.6 volts (V). The ELVDD pin and the ELVSS pin may be collectively referred to as a power supply pin, an output voltage of the ELVDD pin is generally 4.6V, and an output voltage of the ELVSS pin is generally-2V to-4V.

Currently, the terminal device may use a battery to supply power to the backlight power through the charging chip. However, the input voltage of the backlight power supply is 3-4.3V, and the output of the backlight power supply is 7.6V, 4.6V or-2V, and the backlight power supply needs to adjust the input voltage to a voltage matched with the output pins (AVDD pin, ELVDD pin and ELVSS pin), so that the power consumption of the backlight power supply is larger and the efficiency is lower.

Therefore, there is a need for a power supply device that can improve the efficiency of the backlight power supply.

Disclosure of Invention

The application provides a power supply device and terminal equipment, can improve backlight power's efficiency.

In a first aspect, the present application provides a power supply device, including: the power supply comprises a boosting unit, a first switch and a backlight power supply, wherein the boosting unit is used for boosting an electric signal input by an input end and outputting the boosted electric signal from a first output end; the input end of the boosting unit is used for being connected with a battery, the first output end of the boosting unit is connected with the first input end of a backlight power supply, the first output end of the backlight power supply is used for being connected with a light-emitting device, the first end of the first switch is connected with the input end of the boosting unit, and the second end of the first switch is connected with the first input end of the backlight power supply.

The boosting unit may also be referred to as a boosting chip, which is not limited in this application. The voltage boosting unit is configured to boost an electric signal input from the input terminal and output the boosted electric signal from the first output terminal, and it is understood that the voltage boosting unit may boost an input voltage of the input terminal and output the boosted voltage.

The backlight power supply can be connected with the light-emitting device to supply power to the light-emitting device. Wherein the light emitting means may be a light emitting diode (light emitting diode, LED). The output voltage of the output terminal of the backlight power supply may be different according to the load, i.e., the light emitting device. The backlight power supply is configured to perform a first boosting process on the electric signal input from the first input terminal and output the boosted electric signal from the first output terminal, and it is understood that the backlight power supply may boost the input voltage of the input terminal and output the boosted voltage. It should be noted that, the first input terminal of the backlight power supply is used to represent an input pin of the backlight power supply, and may represent one or more input pins, which is not limited in this application.

Illustratively, the output pins of the backlight power source may include an AVDD pin, an ELVDD pin, and an ELVSS pin. The AVDD pin may be referred to as a power pin for supplying power to the outside. The ELVDD pin and the ELVSS pin may be collectively referred to as power supply pins. The first output may be an AVDD pin and/or an ELVDD pin.

The first end of the first switch is connected with the input end of the boosting unit, and the second end of the first switch is connected with the first input end of the backlight power supply, which can be understood as that the first switch is connected with the boosting unit in parallel. It will be appreciated that when the first switch is closed, the boost unit is shorted, i.e. the boost unit is not active. When the first switch is turned off, the boosting unit is turned on.

When the first switch is closed, the battery can directly supply power to the backlight power supply through the first switch; when the first switch is turned off, the battery may supply power to the backlight power source through the boosting unit.

Illustratively, the first switch may be switch a in fig. 4 in the embodiment, the backlight power source may be backlight power source 150 in fig. 4, and the battery may be battery 132 in fig. 4. When the switch a is closed, the boosting unit is shorted, and the battery 132 may transmit an electrical signal to the backlight power source 150 through the switch a by the power management module 131. When the switch is turned off, the boosting unit is turned on, and the battery 132 may transmit an electrical signal to the backlight power source 150 through the power management module 131.

When the first switch is closed, the input voltage of the backlight power supply is the output voltage of the battery; when the first switch is turned off, the boosting unit boosts an output voltage of the battery and outputs the boosted voltage to the backlight power supply.

The closing and opening of the first switch may be determined based on different factors.

In one possible example, the closing and opening of the first switch may be determined based on the remaining charge of the battery.

The first switch may be for: closing when the residual electric quantity of the battery is larger than or equal to a first preset electric quantity; and when the residual electric quantity of the battery is smaller than the first preset electric quantity, the battery is disconnected.

In another possible example, the closing and opening of the first switch may be determined based on the maximum voltage that the boost unit is capable of outputting.

The first switch may be for: closing when the output voltage of the battery is greater than or equal to the maximum voltage which can be output by the boosting unit; the battery is turned off when the output voltage of the battery is less than the maximum voltage that the boosting unit can output.

In yet another possible example, the closing and opening of the first switch may be determined based on the remaining amount of the battery and the maximum voltage that the boosting unit can output.

Closing when the residual electric quantity of the battery is larger than or equal to the first preset electric quantity or the output voltage of the battery is larger than or equal to the maximum voltage which can be output by the boosting unit; and when the residual electric quantity of the battery is smaller than the first preset electric quantity or the output voltage of the battery is smaller than the maximum voltage which can be output by the boosting unit, the power supply is disconnected.

Alternatively, the boost unit and the first switch may be packaged in different chips, or may be packaged in the same chip, which is not limited in this application.

Alternatively, the boost unit, the first switch and the backlight power supply are respectively packaged in different chips, and may also be packaged in the same chip, which is not limited in this application.

For example, the boosting unit, the first switch may be packaged in a chip containing the backlight power supply.

According to the power supply device, when the first switch is turned off, the input voltage of the backlight power supply is the voltage which is increased by the boosting unit, so that the pressure difference between the input voltage and the output voltage of the backlight power supply can be reduced, the power consumption of the backlight power supply is reduced, and the efficiency of the backlight power supply is improved; when the first switch is closed, the input voltage of the backlight power supply is the output voltage of the battery, and the working state of the boosting unit is flexibly switched through the opening and closing of the first switch so as to change the input voltage of the backlight power supply, so that the device is applicable to different scenes and has higher flexibility.

With reference to the first aspect, in certain implementation manners of the first aspect, the power supply device further includes a control unit, where the control unit is configured to: detecting the residual electric quantity of the battery; when the residual electric quantity of the battery is larger than or equal to the first preset electric quantity, the first switch is controlled to be closed; and when the residual electric quantity of the battery is smaller than the first preset electric quantity, controlling the first switch to be switched off.

The control unit may be a unit having a processing function. For example, the control unit may be the processor 110 shown in fig. 1 in the embodiment, but the present application is not limited thereto. The control unit may control the first switch to be closed or opened based on the remaining power of the battery.

Specifically, the control unit may detect the remaining capacity of the battery in real time or periodically. If the remaining power of the battery is greater than or equal to the first preset power, the power of the battery is sufficient, at this time, the control unit can control the first switch to be closed, the boost unit is short-circuited, and the output voltage of the backlight power supply is the output voltage of the battery. If the remaining capacity of the battery is smaller than the first preset capacity, the control unit can control the first switch to be turned off, the boosting unit can boost the output voltage of the battery, and the boosted voltage is output to the backlight power supply. The first preset power may be a lower power, for example: the first preset electrical quantity is 20% or 30%, or may be a higher electrical quantity, for example, the first preset electrical quantity is 60% or 70%, which is not limited in this application.

According to the power supply device, the control unit can control the first switch to be turned on or turned off according to the residual electric quantity of the battery, and when the residual electric quantity of the battery is smaller than the first preset electric quantity, the input voltage of the backlight power supply is increased through the boosting unit, so that the power consumption of the backlight power supply is reduced, the electric quantity consumption is saved, and the service time of the backlight power supply is prolonged; under the condition that the residual electric quantity of the battery is larger than or equal to the first preset electric quantity, the output voltage of the battery is used as the input voltage of the backlight power supply, the input voltage of the backlight power supply is flexibly changed, the method can be suitable for different scenes, and the flexibility is high.

With reference to the first aspect, in certain implementation manners of the first aspect, the power supply device further includes a control unit, where the control unit is configured to: detecting an output voltage of the battery; when the output voltage of the battery is greater than or equal to the maximum voltage which can be output by the boosting unit, the first switch is controlled to be closed.

The control unit may be a unit having a processing function. For example, the control unit may be the processor 110 shown in fig. 1 in the embodiment, but the present application is not limited thereto. The control unit may control the first switch to be closed or opened based on an output voltage of the battery and a maximum voltage that the boosting unit can output.

Specifically, the control unit may detect the output voltage of the battery in real time. If the output voltage of the battery is greater than or equal to the maximum voltage that the boost unit can output, the boost unit is not required to boost, at this time, the control unit can control the first switch to be closed, the boost unit is shorted, and the output voltage of the backlight power supply is the output voltage of the battery. If the output voltage of the battery is smaller than the maximum voltage which can be output by the boosting unit, the boosting unit can boost, at this time, the control unit can control the first switch to be turned off, the boosting unit can boost the output voltage of the battery, and the boosted voltage can be output to the backlight power supply. Wherein the maximum voltage that the boosting unit can output is related to the output voltage of the backlight power supply. The most output of the booster unit

The large voltage should be smaller than the output voltage of the backlight power supply. For example, the output voltage of the backlight power supply is 7.6V, and the maximum voltage that the boosting unit can output should be less than 7.6V. Alternatively, the output voltage of the backlight power supply is 4.6V, and the maximum voltage that the boosting unit can output should be less than 4.6V.

According to the power supply device, the control unit can control the first switch to be turned on or turned off according to the output voltage of the battery and the maximum voltage which can be output by the boost unit, and when the output voltage of the battery is smaller than the maximum voltage which can be output by the boost unit, the boost unit is used for boosting the input voltage of the backlight power supply, so that the power consumption of the backlight power supply is reduced, the electric quantity consumption is saved, and the service time of the backlight power supply is prolonged; under the condition that the output voltage of the battery is larger than or equal to the maximum voltage which can be output by the boosting unit, the output voltage of the battery is used as the input voltage of the backlight power supply, the input voltage of the backlight power supply is flexibly changed, the method can be suitable for different scenes, and the flexibility is high.

With reference to the first aspect, in some implementations of the first aspect, the backlight power supply is further configured to perform a second boosting process on the electrical signal input at the second input end and output the boosted electrical signal from the second output end; the electric signal input by the second input end of the backlight power supply and the electric signal input by the input end of the boosting unit are the same electric signal.

The backlight power supply may include a first input terminal and a second input terminal, and may perform a first boosting process on an electric signal input from the first input terminal and output a boosted electric signal from the first output terminal, and may perform a second boosting process on an electric signal input from the second input terminal and output a boosted electric signal from the second output terminal, where, however, the electric signal input from the first input terminal is an electric signal output by the boosting unit, and the electric signal input from the second input terminal is the same electric signal as the electric signal input from the input terminal of the boosting unit, that is, the electric signal output by the battery, that is, the voltage of the first input terminal of the backlight power supply may be the voltage boosted by the boosting unit, and the voltage of the second input terminal of the backlight power supply is the output voltage of the battery.

If the first output end of the backlight power supply is an AVDD pin, the second output end of the backlight power supply is an ELVDD pin. If the first output end of the backlight power supply is the ELVDD pin, the second output end of the backlight power supply is the AVDD pin.

Illustratively, the first output of the backlight power supply is an AVDD pin and the second output of the backlight power supply is an ELVDD pin. In the example shown in fig. 6 in the embodiment, the backlight power supply may be the backlight power supply 150, the first input terminal of the backlight power supply may be the input pin a of the backlight power supply 150, and the second input terminal of the backlight power supply may be the input pin b of the backlight power supply 150. The backlight power supply 150 may adjust the input voltage of the input pin a to the voltage output by the AVDD pin (i.e., the first output terminal), and the backlight power supply 150 may adjust the input voltage of the input pin b to the voltage output by the ELVDD pin (i.e., the second output terminal). The first switch may be switch B and the battery may be battery 132.

The power supply device that this application provided, the signal of telecommunication of backlight's first input and second input is different, when first switch disconnection, the voltage after the boost chip only exports the rising to backlight's first input, only reduces backlight's first output and first input's pressure differential, is favorable to reducing backlight's consumption, saves the electric quantity consumption, is favorable to prolonging backlight's live time.

With reference to the first aspect, in certain implementation manners of the first aspect, the boost unit is further configured to output the boosted electric signal from the second output terminal; the backlight power supply is also used for performing second boosting processing on the electric signal input by the second input end and outputting the boosted electric signal from the second output end; the second output end of the boosting unit is connected with the second input end of the backlight power supply; the power supply device further comprises a second switch, a first end of the second switch is connected with the input end of the boosting unit, and a second end of the second switch is connected with the second input end of the backlight power supply.

The backlight power supply may include a first input terminal and a second input terminal, the first input terminal of the backlight power supply being connected with the first output terminal of the boosting unit, and the second output terminal of the backlight power supply being connected with the second output terminal of the boosting unit.

The power supply device that this embodiment provided includes first switch and second switch, and the first end of first switch is connected with the input of unit that steps up, and the second end of first switch links to each other with the first input of backlight, and the first end of second switch is connected with the input of unit that steps up, and the second end of second switch links to each other with the second input of backlight.

It should be noted that this state of the first switch and the second switch is the same, i.e. both the first switch and the second switch are closed or both the first switch and the second switch are open.

When both the first switch and the second switch are closed, the boost unit is shorted. When the first switch and the second switch are both disconnected, the boosting unit is communicated.

Illustratively, in the example shown in fig. 8 in the embodiment, the backlight power source is a backlight power source 150. The first input end of the backlight power supply may be an input pin a of the backlight power supply 150, the second input end of the backlight power supply may be an input pin b of the backlight power supply 150, the first output end of the backlight power supply may be an AVDD pin of the backlight power supply 150, and the second output end of the backlight power supply may be an ELVDD pin of the backlight power supply 150. If the first switch is switch C, the second switch may be switch D; if the first switch is switch D, the second switch may be switch C. The first switch is taken as a switch C, and the second switch is taken as a switch D for example.

When both the switch C and the switch D are closed, the boosting unit is short-circuited, the voltages of the input pin a and the input pin b of the backlight power supply 150 are both the output voltages of the battery, the backlight power supply 150 performs a first boosting process on the output voltage of the battery and outputs a boosted electric signal from the AVDD pin, and performs a second boosting process on the output voltage of the battery and outputs a boosted electric signal from the ELVDD pin.

When the switch C and the switch D are both turned off, the boosting unit is connected, the voltages of the input pin a and the input pin b of the backlight power supply 150 are both voltages output by the boosting power supply, the backlight power supply 150 performs a first boosting process on the voltage output by the boosting power supply and outputs a boosted electric signal from the AVDD pin, and performs a second boosting process on the voltage output by the boosting power supply and outputs a boosted electric signal from the ELVDD pin.

According to the power supply device, when the first switch and the second switch are disconnected, the input voltage of the backlight power supply is the voltage which is increased by the boosting unit, so that the pressure difference between the input voltage and the output voltage of the backlight power supply can be reduced, the power consumption of the backlight power supply is reduced, and the efficiency of the backlight power supply is improved; when the first switch and the second switch are closed, the input voltage of the backlight power supply is the output voltage of the battery, and the working state of the boosting unit is flexibly switched through the opening and closing of the first switch so as to change the input voltage of the backlight power supply, so that the device can be suitable for different scenes and has higher flexibility.

With reference to the first aspect, in certain implementation manners of the first aspect, the power supply device further includes a control unit, where the control unit is configured to: detecting the residual electric quantity of the battery; when the residual electric quantity of the battery is larger than or equal to the second preset electric quantity, the first switch and the second switch are controlled to be closed; and when the residual electric quantity of the battery is smaller than the second preset electric quantity, the first switch and the second switch are controlled to be disconnected.

The control unit may be a unit having a processing function. For example, the control unit may be the processor 110 shown in fig. 1 in the embodiment, but the present application is not limited thereto. The control unit may control the first switch and the second switch to be closed or opened based on a remaining amount of the battery.

Specifically, the control unit may detect the remaining capacity of the battery in real time or periodically. If the remaining power of the battery is greater than or equal to the second preset power, the power of the battery is sufficient, at this time, the control unit can control the first switch and the second switch to be closed, the boost unit is short-circuited, and the output voltage of the backlight power supply is the output voltage of the battery. If the remaining capacity of the battery is smaller than the first preset capacity, the control unit can control the first switch and the second switch to be switched off, the boosting unit can boost the output voltage of the battery, and the boosted voltage is output to the backlight power supply. The second preset electric quantity may be the same as or different from the first preset electric quantity, which is not limited in the present application.

If the second preset power is different from the first preset power, the second preset power may be lower than the first preset power when the first preset power is a lower power. When the first preset power is a higher power, the second preset power may be higher than the first preset power.

For example, if the first preset electrical quantity is 20%, the second preset electrical quantity may be 15%. If the first preset power is 60%, the second preset power may be 70%.

According to the power supply device, the control unit can control the first switch and the second switch to be closed or opened according to the residual electric quantity of the battery, and when the residual electric quantity of the battery is smaller than the second preset electric quantity, the boosting unit is used for boosting the input voltage of the backlight power supply, so that the power consumption of the backlight power supply is reduced, the electric quantity consumption is saved, and the service time of the backlight power supply is prolonged; under the condition that the residual electric quantity of the battery is larger than or equal to the second preset electric quantity, the output voltage of the battery is used as the input voltage of the backlight power supply, the input voltage of the backlight power supply is flexibly changed, the method can be suitable for different scenes, and the flexibility is high.

With reference to the first aspect, in certain implementation manners of the first aspect, the power supply device further includes a control unit, where the control unit is configured to: detecting an output voltage of the battery; when the output voltage of the battery is greater than or equal to the maximum voltage which can be output by the boosting unit, the first switch and the second switch are controlled to be closed.

Specifically, the control unit may detect the output voltage of the battery in real time. If the output voltage of the battery is greater than or equal to the maximum voltage that the boost unit can output, the boost unit is not required to boost, at this time, the control unit can control the first switch and the second switch to be closed, the boost unit is shorted, and the output voltage of the backlight power supply is the output voltage of the battery. If the output voltage of the battery is smaller than the maximum voltage which can be output by the boosting unit, the boosting unit can boost, at this time, the control unit can control the first switch and the second switch to be turned off, the boosting unit can boost the output voltage of the battery, and the boosted voltage can be output to the backlight power supply. Wherein the maximum voltage that the boosting unit can output is related to the output voltage of the backlight power supply. The maximum voltage that the boost unit can output should be less than the output voltage of the backlight power supply.

When the power supply device includes the first switch, the maximum voltage that the booster unit can output is different from when the power supply device includes the first switch and the second switch.

According to the power supply device, the control unit can control the first switch and the second switch to be closed or opened according to the output voltage of the battery and the maximum voltage which can be output by the boost unit, and when the output voltage of the battery is smaller than the maximum voltage which can be output by the boost unit, the boost unit is used for boosting the input voltage of the backlight power supply, so that the power consumption of the backlight power supply is reduced, the electric quantity consumption is saved, and the service time of the backlight power supply is prolonged; under the condition that the output voltage of the battery is larger than or equal to the maximum voltage which can be output by the boosting unit, the output voltage of the battery is used as the input voltage of the backlight power supply, the input voltage of the backlight power supply is flexibly changed, the method can be suitable for different scenes, and the flexibility is high.

With reference to the first aspect, in certain implementations of the first aspect, a boost ratio of the first boost process is greater than a boost ratio of the second boost process.

The ratio of the voltage of the first output end of the backlight power supply to the voltage of the first input end of the backlight power supply is the boosting ratio of the first boosting process, and the ratio of the voltage of the second output end of the backlight power supply to the voltage of the second input end of the backlight power supply is the boosting ratio of the second boosting process.

The voltage of the first input end of the backlight power supply is the same as the voltage of the second input end of the backlight power supply, the boosting ratio of the first boosting process is larger than that of the second boosting process, and it can be stated that the voltage of the first output end of the backlight power supply is larger than that of the second output end of the backlight power supply. The first output of the backlight power supply may be an AVDD pin and the second output of the backlight power supply may be an ELVDD pin.

With reference to the first aspect, in certain implementations of the first aspect, the backlight power supply is further configured to: step-down processing is carried out on the electric signal input by the third input end, and the electric signal after step-down is output from the third output end; the electric signal input by the third input end of the backlight power supply and the electric signal input by the input end of the boosting unit are the same.

The voltage of the third input end of the backlight power supply is the output voltage of the battery. The backlight power supply may step down the output voltage of the battery and output the stepped-down electrical signal from the third output terminal.

Illustratively, in the example shown in fig. 4 in the embodiment, the third input terminal of the backlight power supply is the input pin c, and the third output terminal of the backlight power supply is the ELVSS pin.

In a second aspect, the present application provides a terminal device, including: a battery, a light emitting device and a power supply device in any one of the possible implementations of the first aspect.

Drawings

Fig. 1 is a schematic structural view of a terminal device;

FIG. 2 is a schematic diagram of a backlight power supply;

fig. 3 is a schematic diagram of a power supply device according to an embodiment of the present application;

fig. 4 is a schematic diagram of another power supply device according to an embodiment of the present disclosure;

fig. 5 is a schematic view of yet another power supply device according to an embodiment of the present disclosure;

FIG. 6 is a schematic diagram of another power supply device according to an embodiment of the present disclosure;

fig. 7 is a schematic view of yet another power supply device according to an embodiment of the present disclosure;

fig. 8 is a schematic diagram of another power supply device according to an embodiment of the present disclosure;

fig. 9 is a simulation diagram provided in an embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be described below with reference to the accompanying drawings.

In order to clearly describe the technical solutions of the embodiments of the present application, in the embodiments of the present application, the words "first", "second", etc. are used to distinguish the same item or similar items having substantially the same function and effect. It will be appreciated by those of skill in the art that the words "first," "second," and the like do not limit the amount and order of execution, and that the words "first," "second," and the like do not necessarily differ.

In this application, the terms "exemplary" or "such as" are used to mean serving as an example, instance, or illustration. Any embodiment or design described herein as "exemplary" or "for example" should not be construed as preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary" or "such as" is intended to present related concepts in a concrete fashion.

Furthermore, "at least one" means one or more, and "a plurality" means two or more. "and/or", describes an association relationship of an association object, and indicates that there may be three relationships, for example, a and/or B, and may indicate: a alone, a and B together, and B alone, wherein a, B may be singular or plural. The character "/" generally indicates that the context-dependent object is an "or" relationship. "at least one of" or the like means any combination of these items, including any combination of single item(s) or plural items(s). For example, at least one (one) of a, b, and c may represent: a, b, or c, or a and b, or a and c, or b and c, or a, b and c, wherein a, b and c can be single or multiple.

The technical scheme provided by the embodiment of the application can be applied to any terminal equipment comprising a display screen. For example, wearable terminal devices such as a mobile phone, a tablet PC, a personal computer (personal computer, PC), and a smart watch may be various teaching aids (e.g., learning machine, early education machine), smart toys, portable robots, personal digital assistants (personal digital assistant, PDA), augmented reality (augmented reality, AR) devices, virtual Reality (VR) devices, etc., devices with mobile office functions, devices with smart home functions, devices with video and audio entertainment functions, devices supporting smart travel, etc.

In order to better understand the embodiments of the present application, the following describes the hardware structure of the terminal device in the embodiments of the present application.

Fig. 1 shows a schematic diagram of a terminal device. As shown in fig. 1, the terminal device may include a processor 110, a universal serial bus (universal serial bus, USB) interface 120, a charge management module 130, a power management module 131, a battery 132, a display 14, a backlight power supply 150, and the like.

It is to be understood that the structure illustrated in the embodiments of the present application does not constitute a specific limitation on the terminal device. In other embodiments of the present application, the terminal device may include more or less components than illustrated, or certain components may be combined, or certain components may be split, or different arrangements of components. The illustrated components may be implemented in hardware, software, or a combination of software and hardware.

The processor 110 may include one or more processing units, such as: the processor 110 may include an application processor (application processor, AP), a modem processor, a graphics processor (graphics processing unit, GPU), an image signal processor (image signal processor, ISP), a controller, a video codec, a digital signal processor (digital signal processor, DSP), a baseband processor, and/or a neural network processor (neural-network processing unit, NPU), etc. Wherein the different processing units may be separate devices or may be integrated in one or more processors. The controller in the processor 110 may generate operation control signals according to the instruction operation code and the timing signals to complete instruction fetching and instruction execution control.

A memory may also be provided in the processor 110 for storing instructions and data. In some embodiments, the memory in the processor 110 is a cache memory. The memory may hold instructions or data that the processor 110 has just used or recycled. If the processor 110 needs to reuse the instruction or data, it may be called from memory. Repeated accesses are avoided and the latency of the processor 110 is reduced, thereby improving the efficiency of the system.

In some embodiments, the processor 110 may include one or more interfaces. The interfaces may include an integrated circuit (inter-integrated circuit, I2C) interface, an integrated circuit built-in audio (inter-integrated circuit sound, I2S) interface, a pulse code modulation (pulse code modulation, PCM) interface, a universal asynchronous receiver transmitter (universal asynchronous receiver/transmitter, UART) interface, a mobile industry processor interface (mobile industry processor interface, MIPI), a general-purpose input/output (GPIO) interface, a subscriber identity module (subscriber identity module, SIM) interface, and/or a universal serial bus (universal serial bus, USB) interface, among others.

USB interface 120 is an interface conforming to the USB standard specification, and may specifically be a Mini USB interface, a Micro USB interface, a USB Type C interface, or the like. The USB interface 120 may be used to connect a charger to charge a terminal device, or may be used to transfer data between the terminal device and a peripheral device. And can also be used for connecting with a headset, and playing audio through the headset. The interface may also be used to connect other terminal devices, such as AR devices, etc.

It will be understood that the interfacing relationship between the modules illustrated in the embodiments of the present application is a schematic illustration, and does not constitute a structural limitation of the terminal device. In other embodiments of the present application, the terminal device may also use different interfacing manners in the foregoing embodiments, or a combination of multiple interfacing manners.

The charge management module 130 is configured to receive a charge input from a charger. The charger can be a wireless charger or a wired charger. In some wired charging embodiments, the charge management module 130 may receive a charging input of a wired charger through the USB interface 120. In some wireless charging embodiments, the charging management module 130 may receive wireless charging input through a wireless charging coil of the terminal device. The charging management module 130 may also supply power to the terminal device through the power management module 131 while charging the battery 132.

The power management module 131 is used for connecting the battery 132, and the charge management module 130 and the processor 110. The power management module 131 receives input from the battery 132 and/or the charge management module 130 to power the processor 110, the display screen 140, the backlight power supply 150, and the like. The power management module 131 may also be configured to monitor battery capacity, battery cycle number, battery health (leakage, impedance) and other parameters. In other embodiments, the power management module 131 may also be disposed in the processor 110. In other embodiments, the power management module 131 and the charging management module 130 may also be disposed in the same device.

The battery 132 may be a rechargeable lithium battery, or other rechargeable battery, as embodiments of the present application are not limited in this regard.

The display screen 140 is used for displaying images, displaying videos, receiving sliding operations, and the like. The display screen 140 includes a display panel. The display panel may employ a liquid crystal display (liquid crystal display, LCD), an organic light-emitting diode (OLED), an active-matrix organic light emitting diod (AMOLED), a flexible light-emitting diode (flex), a mini, a Micro-OLED, a quantum dot light-emitting diode (quantum dot light emitting diodes, QLED), or the like. In some embodiments, the terminal device may include 1 or N display screens 194, N being a positive integer greater than 1.

The backlight power supply 150 is used to power the display screen 140. Fig. 2 shows a schematic diagram of a configuration of a backlight power supply 150. As shown in fig. 2, the backlight power supply 150 may include a boost module 1, a buck-boost module, and a boost module 2. The boost modules 1 and 2 are used to boost the input voltage. The buck-boost module may be used to boost the input voltage or to buck the input voltage. The input pin of the boost module 1 is an LX1 pin, and the output pin of the boost module 1 is an ELVDD pin. The input pins of the buck-boost module comprise a PVIN2A pin, a PVIN2B pin, an LX2A pin and an LX2B pin, and the output pin of the buck-boost module is an ELVSS pin. The input pin of the boost module 2 is an LX3 pin, and the output pin of the boost module 2 is an AVDD pin. Among other things, the AVDD pin may be referred to as a power pin for supplying power out, with an output voltage of typically 7.6 volts (V). The ELVDD pin and the ELVSS pin may be collectively referred to as a power supply pin, an output voltage of the ELVDD pin is generally 4.6V, and an output voltage of the ELVSS pin is generally-2V to-4V. The backlight power supply 150 has LX1 pin, PVIN2A pin, PVIN2B pin, LX2A pin, LX2B pin, and LX3 pin connected to the battery management module 131.

In the terminal device shown in fig. 1, the battery 132 may supply power to the backlight power supply 150 through the power management module 131 (may also be referred to as a charging chip), but the input voltage of the backlight power supply 150 is 3-4.3V, and the output of the backlight power supply 150 is 7.6V, 4.6V or-2V, and the backlight power supply 150 needs to adjust the input voltage (i.e. the voltages corresponding to the LX1 pin, the PVIN2A pin, the PVIN2B pin, the LX2A pin, the LX2B pin and the LX3 pin of the backlight power supply 150) to the voltage matched with the output pins (AVDD pin, ELVDD pin and ELVSS pin), which results in greater power consumption and lower efficiency of the backlight power supply 150.

In view of this, the embodiments of the present application provide a power supply device and a terminal device, which reduce the difference between the output voltage and the input voltage of the backlight power supply by increasing the input voltage of the backlight power supply, thereby reducing the power consumption of the backlight power supply, and being beneficial to improving the efficiency of the backlight power supply.

In this embodiment, the power supply device provided in this embodiment of the present application is described in detail by taking the terminal device shown in fig. 1 as an example.

Fig. 3 shows a schematic diagram of a power supply device according to an embodiment of the present application. As shown in fig. 3, the boost unit is connected to the power management module 131 and the backlight power source 150, and the battery 132 is connected to the power management module 131 to supply power to the backlight power source 150. The boosting unit may be used to boost the input voltage. The boosting unit may be any chip having a boosting voltage function.

The voltage output by the battery 132 through the power management module 131 may be represented by VPH-PWR, and the voltage value range of VPH-PWR may be 3-4.3 v. The input voltage of the boosting unit is VPH-PWR. The boosting unit may boost the input voltage VPH-PWR and output the boosted voltage to the backlight power supply 150. The backlight power supply 150 adjusts the boosted voltage to a voltage matched to the output pins (AVDD pin, ELVDD pin, and ELVSS pin).

In this case, the voltages of the input pins (i.e., LX1 pin, PVIN2A pin, PVIN2B pin, LX2A pin, LX2B pin, and LX3 pin) of the backlight power supply 150 are all the increased voltages, and the difference between the voltage of the output pin and the voltage of the input pin of the backlight power supply 150 can reduce the power consumption of the backlight power supply 150 before the voltage is increased by the voltage increasing unit, which is advantageous for improving the efficiency of the backlight power supply 150.

Alternatively, the voltage output from the boosting unit may be less than the voltage of the ELVDD pin. For example, the voltage output by the boosting unit may be less than 4.6V.

The embodiment of the application also provides a power supply device, which can freely switch the input voltage of the backlight power supply 150.

Fig. 4 shows a schematic diagram of another power supply device according to an embodiment of the present application. As shown in fig. 4, the boosting unit is connected to the power management module 131 and the backlight power source 150, respectively, and is connected in parallel to a switch a. When the switch a is closed, the boost unit is shorted; when switch a is open, the boost unit may operate. The battery 132 is connected to the power management module 131 and can supply power to the backlight power source 150.

The closing and opening of switch a may be determined based on different factors.

In one possible example, the closing and opening of switch a may be determined based on the remaining charge of battery 132.

Switch a may be used to: closing when the remaining capacity of the battery 132 is greater than or equal to a first preset capacity; and is turned off when the remaining capacity of the battery 132 is less than the first preset capacity. The first preset power may be a lower power, for example: the first preset electrical quantity is 20% or 30%, or may be a higher electrical quantity, for example, the first preset electrical quantity is 60% or 70%, which is not limited in the embodiment of the present application.

The switch a is used to be closed when the remaining capacity of the battery 132 is greater than or equal to a first preset capacity, and is used to be opened when the remaining capacity of the battery 132 is less than the first preset capacity. When the remaining power of the battery 132 is greater than or equal to the first preset power, the switch a is closed, the boost unit is shorted, and the input voltage of the backlight power source 150 is the voltage VPH-PWR output by the battery 132 through the power management module 131. When the remaining capacity of the battery 132 is less than the first preset capacity, the switch a is turned off, and the boosting unit is used to boost VPH-PWR and output the boosted voltage to the backlight power supply 150.

In this implementation manner, the terminal device may determine, according to the remaining power of the battery 132, whether the switch a is turned on or off, so as to flexibly change the input voltage of the backlight power supply 150, which is beneficial to reducing the power consumption of the backlight power supply 150 under different conditions, and further is beneficial to improving the efficiency of the backlight power supply 150.

In another possible example, the closing and opening of switch a may be determined based on the maximum voltage that the boost unit is capable of outputting.

Switch a may be used to: closing when the output voltage of the battery 132 is greater than or equal to the maximum voltage that the boosting unit can output; the switch is turned off when the output voltage of the battery 132 is smaller than the maximum voltage that the boosting unit can output.

The voltage output by the battery 132 through the power management module 131 is VPH-PWR. Switch a is used to close when VPH-PWR is greater than or equal to the maximum voltage that the boost unit can output, and to open when VPH-PWR is less than the maximum voltage that the boost unit can output. When VPH-PWR is greater than or equal to the maximum voltage that the boosting unit can output, switch a is closed, the boosting unit is shorted, and the input voltage of backlight power supply 150 is VPH-PWR. When VPH-PWR is smaller than the maximum voltage that can be output by the boosting unit, switch a is turned off, and the boosting unit is used to boost VPH-PWR and output the boosted voltage to backlight power supply 150.

In this implementation manner, the terminal device may determine, according to the voltage value output by the battery 132 through the power management module 131, whether the switch a is turned on or turned off, so as to flexibly change the input voltage of the backlight power supply 150, which is beneficial to reducing the power consumption of the backlight power supply 150 under different conditions, and further is beneficial to improving the efficiency of the backlight power supply 150.

In yet another possible example, the closing and opening of switch a may be determined based on the remaining charge of battery 132 and the maximum voltage that the boost unit is capable of outputting.

Closing when the remaining capacity of the battery 132 is greater than or equal to a first preset capacity, or the output voltage of the battery 132 is greater than or equal to the maximum voltage that the boosting unit can output; the switch is turned off when the remaining capacity of the battery 132 is smaller than the first preset capacity, or the output voltage of the battery 132 is smaller than the maximum voltage that the boosting unit can output.

Fig. 5 shows a schematic diagram of a power supply device according to an embodiment of the present application. As shown in fig. 5, the boosting unit is connected to the power management module 131 and the input pin a of the backlight power supply 150, respectively, and the power management module 131 is connected to the input pin b and the input pin c of the backlight power supply 150, respectively. The battery 132 is connected to the power management module 131 and can supply power to the backlight power source 150. The input pin a of the backlight power supply 150 is an input pin corresponding to the AVDD pin, and may be an LX3 pin; the input pin b of the backlight power supply 150 is an input pin corresponding to the ELVDD pin, and may be an LX1 pin; the input pin c of the backlight power supply 150 is an input pin corresponding to the ELVSS pin, and may include a PVIN2A pin, a PVIN2B pin, an LX2A pin, and an LX2B pin.

The voltage output from the battery 132 through the power management module 131 may be VPH-PWR, and the input voltage of the boosting unit is VPH-PWR, and the voltages of the input pin b and the input pin c of the backlight power source 150 are VPH-PWR. The boosting unit may boost the input voltage VPH-PWR and output the boosted voltage to the input pin a of the backlight power supply 150. The backlight power supply 150 may adjust the boosted voltage to a voltage matching the AVDD pin and adjust VPH-PWR to a voltage matching the ELVDD pin and the ELVSS pin.

In this case, the voltage of the input pin a of the backlight power supply 150 is the boosted voltage, and the voltage difference between the voltage of the input pin a and the AVDD pin is smaller than the voltage difference before the voltage boosting unit does not boost the voltage, so that the power consumption of the backlight power supply 150 can be reduced, which is beneficial to improving the efficiency of the backlight power supply 150.

Alternatively, the voltage output by the boosting unit may be smaller than the voltage of the AVDD pin. For example, the voltage output by the boosting unit may be less than 7.6V.

The embodiment of the present application also provides a power supply device, which can freely switch the input voltage of the input pin a of the backlight power supply 150.

Fig. 6 is a schematic diagram of a power supply device according to an embodiment of the present application. As shown in fig. 6, the boosting units are connected to the power management module 131 and the input pin a of the backlight power source 150, respectively, and are connected in parallel to the switch B. When switch B is closed, the boost unit is shorted; when switch B is open, the boost unit may operate. The power management module 131 is connected to the input pin b and the input pin c of the backlight power source 150, respectively. The battery 132 is connected to the power management module 131 and can supply power to the backlight power source 150. The switch B may be used to be closed when the remaining capacity of the battery 132 is greater than or equal to a first preset capacity, and to be opened when the remaining capacity of the battery 132 is less than the first preset capacity. Alternatively, switch B may be used to: closing when the output voltage of the battery 132 is greater than or equal to the maximum voltage that the boosting unit can output; the switch is turned off when the output voltage of the battery 132 is smaller than the maximum voltage that the boosting unit can output.

The voltage output by the battery 132 through the power management module 131 may be VPH-PWR. When switch B is closed, the boost unit is shorted, and the input voltages at input pin a, input pin B, and input pin c of backlight power supply 150 are VPH-PWR. When the switch B is turned off, the boosting unit is used to boost VPH-PWR and output the boosted voltage to the input pin a of the backlight power supply 150. The backlight power supply 150 may adjust the boosted voltage to a voltage matching the AVDD pin and adjust VPH-PWR to a voltage matching the ELVDD pin and the ELVSS pin.

By the implementation mode, the pressure difference between the input pin a and the AVDD pin of the backlight power supply can be reduced, the power consumption of the backlight power supply can be reduced, the electric quantity consumption can be saved, and the service time of the backlight power supply can be prolonged.

Fig. 7 shows a schematic diagram of a power supply device according to an embodiment of the present application. As shown in fig. 7, the boosting unit is connected to the power management module 131, the input pin a of the backlight power supply 150, and the input pin b of the backlight power supply 150, respectively, and the power management module 131 is connected to the input pin c of the backlight power supply 150. The battery 132 is connected to the power management module 131 and can supply power to the backlight power source 150.

The voltage output by the battery 132 through the power management module 131 may be VPH-PWR, and the input voltage of the boosting unit is VPH-PWR, and the voltage of the input pin c of the backlight power supply 150 is VPH-PWR. The boosting unit may boost the input voltage VPH-PWR and output the boosted voltage to the input pin a of the backlight power supply 150. The backlight power supply 150 may adjust the boosted voltage to a voltage matching the AVDD pin and the ELVDD pin and adjust VPH-PWR to a voltage matching the ELVSS pin.

In this case, the voltages of the input pin a and the input pin b of the backlight power supply 150 are the boosted voltages, the voltage difference between the voltage of the input pin a and the AVDD pin is smaller than the voltage difference before the boosting unit does not boost the voltage, the voltage difference between the voltage of the input pin b and the ELVDD pin is smaller than the voltage difference before the boosting unit does not boost the voltage, and thus the power consumption of the backlight power supply 150 can be reduced, which is advantageous for improving the efficiency of the backlight power supply 150.

The embodiment of the present application also provides a power supply device, which can freely switch the input voltages of the input pin a and the input pin b of the backlight power supply 150.

Fig. 8 is a schematic diagram of a power supply device according to an embodiment of the present application. As shown in fig. 8, the boost unit is connected to the power management module 131, the input pin a of the backlight power supply 150, and the input pin b of the backlight power supply 150, respectively, and connects the switch C and the switch D in parallel. When at least one of the switch C and the switch D is closed, the boosting unit is short-circuited; when both switch C and switch D are open, the boost unit may operate. The power management module 131 is connected to the input pin c of the backlight power source 150. The battery 132 is connected to the power management module 131 and can supply power to the backlight power source 150.

In this example, the states of the switch C and the switch D are the same, that is, the switch C and the switch D are both closed or both open, and there is no case where the switch C is closed and the switch D is open, or the switch C is open and the switch D is closed.

If the switch C and the switch D are both turned off, the input voltages of the input pin a and the input pin b of the backlight power supply 150 are the voltages boosted by the boosting unit. When both the switch C and the switch D are turned off, the power consumption of the backlight power supply 150 that can be reduced by the power supply device shown in fig. 8 is the same as that can be reduced by the power supply device shown in fig. 7 described above.

If both the switch C and the switch D are closed, the boost unit is shorted, and the input voltages of the input pin a, the input pin b, and the input voltage C of the backlight power supply 150 are the voltages VPH-PWR output from the battery 132 through the power management module 131.

The states of the switch C and the switch D may be determined according to the remaining amount of the battery 132 or according to the maximum voltage that the boosting unit can output.

In one possible implementation, the state of switch C and switch D may be determined based on the remaining charge of battery 132.

Illustratively, the switches C and D may be used to close when the remaining capacity of the battery 132 is greater than or equal to a second preset capacity, and to open when the remaining capacity of the battery 132 is less than the second preset capacity. The second preset electric quantity may be the same as or different from the first preset electric quantity, which is not limited in the present application.

If the voltage of the battery 132 is greater than or equal to the second preset power, it may be indicated that the remaining power of the battery 132 is sufficient, and at this time, the switch C and the switch D are both closed, the boost unit is shorted, and the voltages of the input pin a, the input pin b, and the input pin C of the backlight power supply 150 are VPH-PWR. If the voltage of the battery 132 is smaller than the second preset power, it may be indicated that the remaining power of the battery 132 is insufficient, and at this time, the switch C and the switch D are both turned off, and the boost unit is configured to boost VPH-PWR and output the boosted voltage to the input pin a and the input pin b of the backlight power supply 150, so as to reduce the voltage difference between the input pin a and the AVDD pin and the voltage difference between the input pin b and the ELVDD pin.

In this implementation manner, the terminal device may determine, according to the remaining power of the battery 132, whether the switch C and the switch D are turned on or off, so as to flexibly change the input voltages of different input pins of the backlight power supply 150, which is beneficial to reducing the power consumption of the backlight power supply 150 and further beneficial to improving the efficiency of the backlight power supply 150 under the condition that the remaining power of the battery 132 is insufficient.

In another possible implementation, the states of switch C and switch D may be determined according to the maximum voltage that the boost unit is capable of outputting. The maximum voltage that the boosting unit can output may be a maximum voltage value that the boosting unit can boost. For example, the maximum voltage that the boosting unit can output is 4V, 4.3V, 4.6V, or the like.

Illustratively, the switches C and D may be configured to be closed when the input voltage VPH-PWR of the boosting unit is greater than or equal to the maximum voltage that the boosting unit can output, and configured to be opened when the input voltage VPH-PWR of the boosting unit is less than the maximum voltage that the boosting unit can output.

If the input voltage VPH-PWR of the boosting unit is greater than or equal to the maximum voltage that the boosting unit can output, it can be stated that the boosting unit does not need to boost, at this time, the switch C and the switch D are both closed, the boosting unit is shorted, and the voltages of the input pin a, the input pin b, and the input pin C of the backlight power supply 150 are VPH-PWR. If the input voltage VPH-PWR of the boosting unit is smaller than the maximum voltage that the boosting unit can output, it may be explained that the boosting unit can boost, and at this time, the switch C and the switch D are both turned off, and the boosting unit is configured to boost VPH-PWR and output the boosted voltage to the input pin a and the input pin b of the backlight power supply 150, so as to reduce the voltage difference between the input pin a and the AVDD pin and the voltage difference between the input pin b and the ELVDD pin.

In this implementation manner, the terminal device may determine, according to the voltage value output by the battery 132 through the power management module 131, whether the switch C and the switch D are turned on or turned off, so as to flexibly change the input voltage of the backlight power supply 150, which is beneficial to reducing the power consumption of the backlight power supply 150 under different conditions, and further is beneficial to improving the efficiency of the backlight power supply 150.

In order to verify that the power supply device provided in the embodiment of the present application improves the efficiency of the backlight power supply, the embodiment of the present application simulates the power supply device shown in fig. 5.

Illustratively, fig. 9 shows a simulation diagram. As shown in fig. 9, in the example shown in fig. 5, the input voltages provided by the input pin a of the backlight power supply according to the embodiment of the present application are 2.5V, 3.3V, 3.8V, 4.35V, and 4.8V, respectively. As can be seen from the figure, the higher the voltage of the input pin a of the backlight power supply, the higher the efficiency of the backlight power supply. According to the power supply device provided by the embodiment of the application, the input voltage of the backlight power supply is improved through the boosting unit, and the efficiency of the backlight power supply can be improved.

The embodiment of the application also provides a terminal device, which can comprise a battery, a light-emitting device and any power supply device.

Those of ordinary skill in the art will appreciate that the various illustrative modules and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

It will be clearly understood by those skilled in the art that, for convenience and brevity of description, specific working procedures of the above-described system, apparatus and module may refer to corresponding procedures in the foregoing method embodiments, which are not repeated herein.

In the several embodiments provided in this application, it should be understood that the disclosed systems, devices, and methods may be implemented in other manners. For example, the apparatus embodiments described above are merely illustrative, and for example, the division of the modules is merely a logical function division, and there may be additional divisions when actually implemented, for example, multiple modules or components may be combined or integrated into another system, or some features may be omitted or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices or modules, which may be in electrical, mechanical, or other forms.

The modules described as separate components may or may not be physically separate, and components shown as modules may or may not be physical modules, i.e., may be located in one place, or may be distributed over a plurality of network modules. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional module in each embodiment of the present application may be integrated into one processing module, or each module may exist alone physically, or two or more modules may be integrated into one module.

The functions, if implemented in the form of software functional modules and sold or used as a stand-alone product, may be stored in a computer-readable storage medium. Based on such understanding, the technical solution of the present application may be embodied essentially or in a part contributing to the prior art or in a part of the technical solution, in the form of a software product stored in a storage medium, including several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in the embodiments of the present application. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a read-only memory (ROM), a random access memory (random access memory, RAM), a magnetic disk, or an optical disk, or other various media capable of storing program codes.

The foregoing is merely specific embodiments of the present application, but the scope of the embodiments of the present application is not limited thereto, and any person skilled in the art may easily think about changes or substitutions within the technical scope of the embodiments of the present application, and the changes or substitutions are intended to be covered by the scope of the embodiments of the present application. Therefore, the protection scope of the embodiments of the present application shall be subject to the protection scope of the claims.

Claims

1. A power supply device, characterized by comprising: the device comprises a boosting unit, a first switch, a second switch and a backlight power supply, wherein the boosting unit is used for boosting an electric signal input by an input end and outputting the boosted electric signal from a first output end, and is also used for outputting the boosted electric signal from a second output end;

the power supply management module is connected with the battery, a first output end of the boosting unit is connected with a first input end of the backlight power supply, a second output end of the boosting unit is connected with a second input end of the backlight power supply, the first output end of the backlight power supply is used for being connected with a light emitting device, a first end of the first switch is connected with the input end of the boosting unit, a second end of the first switch is connected with the first input end of the backlight power supply, a first end of the second switch is connected with the input end of the boosting unit, a second end of the second switch is connected with the second input end of the backlight power supply, the first output end of the backlight power supply is an AVDD pin, and the second output end of the backlight power supply is an ELVDD pin;

The power supply device further comprises a control unit for:

detecting the residual electric quantity of the battery;

when the residual electric quantity of the battery is larger than or equal to a second preset electric quantity, the first switch and the second switch are controlled to be closed;

when the residual electric quantity of the battery is smaller than the second preset electric quantity, the first switch and the second switch are controlled to be disconnected;

alternatively, the control unit is configured to:

detecting an output voltage of the battery;

and when the output voltage of the battery is larger than or equal to the maximum voltage which can be output by the boosting unit, controlling the first switch and the second switch to be closed.

2. The power supply of claim 1, wherein the backlight power supply is further configured to: step-down processing is carried out on the electric signal input by the third input end, and the electric signal after step-down is output from the third output end;

the electric signal input by the third input end of the backlight power supply and the electric signal input by the input end of the boosting unit are the same electric signal.

3. A terminal device, comprising: battery, light emitting device and power supply device according to any one of claims 1 to 2.