CN208174340U - The power supply circuit and electronic product of portable electronic product with OTG function - Google Patents

Abstract

The utility model discloses a power supply circuit of a portable electronic product with an OTG function and the electronic product, comprising an interface, a first battery, a second battery, a charging chip, a boost circuit and an application processor; the interface is used for externally connecting the OTG The device or charger includes a power supply pin and a detection pin; the power input terminal of the charging chip is connected to the power supply pin through the first switch, one of the power output terminals is connected to the first battery, and the other power output terminal is connected to the first battery through the first switch. The three switches are connected to the second battery; the input terminal of the boost circuit is connected to the second battery, and the output terminal is connected to the power supply pin through the second switch; the application processor according to the level state of the detection pin The type of the external device is detected, and the on-off status of the three switches is controlled according to the type of the external device. The utility model can effectively solve the problem of insufficient power supply capacity when the traditional single battery power supply design of the portable electronic product is externally connected to an OTG device.

Description

Power supply circuit and electronic products of portable electronic products with OTG function

technical field

The utility model belongs to the technical field of portable electronic products, and in particular relates to a circuit design of a power supply circuit applied in portable electronic products.

Background technique

With the rapid development of portable electronic technology, there are more and more types of portable electronic products, such as mobile phones, tablet computers, MP3, digital cameras, VR products (virtual reality products), AR products (augmented reality products), etc. These electronic products currently generally use USB ports as charging and data transmission interfaces, support hot-swappable functions, have a data transmission rate of up to 480Mbps or more, and have the characteristics of stable data transmission. However, the USB standard is a set of general interface standards developed around PCs. It does not support non-PC point-to-point connections. It cannot communicate directly between any two peripherals or between two hosts. It only supports between the master device and the slave device. data access functionality. And OTG (the English abbreviation of On-The-Go) technology can be used in the connection between various different equipments, realize the data exchange between different equipments. Therefore, the OTG device can act as a master device or operate as a slave device, so that two OTG devices can be directly connected without a PC and realize point-to-point communication. Therefore, OTG technology has been applied in some current portable electronic products.

Existing portable electronic products usually adopt a circuit design powered by a single battery, that is, a battery is used to supply power to the entire system circuit of the electronic product. However, due to different functional positioning of OTG equipment, its operating current is generally around several hundred milliamperes. When a portable electronic product is connected to an OTG device, a 5V power supply needs to be provided to the external device. However, some portable electronic products consume relatively large power consumption during operation. For example, the battery in a VR/AR all-in-one machine needs to supply power to multiple loads such as its internal application processor, radio frequency module, codec module, and display screen. It often happens that some portable electronic products cannot provide enough current to the external OTG device, resulting in the failure of the external OTG device to work normally, especially when the battery power is low, and even cause the portable electronic product to fail due to excessive power consumption. It is too large to shut down, and at the same time, it causes problems such as excessive heat generation of the whole machine, which seriously affects the user experience.

Contents of the invention

The utility model proposes a brand-new power supply circuit design for portable electronic products with OTG functions, which effectively solves the problem of insufficient power supply capacity when the portable electronic products work with external OTG devices.

In order to solve the above-mentioned technical problems, the utility model adopts the following technical solutions to achieve:

On the one hand, the utility model proposes a power supply circuit of a portable electronic product with an OTG function, including an interface, a first battery, a second battery, a charging chip, a boost circuit and an application processor; the interface is used for connecting an OTG The device or charger includes a power pin and a detection pin; the charging chip includes a power input terminal and two power output terminals, the power input terminal is connected to the power pin of the interface through a first switch, and the One of the two power supply output terminals is connected to the first battery, and the other is connected to the second battery through the third switch; the input terminal of the boost circuit is connected to the second battery, and the output terminal is connected to the power supply of the interface through the second switch pin; the application processor detects the type of the external device according to the level state of the detection pin of the interface, and if the interface is connected to an external charger, the application processor controls the first switch and the third The switch is closed, the second switch is opened, and the operation of the charging chip is controlled to charge the first battery and the second battery; if the interface is externally connected to an OTG device, the application processor controls the first switch and the second battery. The third switch is turned off, the second switch is closed, and controls the operation of the boost circuit to boost the output voltage of the second battery to the power supply voltage required by the OTG device, and supply power to the external OTG device through the interface.

Preferably, the first switch is preferably a normally closed switch, and the second switch and the third switch are preferably normally open switches.

In order that the portable electronic product of the present utility model can be externally connected with most of the current digital devices, the interface preferably adopts a USB interface, and the detection pin can be selected from a differential data pin of the USB interface to connect to the application processor, Realize the detection of the external device type.

Further, a boost chip is included in the boost circuit, and the enable terminal of the boost chip and the control terminal of the second switch are connected to the same control signal output pin of the application processor to control the boost chip The enabled state of the second switch and the closed state of the second switch are synchronously controlled, which reduces the occupation of pin resources of the application processor and facilitates the overall design of the system circuit.

In order to ensure the service life of the first battery and the second battery, the capacity of the first battery is preferably greater than the capacity of the second battery, and the charging chip is in the process of charging the first battery and the second battery. Preferably, the charging current output by the charging chip to the first battery is greater than the charging current output to the second battery.

In order to extend the battery life of the portable electronic product, a battery power detection module is also provided in the power supply circuit, connected to the first battery, and sends the detected battery power to the application processor; the application processor When it is detected that the remaining power of the first battery is lower than the set value and there is no external charger and OTG device on the interface, the third switch is controlled to be closed and the charging chip is controlled to short-circuit the two power output terminals , using the first battery and the second battery to supply power to the system circuit of the portable electronic product.

In order to meet the power demand of the application processor, a power management circuit is also provided in the power supply circuit, connected to the first battery, and converting the output voltage of the first battery into the working voltage required by the application processor, Power the application processor.

On the other hand, the utility model also proposes an electronic product, including a power supply circuit and an electric load, and the power supply circuit includes an interface, a first battery, a second battery, a charging chip, a boost circuit and an application processor; The interface is used for external OTG equipment or charger, including power supply pins and detection pins; the charging chip includes a power input terminal and two power output terminals, and the power input terminal is connected to the interface through the first switch A power supply pin, one of the two power supply output terminals is connected to the first battery, and the other is connected to the second battery through the third switch; the input terminal of the boost circuit is connected to the second battery, and the output terminal is connected to the second battery through the second switch Connect the power supply pin of the interface; the application processor detects the type of the external device according to the level state of the detection pin of the interface, if the interface is connected with an external charger, the application processor controls the The first switch and the third switch are closed, the second switch is opened, and the operation of the charging chip is controlled to charge the first battery and the second battery; if the interface is externally connected to an OTG device, the application processor controls The first switch and the third switch are disconnected, the second switch is closed, and the operation of the boost circuit is controlled to boost the output voltage of the second battery to the power supply voltage required by the OTG device, and the external OTG device power supply.

Compared with the prior art, the advantages and positive effects of the utility model are: the utility model sets two batteries in the portable electronic product, and specially designs the charge and discharge circuit for the two batteries, and utilizes one of the batteries as the electronic product. The power supply of the system circuit uses another battery to power the external OTG device, and makes the system power supply and OTG power supply independent of each other, thus effectively solving the problem of insufficient power supply capacity of the traditional single-battery power supply design of portable electronic products when the product is connected to an OTG device .

After reading the detailed description of the embodiments of the utility model in conjunction with the accompanying drawings, other features and advantages of the utility model will become clearer.

Description of drawings

Fig. 1 is a functional block diagram of a single battery power supply circuit of an existing portable electronic product;

Fig. 2 is a circuit schematic diagram of an embodiment of the power supply circuit proposed by the utility model.

Detailed ways

Below in conjunction with accompanying drawing, the specific embodiment of the present utility model is described in further detail.

Existing portable electronic products generally adopt a single battery design power supply circuit, such as the VR/AR all-in-one machine shown in Figure 1, including USB interface, charging chip, battery BAT, power management circuit and other main components. Among them, the USB interface is used as the charging and data interface of the VR/AR all-in-one machine, and is used for external chargers, USB devices or OTG devices. When an external charger is connected to the USB interface, the charging chip transmits the charging current output by the charger to the battery BAT to control the charging of the battery BAT. In the case of no charging current access, the working power required by each load in the system circuit is provided by the battery BAT. When an external OTG device is connected to the USB interface, the battery BAT needs to supply power for the system circuit and the external OTG device at the same time. The overcurrent protection of the system will cause the system to shut down and affect the normal use of the user.

In order to solve the above problems, the present embodiment adopts dual batteries to design the power supply circuit of portable electronic products, as shown in Figure 2, including interface, charging chip, first battery BAT1, second battery BAT2, boost circuit, first switch S1, Main components such as the second switch S2, the third switch S3, the power management circuit, and the application processor. Wherein, the interface is used for external chargers and OTG devices, and at least includes power pins for transmitting charging power or OTG power and detection pins for detecting types of external devices. As a preferred design of this embodiment, in order to improve the compatibility of the interface and meet the external requirements of more types of equipment, this embodiment preferably uses a USB connector as the interface, which can be connected to external chargers, OTG equipment, and PCs, etc. , to reduce the number of layouts of peripheral interfaces on portable electronic products, and simplify the structural design of electronic products. When a USB connector is selected as the interface, the differential data pins D+/D- of the USB interface can be used as detection pins to detect the type of the external device. Specifically, the differential data pin D+/D- of the USB interface can be connected to the application processor, and when the application processor detects that the two differential data pins D+ and D- are short-circuited, it determines that the external device is a charger; When the application processor detects that the two differential data pins D+ and D- are disconnected, it can accurately identify the specific type of the external device through data communication with the external device according to the preset communication protocol, for example OTG equipment or PC, etc. Of course, the application processor can also detect the type of the external device by using other existing identification means according to the level state of the differential data pin D+/D-, and this embodiment is not limited to the above examples.

Connect the power supply pin VBUS of the USB interface to the power supply input terminal of the charging chip through the first switch S1 connected in series. The battery BAT1, and another power supply output terminal OUT2 is connected to the second battery BAT2 through the third switch S3 connected in series with it. The second battery BAT2 is connected to the input terminal of the boost circuit, and the output terminal of the boost circuit is connected to the power supply pin VBUS of the USB interface through the second switch S2 connected in series.

In order to realize the automatic switching of the power supply lines, the three switches S1, S2, S3 are all selected electric control switches, such as triodes, MOS tubes, switch chips and the like. Connect the control ends of the three switches S1, S2, and S3 to the application processor, receive the control signal output by the application processor, and change its own on-off state according to the high or low level state of the control signal. In this embodiment, in consideration of the stability of power supply line switching, the first switch S1 is preferably a normally closed switch, and the second switch S2 and the third switch S3 are preferably normally open switches.

When the application processor detects that there is a charger or a PC connected to the USB interface, it keeps the normally closed state of the first switch S1 and the normally open state of the second switch S2, and controls the third switch S3 from the default disconnected state Switch to closed state. At the same time, the application processor outputs the enable signal EN1 to the enable terminal of the charging chip, controls the charging chip to enable operation, receives the charging current input by the charger through the power pin VBUS of the USB interface, and supplies power for the first battery BAT1 and the second battery. BAT2 charging energy storage. During the charging process, the power supply required by the system circuit is provided by the output of the charging chip to effectively control the heat generation of electronic products.

In this embodiment, the first battery BAT1 is used to supply power to the system circuit in the portable electronic product, and the second battery BAT2 is used to supply power to the external OTG device. Considering that the power consumption of the system circuit and the OTG device are different, when selecting the first battery BAT1 and the second battery BAT2, batteries with different capacities should be selected according to the actual power consumption of the system circuit and the OTG device. For example, for a VR/AR all-in-one machine, since the operating current of the system circuit of the all-in-one machine is greater than that of the OTG device, the power consumption of the system circuit is generally greater than the power consumption of the external OTG device. For the capacity of the second battery BAT2, it is necessary to ensure that the discharge time of the first battery BAT1 is greater than the discharge time of the second battery BAT2, that is, the capacity of the first battery BAT1 is selected to be greater than the capacity of the second battery BAT2, and the two batteries are reasonably configured The charging current of BAT1 and BAT2 is used to ensure the service life of the two batteries BAT1 and BAT2. In this embodiment, the operating parameters of the charging chip can be configured so that the charging current output from its power output terminal OUT1 to the first battery BAT1 is greater than the charging current output to the second battery BAT2 through its power output terminal OUT2.

When the application processor detects that an OTG device is connected to the USB interface, the first switch S1 is controlled to be turned off, the second switch S2 is turned on, and the third switch S3 is kept in a normally open state. At the same time, the application processor controls the boost circuit to start operation, and after the battery voltage of the second battery BAT2 is boosted and converted, the working power required by the OTG device is generated, such as +5V DC power, which is transmitted to the USB through the second switch S2 The power pin VBUS of the interface supplies power for the external OTG device. At this time, the system circuit of the portable electronic product is powered by the first battery BAT1. Since the power supply of the system circuit and the power supply of the OTG device do not affect each other, it can well meet the demand for simultaneous power consumption of the electronic product and the external OTG device. The power supply capability of portable electronic products.

In order to save the interface resources of the application processor, it is preferable to use one GPIO port GPIO2 of the application processor to output an effective enable signal EN2 (such as high level), and transmit it to the enable terminal of the boost circuit and the control of the second switch S2 respectively At the end, while controlling the second switch S2 to switch from the default normally open state to the closed state, the boost circuit is controlled to enable operation to meet the power supply requirements of the external OTG device. And when there is no OTG device on the USB interface, the application processor sets the enable signal EN2 to an invalid state (such as low level), controls the second switch S2 to disconnect, and cuts off the power supply of the second battery BAT2 and the USB interface. access, and at the same time control the step-up circuit to stop running, so as to reduce the power consumption of the whole machine.

In this embodiment, the boost circuit is preferably designed with a boost chip and a simple peripheral circuit to boost the battery voltage of the second battery BAT2 to a stable 5V voltage to meet the power demand of the current OTG equipment.

In addition, in the power supply circuit of this embodiment, a power detection module may be further provided, connected to the first battery BAT1, for detecting the remaining power of the first battery BAT1, and sending the detection result to the application processor. When the application processor detects that no device is connected to the USB interface, if the power of the first battery BAT1 is too low, for example, the power of the first battery BAT1 is lower than a set value, then it can control the second battery BAT2 to assist the second battery. A battery BAT1 jointly supplies power to the system circuit, so as to prolong the battery life of the electronic product.

In order to achieve the above design purpose, in this embodiment, a switch S4 is bridged between the positive poles of the first battery BAT1 and the second battery BAT2. The switch S4 can be a built-in switch in the charging chip and is connected to the two power outputs of the charging chip. Between terminals OUT1 and OUT2, it can also be configured independently of the charging chip. For the case where the switch S4 is a built-in switch of the charging chip, the application processor can communicate with the charging chip by means of data communication, and after controlling the charging chip to enable operation, notify the charging chip to short-circuit its two power output terminals OUT1, OUT2, and control the third switch S3 to close, and then control the parallel connection of the first battery BAT1 and the second battery BAT2 to supply power to the system circuit of the electronic product together. Specifically, one of the GPIO ports GPIO1 of the application processor can be connected to the enable terminal of the charging chip, and the enabling signal EN1 can be transmitted to control the enabling state of the charging chip; at the same time, a set of data of the application processor can be The interface DO is connected to the charging chip through a data line, and through data interaction with the charging chip, it can control the short-circuit state of the output terminals OUT1 and OUT2 of the power supply.

For the case where the switch S4 is configured independently of the charging chip, another GPIO port of the application processor can be used to generate a switch control signal to specifically control the on-off state of the switch S4. When no OTG device is connected to the USB interface and the power of the first battery BAT1 is less than the set value, the application processor outputs two switch signals through its two GPIO ports to control the third switch S3 and the fourth switch S4 to close, so as to Control the parallel connection of two batteries BAT1 and BAT2 to jointly supply power for the system circuit.

The system power supply output by the first battery BAT1 (or the first battery BAT1 and the second battery BAT2) can first be transmitted to the power management circuit for voltage stabilization and conversion, so as to convert it into the working power required by different power loads in the system circuit. Power application processors and other loads.

By selecting the appropriate power for the first battery BAT1 and the second battery BAT2, and reasonably configuring the on-off timing of the first, second, and third switches S1, S2, and S3, the use efficiency of the batteries BAT1, BAT2 can be improved, and the battery life can be extended. The duration of use of the entire electronic product.

Of course, the above description is not a limitation of the present utility model, and the present utility model is not limited to the above-mentioned examples. Those of ordinary skill in the art may make changes, modifications, additions or replacements within the essential scope of the present utility model. It should also belong to the protection scope of the present utility model.

Claims (8)

1. a kind of power supply circuit of the portable electronic product with OTG function, is characterized in that, including：

Interface is used for external OTG equipment or charger, including power pins and detection pin；

Charging chip a comprising power input and two power output ends, the power input pass through first switch The power pins of the interface are connected, the first battery of one of connection in described two power output ends, another is logical Cross third switch the second battery of connection；

Booster circuit, input terminal connect second battery, and output end connects the power supply of the interface by second switch Pin；

Application processor detects the type of external equipment according to the level state of the detection pin of the interface, if described Interface external charger, then the application processor controls the first switch and third closes the switch, and second switch disconnects, and The charging chip operation is controlled, is charged to first battery and the second battery；If the external OTG equipment of interface, institute It states application processor and controls the first switch and third switch disconnection, second switch closure, and control the booster circuit fortune Row, supply voltage needed for the output voltage of the second battery is boosted to OTG equipment are external OTG equipment by the interface Power supply.

2. the power supply circuit of the portable electronic product according to claim 1 with OTG function, which is characterized in that institute Stating first switch is normally closed switch, and the second switch and third switch are normal open switch.

3. the power supply circuit of the portable electronic product according to claim 1 with OTG function, which is characterized in that institute Stating interface is USB interface, and the detection pin is the differential data pin of USB interface, connects the application processor.

4. the power supply circuit of the portable electronic product according to claim 1 with OTG function, which is characterized in that It include a boost chip in the booster circuit, the enable end of the boost chip and the control terminal of second switch are connected and applied The same of processor controls signal output pin all the way, with the closed state of enabled state and second switch to boost chip into Row synchronously control.

5. the power supply circuit of the portable electronic product according to claim 1 with OTG function, which is characterized in that institute The capacity for stating the first battery is greater than the capacity of the second battery, and the charging chip is to first battery and the progress of the second battery During charge control, exports to the charging current of the first battery and be greater than the charging current of output to the second battery.

6. the power supply circuit of the portable electronic product according to any one of claim 1 to 5 with OTG function, It is characterized in that, further includes battery capacity detection module, connect first battery, and the battery capacity that will test is sent to institute State application processor；The application processor is in the remaining capacity for detecting the first battery lower than nothing in setting value and the interface When external charger and OTG equipment, controls the third and close the switch and control the described two power supplys of the charging chip short circuit Output end is powered using the circuit system that the first battery and the second battery are portable electronic product jointly.

7. the power supply circuit of the portable electronic product according to any one of claim 1 to 5 with OTG function, It is characterized in that, further includes electric power management circuit, connect first battery, the output voltage of the first battery is converted into described answer The operating voltage needed for processor is powered for the application processor.

8. a kind of electronic product, including power supply circuit and power load, which is characterized in that the power supply circuit is such as claim The power supply circuit of portable electronic product described in any one of 1 to 7 with OTG function.