阅读说明：本技术 一种usb复用电路 (USB multiplexing circuit ) 是由 林钊文 于 2020-04-21 设计创作，主要内容包括：本发明涉及USB通信技术领域,具体涉及一种USB复用电路,包括：处理器、USB切换开关、负载开关、USB集线器、Micro USB接口,处理器分别与USB切换开关、负载开关连接,USB切换开关分别与USB集线器、Micro USB接口连接,Micro USB接口分别与USB集线器、负载开关连接；当处理器触发高电平信号时连通所述处理器和Micro USB接口,当处理器触发低电平信号时连通所述处理器和USB集线器,本发明提供的USB复用电路能做到安卓设备内部的USB功能和外部的OTG功能复用。(The invention relates to the technical field of USB communication, in particular to a USB multiplexing circuit, which comprises: the processor is respectively connected with the USB transfer switch and the load switch, the USB transfer switch is respectively connected with the USB hub and the Micro USB interface, and the Micro USB interface is respectively connected with the USB hub and the load switch; the USB multiplexing circuit provided by the invention can multiplex the USB function inside the android device and the external OTG function.)

1. A USB multiplexing circuit, comprising: the USB hub and the Micro USB interface are connected with the processor, the USB switch is connected with the USB hub and the Micro USB interface, and the load switch is connected between the Micro USB interface and the processor;

the USB selector switch is used for responding to a high level signal triggered by the processor to be communicated with the processor and the Micro USB interface or responding to a low level signal triggered by the processor to be communicated with the processor and the USB hub, when the USB mode of the processor is set to be a slave mode, the processor triggers the high level signal, and when the USB mode of the processor is set to be a host mode, the processor triggers the low level signal;

the load switch is used for switching on a power supply when the Micro USB interface is connected to an external device;

the USB hub is used for expanding the USB interface of the processor from one to a plurality.

2. The USB multiplexing circuit according to claim 1, wherein a first resistor, a second resistor, and a diode are further disposed between the processor and the load switch, one end of the second resistor is connected to the processor, the other end of the second resistor is connected to the anodes of the first resistor and the diode, respectively, the other end of the first resistor is connected to a low-level voltage, the resistance of the first resistor is 1k Ω, and the resistance of the second resistor is 100 Ω.

3. The USB multiplexing circuit of claim 2, wherein the USB switch is a USB switch of model BCT4227, the USB switch comprises a first switch and a second switch, the first switch comprises a first OE enable port, a first S select port, a first D port, a first HSD1 port and a first HSD2 port, and the second switch comprises a second OE enable port, a second S select port, a second D port, a second HSD1 port and a second HSD2 port; the first S selection port and the second OE enabling port are connected to the ground in common, and the first OE enabling port and the second OE enabling port are connected with the anodes of the diodes respectively.

4. The USB multiplexing circuit of claim 2 wherein the load switch is of the type DIO7527B, and the load switch includes a low-level enable port, and the low-level enable port is connected to the cathode of the diode.

5. The USB multiplexing circuit of claim 2, wherein the Micro USB interface comprises a USB _ ID port, and the USB _ ID port is connected to a cathode of the diode.

6. The USB multiplexing circuit of claim 3 wherein the processor comprises a USB port, a GPIO port, and an OTG _ ID port, the USB port is connected to the second D port, the GPIO port is connected to the second resistor, and the OTG _ ID port is connected to the cathode of the diode.

7. A USB multiplexing circuit according to claim 3 wherein the USB hub comprises; the USB interface comprises an OTG interface, a first USB interface, a second USB interface, a third USB interface and a fourth USB interface, wherein the OTG interface is connected with a second HSD2 port, and the first USB interface is connected with a first HSD2 port.

Technical Field

The invention relates to the technical field of USB communication, in particular to a USB multiplexing circuit.

Background

The processor of the conventional android device generally provides only one USB interface, but in practical application, as the number of peripheral devices required to be connected by an electronic product increases, the android device often needs to be connected with a plurality of devices, and under the condition that the USB interface of the android device is connected with an internal element, the USB function in the android device can meet the requirement; when a peripheral is connected with the android device through the MicroUSB interface, namely the USB mode of the android device is set to be the USB OTG mode for use; or when a peripheral is connected with the android device through a USB interface, namely the USB mode of the android device is set to be the MASTER mode; the existing android equipment can not meet the requirements.

Therefore, it is desirable to provide a USB multiplexing circuit, which can satisfy multiplexing of the USB function inside the android device and the OTG function outside the android device.

Disclosure of Invention

The present invention is directed to a USB multiplexing circuit, which solves one or more of the problems of the prior art and provides at least one of the advantages of the USB multiplexing circuit.

In order to achieve the purpose, the invention provides the following technical scheme:

a USB multiplexing circuit, comprising: the USB hub and the Micro USB interface are connected with the processor respectively, and the load switch is connected between the Micro USB interface and the processor;

the USB selector switch is used for responding to a high level signal triggered by the processor to be communicated with the processor and the MicroUSB interface or responding to a low level signal triggered by the processor to be communicated with the processor and the USB hub, when the USB mode of the processor is set to be a slave mode, the processor triggers the high level signal, and when the USB mode of the processor is set to be a host mode, the processor triggers the low level signal;

the load switch is used for switching on a power supply when the Micro USB interface is connected to an external device;

the USB hub is used for expanding the USB interface of the processor from one to a plurality.

As a further improvement of the above technical solution, a first resistor, a second resistor, and a diode are further disposed between the processor and the load switch, one end of the second resistor is connected to the processor, the other end of the second resistor is respectively connected to the anodes of the first resistor and the diode, the other end of the first resistor is connected to a low level voltage, a resistance value of the first resistor is 1k Ω, and a resistance value of the second resistor is 100 Ω.

As a further improvement of the above technical solution, the USB switch is a USB switch with model number BCT4227, the USB switch includes a first switch and a second switch, the first switch includes a first OE enable port, a first S select port, a first D port, a first HSD1 port and a first HSD2 port, and the second switch includes a second OE enable port, a second S select port, a second D port, a second HSD1 port and a second HSD2 port; the first S selection port and the second OE enabling port are connected to the ground in common, and the first OE enabling port and the second OE enabling port are connected with the anodes of the diodes respectively.

As a further improvement of the above technical solution, the load switch is of a model DIO7527B, and the load switch includes a low-level enable port, and the low-level enable port is connected to a negative electrode of the diode.

As a further improvement of the above technical solution, the Micro USB interface includes a USB _ ID port, and the USB _ ID port is connected to a negative electrode of the diode.

As a further improvement of the above technical solution, the processor includes a USB port, a GPIO port, and an OTG _ ID port, the USB port is connected to the second D port, the GPIO port is connected to the second resistor, and the OTG _ ID port is connected to the cathode of the diode.

As a further improvement of the above technical solution, the USB hub includes; the USB interface comprises an OTG interface, a first USB interface, a second USB interface, a third USB interface and a fourth USB interface, wherein the OTG interface is connected with a second HSD2 port, and the first USB interface is connected with a first HSD2 port.

The invention has the beneficial effects that: the invention provides a USB multiplexing circuit, comprising: the USB hub and the Micro USB interface are connected with the processor; the USB selector switch is used for responding to a high level signal triggered by the processor to be communicated with the processor and the Micro USB interface or responding to a low level signal triggered by the processor to be communicated with the processor and the USB hub, when the USB mode of the processor is set to be a slave mode, the processor triggers the high level signal, and when the USB mode of the processor is set to be a host mode, the processor triggers the low level signal; the load switch is used for establishing communication connection between the processor and a load when detecting that the Micro USB interface is connected to the load; the USB hub is used for expanding the USB interface of the processor from one to a plurality. The USB multiplexing circuit provided by the invention can multiplex the USB function in the android device and the external OTG function.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without inventive exercise.

Fig. 1 is a schematic circuit diagram of a USB multiplexing circuit according to an embodiment of the present invention.

Detailed Description

The conception, the specific structure and the technical effects of the present invention will be clearly and completely described in conjunction with the embodiments and the accompanying drawings to fully understand the objects, the schemes and the effects of the present invention. It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict.

In the description of the present invention, if words such as "a plurality" are described, the meaning is one or more, the meaning of a plurality is two or more, more than, less than, more than, etc. are understood as excluding the present number, and more than, less than, etc. are understood as including the present number.