CN216561767U

CN216561767U - USB OTG power supply switching system

Info

Publication number: CN216561767U
Application number: CN202120724682.6U
Authority: CN
Inventors: 林永够
Original assignee: Vanstone Electronic Beijing Co Ltd
Current assignee: Vanstone Electronic Beijing Co Ltd
Priority date: 2021-04-09
Filing date: 2021-04-09
Publication date: 2022-05-17
Anticipated expiration: 2031-04-09

Abstract

The utility model relates to the technical field of USB buses, and discloses a USB OTG power supply switching system which comprises electronic equipment, wherein the electronic equipment is provided with a USB socket J1 and a power switch U1; when the external power supply device supplies power to the electronic device, the USB socket J1 is connected with the external power supply device through a USB power line; when the electronic device supplies power to the external device, the USB socket J1 is connected to the external device through the OTG patch cord. According to the utility model, through the identification of the USB ID pin, the master control controls the input and output IO and selects the power supply of the VBUS, so that the equipment is charged or external USB equipment is supplied with power, and the USB socket J1 can serve as a Host function and is externally connected with the USB equipment; the power supply device can also be used for supplying power to the electronic equipment. The utility model has simple operation, and 1 USB port is used for simultaneously realizing the USB Host function and the charging function.

Description

USB OTG power supply switching system

Technical Field

The utility model relates to the technical field of USB buses, in particular to a USB OTG power supply switching system.

Background

The Universal Serial Bus (USB) is an emerging data communication mode that gradually replaces other interface standards, and as a high-speed Serial Bus, the USB Bus has an extremely high transmission speed that can meet the application environment requirements of high-speed data transmission, and the Bus also has the advantages of simple power supply (Bus power supply), convenient installation and configuration (supporting plug and play and hot plug), simple expansion ports (127 external devices can be expanded at most through a hub), diversified transmission modes (4 transmission modes), and good compatibility (downward compatibility after product upgrade). With The increasing computing power of mobile devices and The demand of practical applications, The USB implementer association (USB IF) developed The specification of USB OTG (On-The-Go). However, the USB OTG port of the existing electronic device (e.g., POS device) cannot supply power to both the electronic device itself and the external device through the USB OTG port. Therefore, it is desirable to provide a USB OTG power switching system capable of supplying power to the electronic device itself through the USB OTG port and supplying power to the peripheral.

SUMMERY OF THE UTILITY MODEL

The present invention provides a USB OTG power switching system, so as to solve the above problems of the prior art.

The utility model provides a USB OTG power supply switching system, which comprises electronic equipment, wherein the electronic equipment is provided with a USB socket J1 and a power switch U1; when the external power supply device supplies power to the electronic device, the USB socket J1 is connected with the external power supply device through a USB power line; when the electronic device supplies power to the external device, the USB socket J1 is connected to the external device through the OTG patch cord.

Further, the USB socket comprises a VBUS pin, a DN pin, a DP pin, an ID pin and a GND pin, wherein the VBUS pin is connected with an external signal terminal VCC _ HOST, the DN pin is connected with a POS device signal USB DN, the ID pin is connected with a signal ID, and the GND pin is grounded.

Further, the peripheral signal terminal VCC _ HOST is respectively connected with a voltage regulator D1, a resistor R4, a triode Q2, a resistor R6, a capacitor C1 and a MOS transistor Q3, wherein one end of the voltage regulator D1, one end of the resistor R4, an E pole of the triode Q2, one end of the resistor R6, one end of the capacitor C1 and an S pole of the MOS transistor Q3 are respectively connected with the peripheral signal terminal VCC _ HOST; the other end of a voltage stabilizing tube D1 is connected with one end of a resistor R1, the other end of a resistor R1 is connected with a resistor R2, a resistor R3 and a triode Q1 respectively, the other end of the resistor R1 is connected with one end of a resistor R2, the other end of the resistor R2 is connected with a power supply signal HOST _ CT, one end of a resistor R3 is connected with the other end of a resistor R1, the other end of the resistor R3 is grounded, the B pole of the triode Q1 is connected with the other end of the resistor R1, the E pole of the triode Q1 is grounded, the C pole of the triode Q1 is connected with one end of a resistor R4 and one end of a resistor R5 respectively, the other end of a resistor R4 is connected with an external signal terminal VCC _ HOST, the other end of the resistor R5 is connected with the B pole of the triode Q2, the C pole of the triode Q2, the other end of the resistor R6, the other end of the capacitor C1 and the G pole of the MOS tube Q3 are connected with one end of the resistor R7 and the other end of the resistor R7 is grounded; MOS pipe Q3's E utmost point is connected with system internal voltage end VCC and electric capacity C2 respectively, and electric capacity C2's one end is connected with system internal voltage end VCC and MOS pipe Q3's E utmost point respectively, and electric capacity C2's the other end ground connection.

Further, the power switch U1 includes a signal input pin VIN, a signal output pin VOUT, an enable terminal EN, an external current-limiting control pin ILIM, and a ground pin GND, where the signal input pin VIN is connected to one end of the capacitor C3 and a system internal voltage terminal VCC, one end of the capacitor C3 is connected to the system internal voltage terminal VCC, and the other end of the capacitor C3 is grounded; the enabling end EN is connected with a system enabling USB _ HOST _ EN, a grounding pin GND is grounded, one end of a signal output pin VOUT is respectively connected with a diode D2, a power supply signal HOST _ CT and a capacitor C4, the power supply signal HOST _ CT is respectively connected with one end of a diode D2 and one end of a capacitor C4, one end of a capacitor C4 is connected with one end of a diode D2, the other end of the diode D2 is connected with a peripheral signal end VCC _ HOST, the other end of the capacitor C4 is grounded, an external current limiting control pin ILIM is connected with one end of a resistor R8, and the other end of the resistor R8 is grounded.

Further, when the external power supply device supplies power to the electronic device, the USB socket J1 is connected to the external power supply device through a USB power line, the external power supply device provides a preset voltage signal to the electronic device, the preset voltage signal is input to the POS device as the peripheral signal terminal VCC _ HOST, the system enable USB _ HOST _ EN is at a low level, the power switch U1 is not turned on, the power signal HOST _ CT is at a low level, the voltage regulator tube D1, the resistor R1, the resistor R2, the resistor R3, the triode Q1, the resistor R4, the resistor R5, the triode Q2, the resistor R6, the capacitor C1, the resistor R7, and the MOS tube Q3 form a loop, so that the G of the MOS tube Q3 is at a low level, the MOS tube Q3 is turned on, and the peripheral signal terminal VCC _ HOST supplies power to the system internal voltage terminal VCC.

Further, when the electronic device supplies power to the external device, the USB socket J1 is connected to the external device through an OTG patch cord, the ID pin of the USB socket J1 is pulled down to a low level by the external device ground according to the USB OTG specification, the signal ID is a low level, the system enable USB _ HOST _ EN is a high level, the enable terminal EN of the power switch U1 is a high level, the power switch U1 is turned on, the system internal voltage terminal VCC is communicated with the power signal HOST _ CT, the power signal HOST _ CT is communicated with the peripheral signal terminal VCC _ HOST through the diode D2, the power signal HOST _ CT is a high level, the B terminal of the transistor Q1 is a high level, the transistor Q1 is conductive, the B terminal of the transistor Q2 is pulled down to a low level, the transistor Q2 is conductive, the G terminal of the transistor Q2 is in accordance with the voltage of the S terminal of the transistor Q2, the transistor Q2 is nonconductive, the system internal voltage terminal is communicated with the peripheral signal terminal VCC _ HOST, the electronic device supplies power to the external device.

Further, the electronic device comprises a mobile terminal, and the mobile terminal comprises a POS device.

The utility model has the beneficial effects that: the USB OTG power supply switching system designed by the utility model identifies through the USB ID pin, the master control controls the input and output IO, and selects the VBUS power supply, thereby charging the equipment or supplying power to external USB equipment; the power supply device can also be used for supplying power to the electronic equipment. The utility model has simple operation, and 1 USB port is used for simultaneously realizing the USB Host function and the charging function.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments are briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

Fig. 1 is a pin diagram of a USB socket J1 according to a first embodiment of the present invention.

Fig. 2 is a schematic diagram of a circuit connection between the peripheral signal terminal VCC _ HOST and the system internal voltage terminal VCC according to the first embodiment.

Fig. 3 is a pin diagram of a power switch U1 according to a first embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the utility model, are given by way of illustration only. It is noted that the terms "comprises" and "comprising," and any variations thereof, in the description and claims of the present invention and the above-described drawings are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of elements is not necessarily limited to those elements, but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

The first embodiment, a USB OTG power supply switching system includes an electronic device, where the electronic device is provided with a USB socket J1 and a power switch U1; when the external power supply device supplies power to the electronic device, the USB socket J1 is connected with the external power supply device through a USB power line; when the electronic device supplies power to the external device, the USB socket J1 is connected to the external device through the OTG patch cord. In this embodiment, the electronic device is a POS device.

As shown in fig. 1, the USB socket J1 includes a VBUS pin, a DN pin, a DP pin, an ID pin, and a GND pin, the VBUS pin is connected to the peripheral signal terminal VCC _ HOST, the DN pin is connected to the POS device signal USB DN, the ID pin is connected to the signal ID, and the GND pin is grounded.

As shown in fig. 2, the peripheral signal terminal VCC _ HOST is connected to a voltage regulator D1, a resistor R4, a transistor Q2, a resistor R6, a capacitor C1, and a MOS transistor Q3, respectively, and one end of the voltage regulator D1, one end of the resistor R4, an E-pole of the transistor Q2, one end of the resistor R6, one end of the capacitor C1, and an S-pole of the MOS transistor Q3 are connected to the peripheral signal terminal VCC _ HOST; the other end of the voltage-stabilizing tube D1 is connected with one end of a resistor R1, the other end of the resistor R1 is connected with a resistor R2, a resistor R3 and a triode Q1 respectively, the other end of the resistor R1 is connected with one end of a resistor R2, the other end of the resistor R2 is connected with a power supply signal HOST _ CT, and the HOST _ CT is a power supply signal and is a power supply obtained after a system internal voltage end VCC is controlled by a power supply switch U1. One end of a resistor R3 is connected with the other end of a resistor R1, the other end of the resistor R3 is grounded, the B pole of a triode Q1 is connected with the other end of a resistor R1, the E pole of a triode Q1 is grounded, the C pole of the triode Q1 is connected with one end of a resistor R4 and one end of a resistor R5 respectively, the other end of the resistor R4 is connected with an external signal terminal VCC _ HOST, the other end of the resistor R5 is connected with the B pole of a triode Q2, the C pole of the triode Q2, the other end of the resistor R6, the other end of a capacitor C1 and the G pole of a MOS transistor Q3 are connected with one end of a resistor R7 respectively, and the other end of the resistor R7 is grounded; an E pole of the MOS transistor Q3 is connected with a system internal voltage end VCC and a capacitor C2 respectively, one end of a capacitor C2 is connected with the system internal voltage end VCC and the E pole of the MOS transistor Q3 respectively, and the other end of the capacitor C2 is grounded.

As shown in fig. 3, the power switch U1 includes a signal input pin VIN, a signal output pin VOUT, an enable terminal EN, an external current-limiting control pin ILIM, and a ground pin GND, where the signal input pin VIN is connected to one end of a capacitor C3 and a system internal voltage terminal VCC, one end of a capacitor C3 is connected to the system internal voltage terminal VCC, and the other end of the capacitor C3 is grounded; the enabling end EN is connected with a system enabling USB _ HOST _ EN, the grounding pin GND is grounded, one end of the signal output pin VOUT is respectively connected with a diode D2, a power supply signal HOST _ CT and a capacitor C4, the power supply signal HOST _ CT is respectively connected with one end of a diode D2 and one end of a capacitor C4, one end of a capacitor C4 is connected with one end of a diode D2, the other end of the diode D2 is connected with a peripheral signal end VCC _ HOST, the other end of the capacitor C4 is grounded, an external current limiting control pin ILIM is connected with one end of a resistor R8, and the other end of the resistor R8 is grounded.

When the external power supply device supplies power to the electronic device, the USB socket J1 is connected with the external power supply device through a USB power line, the external power supply device provides a preset voltage signal to the electronic device, the preset voltage signal is input to the POS device as the peripheral signal terminal VCC _ HOST, the system enable USB _ HOST _ EN is at a low level, the power switch U1 is not turned on, the power signal HOST _ CT is at a low level, the regulator tube D1, the resistor R1, the resistor R2, the resistor R3, the triode Q1, the resistor R4, the resistor R5, the triode Q2, the resistor R6, the capacitor C1, the resistor R7, and the MOS tube Q3 form a loop, so that the G of the MOS tube Q3 is at a low level, the MOS tube Q3 is turned on, the peripheral signal terminal VCC _ HOST supplies power to the system internal voltage terminal VCC, and the external power supply device supplies power to the electronic device. When the USB socket J1 is connected with an external USB power line, 5V/2A is provided for supplying power to the electronic equipment.

When the electronic equipment supplies power to the external equipment, the USB socket J1 is connected with the external equipment through the OTG patch cord, according to the USB OTG specification, an ID pin of a USB socket J1 is pulled down to a low level by an external device ground, a signal ID is a low level, a system enable USB _ HOST _ EN is a high level, an enable end EN of a power switch U1 is a high level, a power switch U1 is conducted, a system internal voltage end VCC is communicated with a power signal HOST _ CT, the power signal HOST _ CT is communicated with an external signal end VCC _ HOST through a diode D2, the power signal HOST _ CT is a high level, a B electrode of a triode Q1 is a high level, a triode Q1 is conducted, a B electrode of the triode Q2 is pulled down to a low level, a triode Q2 is conducted, a G electrode of the triode Q2 is consistent with a S electrode of a triode Q2 in voltage, the triode Q2 is not conducted, the system internal voltage end VCC is communicated with the external signal end VCC _ HOST, and the electronic device supplies power to the external device. When the USB socket J1 is connected with an external device through an OTG patch cord, the POS device needs to supply power to the external device.

By adopting the technical scheme disclosed by the utility model, the following beneficial effects are obtained:

the USB OTG power supply switching system designed by the utility model identifies through the USB ID pin, the master control controls the input and output IO, and selects the VBUS power supply, thereby charging the equipment or supplying power to external USB equipment; the power supply device can also be used for supplying power to the electronic equipment. The utility model has simple operation, and 1 USB port is used for simultaneously realizing the USB Host function and the charging function.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that it will be apparent to those skilled in the art that various modifications and improvements can be made without departing from the principle of the present invention, and such modifications and improvements should also be considered within the scope of the present invention.

Claims

1. The USB OTG power supply switching system is characterized by comprising electronic equipment, wherein the electronic equipment is provided with a USB socket J1 and a power switch U1; when the external power supply device supplies power to the electronic device, the USB socket J1 is connected with the external power supply device through a USB power line; when the electronic device supplies power to the external device, the USB socket J1 is connected to the external device through the OTG patch cord.

2. The USB OTG power supply switching system of claim 1, wherein the USB socket comprises a VBUS pin, a DN pin, a DP pin, an ID pin and a GND pin, the VBUS pin is connected with a peripheral signal terminal VCC _ HOST, the DN pin is connected with a POS device signal USB DN, the ID pin is connected with a signal ID, and the GND pin is grounded.

3. The USB OTG power supply switching system according to claim 2, wherein a voltage regulator D1, a resistor R4, a transistor Q2, a resistor R6, a capacitor C1 and a MOS transistor Q3 are respectively connected to the peripheral signal terminal VCC _ HOST, and one end of the voltage regulator D1, one end of the resistor R4, an E pole of the transistor Q2, one end of the resistor R6, one end of the capacitor C1 and an S pole of the MOS transistor Q3 are respectively connected to the peripheral signal terminal VCC _ HOST; the other end of the voltage-stabilizing tube D1 is connected with one end of a resistor R1, the other end of the resistor R1 is respectively connected with a resistor R2, a resistor R3 and a triode Q1, the other end of the resistor R1 is connected with one end of the resistor R2, the other end of the resistor R2 is connected with a power supply signal HOST _ CT, one end of the resistor R3 is connected with the other end of the resistor R1, the other end of the resistor R3 is grounded, the B pole of the triode Q1 is connected with the other end of the resistor R1, the E pole of the triode Q1 is grounded, the C pole of the triode Q1 is respectively connected with one end of a resistor R4 and one end of a resistor R5, the other end of the resistor R4 is connected with the peripheral signal terminal VCC _ HOST, the other end of the resistor R5 is connected with the B pole of the triode Q2, the C pole of the triode Q2, the other end of the resistor R6, the other end of the capacitor C1 and one end of the G pole of the MOS tube Q3 are respectively connected with resistors R7, the other end of the resistor R7 is grounded; MOS pipe Q3's E utmost point is connected system internal voltage end VCC and electric capacity C2 respectively, electric capacity C2's one end respectively with system internal voltage end VCC with MOS pipe Q3's E utmost point is connected, electric capacity C2's other end ground connection.

4. The USB OTG power supply switching system according to claim 3, wherein the power switch U1 comprises a signal input pin VIN, a signal output pin VOUT, an enable terminal EN, an external current limiting control pin ILIM and a ground pin GND, the signal input pin VIN is connected with one end of a capacitor C3 and a system internal voltage terminal VCC, one end of a capacitor C3 is connected with the system internal voltage terminal VCC, and the other end of the capacitor C3 is grounded; the enabling end EN is connected with a system enabling USB _ HOST _ EN, the grounding pin GND is grounded, one end of the signal output pin VOUT is connected with a diode D2, a power supply signal HOST _ CT and a capacitor C4 respectively, the power supply signal HOST _ CT is connected with one end of a diode D2 and one end of a capacitor C4 respectively, one end of a capacitor C4 is connected with one end of a diode D2, the other end of the diode D2 is connected with an external signal end VCC _ HOST, the other end of the capacitor C4 is grounded, the external current limiting control pin ILIM is connected with one end of a resistor R8, and the other end of the resistor R8 is grounded.

5. The USB OTG power supply switching system according to claim 4, wherein the external power supply device provides a preset voltage signal to the electronic device, the preset voltage signal is input to the POS device as a peripheral signal terminal VCC _ HOST, the system enable USB _ HOST _ EN is at a low level, the power switch U1 is not turned on, the power signal HOST _ CT is at a low level, and the voltage regulator tube D1, the resistor R1, the resistor R2, the resistor R3, the transistor Q1, the resistor R4, the resistor R5, the transistor Q2, the resistor R6, the capacitor C1, the resistor R7 and the MOS tube Q3 form a loop, so that the G electrode of the MOS tube Q3 is at a low level, the MOS tube Q3 is turned on, and the peripheral signal terminal VCC _ HOST supplies power to the system internal voltage terminal VCC.

6. The USB OTG power switching system of claim 5, according to the USB OTG specification the ID pin of the USB socket J1 is pulled down to low level by the external equipment ground, the signal ID is low level, system enable USB _ HOST _ EN is high level, enable end EN of power switch U1 is high level, power switch U1 is conducted, system internal voltage end VCC is communicated with power signal HOST _ CT, power signal HOST _ CT is communicated with peripheral signal end VCC _ HOST through diode D2, power signal HOST _ CT is high level, pole B of triode Q1 is high level, triode Q1 is conducted, pole B of triode Q2 is pulled down to low level, triode Q2 is conducted, pole G of triode Q2 is consistent with pole S of triode Q2 in voltage, triode Q2 is not conducted, system internal voltage end VCC is communicated with peripheral signal end VCC _ HOST, the electronic equipment supplies power to the external equipment.

7. The USB OTG power switching system according to claim 1, wherein the electronic device comprises a mobile terminal, the mobile terminal comprising a POS device.