CN108572935B - USB interface control circuit - Google Patents
USB interface control circuit Download PDFInfo
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- CN108572935B CN108572935B CN201710130589.0A CN201710130589A CN108572935B CN 108572935 B CN108572935 B CN 108572935B CN 201710130589 A CN201710130589 A CN 201710130589A CN 108572935 B CN108572935 B CN 108572935B
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F13/00—Interconnection of, or transfer of information or other signals between, memories, input/output devices or central processing units
- G06F13/38—Information transfer, e.g. on bus
- G06F13/40—Bus structure
- G06F13/4063—Device-to-bus coupling
- G06F13/4068—Electrical coupling
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F2213/00—Indexing scheme relating to interconnection of, or transfer of information or other signals between, memories, input/output devices or central processing units
- G06F2213/0042—Universal serial bus [USB]
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Abstract
A USB interface control circuit comprises a USB connector, a power supply control module, a signal adjusting module, a main control module and a switch module. The USB connector is used for outputting a plugging signal when being connected with a USB device. The power supply control module is used for outputting a control signal when receiving the plugging signal. The signal conditioning module is used for carrying out signal strengthening processing on the signals received by the USB connector. The main control module is electrically connected with the power supply control module and the signal adjusting module. The switch module is used for outputting an enabling signal when receiving the control signal. The signal adjusting module is further used for normally working when receiving the enabling signal, and the main control module is further used for detecting the plugging state of the USB equipment through the signal adjusting module. The USB interface control circuit can ensure that the USB equipment is electrified and then is subjected to handshake communication when the USB equipment is accessed, and further can improve the stability of the handshake communication.
Description
Technical Field
The invention relates to the field of electronic equipment, in particular to a USB interface control circuit.
Background
With the development of mobile technology, the USB interface becomes an indispensable part of mobile devices. In the existing traditional USB interface, the USB Type-A and USB Type-B interfaces are increasingly difficult to meet the requirement that the transmission speed of new equipment is higher. A new generation of USB Type-C interface is produced. The USB Type-C interface meets the requirement that the transmission speed of the new equipment is higher.
In order to respond to the insertion of the external USB device at any time, the Type-C interface controller needs to monitor the level state of the detection pin of the Type-C connector in real time. When a USB device is accessed, the Type-C interface controller needs to communicate with the USB device according to the protocol of the USB Type-C. However, when the external USB device is not yet powered to communicate with it, communication will not be successful, so that communication failure occurs.
Disclosure of Invention
In view of the above, it is desirable to provide a USB interface control circuit that can improve communication stability in response to insertion of an external USB device.
An embodiment of the present invention provides a USB interface control circuit, which includes a USB connector, a power supply control module, a signal conditioning module, a main control module, and a switch module. The USB connector is used for outputting a plugging signal when being connected with a USB device. The power supply control module is electrically connected to the USB connector and is used for outputting a control signal when receiving the plugging signal. The signal adjusting module is electrically connected to the USB connector and is used for performing signal enhancement processing on the signals received by the USB connector. The main control module is electrically connected with the power supply control module and the signal adjusting module. The switch module is electrically connected to the power supply control module and the signal adjusting module and is used for outputting an enable signal when receiving the control signal. The signal adjusting module is further configured to normally operate when receiving the enabling signal, and the main control module is further configured to detect the plugging state of the USB device through the signal adjusting module.
Preferably, the power supply control module is further configured to output a power signal when receiving the plugging signal, where the power signal is used to supply power to the USB device.
Preferably, the power supply control module includes a first signal control pin and a second signal control pin, when the power supply control module receives the plugging signal, the first signal control pin and the second signal control pin are converted from a first level signal to a second level signal, the power supply control module is configured to output the power signal when the second signal control pin is the second level signal, the first signal control pin is configured to output the control signal, and the control signal is the second level signal.
Preferably, the first signal control pin is configured to convert the first level signal into the second level signal after the second signal control pin is converted into the second level signal.
Preferably, the enable signal is a high level signal, the first level signal is a low level signal, and the second level signal is a high level signal.
Preferably, the USB connector includes a first detection pin and a second detection pin; the first detection pin is used for outputting the plugging signal when detecting that the USB connector and the USB equipment are in a positive plugging state; the second detection pin is used for outputting the plugging signal when detecting that the USB connector and the USB equipment are in a reverse plugging state.
Preferably, the switch module includes:
the first switch tube comprises a control end, a first end and a second end, the control end is electrically connected to the power supply control module and used for receiving the control signal, and the second end is grounded;
one end of the first resistor is electrically connected to a first power supply, and the other end of the first resistor is electrically connected to the first end of the first switch tube; and
the second switch tube comprises a control end, a first end and a second end, the control end is electrically connected to the first end of the first switch tube, the first end is electrically connected to the signal conditioning module and used for outputting the enable signal, and the second end is grounded.
Preferably, the first switch tube and the second switch tube are both N-channel field effect transistors, the control end of the first switch tube and the control end of the second switch tube are gates of the N-channel field effect transistors, the first end of the first switch tube and the first end of the second switch tube are drains of the N-channel field effect transistors, and the second end of the first switch tube and the second end of the second switch tube are sources of the N-channel field effect transistors.
Preferably, the signal conditioning module is further configured to stop working when the enable signal is not received.
Preferably, the USB interface control circuit further includes a current detection module electrically connected to the power supply control module and the main control module, the current detection module is configured to detect a current magnitude of the power signal, and the main control module is further configured to determine whether overcurrent protection needs to be started according to the current magnitude of the power signal.
Compared with the prior art, the USB interface control circuit can ensure that the USB equipment is electrified and then is subjected to handshake communication with the USB equipment when the USB equipment is accessed, so that the situation that the USB equipment cannot be identified can be avoided, and the stability of handshake communication is improved.
Drawings
FIG. 1 is an operating environment diagram of a USB interface control circuit according to a preferred embodiment of the present invention.
FIG. 2 is a functional block diagram of a USB interface control circuit according to a preferred embodiment of the present invention.
FIG. 3 is a circuit diagram of a USB interface control circuit according to a preferred embodiment of the present invention.
Description of the main elements
The following detailed description will further illustrate the invention in conjunction with the above-described figures.
Detailed Description
Referring to fig. 1-2, a USB interface control circuit 100 is provided according to an embodiment of the present invention.
The USB interface control circuit 100 is electrically connected to the USB device 200. The USB device 200 may be a device supporting the USB3.0 specification, and the USB device 200 includes a first USB connector 1.
The USB interface control circuit 100 includes a second USB connector 10, a power supply control module 20, a signal conditioning module 30, a main control module 40, and a switch module 50. The first USB connector 1 and the second USB connector 10 may be Type-C connectors, and the first USB connector 1 and the second USB connector 10 may be inserted into each other to electrically connect the USB device 200 and the USB interface control circuit 100. When the first USB connector 1 is plugged with the second USB connector 10, the second USB connector 10 outputs a plugging signal. The power supply control module 20 is electrically connected to the second USB connector 10, and the power supply control module 20 is configured to output a control signal and a power signal when receiving the plugging signal output by the second USB connector 10.
The signal conditioning module 30 is electrically connected to the second USB connector 10, and the signal conditioning module 30 is configured to perform signal enhancement processing on the signal received by the second USB connector 10, so as to avoid transmission distortion of the signal and stabilize signal quality. The main control module 40 is electrically connected to the power supply control module 20 and the signal conditioning module 30.
The switch module 50 is electrically connected to the power supply control module 20 and the signal conditioning module 30, and the switch module 50 is configured to output an enable signal when receiving the control signal output by the power supply control module 20. The signal conditioning module 30 is further configured to operate normally when receiving the enable signal output by the switch module 50, and the main control module 40 is further configured to detect the plugging status of the USB device 200 through the signal conditioning module 30.
In an embodiment of the present invention, the power signal outputted by the power supply control module 20 is used to supply power to the USB device 200. When the signal conditioning module 30 works normally, the main control module 40 can detect the plugging status of the USB device 200 through the signal conditioning module 30 to identify the USB device 200. When the signal conditioning module 30 stops working, the main control module 40 cannot detect the plugging status of the USB device 200 through the signal conditioning module 30, and further cannot identify the USB device 200.
In an embodiment of the invention, the USB device 200 may be a USB disk. The USB interface control circuit 100 may be provided in a terminal device, which may be a notebook computer, a PC computer, a server, or the like.
In one embodiment of the present invention, the second USB connector 10 includes a first detection pin CC1 and a second detection pin CC 2. The first detection pin CC1 is used for outputting the plugging signal when detecting that the first USB connector 1 and the second USB connector are in a positive plugging state. The second detection pin CC2 is used for outputting the plugging signal when detecting that the first USB connector 1 and the second USB connector are in the anti-plugging state.
The power supply control module 20 includes a first signal control pin GPIO1 and a second signal control pin GPIO 2. When the power supply control module 20 receives the plugging signal output by the second USB connector 10, both the first signal control pin GPIO1 and the second signal control pin GPIO2 are converted from the first level signal to the second level signal. The power supply control module 20 is configured to output a power signal when the second signal control pin GPIO2 is a second level signal, and the first signal control pin GPIO1 is configured to output a control signal, which is the second level signal.
In an embodiment of the present invention, the first level signal is a low level signal, and the second level signal is a high level signal. The enable signal output by the switch module 50 is a high level signal. The power supply signal output by the power supply control module 20 is preferably a +5V voltage signal.
In an embodiment of the invention, the first signal control pin GPIO1 is configured to be converted into the second level signal from the first level signal after the second signal control pin GPIO2 is converted into the second level signal. That is, the time for the first signal control pin GPIO1 to convert from the first level signal to the second level signal is later than the time for the second signal control pin GPIO2 to convert from the first level signal to the second level signal, so that when the signal conditioning module 30 receives the control signal output by the first signal control pin GPIO1, the power signal output by the power supply control module 20 already supplies power to the USB device 200.
The main control module 40 is preferably a Platform Controller Hub (PCH) chip, and the main control module 40 may acquire the plugging status of the USB device 200 by communicating with the signal conditioning module 30, so as to identify and communicate with the USB device.
In an embodiment of the present invention, the USB interface control circuit 100 further includes a current detecting module 60 electrically connected to the power supply control module 20 and the main control module 40, the current detecting module 60 is configured to detect a current magnitude of a power signal output by the power supply control module 20, and the main control module 40 is further configured to determine whether to start the over-current protection according to the current magnitude of the power signal.
It should be noted that, when the first USB connector 1 is plugged into the second USB connector 10, because there is a certain delay in the electronic components, it may happen that the USB device 200 has not received the power signal output by the power supply control module 20 when the main control module 40 detects the USB device 200 through the signal conditioning module 30. That is, the power control module 20 does not output the power signal immediately after the plugging, and the USB device 200 is not powered immediately, which has a certain delay. If the main control module 40 communicates with the USB device 200 through the signal conditioning module 30, the main control module 40 cannot successfully communicate with the USB device 200 because the USB device 200 is not powered, which may result in that the USB device 200 cannot be normally identified. In an embodiment of the present invention, since the signal conditioning module 30 stops working when not receiving the enable signal output by the switch module 50, and the signal conditioning module 30 normally works when receiving the enable signal output by the switch module 50, when the signal conditioning module 30 is normal, the USB device 200 is already powered, so as to ensure that the main control module 40 and the USB device 200 can successfully communicate after being plugged.
Referring to fig. 3, in an embodiment of the invention, the power supply control module 20 includes a power controller chip U1, a power switch chip U2, a first capacitor C1, and a second capacitor C2. The power controller chip U1 includes a first power terminal VCC1, a first sensing terminal CC3, a second sensing terminal CC4, a first signal control pin GPIO1, a second signal control pin GPIO2, and a third signal control pin GPIO 3. The first power source terminal VCC1 is electrically connected to the first power source DC1, the first detection terminal CC3 is electrically connected to the first detection pin CC1, and the second detection terminal CC4 is electrically connected to the second detection pin CC 2. The power switch chip U2 includes an input terminal IN, an output terminal OUT, a control terminal EN, a ground terminal GND, and a current detection terminal FLG. The input terminal IN is electrically connected to the first power supply DC1, the control terminal EN is electrically connected to the second signal control pin GPIO2 of the power supply controller chip U1, and the ground terminal GND is grounded. One end of the first capacitor C1 is electrically connected to the input terminal IN, and the other end of the first capacitor C1 is grounded. One end of the second capacitor C2 is electrically connected to the output terminal OUT, and the other end of the second capacitor C2 is grounded. When the power switch chip U2 is turned on, the output voltage of the output terminal OUT equals to the voltage of the first power DC1, and the output voltage of the output terminal OUT can supply power to the USB device 200.
The main control module 40 includes a first signal pin SLP _ S, a second signal pin OC, a third signal pin TXP, a fourth signal pin TXN, a fifth signal pin PXP and a sixth signal pin PXN. The first signal pin SLP _ S is electrically connected to the third signal control pin GPIO3 of the power controller chip U1, and the second signal pin OC is electrically connected to the current detection terminal FLG.
The second USB connector 10 further includes first to fourth communication pins CC5, CC6, CC7, CC 8.
The signal conditioning module 30 includes a signal conditioning chip U3 and a first resistor R1. The signal conditioning chip U3 includes first to eighth pins P1-P8, an enable pin PD, and a second power terminal VCC 2. The first pin P1 is electrically connected to the third signal pin TXP, the second pin P2 is electrically connected to the fourth signal pin TXN, the third pin P3 is electrically connected to the fifth signal pin PXP, and the fourth pin P4 is electrically connected to the sixth signal pin PXN. The fifth through eighth pins P5-P8 are electrically connected to the first through fourth communication pins CC5-CC8, respectively. The enable pin PD is electrically connected to one end of a first resistor R1, and the other end of the first resistor R1 is electrically connected to the second power supply DC 2. The second power source terminal VCC2 is electrically connected to a second power source DC 2.
The switch module 50 includes a second resistor R2, a first switch Q1, and a second switch Q2. The first switch Q1 includes a control terminal, a first terminal and a second terminal. The control end of the first switch tube Q1 is electrically connected to the first signal control pin GPIO1, and is configured to receive a control signal. A first end of the first switch tube Q1 is electrically connected to one end of the second resistor R2, and a second end of the first switch tube Q1 is grounded. The other end of the second resistor R2 is electrically connected to the first power supply DC 1. The second switch tube Q2 includes a control terminal, a first terminal and a second terminal. The control end of the second switch tube Q2 is electrically connected to the first end of the first switch tube Q1, the first end of the second switch tube Q2 is electrically connected to the enable pin PD, and the second end of the second switch tube Q2 is grounded.
When the control terminal of the first switch transistor Q1 is at a high level, the first switch transistor Q1 is turned on, and the second switch transistor Q2 is turned off. At this time, the enable pin PD of the signal conditioning chip U3 is at a high level, the signal conditioning chip U3 works normally, and the main control module 40 can communicate with the USB device 200 through the signal conditioning chip U3. When the control terminal of the first switch transistor Q1 is at a low level, the first switch transistor Q1 is turned off, and the second switch transistor Q2 is turned on. At this time, the enable pin PD of the signal conditioning chip U3 is at low level, the signal conditioning chip U3 stops working, and the main control module 40 cannot communicate with the USB device 200 through the signal conditioning chip U3.
The current detection module 60 includes a third resistor R3 and a fourth resistor R4. One end of the third resistor R3 is electrically connected to the first power DC1, and the other end of the third resistor R3 is electrically connected to the current detection terminal FLG and the second signal pin OC. One end of the fourth resistor R4 is electrically connected to the other end of the third resistor R3, and the other end of the fourth resistor R4 is grounded.
In one embodiment of the present invention, the first power supply DC1 is preferably a +5V DC power supply, and the second power supply DC2 is preferably a +3.3V DC power supply.
In one embodiment of the present invention, the first switch Q1 and the second switch Q2 are preferably N-channel field effect transistors. The control end of the first switch transistor Q1 and the control end of the second switch transistor Q2 are gates of N-channel field effect transistors, the first end of the first switch transistor Q1 and the first end of the second switch transistor Q2 are drains of the N-channel field effect transistors, and the second end of the first switch transistor Q1 and the second end of the second switch transistor Q2 are sources of the N-channel field effect transistors.
The USB interface control circuit can ensure that the USB equipment is electrified and then is subjected to handshake communication when the USB equipment is accessed, thereby avoiding the situation that the USB equipment cannot be identified and improving the stability of handshake communication.
It will be apparent to those skilled in the art that other variations and modifications may be made in accordance with the invention and its spirit and scope in accordance with the practice of the invention disclosed herein.
Claims (9)
1. The utility model provides a USB interface control circuit, includes USB connector and power supply control module, the USB connector is used for exporting the grafting signal when being connected with a USB equipment, power supply control module electricity connect in the USB connector for export control signal and power signal when receiving the grafting signal, its characterized in that, power signal is used for to USB equipment supplies power, USB interface control circuit still includes:
the signal adjusting module is electrically connected to the USB connector and is used for performing signal strengthening processing on the signals received by the USB connector;
the main control module is electrically connected with the power supply control module and the signal regulating module; and
the switch module is electrically connected with the power supply control module and the signal regulating module and is used for outputting an enabling signal when receiving the control signal;
the signal adjusting module is further configured to normally operate when receiving the enabling signal, and the main control module is further configured to detect the plugging state of the USB device through the signal adjusting module.
2. The USB interface control circuit according to claim 1, wherein the power control module includes a first signal control pin and a second signal control pin, when the power control module receives the plugging signal, the first signal control pin and the second signal control pin are changed from a first level signal to a second level signal, the power control module is configured to output the power signal when the second signal control pin is the second level signal, the first signal control pin is configured to output the control signal, and the control signal is the second level signal.
3. The USB interface control circuit of claim 2, wherein the first signal control pin is configured to convert the first level signal into the second level signal after the second signal control pin is converted into the second level signal.
4. The USB interface control circuit of claim 3, wherein the enable signal is a high signal, the first signal is a low signal, and the second signal is a high signal.
5. The USB interface control circuit of claim 1, wherein the USB connector comprises a first detection pin and a second detection pin; the first detection pin is used for outputting the plugging signal when detecting that the USB connector and the USB equipment are in a positive plugging state; the second detection pin is used for outputting the plugging signal when detecting that the USB connector and the USB equipment are in a reverse plugging state.
6. The USB interface control circuit of claim 1, wherein the switch module comprises:
the first switching tube comprises a control end, a first end and a second end, the control end is electrically connected to the power supply control module and used for receiving the control signal, and the second end is grounded;
one end of the first resistor is electrically connected to a first power supply, and the other end of the first resistor is electrically connected to the first end of the first switch tube; and
the second switch tube comprises a control end, a first end and a second end, the control end is electrically connected to the first end of the first switch tube, the first end is electrically connected to the signal conditioning module and used for outputting the enable signal, and the second end is grounded.
7. The USB interface control circuit of claim 6, wherein the first switch transistor and the second switch transistor are both N-channel field effect transistors, the control terminal of the first switch transistor and the control terminal of the second switch transistor are gates of the N-channel field effect transistors, the first terminal of the first switch transistor and the first terminal of the second switch transistor are drains of the N-channel field effect transistors, and the second terminal of the first switch transistor and the second terminal of the second switch transistor are sources of the N-channel field effect transistors.
8. The USB interface control circuit of claim 1, wherein the signal conditioning module is further configured to stop operating when the enable signal is not received.
9. The USB interface control circuit according to claim 1, further comprising a current detection module electrically connected to the power supply control module and the main control module, wherein the current detection module is configured to detect a current level of the power signal, and the main control module is further configured to determine whether overcurrent protection needs to be activated according to the current level of the power signal.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710130589.0A CN108572935B (en) | 2017-03-07 | 2017-03-07 | USB interface control circuit |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710130589.0A CN108572935B (en) | 2017-03-07 | 2017-03-07 | USB interface control circuit |
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| CN108572935A CN108572935A (en) | 2018-09-25 |
| CN108572935B true CN108572935B (en) | 2022-07-29 |
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| CN201710130589.0A Active CN108572935B (en) | 2017-03-07 | 2017-03-07 | USB interface control circuit |
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| CN114003542B (en) * | 2021-11-09 | 2024-05-31 | 合肥联宝信息技术有限公司 | Signal conditioner, signal conditioning method, electronic device, and storage medium |
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| CN101847082A (en) * | 2009-03-24 | 2010-09-29 | 鸿富锦精密工业（深圳）有限公司 | Control circuit for peripheral device interface |
| CN105988962A (en) * | 2015-01-31 | 2016-10-05 | 鸿富锦精密工业(武汉)有限公司 | Overcurrent detection system and circuit |
| CN106326153A (en) * | 2015-06-29 | 2017-01-11 | 鸿富锦精密工业(武汉)有限公司 | Interface detection circuit |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103064489B (en) * | 2011-10-21 | 2016-03-30 | 华为终端有限公司 | A kind of method and terminal of carrying out internal circuit selection according to USB interface state |
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2017
- 2017-03-07 CN CN201710130589.0A patent/CN108572935B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101847082A (en) * | 2009-03-24 | 2010-09-29 | 鸿富锦精密工业（深圳）有限公司 | Control circuit for peripheral device interface |
| CN105988962A (en) * | 2015-01-31 | 2016-10-05 | 鸿富锦精密工业(武汉)有限公司 | Overcurrent detection system and circuit |
| CN106326153A (en) * | 2015-06-29 | 2017-01-11 | 鸿富锦精密工业(武汉)有限公司 | Interface detection circuit |
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