CN114447881A - Overvoltage protection circuit and C-type universal serial bus connector - Google Patents

Abstract

An overvoltage protection circuit comprises a first connecting pin, a second connecting pin, a third connecting pin, a fourth connecting pin, a cable power supply pin, a first change-over switch, a second change-over switch and a detection unit. The first fixed end of the first switch is coupled to the first connecting pin. The first switch end of the first switch is switched between the cable power pin and the third connection pin. The second fixed end of the second switch is coupled to the second connection pin. The second switch end of the second switch is switched between the cable power pin and the fourth connection pin. The detection unit is used for enabling the first change-over switch and the second change-over switch to be open when detecting that the voltage of the first pin on the first connecting pin or the voltage of the second pin on the second connecting pin is larger than the threshold voltage.

Description

Overvoltage protection circuit and C-type universal serial bus connector

Technical Field

The present invention relates to an overvoltage protection technology, and more particularly, to an overvoltage protection circuit suitable for a universal serial bus (USB Type-C) connector and a universal serial bus connector with overvoltage protection.

Background

The connector can be used for transmitting signals and power between two electronic devices and is a common electronic component on each electronic device. In recent years, a C-Type universal serial bus (USB Type-C) connector has been widely used in various electronic devices because it can provide a very high data transmission rate, and has advantages of being lighter, thinner, shorter, and shorter in size, and having symmetrical sockets for allowing front and back insertion.

However, since the pitch between the terminals in the C-type usb connector is very small, the terminals are easily short-circuited by foreign substances such as liquid or dust, or improper insertion and removal in use. Generally, the bus power terminals in a type C usb connector can support up to 20 volts, but the configuration channel terminals immediately adjacent to the bus power terminals are only used to support about 5 volts. Therefore, once the bus power supply terminal is shorted to the configuration channel terminal, a high voltage will appear on the configuration channel terminal, and this high voltage will damage the downstream circuits coupled to the configuration channel terminal.

Disclosure of Invention

In one embodiment, an overvoltage protection circuit includes a first connection pin, a second connection pin, a third connection pin, a fourth connection pin, a cable power pin, a first switch, a second switch, and a detection unit. The cable power pin is used for receiving cable power. The first fixed end of the first switch is coupled to the first connection pin, and the first switch end of the first switch is switched between the cable power pin and the third connection pin. The second fixed end of the second switch is coupled to the second connection pin, and the second switching end of the second switch is switched between the cable power pin and the fourth connection pin. The detection unit is used for detecting a first pin voltage on the first connection pin and a second pin voltage on the second connection pin. And when the first pin voltage or the second pin voltage is detected to be larger than the threshold voltage, the detection unit enables the first change-over switch and the second change-over switch to be open-circuited.

In one embodiment, a C-type usb connector includes a C-type usb connection interface, a control chip, and an over-voltage protection circuit. The C-type universal serial bus connection interface is provided with a first configuration channel terminal and a second configuration channel terminal. The overvoltage protection circuit is coupled between the C-type universal serial bus connection interface and the control chip. The overvoltage protection circuit comprises a first connecting pin, a second connecting pin, a third connecting pin, a fourth connecting pin, a cable power supply pin, a first change-over switch, a second change-over switch and a detection unit. The first connecting pin is used for connecting a first configuration channel terminal of the C-type universal serial bus connection interface through a first connecting wire. The second connecting pin is used for connecting a second configuration channel terminal of the C-type universal serial bus connection interface through a second connecting wire. The third connecting pin is used for connecting the control chip through a third connecting line. The fourth connecting pin is used for being connected with the control chip through a fourth connecting wire. The cable power pin is used for receiving cable power. The first fixed end of the first switch is coupled to the first connection pin, and the first switching end of the first switch is switched between the cable power supply pin and the third connection pin. The second fixed end of the second switch is coupled to the second connection pin, and the second switching end of the second switch is switched between the cable power pin and the fourth connection pin. The detection unit is used for detecting a first pin voltage on the first connection pin and a second pin voltage on the second connection pin. And when the first pin voltage or the second pin voltage is detected to be larger than the threshold voltage, the detection unit enables the first change-over switch and the second change-over switch to be open-circuited.

Drawings

Fig. 1 is a schematic diagram of a terminal configuration on a type C usb connection interface.

FIG. 2 is a schematic diagram of an embodiment of a type C USB connector.

FIG. 3 is a schematic diagram of an embodiment of a conventional C-type USB connector.

Detailed Description

In order to make the aforementioned objects, features and advantages of the embodiments of the present invention comprehensible, embodiments accompanied with figures are described in detail below.

It will be understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of further features, integers, steps, operations, elements, components, and/or groups thereof.

The terms "first," "second," "third," "fourth," and the like are used to modify elements and are not used to denote a priority or precedence relationship, but rather are used to distinguish elements having the same name.

Fig. 1 is a schematic diagram of a terminal configuration on a C-type usb connection interface, and fig. 2 is a schematic diagram of an embodiment of a C-type usb connector. Referring to fig. 1 and 2, a universal serial bus (USB Type-C) connector 100 is a Universal Serial Bus (USB) connector, and a device connected to one end of a cable (not shown) can establish normal communication with a device equipped with the USB connector 100 regardless of whether the cable is inserted in a forward plug manner or a reverse plug manner. In some embodiments, the C-type usb connector 100 may be, but is not limited to, a mobile phone, a notebook computer, a desktop computer, a mobile power supply, a display, or any other electronic device.

The type-C usb connector 100 may include a type-C usb connection interface 110 and a control chip 120, and the control chip 120 is coupled to the type-C usb connection interface 110. The USB interface 110 is used to interface with a cable, and the control chip 120 is used to control the USB interface 110 according to a communication standard.

Under the specification of the C-type usb, the C-type usb connection interface 110 generally has twenty-four terminals, an upper row of terminals a1-a12 and a lower row of terminals B1-B12. The terminal a1, the terminal a12, the terminal B1, and the terminal B12 are ground terminals. The terminal a2, the terminal A3, the terminal a10, the terminal a11, the terminal B2, the terminal B3, the terminal B10, and the terminal B11 are ultra-high-speed differential signal terminals. The terminal a4, the terminal a9, the terminal B4, and the terminal B9 are bus power terminals. The terminal a5 and the terminal B5 are channel terminals. The terminal A8 and the terminal B8 are sideband use terminals. The terminal a6, the terminal a7, the terminal B6, and the terminal B7 are differential signal terminals. Since the function of each terminal is well known to those skilled in the art, it is not described in detail.

Here, the channel terminals (i.e., terminal a5 and terminal B5) are disposed immediately adjacent to the bus power terminals (i.e., terminal a4 and terminal B4). Generally, the bus power supply terminals can support up to 20 volts (V), but the channel terminals (i.e., terminal A5 and terminal B5) are configured to support only about 5V. Since the distance between the terminals is very small, short circuit is easily generated when the C-type usb connector 100 is connected to or disconnected from a cable, so that a high voltage appears on the configuration channel terminal, and further, a downstream circuit coupled to the configuration channel terminal in the control chip 120 is damaged. In some embodiments, the downstream circuit may be a power distribution controller (PD controller).

In view of this, the present invention provides an overvoltage protection circuit 130 suitable for a C-type universal serial bus connector 100 and a C-type universal serial bus connector 100 equipped with the overvoltage protection circuit 130. The type C usb connector 100 includes a type C usb connection interface 110, a control chip 120, and an overvoltage protection circuit 130. The overvoltage protection circuit 130 is coupled between the C-type usb connection interface 110 and the control chip 120, and the overvoltage protection circuit 130 can disconnect the electrical connection between the configuration channel terminal and the control chip 120 when a high voltage appears on the configuration channel terminal of the C-type usb connection interface 110, so as to prevent the high voltage on the configuration channel terminal from damaging the downstream circuit coupled to the configuration channel terminal in the control chip 120.

In one embodiment, the overvoltage protection circuit 130 includes a first connection pin 131, a second connection pin 132, a third connection pin 133, a fourth connection pin 134, a cable power pin 135, a first switch 136, a second switch 137, and a detection unit 138.

The first connection pin 131 of the overvoltage protection circuit 130 may be connected to the first configuration channel terminal 111 of the C-type usb connection interface 110 through a first connection line 141, and the second connection pin 132 of the overvoltage protection circuit 130 may be connected to the second configuration channel terminal 112 of the C-type usb connection interface 110 through a second connection line 142. The first channel terminal 111 and the second channel terminal 112 are respectively one of the terminal a5 and the terminal B5. For example, when the first configuration channel terminal 111 is the terminal a5, the second configuration channel terminal 112 is the terminal B5. On the contrary, when the first channel terminal 111 is the terminal B5, the second channel terminal 112 is the terminal a 5.

The third connection pin 133 of the overvoltage protection circuit 130 may be connected to the control chip 120 through a third connection line 143, and the fourth connection pin 134 of the overvoltage protection circuit 130 may be connected to the control chip 120 through a fourth connection line 144. In some embodiments, the overvoltage protection circuit 130 is a chip fabricated in an integrated circuit fabrication process. The first connecting pin 131, the second connecting pin 132, the third connecting pin 133, the fourth connecting pin 134 and the cable power pin 135 are all pins (pins) of the chip. In addition, the first, second, third and fourth connection lines 141, 142, 143 and 144 may be printed circuit lines on a Printed Circuit Board (PCB).

The cable power pin 135 of the overvoltage protection circuit 130 is used for receiving a cable power Vconn. In one embodiment, the overvoltage protection circuit 130 may further include a cable power trace L1. The cable power trace L1 includes three endpoints. The first terminal L1a is connected to the cable power pin 135, the second terminal L1b is used as one of the plurality of switching points of the first switch 136, and the third terminal L1c is used as one of the plurality of switching points of the second switch 137. In some embodiments, cable power supply Vconn may be a voltage of 5 volts or 3.3 volts. In addition, cable power trace L1 can withstand at least 300 milliamps (mA) of current.

The first switch 136 of the overvoltage protection circuit 130 has a first fixed end 136a and a first switching end 136 b. The first fixed end 136a of the first switch 136 is fixedly coupled to the first connection pin 131 of the overvoltage protection circuit 130. The first switch end 136b of the first switch 136 can be selectively switched between the cable power pin 135 (i.e., the second end L1b of the cable power trace L1) and the third connection pin 133.

Similarly, the second switch 137 of the overvoltage protection circuit 130 has a second fixed end 137a and a second switching end 137 b. A second fixed end 137a of the second switch 137 is fixedly coupled to the second connection pin 132 of the overvoltage protection circuit 130. The second switch end 137b of the second switch 137 can be selectively switched between the cable power pin 135 (i.e., the third end L1c of the cable power trace L1) and the fourth connection pin 134.

In one embodiment, the first switch 136 can selectively switch the first switch end 136b to the cable power pin 135 or the third connection pin 133 according to the first control signal output by the control chip 120. The second switch 137 can selectively switch the second switch end 137b to the cable power pin 135 or the fourth connection pin 134 according to the second control signal output by the control chip 120. For example, when the control chip 120 determines that the first configuration channel terminal 111 of the C-type usb connection interface 110 is connected to the cc (channel configuration) end of the cable and the second configuration channel terminal 112 is connected to the electronic tag chip (eMark IC) in the cable, the first control signal output by the control chip 120 causes the first switch end 136b of the first switch 136 to be connected to the third connection pin 133, and the second control signal output by the control chip 120 causes the second switch end 137b of the second switch 137 to be connected to the cable power pin 135, so that the cable power Vconn can supply power to the electronic tag chip in the cable through the link path between the second connection pin 132 of the overvoltage protection circuit 130 and the second configuration channel terminal 112 of the C-type usb connection interface 110. When the control chip 120 determines that the second configuration channel terminal 112 of the C-type usb connection interface 110 is connected to the CC terminal of the cable and the first configuration channel terminal 111 is connected to the electronic tag chip in the cable, the second control signal output by the control chip 120 causes the second switch end 137b of the second switch 137 to be connected to the fourth connection pin 134, and the first control signal output by the control chip 120 causes the first switch end 136b of the first switch 136 to be connected to the cable power pin 135, so that the cable power supply Vconn can supply power to the electronic tag chip in the cable through the link path between the first connection pin 131 of the overvoltage protection circuit 130 and the first configuration channel terminal 111 of the C-type usb connection interface 110. Here, since how the control chip 120 determines whether the first configuration channel terminal 111 or the second configuration channel terminal 112 is connected to the CC end of the cable is well known to those skilled in the art, it is not described herein again.

It should be noted that in the embodiment of the present invention, the cable power Vconn can be outputted to the C-type usb connection interface 110 only through one switch, for example, the cable power Vconn can be outputted to the C-type usb connection interface 110 through the first switch 136 or outputted to the C-type usb connection interface 110 through the second switch 137. However, in the conventional C-type usb connector 200 including the usb connection interface 210, the control chip 220 and the over-voltage protection circuit 230, as shown in fig. 3, the cable power Vconn needs to be outputted to the C-type usb connection interface 210 through two switches. For example, the cable power supply Vconn needs to go through the switch 221 to the overvoltage protection circuit 230, and then goes through the switch 231 to the first configuration channel terminal 211 of the C-type usb connection interface 210. For another example, the signal is output to the second channel terminal 212 of the C-type usb connection interface 210 through the switch 232 after passing through the over-voltage protection circuit 230 via the switch 222. Therefore, the voltage drop of the cable power Vconn output by the present invention can be smaller compared to the architecture of the conventional C-type usb connector 200.

The detecting unit 138 of the overvoltage protection circuit 130 is coupled to the first pin 131 and the second pin 132, and the detecting unit 138 is configured to detect a first pin voltage on the first pin 131 and a second pin voltage on the second pin 132. Moreover, when detecting that the first pin voltage is greater than the threshold voltage or the second pin voltage is greater than the threshold voltage, the detecting unit 138 may cause the first switch 136 and the second switch 137 to be open, for example, cause the first switch end 136b of the first switch 136 to be disconnected from the cable power pin 135 and also to be disconnected from the third connection pin 133, and cause the second switch end 137b of the second switch 137 to be disconnected from the cable power pin 135 and also to be connected to the fourth connection pin 134, so as to prevent the high voltage from damaging the downstream circuit. Therefore, the first switch 136 and the second switch 137 in the overvoltage protection circuit 130 provide an overvoltage protection function in addition to the path switching function.

In some embodiments, the threshold voltage may be approximately 6 volts. However, the present invention is not limited thereto, and the threshold voltage may be determined according to the maximum withstand voltage of the downstream circuit coupled to the third connection pin 133 and/or the fourth connection pin 134 of the overvoltage protection circuit 130.

In one embodiment, the control chip 120 may include a first configuration channel pin CC1, a second configuration channel pin CC2, a third switch 121, and a configuration channel logic control unit 122.

The first configuration channel pin CC1 of the control chip 120 may be coupled to the third connection pin 133 of the overvoltage protection circuit 130, for example, through the third connection line 143. The second configuration channel pin CC2 of the control chip 120 may be coupled to the fourth connection pin 134 of the overvoltage protection circuit 130, for example, through a fourth connection line 144.

The third switch 121 of the control chip 120 has a third fixed end 121a and a third switching end 121 b. The third fixed end 121a of the third switch 121 is fixedly coupled to the configured channel logic control unit 122, and the third switch end 121b of the third switch 121 is selectively switchable between the first configured channel pin CC1 and the second configured channel pin CC 2.

The configuration channel logic control unit 122 is capable of controlling the switching of the third switch terminal 121b of the third switch 121 to utilize the signals on the first configuration channel pin CC1 and the second configuration channel pin CC2 by switching the third switch terminal 121 b. For example, the configuration channel logic control unit 122 can know whether the cable is plugged into the C-type USB connector 100 in a forward or backward manner according to the signals on the first configuration channel pin CC1 and/or the second configuration channel pin CC 2. For another example, the configuration channel logic control unit 122 may transmit signals through the first configuration channel pin CC1 and/or the second configuration channel pin CC 2. Since the function of the configured channel logic control unit 122 is well known to those skilled in the art, it is not described herein again.

It should be noted that, since the switching of the output path of the cable power Vconn is already configured in the overvoltage protection circuit 130, the cable power pin, the cable power trace, and the switch for switching the cable power path are not needed to be configured in the control chip 120 of the present invention. In this way, the signal inputted to the configuration channel logic control unit 122 through the first configuration channel pin CC1 or the second configuration channel pin CC2, or the signal outputted from the configuration channel logic control unit 122 to the first configuration channel pin CC1 or the second configuration channel pin CC2, only needs to pass through one switch (i.e., the third switch 121). However, in the conventional C-type usb connector 200, the signals input to the configured channel logic control unit 224 via the pins of the control chip 220 need to pass through two switches. For example, as shown in fig. 3, the switch 221 and the switch 223 are needed, or the switch 222 and the switch 223 are needed.

In some embodiments, the overvoltage protection circuit 130 and the control chip 120 are chips manufactured by different integrated circuit process technologies. Here, since the cable power pin 135 for receiving the cable power Vconn and the cable power trace L1 are disposed in the overvoltage protection circuit 130, the overvoltage protection circuit 130 can be manufactured by a micro-process technology capable of withstanding the voltage of the cable power Vconn. Since the control chip 120 does not need to be configured with cable power pins and cable power traces, the control chip 120 can be manufactured by a more advanced process, such as a nano-fabrication process.

In some embodiments, the over-voltage protection circuit 130 may be fabricated using 0.35 micron process technology. Also, the control chip 120 may be fabricated by a 40 nm process technology.

In summary, embodiments of the present invention provide an overvoltage protection circuit and a C-type usb connector, which utilize a detection unit to detect a first pin voltage on a first connection pin or a second pin voltage on a second connection pin, so as to open a first switch and a second switch when the first pin voltage or the second pin voltage is detected to be greater than a threshold voltage, thereby preventing a high voltage from damaging a downstream circuit. In addition, the embodiment of the invention arranges the cable power supply pin in the overvoltage protection circuit manufactured by micron process technology. Therefore, the control chip of the present invention does not need to be configured with cable power pins and cable power routing, and can be manufactured by advanced processes, such as nano-fabrication, so that the control chip has a smaller area and a lower manufacturing cost. Furthermore, the cable power supply in the embodiment of the invention can be output to the C-type universal serial bus connection interface only through one switch, so that the voltage drop of the cable power supply can be smaller than that of the traditional architecture.

The embodiments of the present invention are disclosed above, but not limited to the scope of the present invention, and those skilled in the art can make various changes and modifications without departing from the spirit and scope of the embodiments of the present invention, therefore, the scope of the present invention shall be determined by the appended claims.

[ notation ] to show

100C type universal serial bus connector

111 first configuration channel terminal

112 second configuration channel terminal

110C type universal serial bus connection interface

120 control chip

121 third transfer switch

121a third fixed end

121b third switch terminal

122 configuration channel logic control unit

130 overvoltage protection circuit

131 first connecting pin

132 second connecting pin

133 third connecting pin

134 fourth connecting pin

135 cable power supply pin

136 first switch

136a first fixed end

136b first switching terminal

137 second change-over switch

137a second fixed end

137b second switch terminal

138 detection unit

141 first connecting line

142 second connecting line

143 third connecting line

144 fourth connecting line

200 traditional C type universal serial bus connector

210C type universal serial bus connection interface

211 first configuration channel terminal

212 second configuration channel terminal

220 control chip

221 change-over switch

222 switching switch

223 diverter switch

224 configuration channel logic control unit

230 overvoltage protection circuit

231 switch

232 switch

A1-A12 terminal

B1-B12 terminal

CC1 first configuration channel pin

CC2 second configuration channel pin

L1 cable power supply routing

L1a first endpoint

L1b second endpoint

L1c third endpoint

Vconn cable supply.

Claims (10)

1. An overvoltage protection circuit comprising:

a first connecting pin;

a second connecting pin;

a third connecting pin;

a fourth connecting pin;

the cable power supply pin is used for receiving a cable power supply;

a first fixed end of the first change-over switch is coupled with the first connecting pin, and the first change-over end of the first change-over switch is switched between the cable power supply pin and the third connecting pin;

a second fixed end of the second change-over switch is coupled with the second connecting pin, and a second change-over end of the second change-over switch is switched between the cable power supply pin and the fourth connecting pin; and

the detection unit is used for detecting a first pin voltage on the first connecting pin and a second pin voltage on the second connecting pin, and when the first pin voltage or the second pin voltage is detected to be greater than a threshold voltage, the detection unit enables the first change-over switch and the second change-over switch to be open-circuited.

2. The overvoltage protection circuit of claim 1, wherein the second switch terminal is connected to the fourth connection pin when the first switch terminal is connected to the cable power pin, and the first switch terminal is connected to the third connection pin when the second switch terminal is connected to the cable power pin.

3. The overvoltage protection circuit of claim 1, wherein the overvoltage protection circuit is adapted for a type C usb connector, the type C usb connector comprising a type C usb connection interface and a control chip, the first connection pin is adapted to connect to a first configuration channel terminal of the type C usb connection interface, the second connection pin is adapted to connect to a second configuration channel terminal of the type C usb connection interface, and the third connection pin and the fourth connection pin are adapted to connect to the control chip.

4. The overvoltage protection circuit of claim 3, wherein the control chip comprises:

a first configuration channel pin for coupling the third connection pin;

a first configuration channel pin for coupling the fourth connection pin;

a third switch end of the third switch is switched between the first configuration channel pin and the first configuration channel pin; and

and a configuration channel logic control unit coupled to the third fixed end of the third switch, and configured to control switching of the third switch end of the third switch.

5. The overvoltage protection circuit of claim 3, wherein the overvoltage protection circuit and the control chip are formed by different process technologies.

6. The overvoltage protection circuit of claim 5, wherein the overvoltage protection circuit is fabricated by micro-fabrication techniques and the control chip is fabricated by nano-fabrication techniques.

7. The overvoltage protection circuit of claim 6, wherein the overvoltage protection circuit is fabricated by 0.35 micron process technology.

8. The overvoltage protection circuit of claim 7, wherein the control chip is fabricated by 40 nm process technology.

9. The overvoltage protection circuit of any one of claims 1 to 8, wherein the cable power supply is at 5 volts or 3.3 volts and the threshold voltage is 6 volts.

10. A type C universal serial bus connector comprising:

the C-type universal serial bus connection interface is provided with a first configuration channel terminal and a second configuration channel terminal;

a control chip; and

an overvoltage protection circuit coupled between the C-type USB connection interface and the control chip, the overvoltage protection circuit comprising:

the first connecting pin is connected with the first configuration channel terminal through a first connecting wire;

a second connection pin connected to the second configuration channel terminal through a second connection line;

the third connecting pin is connected with the control chip through a third connecting wire;

the fourth connecting pin is connected with the control chip through a fourth connecting wire;

the cable power supply pin is used for receiving a cable power supply;

a first fixed end of the first change-over switch is coupled with the first connecting pin, and the first change-over end of the first change-over switch is switched between the cable power supply pin and the third connecting pin;

a second fixed end of the second change-over switch is coupled with the second connecting pin, and a second change-over end of the second change-over switch is switched between the cable power pin and the fourth connecting pin according to a second control signal; and

the detection unit is used for detecting a first pin voltage on the first connecting pin and a second pin voltage on the second connecting pin, and when the first pin voltage or the second pin voltage is detected to be greater than a threshold voltage, the detection unit enables the first change-over switch and the second change-over switch to be open-circuited.

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