Interface circuit and power adapter

Abstract

The invention discloses an interface circuit and a power adapter. The interface circuit comprises a controller, a first switch circuit and a pin circuit, wherein the pin circuit comprises a first pin and a second pin; the controller comprises a first input end and a first output end, wherein the first input end is coupled with the first pin; the first switch circuit is configured to be coupled with a first power supply signal and is connected between the first output end and the second pin; the controller is configured to output a first control signal to the first switch circuit based on a first signal of the first input end, and the first switch circuit is configured to output a first power supply signal to the second pin based on the first control signal. The Type-C interface has the technical effects that interface pin breakdown caused by interface plugging operation errors can be avoided, the reliability of the Type-C interface in the use process is improved, and the production cost of the interface is reduced.

Description

Technical Field

[0001] The present application relates to the field of power supply technology, and in particular to an interface circuit and a power adapter. Background Art

[0002] A power adapter is a power supply conversion device for portable electronic devices and electronic appliances. It can be used to convert input AC power into DC power and output it to electronic devices. It has a wide range of supporting applications in the field of electronic technology. However, due to the different power requirements, functions and reference design standards of different electronic devices, there may be differences in the interfaces of electronic devices. With the continuous development of electronic technology, based on many factors such as technology unification and user experience, interfaces are gradually converging. The Type-C (USB Type-C) interface has gradually become widely used due to its small size, double-sided insertion design and support for multiple data transmission and power transmission protocols. However, when a portable electronic device is charged through a power adapter, a higher level of voltage may be directly connected to the Type-C interface due to factors such as interface instability, which may cause damage to the pins and even cause electronic equipment failure. Therefore, the reliability of the interface deserves attention. Summary of the invention

[0003] In view of this, an embodiment of the present application provides an interface circuit and a power adapter to improve the reliability of the power adapter interface. In a first aspect, an interface circuit is provided, including a controller, a first switch circuit and a pin circuit, wherein: the pin circuit includes: a first pin and a second pin; the controller includes: a first input terminal and a first output terminal, the first input terminal is coupled to the first pin; the first switch circuit is configured to couple a first power signal and is connected between the first output terminal and the second pin; the controller is configured to output a first control signal to the first switch circuit based on a first signal at the first input terminal, and the first switch circuit is configured to output a first power signal to the second pin based on the first control signal.

[0004] The above interface circuit can detect whether the pins of the interface are effectively and correctly connected. After determining that the connection is normal, it can then boost the voltage of the electronic device to be powered, thereby ensuring the power supply safety of the power adapter interface and the electronic device connected thereto, and improving the reliability of the use of the power adapter interface.

[0005] Optionally, it also includes: a second switching circuit, the pin circuit also includes: a third pin, and the controller also includes a second output terminal; the second switching circuit is coupled to the second output terminal and connected between the first pin and the third pin; the controller is also configured to output a second control signal to the second switching circuit based on the first signal of the first input terminal, and the second switching circuit is configured to connect the first pin and the third pin based on the second control signal.

[0006] Optionally, the controller is further configured to output one or both of the first control signal or the second control signal based on a preset duration of the first signal.

[0007] The above interface circuit can set a preset duration. When the first signal meets the preset duration, the controller determines whether to output the first control signal or the second control signal, thereby avoiding malfunction of the controller caused by an unreliable first signal, thereby improving the reliability of the interface power supply process.

[0008] Optionally, the first switching circuit includes: a switching tube, the control end of the switching tube is coupled to the first output end, the input end of the switching tube is coupled to the first power supply signal, and the output end of the switching tube is coupled to the second pin; the second switching circuit includes: a single-pole switch, the control end of the single-pole switch is coupled to the second output end.

[0009] Optionally, it also includes: a voltage stabilizing circuit, coupled to the first power signal and the controller, configured to provide a second power signal to the controller based on the first power signal, wherein the voltage of the second power signal is lower than the voltage of the first power signal.

[0010] Optionally, it further includes: a first resistor, one end of which is coupled to the first input end, and the other end of which is coupled to the second power supply signal.

[0011] Optionally, it also includes: a first capacitor, one end of which is coupled to the first input end, and the other end is grounded.

[0012] Optionally, it further includes: a light emitting diode and a second resistor; the controller further includes: an indication terminal coupled to the light emitting diode and the second resistor, and the controller is further configured to turn on the light emitting diode through the indication terminal based on the first signal.

[0013] Optionally, the first signal is a low level signal.

[0014] In a second aspect, a power adapter is provided, comprising: a power supply and an interface; the interface circuit provided in the first aspect above is connected between the power supply and the interface; the power supply is configured to supply power to an electrical device connected to the interface based on control of the interface circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The following is a brief introduction to the drawings used in describing the embodiments of the present application:

[0016] Figure 1 A schematic diagram of a standard Type-C interface structure provided in some embodiments of the present application is shown;

[0017] Figure 2 A schematic diagram of the circuit structure of an interface circuit provided in some embodiments of the present application is shown;

[0018] Figure 3 A circuit structure diagram of another interface circuit provided in some embodiments of the present application is shown;

[0019] Figure 4 A circuit structure schematic diagram of another interface circuit provided in some embodiments of the present application is shown. DETAILED DESCRIPTION

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the specific implementation methods of the present application will be described below with reference to the accompanying drawings. The accompanying drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other accompanying drawings or embodiments can be obtained based on these accompanying drawings or embodiments without paying creative work. The adjustments and improvements made without departing from the concept of the present application all belong to the protection scope of the present application.

[0021] In order to simplify the drawings, each figure only schematically shows the parts related to the embodiments, and they do not represent the actual structure of the product. In addition, in order to simplify the drawings and facilitate understanding, in some figures, only a part of the components with the same structure or function is schematically drawn, and there may be more or less components with the same structure or function in reality.

[0022] In this application, unless otherwise clearly specified and limited, ordinal numbers, such as "first", "second", etc., are only used to distinguish and describe associated objects, and cannot be understood as indicating or implying the relative importance or order between associated objects; in addition, they do not represent the number of associated objects. "Multiple" includes two or more, and other quantifiers are similar. " / " is used to describe the relationship between associated objects, which indicates the "or" relationship between associated objects. "And / or" is used to describe the relationship between associated objects, which includes any combination relationship between associated objects, such as "a and / or b" includes: "alone a", "alone b", or "a and b". "One or more" or "at least one" in multiple objects refers to any object or any combination of multiple objects, such as "one or more of a1, a2, a3" or "at least one of a1, a2, a3" includes: "alone a1", "alone a2", "alone a3", "a1 and a2", "a1 and a3", "a2 and a3" or "a1, a2 and a3".

[0023] The power adapter is a power supply conversion device for portable electronic devices and electronic appliances. It can be used to convert input AC power into DC power and output it to electronic devices. It has a wide range of supporting applications in the field of electronic technology. However, due to the different power requirements, functions and reference design standards of different electronic devices, there may be differences in the interfaces of electronic devices. With the continuous development of electronic technology, based on many factors such as technology unification and user experience, interfaces are gradually converging. For example, the Type-C interface has gradually become widely used due to its small size, double-sided insertion design, and support for multiple data transmission and power transmission protocols. However, when portable electronic devices are connected through a power adapter, when users use the Type-C interface to insert or unplug, they may not be inserted in parallel, but at a certain angle, resulting in the pins between the interfaces not being accurately corresponding, and even pins with different functions and different voltage ratings being connected together, such as the output 20V pin and the input 3.3V pin being connected together. Even if the connection time is short, there is still a risk of causing the device connected to the pin to break down. Please refer to Figure 1, which shows a schematic diagram of a standard Type-C interface structure provided in some embodiments of the present application. Based on the pin definition of the standard Type-C interface, it can be determined that there are adjacent situations of transceiver signals (TX, RX), CC signals and SBU signals, and most of these signals are difficult to support 20V withstand voltage. For example, in the Type-C interface of a two-wire power adapter, 20V and GND signals are output respectively, VBUS is connected to the four pins (pins) A4, B4, A9, and B9 of the Type-C port; GND signal is connected to the four pins A1, B1, A12, and B12 of the Type-C port. They are close to the above-mentioned transceiver signals. If they come into contact with the pins whose input and output exceed their withstand voltage level, the adjacent pins and the corresponding module circuits may be burned, causing the electronic equipment to work abnormally. In order to solve the problem of burning the high-voltage Type-C interface, most of the current solutions are to add dual PD chips, such as adding one PD chip at the adapter end and one PD chip at the machine motherboard end, and using the CC signal on the Type-C for communication handshake. When the two PD chips have successfully handshaked, the power adapter is boosted to 20V output. If the interface is not properly plugged in and the CC signal communication is abnormal, the power adapter will not boost the voltage to 20V output in order to protect the interface and the back-end circuit. However, on the one hand, the cost of the PD chip is relatively high, and the solution of using two PD chips will bring huge challenges to the cost control of the whole machine; on the other hand, there are many PD chip manufacturers and models on the market, and there are compatibility issues when matching chips, resulting in many problems such as boost failure after the connector is normally connected. Therefore, the circuit design of the interface circuit in this application can detect whether the pins of the interface are effectively and correctly connected. After determining that the connection is normal, the power supply to the electronic device to be powered is boosted, thereby ensuring the power supply safety of the power adapter interface and the electronic equipment connected thereto, and improving the reliability of the use of the power adapter interface.

[0024] The following is a description with reference to the accompanying drawings.

[0025] Please refer to Figure 2, which shows a schematic diagram of the circuit structure of an interface circuit provided in some embodiments of the present application. In the network structure, it includes: in the first aspect, an interface circuit 200 is provided, including a controller 210, a first switch circuit 220 and a pin circuit 230, wherein: the pin circuit 230 includes: a first pin PIN1 and a second pin PIN2; the controller 210 includes: a first input terminal IN1 and a first output terminal OUT1, the first input terminal IN1 is coupled to the first pin PIN1; the first switch circuit 220 is configured to couple the first power signal V1, and is connected between the first output terminal OUT1 and the second pin PIN2; the controller 210 is configured to output a first control signal Sc to the first switch circuit 220 based on the first signal S1 of the first input terminal IN1, and the first switch circuit 220 is configured to output the first power signal V1 to the second pin PIN2 based on the first control signal Sc.

[0026] In an embodiment of the present application, when the first pin PIN1 is not in contact with the interface of the electronic device, the first input terminal IN1 of the controller 210 is a preset level, and the first output terminal OUT1 does not enable the first switch circuit 220 to be turned on. When the first switch circuit 220 is turned off, the first power signal V1 cannot supply power to the electronic device through the second pin PIN2 to ensure that the power adapter does not supply power when the pin connection is abnormal, thereby improving the reliability of the interface. After the first pin PIN1 is connected normally, a level jump will be generated at the first input terminal IN1, such as when the preset level is a high level, it jumps to a low level, or when the preset level is a low level, it jumps to a high level. The level jump process can be embodied by the first signal S1, so that the controller 210 enables the control of the conduction of the first switch circuit 220 through the first output terminal OUT1 based on the level change of the first signal S1, and the first power signal V1 supplies power to the electronic device through the first switch circuit 220 and the second pin PIN2. The above interface circuit does not need to set PD chips at both ends of the power adapter and the electronic device respectively. The purpose of interface protection can be achieved through the controller 210. The controller 210 can adopt an application specific integrated circuit (ASIC) or a hardware circuit implemented by a programmable logic device (PLD), such as a field programmable gate array (FPGA) or a microcontroller unit (MCU) or a digital signal processor (DSP). The design selection is made according to the information processing requirements of the control process and the cost control. For example, the microcontroller MCU is used for implementation, which has a lower production cost than the dual PD method.

[0027] Please refer to Figure 3 , which shows a circuit structure diagram of another interface circuit provided in some embodiments of the present application. It also includes: a second switch circuit 240, the pin circuit 230 also includes: a third pin PIN3, and the controller 210 also includes a second output terminal OUT2; the second switch circuit 240 is coupled to the second output terminal OUT2 and connected between the first pin PIN1 and the third pin PIN3; the controller 210 is also configured to output a second control signal Sc2 to the second switch circuit 240 based on the first signal S1 of the first input terminal IN1, and the second switch circuit 240 is configured to connect the first pin PIN1 and the third pin PIN3 based on the second control signal Sc2.

[0028] In an embodiment of the present application, the third pin PIN3 can be connected to the ground terminal of the electronic device interface. When the interface of the power adapter has not yet been connected to the interface of the electronic device, the second switch circuit 240 disconnects the connection between the first pin PIN1 and the third pin PIN3. After the controller 210 determines that the connection is normal through the first signal S1, the controller 210 outputs the second control signal Sc2 to the second switch circuit 240 through the second output terminal OUT2, so that the second switch circuit 240 connects the first pin PIN1 and the third pin PIN3, thereby increasing the reflux capacity of the ground pin of the power adapter port.

[0029] In some embodiments of the present application, the controller 210 is further configured to output one or all of the first control signal Sc1 or the second control signal Sc2 based on the preset duration of the first signal S1. When the controller 210 determines that the first signal S1 exists and the preset duration is met, it outputs the first control signal Sc1 and the second control signal Sc2, which can prevent the first input terminal IN1 from generating a short signal jump due to improper operation during the plugging and unplugging of the interface. The introduction of the preset duration can improve the reliability of the first signal S1, thereby helping the controller 210 to accurately control the conduction of the first switch circuit 220 or the second switch circuit 240. Among them, the first control signal Sc1 and the second control signal Sc2 can be output simultaneously, or there can be a certain time difference between the two. The present application does not limit the order in which the first control signal Sc1 and the second control signal Sc2 are generated. For example, the second control signal Sc2 is output first, so that the third pin PIN3 is grounded, and then the first control signal Sc1 is output, so that the first power signal can be more safely input into the interface of the electronic device. The preset duration can be designed according to actual design requirements without affecting the user experience. For example, the preset duration is 50ms. Under this preset time, it will neither affect the normal plug-in charging nor have a significant impact on the user's experience.

[0030] In some embodiments of the present application, the first switch circuit 220 includes: a switch tube, the control end of the switch tube is coupled to the first output end, the input end of the switch tube is coupled to the first power supply signal, and the output end of the switch tube is coupled to the second pin. The selection of the switch tube, for example, a bipolar junction transistor (BJT), a field effect transistor (FET), an insulated gate bipolar transistor (IGBT), a metal oxide field effect transistor (MOSFET) and other switch tubes can be used, and the design is based on the switching speed, circuit withstand voltage, controller control type and current processing requirements. The second switch circuit 240 includes: a single-pole switch, the control end of the single-pole switch is coupled to the second output end. The controllable switch device selection of the first switch circuit 220 and the second switch circuit 240 can be the same or different, for example, the first switch circuit 220 uses a single-pole switch, the second switch circuit 240 uses a switch tube, or both use a switch tube.

[0031] Please refer to Figure 4 , which shows a circuit structure diagram of another interface circuit provided in some embodiments of the present application. It also includes: a voltage stabilizing circuit 250, coupled to the first power signal V1 and the controller 210, and configured to provide the controller 210 with a second power signal V2 based on the first power signal V1, wherein the voltage of the second power signal V2 is less than or equal to the voltage of the first power signal V1. The voltage stabilizing circuit 250 can be implemented using a low-dropout linear regulator (LDO) or a buck circuit. On the one hand, it can provide the controller 210 with a voltage that meets its operating voltage requirements. For example, if the voltage of the first power signal V1 is 220V, and the operating voltage of the controller 210 is 3.3V, the voltage stabilizing circuit 250 can step down the voltage thereof, and can output a stable 3.3V voltage through negative feedback regulation, further improving the reliability of the circuit.

[0032] Continue to refer Figure 4 In some embodiments of the present application, the present invention further includes: a first resistor R1, one end of which is coupled to the first input terminal IN1, and the other end of which is coupled to the second power signal V2. The first resistor R1 is a pull-up resistor of the first input terminal IN1, and can make the voltage of the first input terminal IN1 high when the first pin PIN1 is not connected (for example, suspended), so that a level jump occurs when the first pin PIN1 is normally connected.

[0033] Continue to refer Figure 4In some embodiments of the present application, the first capacitor C1 is further included, one end of which is coupled to the first input terminal IN1 and the other end is grounded. The first capacitor C1 can be used as a filter capacitor, so that the controller 210 can obtain a stable level change waveform through the first input terminal IN1, thereby accurately controlling the conduction and cutoff of the first switch circuit 220 and the second switch circuit 240.

[0034] Continue to refer Figure 4 , in some embodiments of the present application, it also includes: a light emitting diode D1 and a second resistor R2; the controller 210 also includes: an indication terminal A1, coupled to the light emitting diode D1 and the second resistor R2, and the controller 210 is also configured to turn on the light emitting diode D1 through the indication terminal A1 based on the first signal S1. The light emitting diode D1 can indicate to the user whether the power adapter is connected normally, thereby helping the user to make adjustments when the power adapter is abnormally connected. The connection sequence of the light emitting diode D1 and the second resistor R2 is not limited. The second resistor R2 can be coupled to the second power signal V2 at one end and coupled to the light emitting diode D1 at the other end. Alternatively, the second resistor R2 can be coupled to the light emitting diode D1 at one end and coupled to the second power signal V2 at the other end. The connection mode of the anode and cathode of the light emitting diode D1 can be determined based on the high and low levels that the indication terminal A1 can provide. For example, when the indication terminal A1 provides a low level, the cathode of the light emitting diode D1 is coupled to the indication terminal A1, and the anode is coupled to the second resistor R2.

[0035] Based on the same technical concept, the present application also provides a power adapter, comprising: a power supply and an interface; the interface circuit provided in the first aspect above, connected between the power supply and the interface; the power supply is configured to supply power to an electrical device connected to the interface based on the control of the interface circuit.

[0036] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments. In addition, the above embodiments can be freely combined as needed.

Claims

1. An interface circuit, characterized in that: It includes a controller, a first switch circuit and a pin circuit, wherein: The pin circuit comprises: a first pin and a second pin; The controller comprises: a first input terminal and a first output terminal, wherein the first input terminal is coupled to the first pin; The first switch circuit is configured to couple a first power signal and is connected between the first output terminal and the second pin; The controller is configured to output a first control signal to the first switch circuit based on a first signal at the first input terminal, and the first switch circuit is configured to output the first power signal to the second pin based on the first control signal.

2. The interface circuit according to claim 1, characterized in that: Also includes: a second switch circuit, the pin circuit further comprising: a third pin, the controller further comprising a second output terminal; The second switch circuit is coupled to the second output terminal and connected between the first pin and the third pin; The controller is further configured to output a second control signal to the second switch circuit based on the first signal at the first input terminal, and the second switch circuit is configured to connect the first pin and the third pin based on the second control signal.

3. The interface circuit according to claim 2, characterized in that: The controller is further configured to output one or both of the first control signal or the second control signal based on a preset duration of the first signal.

4. The interface circuit according to claim 3, characterized in that: The first switch circuit includes: a switch tube, a control end of the switch tube is coupled to the first output end, an input end of the switch tube is coupled to the first power signal, and an output end of the switch tube is coupled to the second pin; The second switch circuit includes: a single-pole switch, and a control end of the single-pole switch is coupled to the second output end.

5. The interface circuit according to any one of claims 1 to 4, characterized in that: Also includes: The voltage stabilizing circuit is coupled to the first power signal and the controller, and is configured to provide a second power signal to the controller based on the first power signal, wherein a voltage of the second power signal is lower than a voltage of the first power signal.

6. The interface circuit according to claim 5, characterized in that: Also includes: The first resistor has one end coupled to the first input end and the other end coupled to the second power signal.

7. The interface circuit according to claim 6, characterized in that: Also includes: The first capacitor has one end coupled to the first input end and the other end grounded.

8. The interface circuit according to any one of claims 1 to 4, characterized in that: Also includes: A light emitting diode and a second resistor; The controller further includes: an indication terminal coupled to the light emitting diode and the second resistor, and the controller is further configured to turn on the light emitting diode through the indication terminal based on the first signal.

9. The interface circuit according to any one of claims 1 to 4, characterized in that: The first signal is a low level signal.

10. A power adapter, characterized in that: include: Power supply and interface; The interface circuit according to any one of claims 1 to 9, connected between the power supply and the interface; The power supply is configured to supply power to a powered device connected to the interface based on control of the interface circuit.

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