Anti-misplug overvoltage protection circuit for Type C interface

Abstract

The utility model relates to a Type C interface anti-misplug overvoltage protection circuit, which comprises a power supply TYPE C interface, a data TYPE C interface, a USB control switch and an overvoltage protection unit, the Type C interface anti-misplug overvoltage protection circuit uses the USB control switch to start overvoltage protection and turn off an input power supply under the condition that a non-PD power adapter is inserted into a USB data interface by mistake, so that the Type C interface anti-misplug overvoltage protection circuit is realized. The computer safety protection circuit is reasonable and simple in circuit structure, easy to implement, low in cost and convenient to popularize.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic circuits, and in particular to an overvoltage protection circuit for preventing mis-insertion of a Type C interface. Background Art

[0002] With the continuous advancement of science and technology, computer products are constantly updated. In order to facilitate carrying, people are increasingly fond of miniaturized and exquisite computer hosts. With the miniaturization of products, in order to meet the needs of end customers, the power input interface of the computer cannot use the traditional 5.5*2.1mm or 5.5*2.5mm DC connector. It is necessary to use a Type C connector with a small size, wide market application, and electrical performance. Using the Type C connector as the power input terminal, the power adapter equipped with the computer must use a PD (Power Delivery) adapter. The cost of a PD adapter is often higher than that of a non-PD adapter, while the non-PD adapter has a fixed power output, such as a non-PD adapter with a fixed output of 19V2A, 19V3A, 12V2A, and 12V3A. There are multiple Type C interfaces on the computer. These Type C interfaces are used for USB data transmission or DP adapter output. The power supply is an external output voltage, and the output voltage is generally 5V. The USB Switch in the Type C interface supports a maximum reverse voltage of 6.8V. If a non-PD adapter is mistakenly inserted, the high voltage will cause the USB Switch of the Type C interface to break down, making the computer host unable to work properly. Utility Model Content

[0003] In view of this, in order to solve the problem of the USB Switch being broken down when the MINI PC is mistakenly plugged into the Type C interface for data transmission using a non-PD adapter, it is necessary to provide a Type C interface anti-misplugging overvoltage protection circuit to prevent damage to the MINI PC.

[0004] A Type C interface anti-misinsertion overvoltage protection circuit comprises a power Type C interface, a data Type C interface, a USB control switch, and an overvoltage protection unit. The data Type C interface is connected to a detection input end of the USB control switch, the detection output end of the USB control switch is connected to the overvoltage protection unit, the output of the overvoltage protection unit is connected to an internal protection circuit of a MINI PC, and the power Type C interface is a power supply input interface of the MINI PC.

[0005] Furthermore, when a non-PD adapter is mistakenly inserted into the data TYPE C interface, the USB control switch detection input terminal detects an abnormally high voltage, and the USB control switch detection output terminal activates the overvoltage protection unit, prohibiting the power supply voltage of the non-PD adapter from being input into the internal circuit of the MINI PC, thereby achieving the purpose of protection.

[0006] Furthermore, when the non-PD adapter is inserted into the power TYPE C interface, the USB control switch does not work, and the non-PD adapter power supply supplies power to the MINI PC.

[0007] In the above-mentioned Type C interface anti-misinsertion overvoltage protection circuit, the USB control switch detection input end detects that the data TYPE C interface is mistakenly inserted into a non-PD adapter, and the USB control switch output controls the overvoltage protection unit to work, prohibiting the power voltage of the non-PD adapter from being input into the internal circuit of the MINI PC, thereby achieving the purpose of protecting the MINI PC. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 It is a principle block diagram of the Type C interface anti-misinsertion overvoltage protection circuit of an embodiment of the utility model.

[0009] Figure 2 It is a circuit schematic diagram of the Type C interface anti-misinsertion overvoltage protection circuit of an embodiment of the utility model.

[0010] Figure 3 It is a circuit schematic diagram of the Type C interface anti-misinsertion overvoltage protection circuit of the second embodiment of the present utility model. DETAILED DESCRIPTION

[0011] The Type C interface anti-misinsertion overvoltage protection circuit provided by the embodiment of the utility model will be described in detail below in conjunction with specific embodiments and drawings.

[0012] See also Figure 1 and Figure 2 , shows a Type C interface anti-misinsertion overvoltage protection circuit provided by an embodiment of the utility model, including a TYPE C interface USB J2, a TYPE C interface USB J1, a USB control switch U3, and a MINI PC chip U2.

[0013] Specifically, in this embodiment Figure 2 In the circuit schematic diagram, the Type C interface anti-misinsertion overvoltage protection circuit includes a power management chip U1, U2 is the Intel atom SOC chip in the MINI PC computer, the USB control switch U3 is an adjustable current limit control load switch, the model of the USB control switch U3 is FA7615, FA7615 has a 28V overvoltage protection function, USBJ1 is a Type C interface for USB data output of the MINI PC computer, and USB J2 is a Type C interface for MINI PC computer power input.

[0014] USB J2 has pin A9, pin B9, pin A12, and pin B12. Pin A9 and pin B9 of USB J2 are connected to the power supply +V12IN network. The input 12V is connected to the power management chip U1. Pin A12 and pin B12 are connected to the ground pin GND of USB J2.

[0015] USB J1 is a Type C connector. USB J1 has pins A6, A7, B6, B7, A12, and B12. Pins A6, A7, B6, and B7 of USB J1 are used to connect USB2_P4_DP and USB2_P4_DN. Pins A4, A9, B4, and B9 of USB J1 are connected to the power supply +V5P0A_USB_P1 network. Pins A12 and B12 of USB_J2 are connected to GND.

[0016] Specifically, the power management chip U1 has an input pin 1 and an output pin 2, and converts the 12V input from the adapter into +V5P0A to supply power to the USB control switch U3.

[0017] The chip U2 is an Intel Atom chip in a MINI PC computer. The Atom chip U2 has pin 1, pin 2, and pin 3. Pin 1 of the chip U2 is connected to the USB J1 pin D+, and pin 2 of the chip U2 is connected to the USB J1 pin D-. The PM_SLP_S4_N signal output by pin 3 of the chip U2 is used to control the opening and closing of the USB control switch U3. When the PM_SLP_S4_N signal is at a high level, the USB control switch U3 is turned on, and 5V is directly output to USB J1. When the PM_SLP_S4_N signal is at a low level, the USB control switch U3 is turned off, and no voltage is output.

[0018] The USB control switch U3 has a power output pin 1, a GND pin 2, an EN pin 4, a current output control pin 5, and a power input pin 6. The GND pin 2 is grounded. The power output pin 1 of the USB control switch U3 is connected to the positive electrode of the output capacitor SEC4 and one end of the capacitor SEC44. The other end of the capacitor SEC44 and the negative electrode of the capacitor SEC4 are grounded. The power input pin 6 of the USB control switch U3 is connected to the positive electrode of the input capacitor C9773 and the output pin 2 of the power management chip U1. The negative electrode of the input capacitor C9773 is grounded. The power management chip U1 outputs 5V power to the power input pin 6 of the USB control switch U3. The power output pin 1 of the USB control switch U3 is connected to the USB J1 pin A4 and pin A9. When the USB control switch U3 is turned on, it outputs 5V to the USB J1 Type C connector interface. When the USB J1 is mistakenly inserted into a non-PD adapter and the input voltage is less than 28V, the chip is protected to prevent the voltage of the non-PD adapter from being input internally. The EN pin 4 is the USB The control pin of the control switch U3 is connected to the pin 3 of the Atom chip U2. When the pin 3 of the Atom chip U2 is at a high level, the USB control switch U3 is turned on and outputs 5V. When the pin 3 of the Atom chip U2 is at a low level, the USB control switch U3 is turned off.

[0019] The USB control switch U3 has an output current control function. The output current of the USB control switch U3 is realized by connecting the current output control pin 5 to an adjustable resistor. The current output control pin 5 is connected to the adjustable resistor AR228. The other end of the adjustable resistor AR228 is grounded. By adjusting the resistance value of the adjustable resistor AR228, the output limiting current of the USB control switch U3 can be adjusted. In this circuit design, AR228 uses a 14K resistor to limit the output current of the USB control switch U3 to 1.5A.

[0020] Figure 3 This is a circuit diagram of the second embodiment of the Type C interface anti-misinsertion overvoltage protection circuit of the utility model. Chip 9U1 is Intel's X86 SOC chip. Pin 1# outputs USB2_P1_CNN and pin 2# outputs USB2_N1_CNN connected to USB_J1. PM_SLP_S4_N of pin 3# of the X86 SOC chip is used to control the opening and closing of the 5V voltage +V5P0A of the USB switch chip 9U3. When the PM_SLP_S4_N signal is at a high level, the USB switch chip 9U3 is turned on, and +V5P0A is directly output to USB_J1 through the USB switch 9U3. When the PM_SLP_S4_N signal is at a low level, the USB switch chip 9U3 is turned off without any voltage output.

[0021] The chip 9U2 of MINI PC is the power management unit PMU in MINI PC, which outputs +V5P0A and provides 5V voltage to power USB_J1.

[0022] The model of USB Switch chip 9U3 is FA7615, which supports 28V overvoltage protection and has a load switch with adjustable current limit control. Pin 1# is the power output pin, which is connected to the external output filter capacitors 9C1, 9C2, and 9C3, and outputs 5V to provide power to the Type C interface USB_J1. Pin 2# is the GND pin; Pin 3# is OCB and is not used; Pin 4# is the control pin of the USB Switch chip, connected to PM_SLP_S4_N. When PM_SLP_S4_N is high, the USB Switch is turned on, and Pin 1# outputs 5V voltage to the outside. When PM_SLP_S4_N is low, the USB Switch is turned off. Pin 5# ISET is the current output control pin of the USB Switch chip 9U3. The output current of the USB Switch chip 9U3 is adjusted by the resistance value of the adjustable resistor AR228. The resistance value of the designed resistor AR1 in the circuit of the second embodiment is 14K. According to the current calculation formula I=21000 / Rset (Ω), the current design value of the circuit of the second embodiment is 21000 / 14000=1.5A, and the output current is limited to 1.5A. Pin 6# is the power input pin VIN, which is connected to the power supply +V5P0A, and the external input capacitor C1 has a capacitance value of 10uf / 6.3V.

[0023] USB_J1 is a 16-pin Type C connector. The A6 and B6 pins of USB_J1 are used to connect to USB2_P1_CNN, and the A7 and B7 pins of USB_J1 are used to connect to USB2_N1_CNN.

[0024] When the non-PD power adapter is mistakenly plugged into the USB_J1 interface, the input voltage of the A4, A9, B4, and B9 pins on the USB_J1 interface is 12V or 19V, and the 1# pin of the USB Switch 9U3 is directly connected to the A4, A9, B4, and B9 pins on the USB_J1 interface. At this time, the voltage of the non-PD power adapter will be directly output to the output pin 1# pin OUT of the chip 9U3. Since the maximum withstand voltage value of the 1# pin OUT of the chip 9U3 is 28V, the 12V or 19V voltage input from the non-PD power adapter will not damage the USB Switch chip 9U3. The 12V or 19V voltage input from the non-PD power adapter is isolated and disconnected by the USB Switch chip 9U3, and the 12V or 19V voltage input from the non-PD power adapter cannot directly reach the 6# pin of the chip 9U3, thereby preventing the non-PD power adapter mistakenly plugged into USB_J1 from damaging the internal components of the MINI PC motherboard power management unit 9U2.

[0025] The above-mentioned Type C interface anti-misinsertion overvoltage protection circuit utilizes the USB Switch control switch to isolate and shut down the input power voltage of the non-PD adapter when the non-PD power adapter is mistakenly inserted into the USB data interface. The power voltage of the non-PD adapter cannot enter the computer's back-stage circuit, and the overvoltage protection function is activated to prevent damage to the internal components of the PC, thereby ensuring the safety of the computer. The circuit of the utility model is simple, easy to produce, low-cost, and easy to promote.

[0026] It should be noted that the present invention is not limited to the above-mentioned embodiments. According to the creative spirit of the present invention, those skilled in the art may also make other changes. These changes made according to the creative spirit of the present invention should be included in the scope of protection required by the present invention.

Claims

1. A Type C interface anti-misinsertion overvoltage protection circuit, characterized in that: It includes a power TYPE C interface, a data TYPE C interface, a USB control switch, and an overvoltage protection unit. The data TYPE C interface is connected to the USB control switch detection input end, the USB control switch detection output end is connected to the overvoltage protection unit, the overvoltage protection unit output end is connected to the MINI PC internal protection circuit, and the power TYPE C interface is the MINI PC power supply input interface.

2. The Type C interface anti-misinsertion overvoltage protection circuit according to claim 1, characterized in that: When a non-PD adapter is mistakenly inserted into the data TYPE C interface, the USB control switch detection input terminal detects an abnormally high voltage, and the USB control switch detection output terminal activates the overvoltage protection unit, prohibiting the power voltage of the non-PD adapter from being input into the internal circuit of the MINI PC, thereby achieving the purpose of overvoltage protection.

3. The Type C interface anti-misinsertion overvoltage protection circuit according to claim 2, characterized in that: When the non-PD adapter is inserted into the power TYPE C port, the USB control switch does not work, and the non-PD adapter power supply provides normal power to the MINI PC.

Images