TW201530303A - Hot plug cable and using method for the cable - Google Patents

Abstract

A hot plug cable includes a first connector connected to a test device, a second connector connected to a motherboard to be tested, and first and second electronic switches. A voltage pin of the first connector is connected to first terminals of the first and second electronic switches. A second terminal of the first electronic switch is connected to a transmitting pin of the first connector. A third terminal of the first electronic switch is connected to a second pin of the second connector. A second terminal of the second electronic switch is connected to a receiving pin of the first connector. A third terminal of the second electronic switch is connected to a third pin of the second connector. A ground pin of the first connector is grounded. A fourth pin of the second connector is grounded. A first pin of the second connector is suspended. The invention is also provided a using method of the cable.

Description

Hot-swappable cable and how to use the cable

The present invention relates to a cable that supports hot swapping and a method of using the cable.

In the design of the motherboard, the interface for testing the motherboard is generally reserved, such as the Universal Asynchronous Receiver/Transmitter (UART) interface. When testing the motherboard to be tested, it is sometimes necessary to use a cable. The reserved interface on the motherboard to be tested is connected to the test device. For example, a test computer tests the motherboard to be tested. However, if the cable that does not support hot swap is directly plugged and unplugged, the motherboard will be tested. The components on them or the cables cause damage.

In view of the above, it is necessary to provide a hot-swappable cable and a method of using the cable to prevent the motherboard to be tested or the cable from being damaged due to hot-swapping of the cable when testing the motherboard to be tested. .

A hot-swappable cable includes a first connector for connecting a test device, a second connector for connecting a motherboard to be tested, and first and second electronic switches, the first connection The voltage pin of the device is connected to the first end of the first and second electronic switches, the second end of the first electronic switch is connected to the sending pin of the first connector, and the third end of the first electronic switch is connected to the a second pin of the second connector, a second end of the second electronic switch is connected to the receiving pin of the first connector, and a third end of the second electronic switch is connected to the third pin of the second connector The grounding pin of the first connector is grounded, the fourth pin of the second connector is grounded, and the first pin of the second connector is suspended; when the first connector is not connected to the testing device, The first ends of the first and second electronic switches receive a low level signal, and the second and third ends of the first and second electronic switches are disconnected. When the first connector is connected to the testing device, the first The first ends of the first and second electronic switches both receive a high level signal, the first and second Communication with the second and the third terminal of the switch.

A method for using a hot-swappable cable as described above, comprising the steps of:

When the cable needs to be used, connect the second connector to the motherboard to be tested;

Connecting the first connector to the test computer, the second and third ends of the first and second electronic switches are in communication; and

The test computer communicates with the motherboard to be tested through the first connector, the first and second electronic switches, and the second connector.

After the second connector is connected to the motherboard to be tested, the hot-swappable cable is connected to the test computer, thereby preventing the first connector from being connected to the first connector. The momentary large current generated when the second connector is connected causes damage to the component or the cable on the motherboard to be tested; and after the first connector is disconnected from the test computer, the second connector is The motherboard to be tested is disconnected, thereby preventing an instantaneous large current generated when the second connector is disconnected when the first connector is not disconnected, thereby causing damage to components or the cable on the motherboard to be tested.

1 is a circuit diagram of a preferred embodiment of a cable for supporting hot swap and a method of using the cable of the present invention.

Referring to FIG. 1 , a preferred embodiment of the present invention supporting the hot-swappable cable 1 includes a first connector 10 , a second connector 20 , and two electronic switches (in this embodiment, two N-channel field effect transistors) Q1 and Q2), two resistors R1 and R2 and a capacitor C1. In the present embodiment, a cable that converts a USB signal into an RS232 signal is taken as an example for description. The first connector 10 is a USB connector for connecting to a test device, such as a USB interface 110 on the test computer 100. The second connector 20 is a Universal Asynchronous Receiver/Transmitter (UART) connector for connecting to the UART interface 210 on the motherboard 200 to be tested.

The voltage pin VCC of the first connector 10 is connected to the gates of the field effect transistors Q1 and Q2 via the resistor R1. The source of the field effect transistor Q1 is connected to the transmission pin TXD of the first connector 10. The drain of the field effect transistor Q1 is connected to the pin 2 of the second connector 20. The source of the field effect transistor Q2 is connected to the receiving pin RXD of the first connector 10, and the drain of the field effect transistor Q2 is connected to the pin 3 of the second connector 20. The capacitor C1 is connected between the gate of the field effect transistor Q1 and the ground, and the resistor R2 is connected between the gate of the field effect transistor Q2 and the ground. The grounding pin GND of the first connector 10 is grounded, the pin 4 of the second connector 20 is grounded, and the pin 1 of the second connector 20 is suspended. The pins 2 and 3 of the second connector 20 respectively correspond to the data receiving pin and the data sending pin of the UART interface 210. The pin 4 of the second connector 20 corresponds to the grounding lead of the UART interface 210. foot.

When the cable 1 is required to be used, the second connector 20 is first connected to the UART interface 210 on the motherboard 200 to be tested, because the first connector 10 is not connected to the USB interface on the computer 100 to be tested. 110. Therefore, the gates of the field effect transistors Q1 and Q2 do not receive a high level signal through the voltage pin VCC of the first connector 10, and the field effect transistors Q1 and Q2 are both turned off. At this time, the first connector 10 is connected to the USB interface 110 of the test computer 100. When the test computer 100 is in operation, the gates of the field effect transistors Q1 and Q2 pass through the voltage of the first connector 10. The pin VCC receives a high level signal, and the field effect transistors Q1 and Q2 are both turned on. The test computer 100 passes through the first connector 10, the field effect transistors Q1 and Q2, and the second connector 20 The test board 200 performs communication to test the board 200 to be tested. That is, after the second connector 20 is connected to the UART interface 210 on the motherboard 200 to be tested, the first connector 10 is connected to the USB interface 110 on the test computer 100, thereby preventing The momentary large current generated when the first connector 10 is connected to connect the second connector 20 causes the component on the motherboard 200 to be tested or the cable 1 to be damaged.

When the cable 1 needs to be removed, the first connector 10 is first disconnected from the USB interface 110 of the test computer 100, and the gates of the field effect transistors Q1 and Q2 are not transmitted through the first connector 10. The voltage pin VCC receives a high level signal, and the field effect transistors Q1 and Q2 are both turned off. The output signal of the test computer 100 cannot pass through the first connector 10, the field effect transistors Q1 and Q2, and the first The second connector 20 is provided to the motherboard 200 to be tested, and the second connector 20 is disconnected from the UART interface 210 on the motherboard 200 to be tested. That is, after the first connector 10 is disconnected from the USB interface 110 of the test computer 100, the second connector 20 is disconnected from the UART interface 210 on the motherboard 200 to be tested, thereby preventing The momentary large current generated when the second connector 20 is disconnected when the first connector 10 is not disconnected causes damage to the component or the cable 1 on the motherboard 200 to be tested.

The hot-swappable cable 1 is connected to the USB interface on the test computer 100 after the second connector 20 is connected to the UART interface 210 on the motherboard 200 to be tested. 110, thereby preventing an instantaneous large current generated when the second connector 20 is connected after the first connector 10 is connected, causing damage to the component or the cable 1 on the motherboard 200 to be tested; and at the first After the connector 10 is disconnected from the USB interface 110 of the test computer 100, the second connector 20 is disconnected from the UART interface 210 on the motherboard 200 to be tested, thereby preventing the first connector 10 from being unbroken. The momentary large current generated by disconnecting the second connector 20 when opening causes the component on the motherboard 200 to be tested or the cable 1 to be damaged.

In summary, the present invention complies with the requirements of the invention patent and submits a patent application according to law. The above description is only the preferred embodiment of the present invention, and equivalent modifications or variations made by those skilled in the art will be included in the following claims.

1‧‧‧ Cable

10‧‧‧First connector

20‧‧‧Second connector

Q1, Q2‧‧‧ field effect transistor

R1, R2‧‧‧ resistance

C1‧‧‧ capacitor

100‧‧‧Test computer

110‧‧‧USB interface

200‧‧‧Testing board

210‧‧‧UART interface

no

1‧‧‧ Cable

10‧‧‧First connector

20‧‧‧Second connector

Q1, Q2‧‧‧ field effect transistor

R1, R2‧‧‧ resistance

C1‧‧‧ capacitor

100‧‧‧Test computer

110‧‧‧USB interface

200‧‧‧Testing board

210‧‧‧UART interface

Claims (7)

A hot-swappable cable includes a first connector for connecting a test device, a second connector for connecting a motherboard to be tested, and first and second electronic switches, the first connection The voltage pin of the device is connected to the first end of the first and second electronic switches, the second end of the first electronic switch is connected to the sending pin of the first connector, and the third end of the first electronic switch is connected to the a second pin of the second connector, a second end of the second electronic switch is connected to the receiving pin of the first connector, and a third end of the second electronic switch is connected to the third pin of the second connector The grounding pin of the first connector is grounded, the fourth pin of the second connector is grounded, and the first pin of the second connector is suspended; when the first connector is not connected to the testing device, The first ends of the first and second electronic switches receive a low level signal, and the second and third ends of the first and second electronic switches are disconnected. When the first connector is connected to the testing device, the first The first ends of the first and second electronic switches both receive a high level signal, the first and second Communication with the second and the third terminal of the switch. The hot-swappable cable according to claim 1, further comprising first and second resistors, wherein the first resistor is connected to the voltage pin of the first connector and the first and second electrons Between the first ends of the switches, the second resistor is coupled between the first end of the second electronic switch and ground. The hot-swappable cable of claim 1, further comprising a capacitor connected between the first end of the first electronic switch and the ground. The hot-swappable cable according to claim 1, wherein the first and second electronic switches are N-channel field effect transistors, and the first and third electronic switches are first to third. The terminals respectively correspond to the gate, source and drain of the field effect transistor. The hot-swappable cable of claim 1, wherein the first connector is a USB connector, and the second connector is a universal asynchronous transceiver connector. A method for using a hot-swappable cable as described in claim 1 of the patent application, comprising the steps of:
When the cable needs to be used, connect the second connector to the motherboard to be tested;
Connecting the first connector to the test computer, the second and third ends of the first and second electronic switches are connected; and the test computer passes the first connector, the first and second electronic switches, and the The second connector communicates with the motherboard to be tested. The method of use as described in claim 6 of the patent scope further includes the steps of:
Disconnecting the first connector from the test computer when the cable needs to be removed;
Disconnecting the second and third ends of the first and second electronic switches;
The output signal of the test computer cannot be supplied to the motherboard to be tested through the first connector, the first and second electronic switches, and the second connector; and the second connector is disconnected from the motherboard to be tested .