CN100488085C - Method and system for hot plug of functional board - Google Patents

Abstract

Method for plugging a functional board includes steps: plugging part of functional board into connector in motherboard; making the functional board connect to power lines on the motherboard electrically, and keeping in state of not electrical connection between functional board and motherboard for a certain period; inserting the functional board into motherboard totally, making signal lines on functional board connect to signal lines on the motherboard electrically. Steps of pulling out a functional board are as following: disconnecting signal lines of functional board from signal lines of motherboard; after a time gap, disconnecting power lines of functional board and motherboard. The invention also discloses the system for hot plug of functional board.

Description

Function board hot swap method and system

technical field

The invention relates to a function board hot plug method and system in the communication field.

Background technique

Function board (or veneer) hot-swapping mainly refers to hot plugging and unplugging of function boards, that is, when the chassis is powered on, inserting or unplugging a single board from the chassis is the same as hot-swapping, Heat exchange has the same meaning. As a technology, single-board hot-swapping is widely used in various electronic equipment. For example, during the testing and maintenance of telecommunication equipment, since the system cannot be interrupted, hot-swapping of single-boards is common. Through hot plugging, users can flexibly change the configuration of the device without cutting off the power supply, thereby minimizing the business loss caused by cutting off the power supply.

Single boards with high-level protection requirements require that live plugging and data exchange can be performed simultaneously, that is, plugging and unplugging operations under any circumstances will not destroy data, and of course will not damage devices. In order to meet these requirements, the protective design must meet three requirements at the same time:

First, block the current (I _OFF ), that is, the signal pin voltage of the chip is required to be 4.5V, and when the power supply voltage is 0V, the current flowing from the signal pin must be less than the specified value, and the chip can be guaranteed within the specified value. Not subject to electrical damage.

Second, device power-on tri-state (PU3S).

Third, the device has a precharge I/O function.

Existing hot-swap implementation solutions generally use technologies such as devices that resist electrical shocks of hot-swap, protection circuits, and power supply slow-on circuits. However, this structure has disadvantages such as high cost of the single board.

Contents of the invention

The purpose of the present invention is to provide a simple and easy hot-swapping method for a function board, thereby reducing the cost of a single board.

Another object of the present invention is to provide a system using the above functional board.

Technical scheme of the present invention is:

A hot-swapping method for a function board, in which steel balls, springs and barrels are arranged on one side of the guide slideway of the machine frame, and openings are set at the corresponding positions of the guide slideway, so that a part of the steel ball is raised and higher than the guide slideway, and on the function board Install the positioning groove on the top;

Inserting a function board includes steps:

A. Insert the function board part into the motherboard connector, and use the resistance generated by the steel ball falling into the positioning groove to stop the insertion, so that the function board and the power line of the motherboard are electrically connected and the signal line is not electrically connected for a certain period of time. So that the function board can use this time to complete the power-on process;

B. Fully insert the function board into the motherboard connector, so that the signal line of the function board is connected with the signal line of the motherboard;

Pulling out the function board includes steps: disconnect the signal line of the function board from the mother board, use the resistance generated by the steel ball falling into the positioning groove to make the function board and the signal line of the mother board disconnected and then pause, and disconnect the function board after a certain period of time. The power cable from the board to the motherboard is disconnected.

A system capable of hot-swapping function boards, including a machine frame, a function board and a motherboard arranged in the machine frame, and a connector connecting the function board and the motherboard;

One part of the pins of the connector is a long pin, and the other part is a short pin, the long pin is defined as a power line, and the short pin is defined as a signal line; one side of the machine frame guide slideway is provided with Steel balls, springs and sleeves, openings are provided at the corresponding positions of the guide slideway, so that a part of the steel ball is raised and higher than the guide slideway, and a positioning groove is installed on the function board. During the process of inserting or pulling out the function board, use The resistance produced by the steel ball falling into the positioning groove makes the insertion or extraction stop, and controls the order in which the long pins and short pins contact the corresponding slots.

The invention adopts a simple method, that is, adopts long and short pins and control components to control the contact sequence and time interval of the single-board power supply, ground wire, and signal wire, so as to achieve the purpose of using high protection level devices and circuits with the same live plugging protection purpose, which greatly saves The cost of the single board is reduced, and the application range of non-hot-swappable devices is expanded.

Description of drawings

Fig. 1 Schematic diagram of the structure of long and short pin connectors;

Fig. 2 is a schematic structural diagram of a hot-swappable single board of the present invention;

Figure 3 schematic diagram of device damage;

Figure 4 is a schematic diagram of the chip I/O model;

Figure 5 is a schematic diagram of the installation position of the positioning steel ball;

Figure 6 is a schematic diagram of the hot-swapping process of a single board;

FIG. 7 is a structural schematic diagram of extending the contact time interval of the single-board power supply, ground wire, and signal wire by using mechanical pins.

Detailed ways

The invention meets the following three requirements of single-board hot-swapping protection with a simple and convenient mechanical method:

First, the blocking current (IOFF), that is, the signal pin voltage of the chip is required to be 4.5V, and when the power supply voltage is 0V, the current flowing from the signal pin must be less than the specified value, and the chip can be guaranteed to be within the specified value. subject to electrical damage. Second, device power-on tri-state (PU3S). Third, the device has a precharge I/O function.

The hot-swapping method of the present invention is: in the process of inserting the single board into the mother board, let the power line of the function board and the mother board be electrically connected first (that is, the signal line is in non-electric connection) and keep it for a certain period of time, and the function board uses Complete the power-on process at this time; then fully insert the function board into the motherboard connector, so that the signal line of the function board is connected with the signal line of the motherboard.

The present invention is described in detail below in conjunction with accompanying drawing:

Referring to FIG. 1 , the connector for connecting the single board and the motherboard includes a plug 1 and a socket 2 , the plug 1 is fixed on the single board, and the socket 2 is fixed on the motherboard 3 . The plug 1 is provided with a long pin 5 and a short pin 4 , and the socket 2 has a slot 6 matched with the long pin 5 and the short pin 4 . The number of long needles and short needles can be set as required.

Referring to a kind of system shown in Fig. 2, this system comprises machine frame 10, the function board 9 and motherboard 3 that are arranged in the machine frame, and the connector (structure shown in Figure 1) that connects function board and motherboard, this The connector includes a plug 1 and a socket 2. Wherein: the long pin 5 in the plug 1 is defined as a power line (including positive and negative wires), and the short pin 4 is defined as a signal line (that is, other signal lines except the power line). Two pairs of ends of the panel 8 of the function board 9 are provided with screws 12 respectively, and screw holes are provided at corresponding positions on the machine frame 10. 9 is fixed on the machine frame 10.

When the function board 9 is inserted into the socket 2 of the motherboard 3, the function board 9 enters the machine frame along the guide slide 11, and the function board 9 cannot be directly inserted into the motherboard 3 due to the hindering effect of the screw 12 touching the machine frame 10 , the signal line and the power line (comprising positive and negative lead wires) on the plug 1 of the function board 9 cannot be connected with the charged motherboard 3, and the screw 12 must be rotated to be inserted into the socket 2 and electrically contacted. The long pin 5 is in contact with the short pin 4 before the board is inserted. That is to say, in the process of slowly inserting the function board 9 into the motherboard 3, the power line (including positive and negative pole lines) of the function board 9 first contacts the power line on the motherboard 3, and the single board is charged, which is equivalent to that of the function board 9. Independent power-on, the signal lines are only contacted and electrically connected after the power-on is completed.

Correspondingly, in the process of pulling out the function board, the long pin 5 is separated later than the short pin 4, that is, the signal line of the function board 9 and the motherboard 3 is disconnected first, and then the power line is disconnected after a certain time interval.

If the function board has not completed the power-on process, the contact of the signal line will occur, and a large current inrush from the signal line to the power supply will inevitably occur, resulting in damage or latch-up of the interface device of the function board. As shown in FIG. 3 , the voltage of the power supply VCC on the function board is lower than the power supply voltage of the motherboard, and the signal pins are in contact with the signals of the motherboard. If the electrical protection method is used, the devices on the board must have the IOFF function. And the present invention is to utilize the power line to contact first, and the manual rotation screw makes the power line come into contact with the longer time interval between signal line contacts to achieve the same purpose. Assuming that the length difference between the long pin and the short pin of the board is 2mm, the pitch of the screw is 0.5mm, and the fastest manual rotation of the screw is 0.5 seconds, it takes at least 2 seconds from the long pin to the short pin. At this point, the board has completed the power-on process, that is, the power supply voltage of the board is the same as that of the motherboard.

The second requirement for single-board hot-swap protection is the power-on tri-state of the interface device. That is, the signal pin remains in a high-impedance state until the power supply voltage rises to the specified value, and will output according to the set state after the power supply voltage exceeds the specified value. When the board is powered off, the output remains at the driving logic level until the power supply voltage drops to a predetermined voltage value, and then becomes a high-impedance state. Because the method of the present invention completes before the single-board power supply is powered on, the signal line has not been in contact yet, that is, the signal at both ends of the connector is in an isolated state (being an ideal high-impedance state); The line is disconnected later than the signal line, which meets the above-mentioned requirement that the signal line maintains a logic level before the power supply voltage drops by a predetermined voltage value, and then becomes a high-impedance state. Therefore, the method of the present invention meets the requirement of power-on tri-state.

The third requirement for single-board hot-swap protection enables the device to have pre-charged I/O capabilities. Due to the parasitic capacitance of the pins of the interface chip when the board is inserted, and the difference in the signal levels at both ends of the connector, the charging and oscillation process of the I/O pins will occur during the insertion process, and this transient charging current will also Generates a momentary glitch on the corresponding bus signal. Therefore, data transmission on the bus may be interrupted during hot plugging and unplugging of the single board. The so-called pre-charge I/O is to charge the I/O pin of the plug-in module to a certain level before the signal line contacts when plugging and unplugging, so that the interference can be reduced when the signal lines are in contact. Because the method of the present invention enables the power supply of the single board to be powered on before the contact of the signal line, and the interval between them is relatively long, and there is always a certain equivalent resistance between the chip power supply and the signal pin. As shown in Figure 4, the power supply charges the parasitic capacitance on the signal pin through this resistor. Assuming that the resistance R is 100MΩ and the parasitic capacitance C is 10pF, it only takes 3ms for the parasitic capacitance of the I/O pin to charge to the power supply voltage. Therefore, the method of the present invention can also achieve and meet the purpose and requirement of precharging I/O.

The above method can fully meet the three requirements of the single board hot-swap protection, therefore, the hot-swap function can be realized.

In the present invention, control components such as mechanical pins or steel balls can also be used to insert the function board into a predetermined position in the connector of the mother board. At this position, there is a slight pause due to mechanical resistance, and only the power supply of the function board The power line is connected to the motherboard, that is, the power-on process is completed, and then the function board can be fully inserted into the motherboard connector to make the signal line electrically connected, that is, to extend the time interval between the power supply, ground wire, and signal line of the single board.

Refer to Figure 5 for the structure of using steel balls to extend the contact time interval of the single-board power supply, ground wire, and signal wire. Steel ball 14, spring 16 and sleeve barrel 13 are installed on one side of machine frame guide slideway 15, and guide slideway 15 corresponding position is provided with opening, and a part of steel ball 14 is raised and higher than guide slideway 15.

Referring to FIG. 6 , a positioning groove 18 is installed on the single board 9 , and when the positioning steel ball 14 falls into the positioning groove 18 , the power and ground pins are in contact, but the signal pins are not. In this way, during the insertion or extraction process of the veneer 9, the resistance generated by the falling of the steel ball 14 into the positioning groove 18 makes the insertion or extraction pause, thereby prolonging the time interval between the successive contact of the power supply, the ground wire and the signal wire.

Refer to Figure 7 for the structure of using mechanical pins to extend the contact time interval of the single-board power supply, ground wire, and signal wire. A V-shaped slider 18, spring 16 and sleeve 13 are installed on one side of the guide slideway 15, and the mechanical pin 17 is installed on the veneer. When the mechanical pin 17 fell into the V-shaped groove of the V-shaped slider, the power supply It is in contact with the ground pin, but the signal pin is not. In this way, during the insertion or extraction process of the single board, resistance will also be generated, so that the insertion and extraction will pause, thereby prolonging the time interval between the power supply, the ground wire and the signal wire successively contacting each other.

For the present invention, the control components for controlling the sequence of contacting the long pins and the short pins with the corresponding sockets can also be arranged on the plug and the socket. For example: connect the plug and the single board with flexible wires, set screws on the plug, and set corresponding screw holes on the socket, so as to directly control the plug for hot swapping.

Claims (2)

1. A function board hot-swapping method, characterized in that: Set steel balls, springs and sleeves on one side of the guide slideway of the machine frame, set openings at the corresponding positions of the guide slideway, make a part of the steel ball bulge and be higher than the guide slideway, and install positioning grooves on the function board; Inserting a function board includes steps: A. Insert the function board part into the motherboard connector, and use the resistance generated by the steel ball falling into the positioning groove to stop the insertion, so that the function board and the power line of the motherboard are electrically connected and the signal line is not electrically connected for a certain period of time. So that the function board can use this time to complete the power-on process; B. Fully insert the function board into the motherboard connector, so that the signal line of the function board is connected with the signal line of the motherboard; Pulling out the function board includes steps: Disconnect the signal line between the function board and the mother board, use the resistance generated by the steel ball falling into the positioning groove to make the signal line between the function board and the mother board disconnected, and then stop. After a certain period of time, connect the power line between the function board and the mother board disconnect. 2. A system capable of hot-swapping function boards, including a machine frame, a function board and a motherboard arranged in the machine frame, and a connector connecting the function board and the motherboard; it is characterized in that the plug of the connector One part of the needle is a long pin, and the other part is a short pin. The long pin is defined as a power line, and the short pin is defined as a signal line; one side of the frame guide slideway is provided with steel balls, springs and sleeves , the corresponding position of the guide slideway is provided with an opening, so that a part of the steel ball is raised and higher than the guide slideway, and a positioning groove is installed on the function board. During the process of inserting or pulling out the function board, the steel ball falls into the positioning groove. The resulting resistance pauses insertion or removal, controlling the sequence in which long and short pins make contact with their respective sockets.

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