CN1211893C - Circuit board with protection function and method for protecting circuit board - Google Patents

Abstract

The present invention provides a circuit board with protection function and a method for protecting the circuit board. When the working voltage of the display card inserted into the control unit is higher than the predetermined voltage of the circuit board, the circuit board cannot be started up with the actuation of the power switch, so as to avoid the circuit board being damaged due to the insertion of a display card that does not meet the specifications.

Description

Circuit board with protection function and method for protecting circuit board

technical field

The invention relates to a circuit board, in particular to a circuit board with protection function and a method for protecting the circuit board, which can prevent components from being damaged due to wrong insertion of a display card.

Background technique

Due to the improvement of semiconductor manufacturing technology, the performance and computing power of semiconductor products have been greatly increased. In order to avoid the disadvantages of increased power consumption and increasing calorific value due to the increase in the performance and computing power of semiconductor products, it has become an inevitable trend for electronic products to develop towards lower power consumption. Due to the relationship between new and old technical specifications, new and old power often appear Specifications of products coexist in the market situation. Taking the main board as an example, the operating voltage of many parts on it has been reduced, and the operating voltage of the chipset on the main board, which is responsible for supervising the data transmission between the microprocessor (CPU) and the periphery, has been reduced. For example, it has gradually become the mainstream. Intel (INTEL) 850/845 chipsets only support graphics cards with a working voltage of 1.5V.

At present, the existing products of graphics cards include graphics cards with different specifications such as Accelerated Graphics Port (hereinafter referred to as AGP) 1x/2x/4x/8x. The working voltage of AGP4X/8X graphics card is 1.5V, which is different from the working voltage of earlier AGP1X/2X graphics card which is 3.3V. Due to the difference in operating voltage, it is necessary to be more careful when inserting the graphics card on the motherboard to avoid burning parts on the motherboard. For example, plug the AGP1X/2X graphics card into the motherboard with the 845/850 chipset and turn it on. The last 3.3V working voltage will be transmitted from the graphics card to the motherboard, which may cause parts of the motherboard such as the chipset to be burned.

In order to avoid misuse by users, it is required that display cards with different operating voltages be provided with a groove on the side of their conductive terminals when they are manufactured, and the slot used to insert the display card in the motherboard is provided with a groove. A protrusion is provided corresponding to the groove of the display card conforming to the operating voltage specification, so that when the display card not conforming to the specification is inserted, it cannot be inserted due to the blocking of the protrusion. However, some display cards did not meet the aforementioned design requirements when they were manufactured. For example, a display card with a working voltage of 3.3V has a working voltage 1.5V identification groove. When the main board is used, the chipset will be burned when the computer is turned on, causing damage to the main board. Therefore, how to avoid improper damage to the mainboard caused by this situation has become a research focus of mainboard manufacturers.

Generally, the display card is provided with a plurality of conductive terminals, and the slot of the main board has pins corresponding to the positions of the conductive terminals, so that the display card can be connected to the main board through the contact between the conductive terminals and the pins. In order to allow smooth communication between the graphics card and the motherboard, the design of the graphics card must follow established regulations. According to regulations, one of the conductive terminals of the display card is designed so that when the operating voltage of the display card is 3.3V, this conductive terminal should be left unconnected, and when the operating voltage of the display card is 1.5V, this conductive terminal should be grounded. In this way, when the display card is plugged into the motherboard, the motherboard can know the working voltage of the display card by detecting the conduction state of the conductive terminal. Therefore, if it is possible to make the motherboard unable to be turned on when the conducting state of the conductive terminals is suspended and unconnected, the occurrence of chipset burnout can be avoided.

Contents of the invention

Therefore, an object of the present invention is to provide a method for protecting a circuit board from mis-inserting a display card that does not meet the specification into the circuit board.

Another object of the present invention is to provide a circuit board with protection function that can reduce the probability of damage.

Another object of the present invention is to provide a circuit board with a protection function that prevents the circuit board from being turned on when a display card that is not suitable for the circuit board is inserted.

Another object of the present invention is to provide a motherboard with a protection function that prevents the motherboard from being turned on when a display card that is not suitable for the motherboard is inserted.

Therefore, the motherboard with protective function of the present invention includes a power switch that can be activated to output a trigger signal to control the startup of the motherboard, a slot for inserting a display card, and a control unit. It is electrically connected to the slot and the power switch to detect whether there is a display card inserted into the slot and the operating voltage of the display card. When the display card is inserted into the slot and the operating voltage of the display card is higher than a predetermined When the voltage is low, the power switch cannot output the trigger signal.

Other features and advantages of the present invention will be clearly understood in the following detailed description of preferred embodiments with reference to the accompanying drawings. In the accompanying drawings:

Description of drawings

FIG. 1 is a circuit block diagram of a preferred embodiment of the present invention.

Fig. 2 is a detailed circuit diagram of the switching circuit of the preferred embodiment of the present invention.

Fig. 3 is a detailed circuit diagram of a preferred embodiment of the present invention.

Figure 4 is a flowchart of the operation of the preferred embodiment of the present invention.

Detailed ways

Please refer to FIG. 1 . FIG. 1 is a schematic block diagram of a preferred embodiment of a motherboard with protection functions of the present invention. It should be noted that although this embodiment is applied to a motherboard, those skilled in the art should understand that it can also be applied to other types of circuit boards. The motherboard 1 of this embodiment includes a chipset 2 , a power circuit 3 , a power switch 4 , a slot 5 and a control unit 6 . In addition, the main board 1 also includes other electronic components such as memory, etc., but since they are widely known by those skilled in the art and are not the focus of improvement in the present invention, they will not be described in detail.

The chipset 2 includes Nanqiao and Northbridge chips and is the control center of the motherboard 1 for supervising the data transmission among all parts in the computer system. The chipset 2 of this embodiment can be an Intel 850 or 845 chipset, and the predetermined voltage supported by the chipset 2 is 1.5V.

The power supply circuit 3 receives power from a power supply (not shown in the figure) and determines whether to supply power to each part 2, 4, 5, 6, 7 on the motherboard 1 according to other factors such as the power switch 4, so as to carry out The computer is turned on, that is, it is used to provide the starting power of the circuit board. Since the power received by the motherboard 1 from the power supply can be roughly divided into a normal power V and a backup power VSB, the power circuit 3 mainly includes a main power circuit and a backup power circuit (not shown). The main power supply circuit provides a general power supply V to each component on the motherboard 1 in good time according to the state of the control unit 6 , so as to provide startup power for the motherboard 1 . And the backup power supply circuit keeps supplying the backup power VSB to the corresponding parts continuously (that is, no matter whether the computer is turned on or not). That is to supply the power required for the operation of the control unit 6 .

The power switch 4 of this embodiment has a button (not shown) exposed on the computer casing and can output a trigger signal to the power circuit 3 when the user presses it, and the power circuit 3 will switch on when receiving the trigger signal. Control the general power supply V to start supplying to each part of the motherboard 1, and then drive the computer to start. FIG. 2 is a detailed circuit diagram of the power switch 4 . The 11th and 12th pins of the power switch 4 are respectively electrically connected to the two ends of the button exposed on the casing, and the button is usually open, so the 11th and 12th pins are not electrically connected, and when the chain is pressed When it is pressed and turned on, the 11th and 12th pins will be turned on, wherein the 11th pin is electrically connected to the backup power supply VSB1 through a resistor R400, and the 12th pin is electrically connected to the power circuit 3. In this way, when the button is pressed, the 11th pin will be connected to the 12th pin, so that the self-standby power supply VSB1 will be transmitted to the power circuit 3 through the 11th and 12th pins, as a trigger signal, to notify The power supply circuit 3 performs the boot operation: on the contrary, when the button is not pressed, the circuit between the 11th and 12th pins is open, and the backup power VSB1 will not flow to the 12th pin, so that the power switch 4 will not output a trigger signal to the Power circuit 3.

Correspondingly referring to FIG. 3 , the slot 5 is available for inserting a display card (not shown in the figure). The slot 5 also has a plurality of pins corresponding to the conductive terminals of the display card. According to regulations, the slot 5 has a first pin T_GND and a second pin TYPEDET, wherein when the display card is plugged into the slot 5, there will be a first conductive terminal and a second conductive terminal on the display card respectively and The corresponding pins are connected. Wherein the first conductive terminal is grounded, and whether the second conductive terminal is grounded is set according to the operating voltage of the display card. In this embodiment, when the operating voltage of the display card is 3.3V (1.5V higher than the predetermined voltage of the motherboard 1), the second conductive terminal is not grounded; and when the operating voltage meets the predetermined voltage of the motherboard 1 (ie The operating voltage of the display card is also 1.5V), and the second conductive terminal is grounded. In this way, the potential change of the first pin T_GND that can be connected to the first conductive terminal can be used to judge whether there is a display card inserted, and the potential change of the second pin TYPEDET that can be connected to the second conductive terminal can be used to judge the display. The operating voltage of the card (described later).

The control unit 6 is electrically connected to the slot 5 and the power switch 4 to detect whether a display card is inserted into the slot 5 and the operating voltage of the display card. When the display card is inserted into the slot 5 and the display card When the operating voltage is higher than the predetermined voltage of the motherboard 1, the power switch 4 cannot output the trigger signal. In this embodiment, the control unit 6 includes a first detection element 61 and a second detection element 62 for detecting whether the slot display card is inserted. The second detection element 62 bridges the first detection element 61 and the power switch 4, and is used to detect whether the operating voltage of the display card is higher than a predetermined voltage, and when the first detection element 61 detects that the display card is inserted into A, it is connected with the second detection element 62 When it is detected that the operating voltage of the inserted display card is higher than the predetermined voltage, the power switch 4 cannot output a trigger signal.

The first detection element 61 includes a first transistor Q43, two serially connected resistors R438, R439, wherein the first base B1 of the first transistor Q43 is electrically connected between the two resistors R438, R439 and the first pin T_GND, wherein the resistor R438 is not The end connected to the first base B1, the first pin T_GND and the resistor R439 is electrically connected to the backup power supply VSB2, and the other resistor R439 is not electrically connected to the first base B1, the first pin T_GND and the resistor 438 The terminal is grounded. The first emitter E1 of the first transistor Q43 is further grounded. In this way, when the display card is not plugged into the slot 4, the first pin T-GND will be at the first potential (approximately VSB*R439/(R438+R439)), and the voltage of the first potential is higher than The start-up voltage (about 0.7V) of the first transistor Q43 causes the first transistor Q43 to be turned on, so that the first collector C1 is connected to the first emitter E1 and grounded. Furthermore, when the display card is inserted into the slot 5, the first pin T-GND is connected to the grounded first conductive terminal on the display card and is at the second potential (i.e., grounded), so that the first transistor Q43 is not conducted, so that the first collector C1 will not be conducted to the first emitter E1. Therefore, it can be determined whether the first pin T_GND is at the first or second potential by using whether the first transistor Q43 turned on by the first detection element is turned on, and then the information of whether the display card is inserted into the slot 5 can be obtained.

The second detecting element 62 has a second transistor Q41 and a resistor R435. The second base B2 of the second transistor Q41 is electrically connected to the resistor R435, the second pin TYPEDET and the first collector C1 of the first transistor Q43, and the second collector C2 is electrically connected to the first collector of the power switch 4 The end of the resistor R400 on the pin 11 that is not electrically connected to the standby power supply VSB (namely, the terminal A in FIG. 2 ), the second emitter E2 is grounded. Therefore, the second transistor Q41 determines whether the first transistor Q43 is turned on or not based on the potential (third potential/fourth potential) of the second pin TYPEDET. When the working voltage of the display card is 3.3V, since the second terminal corresponding to the second pin TYPEDET on the display card is suspended and unconnected, the potential of the second pin TYPEDET is equal to the third potential (about V3. 3), the voltage of the third potential is sufficient to turn on the second transistor Q41. Conversely, when the operating voltage of the display card is 1.5V, the second pin TYPEDET is lowered to the fourth potential (ie, the ground potential) due to the grounding of the second conductive terminal, so that the second transistor Q41 is not turned on.

According to the foregoing, the operating state of the control unit 6 can be roughly divided into the following three conditions, which are discussed in sections:

(1) When the graphics card is not inserted into slot 5 of motherboard 1:

Since the display card is not inserted, there is no need to consider the change of the connection of the first pin T_GND and the second pin TYPEDET to the display card, so the first pin T_GND is at the first potential, that is, the first base B1 is at the first potential, so that The first transistor Q43 is turned on, and the second base B2 of the second transistor Q41 will be grounded, that is, the second pin will also be at the fourth potential, so that the second transistor Q41 is not turned on, so that the power switch 4 still maintains the original state. Increase the action mode of the control unit 6, that is, the 11th pin can still feed the backup power VSB1 into the 12th pin, so that when the button of the power switch 4 is pressed (that is, the 11th and 12th pins are turned on), The trigger signal generated by the backup power supply VSB is output to the power supply circuit 3 through the twelfth pin.

(2) The display card is inserted and the operating voltage of the display card is not higher than the predetermined voltage of the motherboard:

After the display card is inserted into the slot 5, because the first conductive terminal on the display card connected to the first pin T_GND is grounded, the first pin T_GND will be at the second potential (i.e., grounded), and the first transistor Q43 will not conduct and cause It can be considered that the second base B2 is not connected to the first transistor Q43, so the second transistor Q41 only needs to determine whether to conduct according to the potential of the second pin TYPEDET. Thereafter, the second pin TYPEDET is at the fourth potential (that is, grounded) due to the grounding of the second conductive terminal, so that the second transistor Q41 is not turned on, that is, the state is the same as the previous paragraph, and the power switch 4 can still output the trigger signal to Power circuit 3. In this embodiment, the control unit 6 is defined as not activated in the two cases where the display card is not inserted and the display card meets the predetermined voltage of the motherboard 1 .

(3) The display card is inserted and the operating voltage of the display card is higher than the predetermined voltage of the motherboard:

At this time, the first pin T_GND is at the second potential (ground) and the second pin is at the third potential, so that the first transistor Q41 is not turned on and the second transistor Q41 is turned on, so that the eleventh voltage of the power switch 4 The voltage on the A terminal on the pin will be grounded due to the turned-on second transistor Q41 (that is, the second collector C2 is grounded). The switch makes it impossible to output the trigger signal generated by the backup power supply VSB1 to the power circuit 3 no matter whether the button of the power switch 4 is pressed or not, so that the power circuit 3 will not supply the general power V to each part on the motherboard 1 and cannot be turned on , and then can effectively avoid the destruction of the chipset 2 and the main board.

In addition, please refer to FIG. 1 again, the motherboard 1 of this embodiment also includes a warning unit into the warning circuit 7, which is electrically connected to the control unit 6 and starts with the control unit 6 (that is, the third situation mentioned above, the operating voltage is high A display card at a predetermined voltage is inserted into the motherboard 1) and is triggered to output a warning signal to warn the user of wrong insertion. In this embodiment, as shown in FIG. 3 , the warning unit 7 has a third transistor Q42, two resistors R436, R437 and a light emitting diode LED3. One end of the resistor R436 is electrically connected to the second collector of the second transistor Q41 and the terminal A of the eleventh pin of the power switch 4 , and the other end is electrically connected to the third base B3 of the third transistor Q32 . One end of the resistor R437 is electrically connected to the backup power supply VSB4 , and the other end is electrically connected to the third collector C3 of the third transistor Q42 and the P electrode of the light emitting diode LED3 . The third emitter E3 of the third transistor Q3 and the N pole of the light emitting diode LED3 are grounded. Thereby, when the control unit 6 is not started (that is, its second transistor Q41 is not turned on), the third transistor Q42 is turned on due to the feed-in from the standby power supply VSB4 of the power switch, so that the third transistor Q42 of the third transistor Q42 is turned on. The collector C3 can be regarded as being grounded, so that the light-emitting diode LED is not driven. Conversely, when the control unit 6 starts (that is, the second transistor Q41 is turned on), the third base B3 of the third transistor Q42 is grounded and not turned on, so that the backup power VSB4 current of the third collector C3 flows to the light emitting diode. Diode LED3 makes it glow, to remind the user to wrongly insert the message of the display card that does not meet the specifications.

According to the foregoing, with Fig. 4, the control flow of the motherboard 1 of this case is explained. Firstly, in step 81 , it is determined whether the display card is inserted into the slot 5 by using the first detection element 61 . When the display card is not inserted into slot A, that is, the first pin TGND is at the first potential, then go to step 82, the first transistor Q43 of the control unit 6 is turned on and the second transistor Q41 is not turned on, that is, the control unit 6 is not turned on, so that the power switch 4 can be turned on normally. When the display card is inserted into slot A, that is, the first pin T_GND is at the second potential, then go to step 83, and use the second detection element 62 to determine whether the operating voltage of the display card meets the predetermined voltage of the motherboard 1 . And when in step 83, it is determined that the operating voltage of the display card meets the predetermined voltage of the mainboard 1, that is, the second pin TYPEDET is at the fourth potential, the first transistor Q43 and the second transistor Q41 of the control unit 6 are not turned on, and also That is, the control unit 6 is not turned on, so it also enters step 82, so that the power switch 4 can be turned on normally and output a trigger signal. And when in step 83, it is judged that the operating voltage of the display card does not meet the predetermined voltage of the mainboard 1, that is, the second pin TYPEDET is at the third potential, then enter step 84, and the control unit 6 is started, so that the first transistor Q43 is not turned on. The connection with the second transistor Q41 leads to the grounding of the terminal A of the power switch 4 because of its 11th pin, so that it can no longer output the trigger signal to the power supply circuit 3, so that the motherboard 1 cannot be started, thus avoiding the chipset 2 burnt situations occur. Finally, in step 85, the light-emitting diode LED3 of the warning unit 85 is activated to emit light to inform the user that the display card does not meet the predetermined voltage of the motherboard, and then remind the user to replace the display card that meets the predetermined voltage of the motherboard.

To sum up, the motherboard 1 of the present invention can indeed latch the power switch 4 in good time when a display card that does not meet the predetermined voltage of the motherboard is inserted, so that even if the user presses the button of the power switch 4, the power switch 4 still cannot be turned on again. The trigger signal is output so that the power supply circuit 3 cannot be started and cannot feed the general power supply V into each component, that is, it cannot be turned on. In this way, the present invention can indeed solve the problem of the chip set 2 being burned after booting due to wrongly inserting a display card that does not conform to the specifications, thereby achieving the effects of prolonging the product life and facilitating the user to install the display card by himself. In addition, the warning unit 7 also sends out a warning signal when a display card that does not conform to the specification is inserted to remind the user to replace a display card that meets the predetermined voltage of the mainboard 1, thereby improving the convenience of the user's self-installation.

The above is only a preferred embodiment of the present invention, and should not limit the scope of the present invention, that is, all simple equivalent changes and modifications made according to the patent scope of the present invention and the content of the description should still be It belongs to the scope covered by the patent of the present invention.

Claims (24)

1. A motherboard with protection function, comprising: A power switch can be activated to output a trigger signal to control the motherboard to start; a slot for inserting a display card; and A control unit, electrically connected to the slot and the power switch, to detect whether a display card is inserted into the slot and the operating voltage of the display card, when the display card is inserted into the slot and the operating voltage of the display card is high At a predetermined voltage, the power switch cannot output the trigger signal. 2. The motherboard with protection function as claimed in claim 1, wherein the control unit has a first detection element for detecting whether the slot is inserted by the display card. 3. The motherboard with protection function as claimed in claim 2, wherein the slot has a first pin, and when the slot is not inserted into the display card, the first pin is at a first potential , and when the slot is inserted into the display card, the first pin is at a second potential different from the first potential. 4. The motherboard with protection function as claimed in claim 3, wherein the first potential is higher than the second potential, and the first detecting element comprises a first base, a first collector and a The first transistor of the first emitter, the first base is electrically connected to the first pin, the first emitter is grounded, and when the first pin is at the first potential, the transistor is turned on, And when the first pin is at the second potential, the first transistor is not turned on. 5. The motherboard with protection function according to claim 4, wherein the control unit further comprises a second detection element, which bridges the first detection element and the power switch and is used to detect the operating voltage of the inserted display card Whether it is higher than the predetermined voltage, and when the first detection element detects that the display card is inserted and the second detection element detects that the operating voltage of the inserted display card is higher than the predetermined voltage, the power switch cannot output the trigger signal. 6. The motherboard with protection function as claimed in claim 5, wherein the slot has a second pin, and when the operating voltage of the inserted display card is higher than the predetermined voltage, the second pin is located at a third potential, otherwise the second pin is at a fourth potential different from the third potential. 7. The motherboard with protection function according to claim 6, wherein the third potential is higher than the fourth potential, and the second detection element includes a second base, a second collector and a second emitter a second transistor with a polarity, the second base is electrically connected to the second pin and the first collector of the first transistor, the second emitter is grounded, and the second collector is electrically connected to the switching element , and when the second pin is at the third potential, the second detection element is turned on. 8 . The motherboard with protection function according to claim 1 , further comprising a warning unit electrically connected to the control unit and triggered to output a warning signal when the control unit is activated. 9. The main board with protection function as claimed in claim 8, wherein the warning unit has a light emitting element which can light up when the warning unit is triggered. 10. A method for protecting a motherboard, comprising the following steps: Step A: Check if a graphics card is plugged into the motherboard: Step B: detecting whether the working voltage of the display card is higher than the predetermined voltage of the motherboard; and In step C, when it is detected in step A that the display card is inserted into the motherboard and in step B the working voltage of the display card is higher than the predetermined voltage, the motherboard cannot be turned on. 11. The method for protecting a mainboard according to claim 10, further comprising a step D, when it is detected that the display card is inserted into the mainboard in step A and the display card is detected in step B When the operating voltage is higher than the predetermined voltage, a warning signal is output. 12. A motherboard with protection function, comprising: a power switch, which can be turned on to output a trigger signal to control the motherboard to start; a slot for inserting a display card; and A control unit, electrically connected to the slot and the power switch, to detect whether there is a display card inserted into the slot and the operating voltage of the display card, when the display card is inserted into the slot and the operating voltage of the display card is not When a predetermined voltage is met, the control unit is activated so that the power switch cannot output the trigger signal. 13. A method for protecting a motherboard, comprising the following steps: Step A: detecting whether the operating voltage of a plug-in graphics card is higher than a predetermined voltage of the motherboard; and Step B: When it is detected that the operating voltage of the display card is higher than the predetermined voltage, the motherboard cannot be turned on. 14. The method for protecting a motherboard as claimed in claim 13, further comprising a step C: outputting a warning signal when it is detected that the operating voltage of the display card is higher than the predetermined voltage. 15. A motherboard with protection function, comprising: A power switch can be turned on to output a trigger signal to control the motherboard to start: a slot for inserting a display card; and a control unit electrically connected to the slot and the power switch to detect the operating voltage of the display card; Wherein, when the control unit detects that the operating voltage of the display card will cause damage to the motherboard, the control unit prevents the power switch from outputting the trigger signal. 16. The motherboard with protection function according to claim 15, further comprising a warning unit electrically connected to the control unit and outputting a warning signal when the control unit is triggered. 17. A circuit board with protection function, comprising: a power supply circuit for providing the starting power of the circuit board; a slot for inserting a plug-in card, the plug-in card has specifications of high working voltage and low working voltage; and A control unit, electrically connected to the slot and the power circuit, for detecting the working voltage of the card: Wherein, when the control unit detects that the high working voltage of the plug-in card will cause damage to the circuit board, the power supply circuit cannot provide the starting power of the circuit board. 18. The circuit board with protection function according to claim 17, further comprising an alarm unit, which outputs an alarm signal when the control unit is triggered. 19. A method of protecting a circuit board, comprising: providing a power circuit for providing the starting power of the circuit board; A slot is provided for inserting a card, and the card has specifications of high working voltage and low working voltage; A control unit is provided to detect the working voltage of the plug-in card; And when it is detected that the high working voltage of the plug-in card will cause damage to the circuit board, the power supply circuit cannot provide the starting power of the circuit board. 20. The method for protecting a circuit board as claimed in claim 19, further comprising: providing a warning unit, outputting a warning signal when the power supply circuit cannot provide the startup power of the circuit board. 21. A circuit board with chip protection function, comprising: a main power circuit for providing the starting power of the circuit board; a slot for inserting a card, the card has the specifications of high working voltage and low working voltage; a control unit, electrically connected to the slot and the main power circuit, for detecting the working voltage of the card; and A reserve power supply circuit for providing the operating power of the control unit; Wherein, when the control unit detects that the high working voltage of the plug-in card will cause damage to the chips of the circuit board, the main power supply circuit cannot provide the starting power of the circuit board. 22. The circuit board with chip protection function according to claim 21, further comprising a warning unit, when the main power supply circuit cannot provide the startup power of the circuit board, the backup power supply circuit is used to output a warning Signal. 23. A method of protecting a circuit board, comprising: providing a main power circuit for providing the starting power of the circuit board; A slot is provided for inserting a card, and the card has specifications of high working voltage and low working voltage; A control unit is provided to detect the working voltage of the plug-in card; And provide a reserve power supply circuit to provide the operating power of the control unit: When it is detected that the high working voltage of the plug-in card will cause damage to the circuit board, the main power supply circuit cannot provide the starting power of the circuit board. 24. The method for protecting a circuit board according to claim 23, further comprising: providing a warning unit, when the main power supply circuit cannot provide the startup power of the circuit board, using the backup power supply circuit to output a warning Signal.

Images