CN103617908B - The keyboard safety protection device of payment terminal and method - Google Patents

Abstract

The present invention provides a keyboard security protection method for a payment terminal. The security processor of the payment terminal drives and outputs two sets of independent security network detection signals, passes through two sets of cross-arranged security network detection contacts around the PCB board of the keyboard, and then passes through The same two sets of cross-arranged safety network detection contacts on the FPC protective film of the dome and the corresponding two-layer network wiring are combined with the extrusion of the limit post to form a path, and then the detection signal is returned to the safety of the safety processor. Detect the input circuit, so as to realize the cross interlock of the safety detection signal to protect the safety of the keyboard. The present invention also provides a keyboard safety protection device for a payment terminal. The present invention can realize a cross-interlock safety protection mechanism, and through safety network detection and safety switch detection; makes the device more secure and improves the keyboard safety protection of the payment terminal grade.

Description

Keyboard safety protection device and method for payment terminal

technical field

The invention relates to the technical field of electronic equipment, in particular to a keyboard security protection device and method for a payment terminal.

Background technique

Nowadays, POS machines, password keyboards, ATM machines and other electronic equipment in the financial field use the keyboard as part of the input data information, which inputs or stores some highly sensitive data information. With the rapid development of science and technology, there are more and more application fields of financial terminal products. Therefore, the security requirements for these electronic devices are getting higher and higher. In order to prevent electronic devices from being tampered with and anti-theft, financial payment terminals must be designed with security protection. Through the cooperation of the shell and the safety protection circuit, the protection of the payment terminal is realized, and important information such as passwords are prevented from being stolen, causing serious financial losses.

The payment terminal is generally composed of several circuit boards that are installed with the mold shell, and then these boards are generally designed with electrical contacts around them. These electrical contacts are generally squeezed with conductive rubber through structural action to connect the signals together, and then After receiving the safety detection circuit, once the shell is disassembled and these points are disconnected, the safety processor will detect that the device is attacked, so that the device will automatically clear sensitive information such as keys, and the device will be locked to prevent it from continuing to operate the device .

Each safety detection electrical contact of the payment terminal in the existing technology is scattered and independent, and then connected together through structural cooperation, and sent to the safety detection circuit, without forming mutual protection between them. These electrical contacts can often be easily short-circuited by certain means, and then the casing can be disassembled without triggering safety protection, and then an information-stealing device can be hidden in the device to steal key sensitive information. For example: others can use drilling, laser, chemical solvents and other means to invade, so that these unprotected contacts are short-circuited first, and then the cover is removed. Even if other detection technologies exist at the same time, these technologies themselves are not protected by other methods. It can be disabled by certain means.

In the prior art, there is provided a "safety payment terminal cover opening data self-destruction device and method", see the Chinese patent with the publication number: and the publication date: , the method adopts the cover opening detection method based on conductive adhesive to detect security Whether the payment terminal is opened; the described open cover detection method based on conductive glue refers to setting at least one contact point on the front of the circuit board of the safety payment terminal, and setting at least one contact point on the back of the circuit board of the safety payment terminal ; The position corresponding to the contact point is coated with conductive glue on the front shell and the back shell of the safe payment terminal; the contact point includes two solder pads that are not connected to each other; time), the two pads of the contact point are conducted by the conductive glue, and the contact point is in the conduction state at this time; If the microprocessor of the secure payment terminal detects that any contact point is in the disconnected state, it is judged that the front cover or the back cover of the secure payment terminal is illegally opened, and the microprocessor in the secure payment terminal starts data self-destruction operate. The cover-opening data self-destruction device and method of the safe payment terminal are easy to implement, high in safety and low in cost. However, the contact points in this method are not protected, and the contacts are relatively vulnerable to attacks.

A "keyboard safety protection device" is also provided in the prior art. See the Chinese patent with the publication number: 102779677A and the publication date: 2012-11-14. This invention is applicable to the field of security protection of electronic equipment. The keyboard is safe The protective device includes a protective layer, metal domes, and a keyboard PCB board. The keyboard PCB board is provided with key gold fingers and a safety processor. The protective layer consists of a layer of PVDF film and the first and second silver pastes covering the surface of the PVDF film. The surface of the first and second silver pastes is provided with first and second film layers, the first and second silver pastes are electrically connected to the golden fingers of the keys, and are electrically connected to the security processor through the keyboard PCB board to form a safe detection circuit. The invention aims to solve the problem of sensitive data information of electronic circuits being stolen, and provide a keyboard safety protection device with comprehensive protection and longer service life. However, this device cannot realize the protection mechanism of realizing cross-interlocking of safety detection signals involved in this patent application document.

Contents of the invention

One of the technical problems to be solved by the present invention is to provide a keyboard security protection device for a payment terminal, which makes the payment terminal equipment more secure and improves the keyboard security protection level of the payment terminal.

One of the technical problems of the present invention is achieved in this way: a keyboard safety protection device for a payment terminal, the device includes a keyboard PCB board, a safety processor, key rubber and a dome FPC protective film; the safety processor and Keyboard PCB board connection;

There are at least two groups of cross-arranged safety network detection contacts distributed around the FPC protective film of the dome, and each group of safety network detection contacts includes at least two safety network detection input contacts and corresponding two safety network detection outputs Contacts; two safety network detection input contacts are located on one corner around the FPC protective film of the dome at the same time, and two safety network detection output contacts are located on the other corner around the FPC protective film of the dome at the same time;

The metal dome FPC protective film is provided with two layers of network wiring, and one layer of network wiring is arranged on the upper surface of the metal metal FPC protective film, and the other layer of network wiring is arranged on the lower surface of the metal metal FPC protective film; The network wiring of the layer contains two parallel lines, the starting point of the two parallel lines is two safety network detection input contacts, and the end point is two safety network detection output contacts, and the two parallel lines Wrap around the surface of the FPC protective film of the dome;

The network wiring of the first layer covers the safety network detection contact in the network wiring of another layer;

The same at least two groups of cross-arranged safety network detection contacts are distributed on the positions corresponding to the FPC protective film of the dome piece around the keyboard PCB board;

The metal dome FPC protective film is arranged on the keyboard PCB board, and two groups of cross-arranged safety network detection contacts are distributed around the dome FPC protective film and two groups of cross-arranged safety network detection contacts are distributed around the keyboard PCB board overlap each other, and be connected after being co-extruded by the button rubber and the limit column of the payment terminal shell.

The second technical problem to be solved by the present invention is to provide a keyboard security protection method for a payment terminal, which can realize a cross-interlock security protection mechanism, and through security network detection and security switch detection; making the device more secure and improving payment The keyboard security protection level of the terminal.

The second technical problem of the present invention is achieved in the following way: a keyboard security protection method for a payment terminal, the method is: at least two groups of cross-arranged safety network detection contacts are arranged around the FPC protective film of the payment terminal Each group of safety network detection contacts includes at least two safety network detection input contacts and corresponding two safety network detection output contacts; the two safety network detection input contacts are simultaneously located on one of the four sides of the FPC protective film of the dome On the corner, two safety network detection output contacts are located on the other corner around the FPC protective film of the dome at the same time;

And two layers of network wiring are arranged on the metal metal FPC protective film, and one layer of network wiring is arranged on the upper surface of the metal metal FPC protective film, and the other layer of network wiring is arranged on the lower surface of the metal metal FPC protective film; The network wiring of each layer includes two parallel lines, the starting point of the two parallel lines is two safety network detection input contacts, and the end point is two safety network detection output contacts, and the two parallel lines The wire is wound all over the surface of the FPC protective film of the dome; the network wiring of the first layer covers the safety network detection contact in the network wiring of the other layer;

Set the same at least two groups of cross-arranged safety network detection contacts at the position corresponding to the FPC protective film around the keyboard PCB board of the payment terminal;

And the metal dome FPC protective film is placed on the keyboard PCB board, so that two groups of cross-arranged safety network detection contacts are distributed around the dome FPC protective film and two groups of cross-arranged safety network detection contacts are distributed around the keyboard PCB board. The contacts overlap each other and are connected after the button rubber of the payment terminal and the limit post of the payment terminal shell are co-extruded;

Two sets of independent safety network detection signals are driven by the safety processor of the payment terminal, pass through two groups of cross-arranged safety network detection contacts around the keyboard PCB board, and then pass through the same two groups of cross-connections on the FPC protective film of the dome Arranged safety network detection contacts and corresponding two-layer network wiring, combined with the extrusion of the limit column to form a path, and then return the detection signal to the safety detection input circuit of the safety processor, so as to realize the cross interlocking of the safety detection signal To protect the safety of the keyboard.

The present invention has the following advantages: the safety processor of the present invention drives and outputs two sets of independent safety network detection signals, passes through the input and output safety network detection contacts of the cross layout of the keyboard PCB board, and then passes through the corresponding The input and output safety network detection contacts and the corresponding network wiring are arranged in the same cross layout, and then cooperate with the function of the payment terminal limit column to form a path, which is then connected to the safety detection input circuit of the safety processor to realize the cross interaction of safety detection signals. lock protection mechanism. And cooperate with the multi-channel independent safety switch detection input circuit of the safety processor to detect the electric contact of the safety switch signal to realize multi-directional cross safety protection. In this way, it is difficult for an attacker to attack the device, and it is easy to trigger the security mechanism when attacking the device, so that the security processor detects the signal of the attack, and automatically clears the key and sensitive information in the keyboard, thereby protecting the keyboard; The device is more secure, and the keypad security protection level of the payment terminal is improved.

Description of drawings

Fig. 1 is the structure schematic diagram of FPC protective film of metal pin in the present invention.

Fig. 2 is a structural schematic diagram of the network wiring on the upper surface of the metal dome FPC protective film in the present invention.

Fig. 3 is a structural schematic diagram of the network wiring on the lower surface of the FPC protective film of the metal dome in the present invention.

FIG. 4 is a schematic structural view of the key gold finger protection area on the keyboard PCB board in the present invention.

Fig. 5 is a structural schematic diagram of the relative positions of two safety network detection contacts on one corner in the present invention.

Detailed ways

Please refer to Fig. 1 to Fig. 5 shown, a kind of keyboard security protection device of payment terminal of the present invention, described device comprises keyboard PCB board, safety processor, button rubber and metal dome FPC protection film; Said safety processor Connect with the keyboard PCB board;

There are at least two groups of cross-arranged safety network detection contacts distributed around the FPC protective film of the metal dome (as shown in Figure 1, the two groups are (101,103) and (111,113); (102,104) and (112,114) are arranged cross-wise ), each group of safety network detection contacts includes at least two safety network detection input contacts and corresponding two safety network detection output contacts (as shown in Figure 1, (101,103) and (111,113) two of the group The two safety network detection input contacts are 101 and 103, and the two safety network detection output contacts are 111 and 113; (102,104) and (112,114) The two safety network detection input contacts of this group are 102 and 104, two The safety network detection output contacts are 112 and 114); the two safety network detection input contacts are located on a corner around the FPC protective film of the dome at the same time (for example: the two safety network detection input contacts are 101 and 103), The two safety network detection output contacts are located on the other corner around the FPC protective film of the dome at the same time (for example: the two safety network detection output contacts are 111 and 113); and the two safety network detection input contacts and the two The safety network detection output contacts are arranged in a cross;

As shown in Figure 2 and Figure 3, the FPC protective film of the dome is provided with two layers of network wiring, and one layer of network wiring is arranged on the upper surface of the FPC protective film of the dome, and the other layer of network wiring is arranged on the dome The lower surface of the FPC protective film; the network wiring of each layer includes two parallel lines, the starting point of the two parallel lines is two safety network detection input contacts, and the end point is two safety network detection output contacts point, and the two parallel lines wrap around the surface of the dome FPC protective film; (for example: two parallel lines (101,103) to (111,113) in one layer of network wiring; then another layer of network wiring Two parallel lines (102,104) to (112,114); the two network wirings are located on different sides of the FPC protective film of the dome.).

The network wiring of the first layer covers the safety network detection contacts in the network wiring of the other layer; (for example: the network wiring from (101, 103) to (111, 113) should cover 102, 104, 112, 114 contacts; (102,104) to (112,114) network wiring should cover four contacts 101,103,111,113). Since all input and output contacts must be on the same layer (in order to connect with the corresponding contacts on the keyboard PCB board), the network line of one layer must go to the other layer through the via, which is arranged on the side of the contact At the same time, it is also within the co-extrusion range of the button rubber and the limit post of the payment terminal shell. In this way, the top of one group of contacts on the FPC protective film formed by the safety network detection cross-interlock protection mechanism is covered by another group of protection network wiring, so that the external detection signal is going to attack these contacts It will destroy another set of protection network wiring.

The lower surface of the metal dome FPC protective film is also attached with a metal metal dome corresponding to the golden finger of the button on the keyboard PCB board (as shown in Figure 2 except for the circles of the two positions of 11' and 22') and for short Connect the metal domes corresponding to the electrical contacts of the safety switch (11' and 22' virtual frame circles).

As shown in Figure 4, the same at least two groups of cross-arranged safety network detection contacts (as shown in Figure 4, two groups of (201,203) and (211,213); (202,204) and (212,214) cross-arranged);

The metal dome FPC protective film is arranged on the keyboard PCB board, and two groups of cross-arranged safety network detection contacts are distributed around the dome FPC protective film and two groups of cross-arranged safety network detection contacts are distributed around the keyboard PCB board Overlap each other (that is, (101,103) overlaps with (201,203); (102,104) overlaps with (202,204); (112,114) overlaps with (212,214); (111,113) overlaps with (211,213)), and the overlapping safety network detection contacts pass through The button rubber and the limit post of the payment terminal shell are jointly extruded and connected; that is, there are four limit posts in total, and each limit post corresponds to the four corners around the FPC protective film of the dome; (such as (101,103 ) and (201,203) are connected after being extruded by the key rubber and the limit post of the payment terminal shell; (102,104) are connected with (202,204) after being extruded by the key rubber and the limit post of the payment terminal shell; (112,114) and (212,214) are connected after being extruded by the key rubber and the limit post of the payment terminal shell; (111,113) and (211,213) are connected after being extruded by the key rubber and the limit post of the payment terminal shell).

In the present invention, each safety network detection output contact and each safety network detection input contact on the FPC protective film of the dome are made of carbon film. These points are not easy to be welded like this, and reliable.

In the two groups of safety network detection contacts distributed around the metal dome FPC protective film, each group of safety network detection contacts is distributed diagonally, and the two safety network detection input contacts are located on the dome FPC protective film at the same time. On one of the surrounding corners, the straight line formed by the two safety network detection input contacts is at a 45-degree angle to the horizontal line (for example, the straight line formed by the two safety network detection input contacts of 101 and 103 is at a 45-degree angle to the horizontal line); The network detection output contact is located on the other corner around the FPC protective film of the dome at the same time; the straight line formed by the two safety network detection output contacts is at an angle of 45 degrees to the horizontal line (such as 111 and 113 two safety network detection input contacts The line formed makes an angle of 45 degrees to the horizontal). In this way, any of the roads has a contact on the inside and a contact on the outside. When you want to short any of the roads (101 to 111, 102 to 112, 103 to 113, 104 to 114), it will cause another road. The contacts open, which triggers the safety mechanism. The two safety network input contacts and the corresponding two output contacts in each group are arranged diagonally inside and outside.

In addition, in the present invention, at least two safety switch detection electrical contacts (as shown in FIG. 4 , safety switch detection electrical contacts 11 and 22 ) are provided in the key golden finger protection area of the keyboard PCB. The two safety switch detection electrical contacts pass through the button rubber, the metal dome under the FPC protective film corresponding to the short-circuit safety switch signal (11' and 22' in Figure 2) and the limit of the payment terminal shell. The joints are made after co-extrusion of the bits and columns. When the safety switch detects that any point of the electric contact is disconnected, the safety mechanism will be triggered, and the device will clear sensitive information and self-destruct. In this way, the safety switch detection signal is not easy to be attacked, which is equivalent to double protection (the safety network detection contact and the safety switch detection electric contact protect each other at the same time).

What needs to be explained here is: as shown in FIG. 5 , a schematic structural diagram of the relative positions of two safety network detection contacts on one corner in the present invention. That is, the two points on the abscissa and ordinate of the two safety network detection points do not overlap; the advantage of this setting is that when an attacker attacks a safety network detection point, it is bound to easily cause the same structure to be stressed. Another safety network detection point supporting the extrusion is disconnected, which will trigger the safety mechanism. (That is, if one of the two safety network detection contacts is attacked, the other contact will be disconnected due to the extrusion of the force point support)

A keyboard safety protection method for a payment terminal of the present invention, the method comprises: setting at least two groups of cross-arranged safety network detection contacts around the FPC protective film of the payment terminal, and each group of safety network detection contacts It includes at least two safety network detection input contacts and corresponding two safety network detection output contacts; the two safety network detection input contacts are located at one corner around the FPC protective film of the dome at the same time, and the two safety network detection outputs are The contacts are also located on the other corner around the FPC protective film of the dome;

And two layers of network wiring are arranged on the metal metal FPC protective film, and one layer of network wiring is arranged on the upper surface of the metal metal FPC protective film, and the other layer of network wiring is arranged on the lower surface of the metal metal FPC protective film; The network wiring of each layer includes two parallel lines, the starting point of the two parallel lines is two safety network detection input contacts, and the end point is two safety network detection output contacts, and the two parallel lines The wire is wound all over the surface of the FPC protective film of the metal dome; the network wiring of the first layer covers the safety network detection contacts in the network wiring of the other layer; in this way, the safety network detects on the FPC protective film formed by the cross interlocking protection mechanism The top of the contacts on one of the groups is covered by another group of protective network wiring, so that the external detection signal will attack these contacts and will destroy the other group of protective network wiring.

Set the same at least two groups of cross-arranged safety network detection contacts at the position corresponding to the FPC protective film around the keyboard PCB board of the payment terminal;

And the metal dome FPC protective film is placed on the keyboard PCB board, so that two groups of cross-arranged safety network detection contacts are distributed around the dome FPC protective film and two groups of cross-arranged safety network detection contacts are distributed around the keyboard PCB board. The contacts overlap each other and are connected by pressing together the button rubber of the payment terminal and the limit post of the payment terminal shell; any safety network disconnection or short circuit with other safety networks on the FPC protective film of the dome will trigger Security mechanism, the device clears sensitive information and self-destructs.

Two sets of independent safety network detection signals are driven by the safety processor of the payment terminal, pass through two groups of cross-arranged safety network detection contacts around the keyboard PCB board, and then pass through the same two groups of cross-connections on the FPC protective film of the dome Arranged safety network detection contacts and corresponding two-layer network wiring, combined with the extrusion of the limit column to form a path, and then return the detection signal to the safety detection input circuit of the safety processor, so as to realize the cross interlocking of the safety detection signal To protect the safety of the keyboard. In this way, when an attacker attacks any set of safety network detection contacts, the safety processor will detect the attacked signal, and automatically clear the keys and sensitive information in the keyboard, thereby protecting the keyboard.

Wherein, each safety network detection output contact and each safety network detection input contact on the FPC protective film of the dome are made of carbon film. These points are not easy to be welded like this, and reliable.

In the two groups of safety network detection contacts distributed around the metal dome FPC protective film, each group of safety network detection contacts is distributed diagonally, and the two safety network detection input contacts are located on the dome FPC protective film at the same time. On one corner of the perimeter, the straight line formed by the two safety network detection input contacts is at an angle of 45 degrees to the horizontal line; the two safety network detection output contacts are simultaneously located on the other corner around the FPC protective film of the dome; the two safety network detection The line formed by the network detection output contacts is at an angle of 45 degrees to the horizontal line. In this way, any one of them has a contact on the inside and one contact on the outside. When trying to short any one of them, it will cause the other contact to be disconnected, which will trigger the safety mechanism. The two safety network input contacts and the corresponding two output contacts in each group are arranged diagonally inside and outside (if the input contact of one network is located outside a corner, then the corresponding output contact should be located at the opposite corner inside position).

In addition, in the present invention, at least two safety switch detection electrical contacts are arranged in the key golden finger protection area of the keyboard PCB. The straight line formed by the two safety switch detection electrical contacts forms an angle of 45 degrees with the horizontal line. These two safety detection switches are squeezed and connected by the corresponding metal dome under the FPC protective film of the dome and the mold. If the structure is broken, the safety mechanism will be triggered. The two safety switch detection electrical contacts are connected by pressing together the button rubber, the corresponding metal dome under the dome FPC protective film for short-circuiting the safety switch signal, and the limit post of the payment terminal shell. When the safety switch detects that any point of the electric contact is disconnected, the safety mechanism will be triggered, and the device will clear sensitive information and self-destruct. In this way, the safety switch detection signal is not easy to be attacked, which is equivalent to double protection (the safety network detection contact and the safety switch detection electric contact protect each other at the same time).

In addition, in the invention, since the same structural point presses two safety contacts at the same time, when an attacker attacks the safety network signal of one contact, it is easy to trigger the safety network signal of the other contact.

The detection electric contacts of the safety switch are protected by the detection signal of the safety network, forming a mutual protection effect. Any one of the safety electrical contacts triggers safety due to disconnection, which will cause the device to self-destruct.

The present invention will be further described below in conjunction with a specific embodiment:

Please refer to Fig. 1 to Fig. 5, there are multiple safety switch detection signals in the payment terminal of the present invention, and each safety switch detection signal is formed by connecting several safety switch detection electric contacts in series, and these safety switch detection electric contacts It is connected through the interaction and extrusion of the structure (that is, the limit post) and the conductive rubber or metal dome, and each safety switch signal has a key electrical contact point distributed in the gold finger protection area of the button (as shown in Figure 4 11, 22). The key gold finger protection area of the keyboard PCB board is covered with a dome FPC protective film (the design schematic diagram of the protective film is shown in Figure 1). There are two sets of cross-arranged safety network detection contacts distributed around the gold finger protection area of the key (two sets of corresponding signals are (101,103) and (111,113); (102,104) and (112,114) are arranged cross-wise). The signals of these two groups of contacts realize the corresponding input and output contact connections by covering the corresponding input and output contacts with the same cross-arranged layout rules and corresponding network wiring on the FPC protective film above them. The two groups of networks on the FPC protective film of the dome are wired in layers, and each layer is composed of a pair of lines with small spacing and thin line width running parallel lines (101, 103) to (111, 113) and (102, 104) to (112, 114); The safety network of each layer is wrapped around one layer, and the network wiring of one layer must cover the contacts of the other layer. The network lines from (101,103) to (111,113) should cover the four contacts of 102,104,112,114; the network lines from (102,104) to (112,114) should cover the four contacts of 101,103,111,113 contacts. Since all the input and output contacts on the FPC protective film of the dome must be on the same layer (in order to connect with the corresponding contacts on the keyboard PCB board), the network lines of one layer must go to the other layer through the via hole. The holes are arranged on the edge of the contacts, and are also within the co-extrusion range of the button rubber and the limit post of the payment terminal shell. Realize mutual protection of two sets of signals. The safety network detection signal contacts distributed on the FPC protective film of the dome, where the two adjacent contacts at each corner (such as a pair (101, 103) in Figure 1) and the keyboard PCB board The two adjacent contacts (a pair of (201, 203) in Figure 4) corresponding to the gold finger protection zone of the button cooperate to squeeze and connect through the same button rubber and the cylindrical limit post of the shell (also It is a limit column that withstands two safety detection contacts at the same time). In addition, the other three pairs of safety network detection signal contacts on the FPC protective film of the metal dome and the signal contacts of the key gold finger protection area on the corresponding keyboard PCB board are also processed in the same way through structural cooperation (in Figure 1 A pair of (102,104)) corresponds to (a pair of (202,204) in Figure 4); (a pair of (112,114) in Figure 1) corresponds to (a pair of (212,214) in Figure 4); (a pair (111, 113) in Figure 1) corresponds to (a pair (211, 213) in Figure 4). If the housing is released and the points are disconnected, the safety mechanism is triggered. If the attacker uses some means to try to lift the FPC protective film covering the gold finger protection area of the keyboard, short-circuit 101 and 111 contacts, or 102 and 112 contacts, or 103 and 113 contacts, or 104 and 114 contacts Click any of them. It will cause another group of contacts to trigger, because they are arranged crosswise inside and outside, and a limit column withstands two safety detection contacts at the same time, which has a mutual protection effect. At the same time, the safety network detection contact on the FPC protective film of the dome adopts the carbon film design method, and the design size is small enough to not be easily attacked. In addition, one of the key electrical contacts of the safety switch detection signal of each channel is respectively arranged in the gold finger protection area of the button (11, 22 in Figure 4), and the safety switch detection electrical contacts on the keyboard PCB board pass through the pot The corresponding dome on the FPC protective film of the chip and the shell structure of the payment terminal cooperate to withstand the connection, so that they are connected in series to their respective safety switch detection circuits. If you want to open the cover, you must first short-circuit the security devices under the FPC protective film. The switch detects the electrical contact point. This mechanism is safer than the original safety detection switch electrical contact point that is not protected by the FPC protective film.

Two sets of independent safety network detection signals are driven by the safety processor of the payment terminal, pass through two groups of cross-arranged safety network detection contacts around the keyboard PCB board, and then pass through the same two groups of cross-connections on the FPC protective film of the dome Arranged safety network detection contacts and corresponding two-layer network wiring, combined with the extrusion of the limit column to form a path, and then return the detection signal to the safety detection input circuit of the safety processor, so as to realize the cross interlocking of the safety detection signal To protect the safety of the keyboard. In this way, when an attacker attacks any set of safety network detection contacts, the safety processor will detect the attacked signal, and automatically clear the keys and sensitive information in the keyboard, thereby protecting the keyboard.

What needs to be explained here is: as shown in FIG. 5 , a schematic structural diagram of the relative positions of two safety network detection contacts on one corner in the present invention. That is, the two points on the abscissa and ordinate of the two safety network detection points do not overlap; the advantage of this setting is that when an attacker attacks a safety network detection point, it is bound to easily cause the same structure to be stressed. Another safety network detection point supporting the extrusion is disconnected, which will trigger the safety mechanism. (That is, if one of the two safety network detection contacts is attacked, the other contact will be disconnected due to the extrusion of the force point support)

The above descriptions are only preferred embodiments of the present invention, and all equivalent changes and modifications made according to the scope of the patent application of the present invention shall fall within the scope of the present invention.

Claims (11)

1. A keyboard safety protection device for a payment terminal, said device comprising a keyboard PCB board, a safety processor, button rubber and metal pin FPC protective film; it is characterized in that: said safety processor is connected with a keyboard PCB board; There are at least two groups of cross-arranged safety network detection contacts distributed around the FPC protective film of the dome, and each group of safety network detection contacts includes at least two safety network detection input contacts and corresponding two safety network detection outputs Contacts; two safety network detection input contacts are located on one corner around the FPC protective film of the dome at the same time, and two safety network detection output contacts are located on the other corner around the FPC protective film of the dome at the same time; The metal dome FPC protective film is provided with two layers of network wiring, and one layer of network wiring is arranged on the upper surface of the metal metal FPC protective film, and the other layer of network wiring is arranged on the lower surface of the metal metal FPC protective film; The network wiring of the layer contains two parallel lines, the starting point of the two parallel lines is two safety network detection input contacts, and the end point is two safety network detection output contacts, and the two parallel lines Wrap around the surface of the FPC protective film of the dome; The network wiring of the first layer covers the safety network detection contact in the network wiring of another layer; The same at least two groups of cross-arranged safety network detection contacts are distributed on the positions corresponding to the FPC protective film of the dome piece around the keyboard PCB board; The metal dome FPC protective film is arranged on the keyboard PCB board, and two groups of cross-arranged safety network detection contacts are distributed around the dome FPC protective film and two groups of cross-arranged safety network detection contacts are distributed around the keyboard PCB board overlap each other, and be connected after co-extruding the button rubber and the limit post of the payment terminal shell; In the two groups of safety network detection contacts distributed around the metal dome FPC protective film, each group of safety network detection contacts is distributed diagonally, and the two safety network detection input contacts are located on the dome FPC protective film at the same time. On one corner of the perimeter, the straight line formed by the two safety network detection input contacts is at an angle of 45 degrees to the horizontal line; the two safety network detection output contacts are simultaneously located on the other corner around the FPC protective film of the dome; the two safety network detection The straight line formed by the network detection output contacts is at an angle of 45 degrees to the horizontal line; the two safety network input contacts and the corresponding two output contacts in each group are arranged diagonally inside and outside. 2 . The keyboard safety protection device of a payment terminal according to claim 1 , wherein the safety network detection output contacts and the safety network detection input contacts on the FPC protective film are made of carbon film. 3 . 3. The keyboard safety protection device of the payment terminal according to claim 1, characterized in that: at least two safety switch detection electrical contacts are arranged in the gold finger protection area of the key on the keyboard PCB. 4. The keyboard safety protection device of the payment terminal according to claim 3, characterized in that: said two safety switch detection electric contacts pass through the button rubber, and the corresponding ones under the FPC protective film of the dome are used to short-circuit the safety switch signal The dome and the limit post of the payment terminal shell are jointly extruded and connected. 5. A keyboard safety protection method for a payment terminal, characterized in that: the method is: at least two groups of cross-arranged safety network detection contacts are set around the FPC protective film of the payment terminal, and the safety network of each group The detection contacts include at least two safety network detection input contacts and corresponding two safety network detection output contacts; the two safety network detection input contacts are located on one corner around the FPC protective film of the dome at the same time, and the two safety network detection The network detection output contact is also located on the other corner around the FPC protective film of the dome; And two layers of network wiring are arranged on the metal metal FPC protective film, and one layer of network wiring is arranged on the upper surface of the metal metal FPC protective film, and the other layer of network wiring is arranged on the lower surface of the metal metal FPC protective film; The network wiring of each layer includes two parallel lines, the starting point of the two parallel lines is two safety network detection input contacts, and the end point is two safety network detection output contacts, and the two parallel lines The wire is wound all over the surface of the FPC protective film of the dome; the network wiring of the first layer covers the safety network detection contact in the network wiring of the other layer; Set the same at least two groups of cross-arranged safety network detection contacts at the position corresponding to the FPC protective film around the keyboard PCB board of the payment terminal; And the metal dome FPC protective film is placed on the keyboard PCB board, so that two groups of cross-arranged safety network detection contacts are distributed around the dome FPC protective film and two groups of cross-arranged safety network detection contacts are distributed around the keyboard PCB board. The contacts overlap each other and are connected after the button rubber of the payment terminal and the limit post of the payment terminal shell are co-extruded; Two sets of independent safety network detection signals are driven by the safety processor of the payment terminal, pass through two groups of cross-arranged safety network detection contacts around the keyboard PCB board, and then pass through the same two groups of cross-connections on the FPC protective film of the dome Arranged safety network detection contacts and corresponding two-layer network wiring, combined with the extrusion of the limit column to form a path, and then return the detection signal to the safety detection input circuit of the safety processor, so as to realize the cross interlocking of the safety detection signal To protect the safety of the keyboard; In the two groups of safety network detection contacts distributed around the metal dome FPC protective film, each group of safety network detection contacts is distributed diagonally, and the two safety network detection input contacts are located on the dome FPC protective film at the same time. On one corner of the perimeter, the straight line formed by the two safety network detection input contacts is at an angle of 45 degrees to the horizontal line; the two safety network detection output contacts are simultaneously located on the other corner around the FPC protective film of the dome; the two safety network detection The straight line formed by the network detection output contacts is at an angle of 45 degrees to the horizontal line; the two safety network input contacts and the corresponding two output contacts in each group are arranged diagonally inside and outside. 6. The keyboard safety protection method of payment terminal according to claim 5, characterized in that: each safety network detection output contact and each safety network detection input contact on the said dome FPC protective film are made of carbon film constituted. 7. The keyboard security protection method of the payment terminal according to claim 5, characterized in that: at least two safety switch detection electrical contacts are set in the key golden finger protection area of the keyboard PCB. 8. The keyboard safety protection method of the payment terminal according to claim 7, characterized in that: said two safety switch detection electric contacts pass through the button rubber, and the corresponding ones under the FPC protective film of the dome are used to short-circuit the safety switch signal The dome and the limit post of the payment terminal shell are jointly extruded and connected. 9. The keyboard security protection method of a payment terminal according to claim 5, characterized in that: the same structural point simultaneously squeezes two safety network detection contacts, and it is easy for an attacker to attack the safety network signal of one of the contacts. Trigger the safety network signal of another contact; in the surrounding two groups of cross-arranged safety network detection contacts, short-circuiting any two safety network detection contacts arranged inside and outside the cross will cause another group of contacts to trigger, and one limit The position column withstands two safety detection contacts at the same time, and has the function of mutual protection. 10. The keyboard safety protection method of payment terminal according to claim 7, characterized in that: the safety switch detection electric contact is protected by the safety network detection signal, forming the effect of mutual protection; any one of the safety electric contact is disconnected Triggering the safety will cause the device to self-destruct. 11. The keyboard safety protection method of payment terminal according to claim 5, characterized in that: when an assailant attacks any group of safety network detection contacts, the safety processor will detect the attacked signal, and automatically Protect the keyboard by clearing keys and sensitive information from the keyboard.