CN104201167B - A kind of welding pad structure and display device - Google Patents

Abstract

The invention discloses a welding pad structure and a display device. The welding pad structure includes a first welding pad unit and a second welding pad unit which are electrically connected by pressing. Since the first welding pad unit is divided into at least two The welding area is equivalent to dividing the pad structure into at least two welding areas, and a detection unit is provided for each welding area. Through the detection pad and the comparison circuit in the detection unit, it can be estimated that the corresponding welding area The contact resistance between the first welding pad and the second welding pad can adjust the current of different welding areas according to the estimation results, thereby improving the uneven contact resistance caused by the different welding areas of the welding pad structure. To influence the signal transmission, and then when the above pad structure is applied to a display device, it can improve the defective display products caused by the non-uniform contact resistance of different welding areas of the pad structure.

Description

A pad structure and display device

technical field

The invention relates to the technical field of semiconductors, in particular to a pad structure and a display device.

Background technique

With the development of the electronics and communication industries, the development of light-emitting diodes (Light Emitting Diode, LED), organic light-emitting diodes (Organic Light Emitting Diode, OLED), plasma displays (Plasma DisplayPanel, PDP) and liquid crystal displays (Liquid Crystal Display, LCD) The demand for flat-panel display devices such as LEDs is increasing day by day. The development trend of flat panel display devices is light, thin, short, and small. Packaging technology with high density, small volume, and high installation freedom is required to meet the above requirements. Therefore, Chip on Glass (COG) packaging Technology came into being.

COG is to fix the driver chip on the display panel, use the display panel as the carrier for packaging the driver chip, and bond the driver chip with the circuit of the display panel. In the existing COG structure, as shown in Figure 1, a part of the welding pads of the driver chip 1 and a part of the welding pads on the non-display area of the display panel 4 are electrically connected to each other as the signal input terminal 2 of the driver chip 1, The other part of the welding pad of the driver chip 1 is electrically connected with another part of the welding pad of the non-display area of the display panel 4 as the signal output terminal 3 of the driver chip 1, wherein the signal input terminal 2 is used to input to the driver chip 1 Signal, the signal output terminal 3 is used to output the signal input to the driving chip 1 to the display panel 4 after being processed by the driving core 1 .

In the above-mentioned COG structure, as shown in FIG. 2a and FIG. 2b, the bonding pad 11 on the driver chip 1 is bonded to the bonding pad on the display panel 4 by means of anisotropic conductive film (Anisotropic Conductive Film, ACF). The pads 41 are electrically connected, so that the driving chip 1 transmits driving signals to each signal line in the display panel 4 . Here, the two sets of pads that are electrically connected by crimping are referred to as a pad structure, for example, the signal input end and the signal output end are both a pad structure, where Figure 2a shows the pad structure before crimping, Figure 2b shows the pad structure after crimping.

Based on some problems existing in the current COG process, such as in the above-mentioned COG structure, the flatness of the pad structure is not good, the ACF is abnormal, and the two pads that are electrically connected have alignment offsets, etc., which will cause the pad structure to be damaged. The contact resistance of different welding areas is uneven, which affects the transmission of signals, resulting in the hidden danger of abnormal display in the subsequent use of display products, and the contact resistance of the pad structure will also change with the accumulation of time, temperature and humidity.

Therefore, how to improve the defective display products caused by the non-uniform contact resistance of different welding regions of the pad structure is a technical problem urgently needed to be solved by those skilled in the art.

Contents of the invention

In view of this, an embodiment of the present invention provides a pad structure and a display device for improving display product defects caused by non-uniform contact resistance of different soldering regions of the pad structure.

Therefore, an embodiment of the present invention provides a pad structure, including a first pad unit and a second pad unit electrically connected by crimping, wherein the first pad unit has a plurality of pads arranged side by side The first welding pad, the second welding pad unit has a plurality of second welding pads arranged side by side, and each of the second welding pads is electrically connected to the corresponding first welding pad; A welding pad unit is divided into at least two welding areas, and each welding pad area is provided with multiple sets of electrically connected second welding pads and first welding pads; A detection unit for the contact resistance between the first welding pad and the second welding pad in the welding area; wherein the detection unit includes:

Two first detection pads located in the welding area, arranged side by side with the first pads, and spaced apart from each other between two adjacent first pads, the first The structure of the detection pad is the same as that of the first pad;

A second detection pad located on the second pad unit and located in a region corresponding to the first detection pad, the second detection pad connected in series with the two first detection pads ;as well as

A comparison circuit electrically connected to the two first detection pads in series, the comparison circuit is used to determine the resistance value range of the two first detection pads in series.

Preferably, for the convenience of implementation, in the above pad structure provided by the embodiment of the present invention, the structure of the second detection pad is a planar structure.

Preferably, in order to make the detection result more accurate, in the above pad structure provided by the embodiment of the present invention, the surface area of the second detection pad is greater than twice the surface area of the second pad.

Preferably, for the convenience of implementation, in the above pad structure provided by the embodiment of the present invention, the comparison circuit is a multi-level comparison circuit; wherein,

The first-level comparison subcircuit is used to compare the resistance values of the two first detection pads connected in series with the reference resistance corresponding to the first-level comparison subcircuit, and if it is less than the reference resistance, then Outputting a first output signal; if it is greater than the reference resistance, then outputting a second output signal;

Except for the comparison subcircuit of the first level, the comparison subcircuits of the other levels are used to, after receiving the second output signal sent by the comparison subcircuit of the upper level, compare the resistance values of the two first detection pads connected in series Comparing with the reference resistance corresponding to the comparison sub-circuit of this stage, if it is smaller than the reference resistance, then output the first output signal; if it is greater than the reference resistance, then output the second output signal;

Except for the comparison sub-circuit of the last level, the comparison sub-circuits of other levels are also used to output the second output signal to the comparison sub-circuit of the next level when the comparison sub-circuit of this level outputs the second output signal;

Wherein, the resistance value of the reference resistors corresponding to the comparison sub-circuits of each stage increases with the increase of the stages.

Preferably, in order to simplify the structure of the comparison circuit, in the above pad structure provided by the embodiment of the present invention, the comparison circuit is a two-stage comparison circuit.

Specifically, in a possible implementation manner, in the above pad structure provided by the embodiment of the present invention, the first stage comparison subcircuit; specifically includes: a first reference voltage terminal, a second reference voltage terminal, a positive power supply, negative power supply, first reference resistor, first voltage comparator; where,

The positive phase input terminal of the first voltage comparator is connected to the first terminal of the first reference resistor, the negative phase input terminal of the first voltage comparator is connected to the first reference voltage terminal, and the first voltage The first power supply input terminal of the comparator is connected to the positive power supply, the second power supply input terminal of the first voltage comparator is connected to the negative power supply, and the output terminals of the first voltage comparator are respectively connected to the first output signal terminal and the second power supply terminal. The secondary comparator circuit is connected;

The two first detection pads connected in series are connected between the second reference voltage terminal and the first terminal of the first reference resistor, and the second terminal of the first reference resistor is grounded;

The voltage at the second reference voltage terminal is equal to twice the voltage at the first reference voltage terminal.

Further, in a possible implementation manner, in the above pad structure provided by the embodiment of the present invention, the second-level comparison subcircuit specifically includes: a second reference resistor and a second voltage comparator; wherein,

The positive-phase input terminal of the second voltage comparator is respectively connected to the first terminal of the second reference resistor and the first terminal of the first reference resistor, and the negative-phase input terminal of the second voltage comparator is connected to the first terminal of the first reference resistor. The first reference voltage terminal is connected, the first power input terminal of the second voltage comparator is connected to the output terminal of the first voltage comparator, and the second power input terminal of the second voltage comparator is connected to the The negative power supply is connected, and the output terminal of the second voltage comparator is connected with the second output signal terminal.

Preferably, in the above welding pad structure provided by the embodiment of the present invention, for each of the welding areas, a current regulating circuit is further included;

The current regulating circuit is used for regulating the current of the welding area according to the output result of the comparing circuit.

Correspondingly, an embodiment of the present invention also provides a display device, including at least one of the above-mentioned pad structures as provided in the embodiments of the present invention.

Further, in the above display device provided by the embodiment of the present invention, the display device further includes a display panel and a driver chip, and the driver chip inputs signals to the display panel through the pad structure; wherein,

The first pad unit of the pad structure is located on the display panel, and the second pad unit of the pad structure is located on the driving chip; or

The first pad unit of the pad structure is located on the driving chip, and the second pad unit of the pad structure is located on the display panel.

In the above-mentioned pad structure and display device provided by the embodiments of the present invention, the pad structure includes a first pad unit and a second pad unit that are electrically connected by crimping. Since the first pad unit is divided into at least two welding area, which is equivalent to dividing the pad structure into at least two welding areas, and a detection unit is provided for each welding area, and the corresponding welding area can be estimated through the detection pad and comparison circuit in the detection unit The contact resistance between the first welding pad and the second welding pad, so that the current in different welding areas can be adjusted according to the estimation results, so that the problem caused by the uneven contact resistance of different welding areas of the welding pad structure can be improved. The resulting impact on signal transmission, and then when the above pad structure is applied to a display device, can improve the problem of defective display products caused by non-uniform contact resistance of different welding areas of the pad structure.

Description of drawings

FIG. 1 is a schematic structural diagram of an existing COG structure;

Fig. 2a is a structural schematic diagram of the existing pad structure before crimping;

Fig. 2b is a structural schematic diagram of the existing pad structure after crimping;

FIG. 3 is a schematic structural diagram of a pad structure provided by an embodiment of the present invention;

FIG. 4 is a schematic structural diagram of a multi-level comparison circuit provided by an embodiment of the present invention;

FIG. 5 is a schematic structural diagram of a secondary comparison circuit provided by an embodiment of the present invention.

detailed description

The specific implementation manners of the pad structure and the display device provided by the embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

A pad structure provided by an embodiment of the present invention, as shown in FIG. 3 , includes a first pad unit 100 and a second pad unit 200 that are electrically connected by crimping. A plurality of first welding pads 101 arranged side by side, the second welding pad unit has a plurality of second welding pads 201 arranged side by side, and each second welding pad 201 is electrically connected to the corresponding first welding pad 101; The first welding pad unit 100 is divided into at least two welding areas (the area surrounded by each dotted line frame in FIG. 3 is a welding area), and each welding pad area is provided with multiple sets of electrically connected second welding pads 201 and the first welding pad 101; for each welding area, a detection unit for estimating the contact resistance between the first welding pad 101 and the second welding pad 201 in the welding area is provided; wherein, the detection unit includes :

Two first detection pads 301 located in the welding area, arranged side by side with the first pads 101, and spaced apart from each other between two adjacent first pads 101, the first detection pads 301 The structure is the same as that of the first welding pad 101;

The second detection pad 302 located on the second pad unit 200 and located in the area corresponding to the first detection pad 301, the second detection pad 302 connects two first detection pads 301 in series; and

The comparison circuit 303 is electrically connected to the two first detection pads 301 in series, and the comparison circuit 303 is used to determine the resistance value range of the two first detection pads 301 in series.

The above pad structure provided by the embodiment of the present invention includes a first pad unit and a second pad unit that are electrically connected by crimping. Since the first pad unit is divided into at least two soldering areas, it is equivalent to The welding pad structure is divided into at least two welding areas, and a detection unit is provided for each welding area. Through the detection welding pad in the detection unit and the comparison circuit, it is possible to estimate the first welding pad in the corresponding welding area. The contact resistance between the second welding pads, so that the currents of different welding areas can be adjusted according to the estimation results, so that the signal transmission caused by the uneven contact resistance of different welding areas of the welding pad structure can be improved. Influence, and then when the above pad structure is applied to a display device, it can improve the problem of defective display products caused by the non-uniform contact resistance of different welding areas of the pad structure.

It should be noted that, in the above-mentioned pad structure provided by the embodiment of the present invention, the first pad unit is divided into at least two welding areas. In specific implementation, it can be based on the actual situation, such as the overall size of the pad structure, and The accuracy of the detection, etc., determine how many welding areas the first pad unit is specifically divided into. Moreover, the size of each welding area may be the same or different, depending on the actual situation.

Preferably, during specific implementation, in the above-mentioned pad structure provided by the embodiment of the present invention, the first pad unit is divided into three side-by-side welding areas, and each welding area has the same size.

Preferably, in the above pad structure provided by the embodiment of the present invention, as shown in FIG. 3 , the structure of the second detection pad 302 is a planar structure.

Preferably, in order to make the detection result more accurate, in the above pad structure provided by the embodiment of the present invention, the surface area of the second detection pad is greater than twice the surface area of the second pad.

Further, in the above-mentioned welding pad structure provided by the embodiment of the present invention, the width of the second detection welding pad in the direction along which the second welding pads are arranged side by side is equal to the width of the two second welding pads along this direction plus The width of the gap between the two first detection pads; the length of the second detection pads in the direction perpendicular to the arrangement of the second pads is equal to the length of the second pads in this direction.

Preferably, for the convenience of implementation, in the above pad structure provided by the embodiment of the present invention, as shown in FIG. 4 , the comparison circuit 303 is a multi-level comparison circuit; wherein,

The first-level comparison sub-circuit 303_1 is used to compare the resistance values of the two first detection pads 301 connected in series with the reference resistance corresponding to the first-level comparison sub-circuit 303_1, and if it is less than the reference resistance, output the first output signal; if it is greater than the reference resistance, then output the second output signal;

Except for the comparison sub-circuit 303_1 of the first level, the comparison sub-circuits 303_n of the other levels (n=2, 3, 4...N, wherein N is the number of stages of the multi-level comparison circuit) are used to receive the upper level comparison sub-circuit After the second output signal sent by the circuit 303_n-1 (n=2, 3, 4...N, where N is the number of stages of the multi-level comparison circuit), the resistance values of the two first detection pads connected in series and Comparing with the reference resistance corresponding to the comparison sub-circuit of this stage, if it is smaller than the reference resistance, then output the first output signal; if it is greater than the reference resistance, then output the second output signal;

Except the comparison sub-circuit 303_N of the last level, the comparison sub-circuits 303_n of all levels (n=1, 2, 3...N-1, wherein N is the number of stages of the multi-level comparison circuit) are also used when the comparison sub-circuit of this level When the circuit outputs the second output signal, output the second output signal to the next-level comparison sub-circuit 303_n+1 (n=1, 2, 3...N-1, wherein N is the number of stages of the multi-level comparison circuit);

Wherein, the resistance value of the reference resistors corresponding to the comparison sub-circuits of each stage increases with the increase of the stages.

Specifically, in the above pad structure provided by the embodiment of the present invention, the more stages there are in the comparison circuit, the more accurate the resistance value range of the two first detection pads connected in series is, but the relative comparison circuit The more complex the structure, the higher the cost. Therefore, in actual implementation, the number of stages of the comparison circuit is determined according to the actual situation.

Preferably, in the above pad structure provided by the embodiment of the present invention, the comparison circuit is selected as a secondary comparison circuit.

Specifically, in a possible implementation manner, in the above pad structure provided by the embodiment of the present invention, as shown in FIG. 5 , the first stage comparison sub-circuit 303_1; Two reference voltage terminals Vref2, positive power supply VDD, negative power supply -VDD, a first reference resistor 011, and a first voltage comparator 012; wherein,

The positive phase input terminal of the first voltage comparator 012 is connected to the first terminal of the first reference resistor 011, the negative phase input terminal of the first voltage comparator 012 is connected to the first reference voltage terminal Vref1, and the first voltage comparator 012 The first power supply input terminal is connected to the positive power supply VDD, the second power supply input terminal of the first voltage comparator 012 is connected to the negative power supply -VDD, and the output terminals of the first voltage comparator 012 are respectively connected to the first output signal terminal Output1 and the second The stage comparison sub-circuit 303_2 is connected;

The two first detection pads 301 connected in series are connected between the second reference voltage terminal Vref2 and the first end of the first reference resistor 011, and the second end of the first reference resistor 011 is grounded;

The voltage of the second reference voltage terminal Vref2 is equal to twice the voltage of the first reference voltage terminal Vref1 .

The above is just an example to illustrate the specific structure of the first-level comparison sub-circuit in the second-level comparison circuit. In actual implementation, the specific structure of the first-level comparison sub-circuit is not limited to the above-mentioned structure provided by the embodiment of the present invention, and can also be a Other structures known by a skilled person are not limited here.

Specifically, when the first-level comparison subcircuit in the above-mentioned two-level comparison circuit provided by the embodiment of the present invention adopts the above-mentioned first reference resistor and the first voltage comparator as specific structures, its working principle is as follows: Assuming that the first reference signal The voltage at the terminal is V ₀ , the voltage at the second reference signal terminal is 2V ₀ , the resistance of the first reference resistor is R ₁ , and the resistance of the two first detection pads connected in series is R. The detection pad is connected between the second reference voltage terminal and the first end of the first reference resistor, and the second end of the first reference resistor is grounded; therefore, if the resistance R of the two first detection pads connected in series is less than R ₁ , the voltage at the first terminal of the first reference resistor is greater than V ₀ , at this time, the voltage at the positive-phase input terminal of the first voltage comparator is lower than the voltage at the negative-phase input terminal, and the output terminal of the first voltage comparator is The first output signal terminal outputs the first output signal, that is, the low potential signal -U ₀ , indicating that the resistance of the two first detection pads in series is relatively small; if the resistance R of the two first detection pads in series is greater than R ₁ , the voltage at the first terminal of the first reference resistor is less than V ₀ , at this time, the voltage at the positive phase input terminal of the first voltage comparator is greater than the voltage at the negative phase input terminal, and the output terminal of the first voltage comparator is sent to the first voltage comparator. The first output signal terminal outputs the second output signal, that is, the high potential signal U ₀ , and outputs the second output signal to the second-level comparison sub-circuit, indicating that the resistance of the two first detection pads in series is relatively large, and it needs to be controlled by the second Level comparison sub-circuit to determine what range is large.

Further, in a possible implementation manner, in the above pad structure provided by the embodiment of the present invention, as shown in FIG. Comparator 022; wherein,

The positive phase input terminal of the second voltage comparator 022 is connected with the first terminal of the second reference resistor 021 and the first terminal of the first reference resistor 011 respectively, and the negative phase input terminal of the second voltage comparator 022 is connected with the first reference voltage Terminal Vref1 is connected, the first power supply input terminal of the second voltage comparator 022 is connected with the output terminal of the first voltage comparator 303_1, the second power supply input terminal of the second voltage comparator 022 is connected with the negative power supply -VDD, and the second voltage The output terminal of the comparator 022 is connected to the second output signal terminal Output2.

The above is just an example to illustrate the specific structure of the second-level comparison sub-circuit in the second-level comparison circuit. Other structures known by a skilled person are not limited here.

Specifically, when the second-stage comparison subcircuit in the above-mentioned two-stage comparison circuit provided by the embodiment of the present invention adopts the above-mentioned second reference resistor and the second voltage comparator as a specific structure, its working principle is as follows: assuming that the second reference resistor The resistance value is R ₂ , and R ₂ >R ₁ , if the second comparison sub-circuit receives the second output signal from the first comparison sub-circuit, since the two first detection pads in series are connected to the second Between the two reference voltage terminals and the first terminal of the second reference resistor, and the second terminal of the second reference resistor is grounded; therefore, if the resistance R of the two first detection pads connected in series is less than R ₂ , the second reference The voltage at the first terminal of the resistor is greater than V ₀ , at this time, the voltage at the positive-phase input terminal of the second voltage comparator is lower than the voltage at the negative-phase input terminal, and the output terminal of the second voltage comparator outputs the first signal to the second output signal terminal. An output signal is the low potential signal -U ₀ , indicating that the resistance R of the two first detection pads in series is greater than R ₁ and smaller than R ₂ ; if the resistance of the two first detection pads in series is greater than R ₂ , Then the voltage at the first end of the second reference resistor is less than V ₀ , at this time, the voltage at the positive input end of the second voltage comparator is greater than the voltage at the negative input end, and the output end of the second voltage comparator is output to the second The signal terminal outputs the second output signal, that is, the high potential signal U ₀ , indicating that the resistance R of the two first detection pads connected in series is larger than R ₂ , and if it is necessary to determine the range, it is necessary to increase the number of stages of the comparison circuit up.

Specifically, taking the second-level comparison circuit of the first-level comparison subcircuit and the second-level comparison subcircuit with specific structures provided in the above-mentioned embodiment as an example, the output results are shown in Table 1. According to Table 1, it can be determined that the two The range of the resistance of the first detection pad. Among them, Output1 in Table 1 represents the first output signal terminal of the secondary comparison circuit, Output2 represents the second output signal terminal of the secondary comparison circuit, R represents the resistance value of the two _first detection pads connected in series, and R1 represents The resistance value of the first reference resistor, R ₂ represents the resistance value of the second reference resistor, U ₀ represents the second output signal, which is a high potential signal, and -U ₀ represents the first output signal, which is a low potential signal.

Table 1

The above specific embodiments are only illustrated with a two-level comparison circuit. If it is a three-level or more comparison circuit, it can be realized by adding a reference resistor and a voltage comparator on the basis of the above-mentioned two-level comparison circuit, and each Adding a first-level comparison subcircuit requires adding a reference resistor and a voltage comparator. Specifically, the connection between the added reference resistor and the voltage comparator can be compared with the second reference resistor and the second voltage in the second-level comparison subcircuit. The connection of the device will not be repeated here.

Further, in the above-mentioned pad structure provided by the embodiment of the present invention, in each comparison circuit, the resistance value of the reference resistor corresponding to each level of comparison sub-circuit is preset, and the specific setting size can be determined according to the actual situation. Circumstances determine, not limited here.

Specifically, in the above pad structure provided by the embodiment of the present invention, for each welding area, the purpose of setting the detection unit is to estimate the contact resistance of each welding area, so as to compensate for the contact resistance between areas The unevenness of the transmission signal caused by the unevenness. Therefore, preferably, in the above pad structure provided by the embodiment of the present invention, for each welding area, a current regulating circuit is further included;

The current regulation circuit is used to adjust the current in the welding area according to the output result of the comparison circuit, so as to realize the compensation for the inhomogeneity of the transmission signal caused by the inhomogeneity of the contact resistance between the areas.

It should be noted that the above-mentioned pad structure provided by the embodiments of the present invention can be applied to any device provided with a pad structure, and is especially suitable for devices requiring high signal uniformity.

Based on the same inventive concept, an embodiment of the present invention further provides a display device, including at least one pad structure as provided in the embodiments of the present invention. The display device may be any product or component with a display function such as a mobile phone, a tablet computer, a television, a monitor, a notebook computer, a digital photo frame, a navigator, and the like. Specifically, for the implementation of the display device, reference may be made to the above embodiments of the pad structure, and repeated descriptions will not be repeated.

Specifically, in the above-mentioned display device provided by the embodiment of the present invention, it further includes a display panel and a driver chip, and the driver chip inputs signals to the display panel through the bonding pad structure; wherein,

The first pad unit of the pad structure is located on the display panel, and the second pad unit of the pad structure is located on the driver chip; or

The first pad unit of the pad structure is located on the drive chip, and the second pad unit of the pad structure is located on the display panel.

Further, in the above-mentioned display device provided by the embodiment of the present invention, if the welding pad structure does not include a current regulating circuit, then the above-mentioned display device further includes a current regulating circuit, so that according to the output results of the comparison circuit in different welding areas of the welding pad structure The current of different welding areas is adjusted, so as to improve the problem of poor display device caused by non-uniform contact resistance of different welding areas of the welding pad structure. Specifically, in actual implementation, the current regulation circuit can be integrated on the driver chip.

Specifically, in the above-mentioned display device provided by the embodiment of the present invention, the above-mentioned pad structure can be used only in the place where the driver chip inputs signals to the display panel, and the existing pad structure can be used in other places. The above pad structure can also be used only at the place where the signal is input to the driver chip, and the above pad structure is used at both the place where the driver chip inputs the signal to the display panel and the place where the signal is input to the driver chip, which is not limited here.

Specifically, in the above-mentioned display device provided by the embodiment of the present invention, when the above-mentioned bonding pad structure is used at the place where the signal is input to the driving chip, the display device also includes a bonding pad structure for inputting signals to the driving chip, in order to be compatible with the above-mentioned display device. The bonding pad structures for inputting signals to the panel are different. Here, the bonding pad structure for inputting signals to the display panel is referred to as the first bonding pad structure, and the bonding pad structure for inputting signals to the driver chip is referred to as the second bonding pad structure. Specifically, the first pad unit of the second pad structure is located on the display panel, and the second pad unit of the second pad structure is located on the driver chip; or

The first pad unit of the second pad structure is located on the driving chip, and the second pad unit of the second pad structure is located on the display panel.

Further, in specific implementation, the above-mentioned display device provided by the embodiment of the present invention can estimate the contact resistance of the welding regions with different welding structures each time the display device is turned on and output the output results, and then follow the welding structure. The output results regulate the current of different welding areas until shutdown.

An embodiment of the present invention provides a pad structure and a display device. The pad structure includes a first pad unit and a second pad unit that are electrically connected by crimping. Since the first pad unit is divided into at least Two welding areas, which is equivalent to dividing the pad structure into at least two welding areas, and a detection unit is provided for each welding area. Through the detection pad and comparison circuit in the detection unit, the corresponding welding area can be estimated. The contact resistance between the first welding pad and the second welding pad in the area, so that the current of different welding areas can be adjusted according to the estimation results, so that the uneven contact resistance of different welding areas due to the welding pad structure can be improved The resulting impact on signal transmission, and then when the above pad structure is applied to a display device, can improve the problem of defective display products caused by non-uniform contact resistance of different welding areas of the pad structure.

Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims (10)

1. A welding pad structure comprises a first welding pad unit and a second welding pad unit which are electrically connected in a compression joint mode, wherein the first welding pad unit is provided with a plurality of first welding pads which are arranged side by side, the second welding pad unit is provided with a plurality of second welding pads which are arranged side by side, and each second welding pad is electrically connected with the corresponding first welding pad; the first welding pad unit is divided into at least two welding areas, and a plurality of groups of electrically connected second welding pads and first welding pads are arranged in each welding pad area; a detection unit for estimating contact resistance between a first bonding pad piece and a second bonding pad piece in the welding area is arranged aiming at each welding area; wherein the detection unit includes:

the two first detection bonding pads are positioned in the welding area, arranged side by side with the first bonding pads and positioned between the two adjacent first bonding pads at intervals, and the structures of the first detection bonding pads are the same as those of the first bonding pads;

the second detection welding gasket is positioned on the second welding pad unit and in the area corresponding to the first detection welding gasket, and the second detection welding gasket is connected with the two first detection welding gaskets in series; and

and the comparison circuit is electrically connected with the two first detection bonding pads which are connected in series and is used for determining the resistance value range of the two first detection bonding pads which are connected in series.

2. The bond pad structure of claim 1, wherein the second sensing bond pad structure is a planar structure.

3. The bond pad structure of claim 2, wherein the second sense bond pad has a surface area greater than twice the surface area of the second bond pad.

4. Bond pad structure as claimed in any one of claims 1 to 3, wherein the comparison circuit is a multi-stage comparison circuit; wherein,

the first-stage comparison sub-circuit is used for comparing the resistance values of the two first detection bonding pads which are connected in series with a reference resistance corresponding to the first-stage comparison sub-circuit, and outputting a first output signal if the resistance values are smaller than the reference resistance; if the reference resistance is larger than the reference resistance, outputting a second output signal;

the other comparison sub-circuits at each stage except the first comparison sub-circuit are used for comparing the resistance values of the two first detection bonding pads connected in series with the reference resistance corresponding to the comparison sub-circuit at the current stage after receiving a second output signal sent by the comparison sub-circuit at the previous stage, and outputting a first output signal if the resistance values are smaller than the reference resistance; if the reference resistance is larger than the reference resistance, outputting a second output signal;

except the last stage of comparison sub-circuit, the rest of comparison sub-circuits at each stage are also used for outputting a second output signal to the next stage of comparison sub-circuit when the comparison sub-circuit at the current stage outputs the second output signal;

the resistance value of the reference resistor corresponding to each stage of the comparison sub-circuit increases along with the increase of the stage number.

5. The bond pad structure of claim 4, wherein the comparison circuit is a two-stage comparison circuit.

6. The bond pad structure of claim 5, wherein the first stage comparator circuit; the method specifically comprises the following steps: the circuit comprises a first reference voltage end, a second reference voltage end, a positive power supply, a negative power supply, a first reference resistor and a first voltage comparator; wherein,

a positive phase input end of the first voltage comparator is connected with a first end of the first reference resistor, a negative phase input end of the first voltage comparator is connected with a first reference voltage end, a first power supply input end of the first voltage comparator is connected with a positive power supply, a second power supply input end of the first voltage comparator is connected with a negative power supply, and an output end of the first voltage comparator is respectively connected with a first output signal end and a second-stage comparison sub-circuit;

two first detection bonding pads connected in series are connected between the second reference voltage end and the first end of the first reference resistor, and the second end of the first reference resistor is grounded;

the voltage of the second reference voltage terminal is equal to twice the voltage of the first reference voltage terminal.

7. The bond pad structure of claim 6, wherein the second-level comparison sub-circuit specifically comprises: a second reference resistor and a second voltage comparator; wherein,

the positive phase input end of the second voltage comparator is connected with the first end of the second reference resistor and the first end of the first reference resistor respectively, the negative phase input end of the second voltage comparator is connected with the first reference voltage end, the first power supply input end of the second voltage comparator is connected with the output end of the first voltage comparator, the second power supply input end of the second voltage comparator is connected with the negative power supply, and the output end of the second voltage comparator is connected with the second output signal end.

8. The solder pad arrangement of claim 4, further comprising, for each of the soldering regions, a current regulating circuit;

the current adjusting circuit is used for adjusting the current of the welding area according to the output result of the comparison circuit.

9. A display device, comprising a bond pad structure as claimed in any one of claims 1 to 8.

10. The display device according to claim 9, further comprising a display panel and a driving chip, the driving chip inputting a signal to the display panel through the pad structure; wherein,

the first welding pad unit of the welding pad structure is positioned on the display panel, and the second welding pad unit of the welding pad structure is positioned on the driving chip; or

The first welding pad unit of the welding pad structure is positioned on the driving chip, and the second welding pad unit of the welding pad structure is positioned on the display panel.