TW201811121A - Electrostatic discharge protection apparatus and electrostatic discharge protection method thereof - Google Patents

Abstract

An electrostatic discharge (ESD) protection apparatus and an ESD protection method are provided. The ESD protection apparatus includes a flexible circuit board, a chip, and a plurality of first transmission conductive wires. The flexible circuit board has at least one first input output (I/O) terminal and at least one second I/O terminal being respectively coupled to a circuit board and a glass substrate. The chip is disposed on the flexible circuit board and has at least one I/O pad and a dummy pad, and a plurality of ESD protection circuit coupled to the I/O pad and the dummy pad respectively. The first transmission conductive wires are formed on the flexible circuit board and coupled the first I/O terminal, the dummy pad and the I/O pad in series and in sequence.

Description

Electrostatic discharge protection device and method

The invention relates to an electrostatic discharge protection device, and more particularly to an electrostatic discharge protection device constructed by using a flexible circuit board wiring.

In the technical field of display devices, in order to ensure the reliability of the display device, it is an important subject to improve the electrostatic discharge protection capability of the display device. In the conventional technical field, a variety of different designs are often performed on a chip to improve the discharge capability of the electrostatic discharge current that the chip can perform, so as to improve the level of electrostatic discharge protection of the entire display device. However, such a method often requires the wafer to provide a sufficiently large wafer area to set the electrostatic discharge circuit, resulting in an increase in the wafer area. In the display driving chip, since the display driving chip needs to provide a large number of input and output channels, when setting up a high-performance electrostatic discharge circuit, a large amount of chip area is occupied, and the size of the chip (such as (Height) has increased significantly, increasing costs and reducing price competitiveness.

The invention provides an electrostatic discharge protection method for an electrostatic discharge protection device, which effectively improves the electrostatic discharge protection level.

The electrostatic discharge protection device of the present invention includes a flexible circuit board, a chip, and a plurality of first transmission wires. The flexible circuit board has at least one first input-output terminal and at least one second input-output terminal connected to the circuit board and the glass substrate, respectively. The chip is arranged on a flexible circuit board. The chip has at least one input-output pad and a dummy pad, and a plurality of electrostatic discharge circuits respectively coupled to the input-output pad and the dummy pad. The first transmission wire is formed on the flexible circuit board, and the first input-output terminal, the dummy pad and the input-output pad are coupled in series in sequence.

The electrostatic discharge protection method of the present invention comprises: disposing a wafer on a flexible circuit board, wherein the flexible circuit board has at least one first input-output terminal and at least one second input-output terminal connected to the circuit board and the glass substrate, respectively, and the wafer has at least An input-output pad and a dummy pad; a plurality of electrostatic discharge circuits respectively coupled to the input-output pad and the dummy pad are provided on the chip; and a plurality of first wires are formed on the flexible circuit board to make the first The input-output terminal, the dummy pad and the input-output pad are coupled in series in order.

Based on the above, the present invention forms a plurality of transmission wires on a flexible circuit board carrying a chip, so that the first input and output terminals coupled to the circuit board, the dummy pads on the chip, and the input and output pads are sequentially coupled in series. When the electrostatic discharge phenomenon occurs, the electrostatic discharge current can first flow to the dummy pad through the transmission wire on the flexible circuit board to be released through the electrostatic discharge protection circuit connected to the dummy pad. In this way, the level of electrostatic discharge protection can be improved without changing the size of the wafer.

In order to make the above features and advantages of the present invention more comprehensible, embodiments are hereinafter described in detail with reference to the accompanying drawings.

Please refer to FIG. 1, which is a schematic diagram of an electrostatic discharge protection device according to an embodiment of the present invention. The ESD protection device 100 includes a chip 110, a flexible circuit board 120, and a plurality of transmission wires WIR1 to WIR3 formed on the flexible circuit board 120. The chip 110 is carried on a flexible circuit board 120. In this embodiment, the chip may be a display driving chip or other types of chips, and the flexible circuit board 120 may be a chip on film (COF). Flexible circuit board.

The flexible circuit board 120 has a plurality of input and output terminals COFVS1-COFVS2 respectively coupled to the circuit board 101 and the glass substrate 102. The circuit board 101 may be a printed circuit board, and the input and output terminals COFVS1 are used as the chip 110 and the circuit board 101. Signal transmission medium on the circuit elements. The glass substrate 102 may be a display panel, and the input / output terminal COFVS2 is used as a medium for the chip 110 to transmit the driving signal to the glass substrate 102. A medium for transmitting signals by circuit elements on the circuit board 101. The number of input and output terminals COFVS1-COFVS2 is not limited. The drawing in FIG. 1 is only an illustrative example. The number of input and output terminals COFVS1-COFVS2 can be set according to requirements. The chip 110 has an input / output pad VS1 and a dummy pad DUM1. The number of input / output pads on the chip 110 is not limited, and one input / output pad VS1 shown in the figure is only an illustrative example. In fact, the chip 110 usually has multiple input / output pads.

The important point is that in this embodiment, the coupling method between the input / output terminal COFVS1 and the input / output pad VS1 is coupled through the transmission wire WIR1 and the dummy pad DUM1, and the dummy pad DUM1 is connected through the transmission wire WIR1. It is coupled to the input / output pad VS1. That is, the input-output terminal COFVS1, the dummy pad DUM1, and the input-output pad VS1 are connected in series through the transmission wires WIR1 and WIR2, respectively. The transmission wires WIR1 and WIR2 are formed on the flexible circuit board 120.

On the other hand, another transmission wire WIR3 formed on the flexible circuit board 120 is coupled between the input / output terminal COFVS2 and the input / output pad VS1.

It is worth noting that the input and output pads VS1 and the dummy pads DUM1 on the chip 110 are respectively coupled to the electrostatic discharge circuits ESD1 and ESD2.

When the electrostatic discharge phenomenon occurs on the input and output terminal COFVS1, the electrostatic discharge current is first transmitted to the dummy pad DUM1 through the transmission wire WIR1, and the electrostatic discharge current is conducted through the electrostatic discharge circuit ESD2 coupled to the dummy pad DUM1. Catharsis. In this way, the energy of the electrostatic discharge current flowing to the input / output pad VS1 will be greatly reduced (or even 0), and these residual electrostatic discharge currents can be passed through the electrostatic discharge coupled to the input / output pad VS1. The circuit ESD1 performs further discharge of the electrostatic discharge current and effectively achieves the action of electrostatic discharge protection.

From the above description, it can be known that the embodiment of the present invention uses the electrostatic discharge circuit ESD2 coupled to the dummy pad DUM1 to perform the prior electrostatic discharge current discharge, which can effectively prevent the core circuit in the chip 110 connected to the input and output pad VS1 from being affected. The electrostatic discharge current is destroyed. In the embodiment of the present invention, the electrostatic discharge circuit ESD1 coupled to the input / output pad VS1 is used to perform the next discharge of the electrostatic discharge current to complete the discharge operation of the electrostatic discharge current, thereby achieving the goal of electrostatic discharge protection.

Please refer to FIG. 2 below, which illustrates a schematic diagram of an electrostatic discharge protection device according to another embodiment of the present invention. The electrostatic discharge protection device 200 includes a chip 210, a flexible circuit board 220, and a plurality of transmission wires WIR1 to WIR4 formed on the flexible circuit board 220. The chip 210 is carried on the flexible circuit board 220. The chip 210 further includes an input / output pad VS1 and a dummy pad DUM1. The flexible circuit board 220 has input and output terminals COFVS1 and COFVS2.

In addition, a plurality of transmission wires WIR1-WIR4 are formed on the flexible circuit board 220. Among them, the transmission wire WIR1 is coupled to the input / output terminal COFVS1, and is coupled to the transmission wires WIR2 and WIR4. The other end of the transmission wire WIR2 is coupled to the dummy pad DUM1 on the chip 210, and the dummy pad DUM1 is coupled to the input / output pad VS1 on the chip 210 through the transmission wire WIR3. The other end of the transmission wire WIR4 is coupled to the input / output terminal COFVS2.

In this way, the input and output terminals COFVS1, the dummy pad DUM1, and the input and output pads VS1 are connected in series through the transmission wires WIR1, WIR2, and WIR3. From another perspective, the input and output terminals COFVS2, the dummy pad DUM1, and the input and output pads VS1 are connected in series through the transmission wires WIR4, WIR2, and WIR3.

The chip 210 is respectively configured with electrostatic discharge circuits ESD2 and ESD1 corresponding to the dummy pad DUM1 and the input-output pad VS1, and the dummy pad DUM1 and the input-output pad VS1 are respectively coupled to the electrostatic discharge circuits ESD2 and ESD1.

In this embodiment, when the electrostatic discharge phenomenon occurs on the input and output terminals COFVS1, the corresponding electrostatic discharge current can be transmitted to the dummy pad DUM1 along with the transmission wires WIR1 and WIR2, and is coupled to the dummy pad DUM1 through The electrostatic discharge circuit ESD2 performs a current release operation in the early stage. If the electrostatic discharge circuit ESD2 fails to fully discharge the electrostatic discharge current, the residual electrostatic discharge current can be transmitted to the input / output pad VS1 through the transmission wire WIR3, and further current discharge action is performed through the electrostatic discharge circuit ESD1.

On the other hand, when the electrostatic discharge phenomenon occurs on the input and output terminals COFVS2, the corresponding electrostatic discharge current can be transmitted to the dummy pad DUM1 along with the transmission wires WIR4, WIR2, and through the dummy pad DUM1. The electrostatic discharge circuit ESD2 performs a current release operation in the early stage. If the electrostatic discharge circuit ESD2 fails to fully discharge the electrostatic discharge current, the residual electrostatic discharge current can be transmitted to the input / output pad VS1 through the transmission wire WIR3, and further current discharge action is performed through the electrostatic discharge circuit ESD1.

In this embodiment, the electrostatic discharge circuit ESD2 coupled to the input and output terminals COFVS1 or COFVS2 through the dummy pad DUM1 is used to release the prior electrostatic discharge current, and then conducted through the electrostatic discharge circuit ESD1 coupled to the input and output pad VS1. The next step of discharging the electrostatic discharge current is to complete the discharging action of the electrostatic discharge current and achieve the goal of electrostatic discharge protection.

Please refer to FIG. 3A and FIG. 3B, FIG. 3A and FIG. 3B are schematic diagrams of electrostatic discharge protection devices according to different embodiments of the present invention, respectively. The implementation of FIG. 3A and FIG. 3B are extended implementations of the embodiment of FIG. 1 of the present application. In FIG. 3A, the wafer 310 of the electrostatic discharge protection device 300 is further provided with an auxiliary dummy pad ADUM1 and an auxiliary electrostatic discharge circuit AESD1 coupled to the auxiliary dummy pad ADUM1. The auxiliary dummy pad ADUM1 and the dummy pad DUM1 can be electrically coupled through a wire IWIR. The wire IWIR may be formed on the wafer 310, and the wire IWIR may be constructed through any material on the wafer 310 for forming a wire.

In the embodiment of FIG. 3A, when the electrostatic discharge phenomenon occurs, the corresponding electrostatic discharge current can be conducted to the auxiliary dummy pad ADUM1, and then released through the auxiliary electrostatic discharge circuit AESD1, and then coupled to the dummy pad. The electrostatic discharge circuit ESD2 of ADUM1 performs further energy release. If there is still residual energy that cannot be released, the energy can be released through the electrostatic discharge circuit ESD1 coupled to the input / output pad VS1.

In another aspect, the number of auxiliary dummy pads may be plural. In FIG. 3B, the auxiliary dummy pads ADUM1 and ADUM2 are provided on the chip 310, and the auxiliary electrostatic discharge circuits AESD1 and AESD2 corresponding to the auxiliary dummy pads ADUM1 and ADUM2, respectively. The auxiliary dummy pads ADUM1 and ADUM2 are respectively coupled to the auxiliary electrostatic discharge circuits AESD1 and AESD2. The auxiliary dummy pads ADUM1 and ADUM2 are coupled to the input / output terminal COFVS1 through a parallel transmission wire. When the electrostatic discharge phenomenon occurs, the corresponding electrostatic discharge current can be conducted to the auxiliary dummy pads ADUM1 and ADUM2 first, and the energy release action can be synchronized through the auxiliary electrostatic discharge circuits AESD1 and AESD2, and the ability of the electrostatic discharge current can be improved.

Please refer to FIG. 4A and FIG. 4B, FIG. 4A and FIG. 4B are schematic diagrams of electrostatic discharge protection devices according to different embodiments of the present invention, respectively. The implementation in FIG. 4A and FIG. 4B is an extended implementation of the embodiment in FIG. 2 of the present application. Similar to FIGS. 3A and 3B, one or more auxiliary dummy pads ADUM1 and ADUM2 and corresponding auxiliary electrostatic discharge circuits AESD1 and AESD2 are arranged on the chip 410, and the auxiliary dummy pads ADUM1 and ADUM2 are electrically coupled to each other. , And coupled with the dummy pad DUM1. In this way, when the electrostatic discharge phenomenon occurs, the corresponding electrostatic discharge current can be conducted to one or more auxiliary dummy pads ADUM1 and ADUM2 first, and carried out through one or more auxiliary electrostatic discharge circuits AESD1 and AESD2. The energy is released, and further energy is released through the electrostatic discharge circuit ESD2 coupled to the dummy pad ADUM1. If there is still residual energy that cannot be released, the energy can be released through the electrostatic discharge circuit ESD1 coupled to the input / output pad VS1. Effectively improve the electrostatic discharge protection level.

Please refer to FIG. 5 below, which illustrates a flowchart of an electrostatic discharge protection method according to an embodiment of the present invention. In step S510, the chip is arranged on a flexible circuit board, wherein the flexible circuit board has at least one first input-output terminal and at least one second input-output terminal connected to the circuit board and the glass substrate, respectively, and the chip has at least one input-output pad and Dummy pads. Next, in step S520, a plurality of electrostatic discharge circuits respectively coupled to the input / output pads and the dummy pads are provided on the wafer, and in step S530, a plurality of first wires are formed on the flexible circuit board so that the first An input-output terminal, a dummy pad and an input-output pad are coupled in series in sequence. In this way, when the electrostatic discharge phenomenon occurs, the electrostatic discharge current can be conducted to the dummy pad first, and the energy discharge action can be performed through the electrostatic discharge circuit corresponding to the dummy pad, thereby improving the level of electrostatic discharge protection.

In addition, in the embodiment of the present invention, a method of configuring one or more auxiliary dummy pads and an auxiliary electrostatic discharge circuit can be used to improve the electrostatic discharge capability and further improve the level of electrostatic discharge protection.

The implementation details of the above steps have been described in detail in the foregoing multiple embodiments and implementations, and will not be repeated here.

In summary, in the present invention, a transmission wire is formed on a flexible circuit board, and the electrostatic discharge current is first passed through the dummy pad on the wafer through the transmission wire, and the energy discharge action is performed by the electrostatic discharge circuit corresponding to the dummy pad. In this way, without changing the layout of the chip, only by modifying the wiring on the flexible circuit board, the level of electrostatic discharge protection can be effectively improved, and the production cost required for the chip can be reduced.

Although the present invention has been disclosed as above with the examples, it is not intended to limit the present invention. Any person with ordinary knowledge in the technical field can make some modifications and retouching without departing from the spirit and scope of the present invention. The protection scope of the present invention shall be determined by the scope of the attached patent application.

100, 200, 300, 400‧‧‧ electrostatic discharge protection devices
110, 210, 310, 410‧‧‧ chips
120‧‧‧ flexible circuit board
WIR1 ~ WIR4‧‧‧Transmission Conductor
COFVS1, COFVS2‧‧‧ input and output terminals
VS1‧‧‧I / O Pad
DUM1‧‧‧Dummy pad
ESD1, ESD2‧‧‧electrostatic discharge circuit
101‧‧‧Circuit Board
102‧‧‧ glass substrate
AESD1, AESD2‧‧‧Auxiliary electrostatic discharge circuit
ADUM1, ADUM2‧‧‧Auxiliary dummy pads
IWIR‧‧‧Wire
S510 ~ S530‧‧‧‧Procedure for electrostatic discharge protection

FIG. 1 is a schematic diagram of an electrostatic discharge protection device according to an embodiment of the present invention. FIG. 2 is a schematic diagram of an electrostatic discharge protection device according to another embodiment of the present invention. 3A and 3B are schematic diagrams of electrostatic discharge protection devices according to different embodiments of the present invention, respectively. 4A and 4B are schematic diagrams of electrostatic discharge protection devices according to different embodiments of the present invention, respectively. FIG. 5 is a flowchart of an electrostatic discharge protection method according to an embodiment of the present invention.

100‧‧‧ Electrostatic discharge protection device

110‧‧‧Chip

120‧‧‧ flexible circuit board

WIR1 ~ WIR3‧‧‧Transmission Conductor

COFVS1, COFVS2‧‧‧ input and output terminals

VS1‧‧‧I / O Pad

DUM1‧‧‧Dummy pad

ESD1, ESD2‧‧‧electrostatic discharge circuit

101‧‧‧Circuit Board

102‧‧‧ glass substrate

Claims (10)

An electrostatic discharge protection device includes: a flexible circuit board having at least a first input-output terminal and at least a second input-output terminal connected to a circuit board and a glass substrate, respectively; a chip arranged on the flexible circuit board The chip has at least one input-output pad and a dummy pad, and a plurality of electrostatic discharge circuits respectively coupled to the input-output pad and the dummy pad; and a plurality of first transmission wires formed in the flexible On the circuit board, the first input-output terminal, the dummy pad and the input-output pad are coupled in series in sequence. The electrostatic discharge protection device according to item 1 of the scope of patent application, wherein the second input / output terminal is coupled to the input / output pad or the first input / output terminal through a second transmission wire. The electrostatic discharge protection device according to item 1 of the scope of patent application, wherein when an electrostatic discharge current occurs on the first input / output terminal, the electrostatic discharge current flows to the dummy pad and is coupled to the dummy pad The electrostatic discharge circuit performs current discharge. The electrostatic discharge protection device according to item 1 of the scope of patent application, wherein the chip further includes: at least one auxiliary dummy pad disposed adjacent to the dummy pad; and at least one auxiliary electrostatic discharge circuit coupled to the auxiliary dummy A solder pad, wherein the at least one auxiliary dummy solder pad is electrically coupled to the dummy solder pad. The electrostatic discharge protection device according to item 3 of the scope of patent application, wherein when an electrostatic discharge current occurs on the first input / output terminal, the electrostatic discharge current flows to the dummy pad and the at least one auxiliary dummy pad, Current is leaked through an electrostatic discharge circuit coupled to the dummy pad and an auxiliary electrostatic discharge circuit coupled to the at least one auxiliary dummy pad. An electrostatic discharge protection method includes: arranging a chip on a flexible circuit board, wherein the flexible circuit board has at least a first input-output terminal and at least a second input-output terminal connected to a circuit board and a glass, respectively. A substrate, the wafer having at least one input / output pad and a dummy pad; a plurality of electrostatic discharge circuits respectively coupled to the input / output pad and the dummy pad are provided on the wafer; and on the flexible circuit board A plurality of first wires are formed, and the first input-output terminal, the dummy pad, and the input-output pad are coupled in series in sequence. The electrostatic discharge protection method according to item 6 of the patent application scope, further comprising: forming a second wire on the flexible circuit board, so that the second input / output terminal is coupled to the second input / output terminal through the second transmission wire. I / O pads or the first I / O terminal. The electrostatic discharge protection method according to item 6 of the scope of patent application, wherein when an electrostatic discharge current occurs on the first input / output terminal, the electrostatic discharge current is caused to flow to the dummy pad and is coupled to the dummy pad by The pad's electrostatic discharge circuit vents current. The electrostatic discharge protection method according to item 6 of the scope of patent application, further comprising: providing at least one auxiliary dummy pad on the wafer, the at least one auxiliary dummy pad being disposed adjacent to the dummy pad; on the wafer; At least one auxiliary electrostatic discharge circuit is provided thereon to be coupled to the at least one auxiliary dummy pad; and the at least one auxiliary dummy pad is electrically coupled to the dummy pad. The electrostatic discharge protection method according to item 9 of the scope of patent application, wherein when an electrostatic discharge current occurs on the first input / output terminal, the electrostatic discharge current is caused to flow to the dummy pad and the at least one auxiliary dummy pad Current leakage through an electrostatic discharge circuit coupled to the dummy pad and an auxiliary electrostatic discharge circuit coupled to the at least one auxiliary dummy pad.