Display device with connection board and method of testing pad contact state thereof

Patent metadata

Field	Value
Publication number	US-11094237-B2
Application number	US-202016847663-A
Country	US
Kind code	B2
Filing date	Apr 14, 2020
Priority date	Jun 20, 2019
Publication date	Aug 17, 2021
Grant date	Aug 17, 2021

Abstract

A display device includes a display panel including first to fourth panel pads and a connection board including first to fourth connection board pads coupled to the first to fourth pads, respectively. The first and second panel pads are electrically connected to each other, and the third and fourth panel pads are electrically connected to each other. The connection board includes a driving circuit which generates a first test result signal based on a first panel test signal transmitted to the first connection board pad and a first panel feedback signal received from the second connection board pad, generates a second test result signal based on a second panel test signal transmitted to the third connection board pad and a second panel feedback signal received from the fourth connection board pad, and sequentially outputs the first and second test result signals as a test result signal.

First claim

What is claimed is:

1. A display device, comprising:
a display panel comprising first to fourth panel pads; and
a connection board comprising first to fourth connection board pads coupled to the first to fourth panel pads, respectively,
wherein the first panel pad and the second panel pad are electrically connected to each other,
the third panel pad and the fourth panel pad are electrically connected to each other, and
the connection board comprises a driving circuit which is connected to the first to fourth connection board pads, generates a first test result signal based on a first panel test signal transmitted to the first connection board pad and a first panel feedback signal received from the second connection board pad, generates a second test result signal based on a second panel test signal transmitted to the third connection board pad and a second panel feedback signal received from the fourth connection board pad, and sequentially outputs the first test result signal and the second test result signal as a test result signal.

2. The display device of claim 1 , wherein the driving circuit is an integrated circuit, and
the connection board is composed of a chip-on-film, on which the driving circuit is mounted.

3. The display device of claim 1 , wherein the first panel pad and the second panel pad are arranged in a side region of the display panel, and
the third panel pad and the fourth panel pad are spaced apart from the first panel pad and the second panel pad and are arranged in an opposite side region of the display panel.

4. The display device of claim 1 , wherein the driving circuit generates the first test result signal of a first level, when a first difference between the first panel test signal and the first panel feedback signal is smaller than a predetermined value, and generates the first test result signal of a second level different from the first level, when the first difference is greater than or equal to the predetermined value, and
the driving circuit generates the second test result signal of the first level, when a second difference between the second panel test signal and the second panel feedback signal is smaller than the predetermined value, and generates the second test result signal of the second level, when the second difference is greater than or equal to the predetermined value.

5. The display device of claim 1 , wherein the display panel further comprises a plurality of panel pads,
the connection board further comprises a plurality of connection board pads coupled to the plurality of panel pads, respectively, and
at least one of the plurality of panel pads and the plurality of connection board pads is an image signal pad used to transmit an image signal.

6. The display device of claim 5 , wherein the first panel pad and the second panel pad are arranged at a side of the plurality of panel pads, and
the third panel pad and the fourth panel pad are arranged at an opposite side of the plurality of panel pads.

7. The display device of claim 6 , wherein the display panel further comprises a fifth panel pad and a sixth panel pad electrically connected to each other, and a seventh panel pad and an eighth panel pad electrically connected to each other,
the connection board further comprises fifth to eighth connection board pads coupled to the fifth to eighth panel pads, respectively, and
the driving circuit is electrically connected to the fifth to eighth connection board pads, further generates a third test result signal based on a fifth panel test signal transmitted to the fifth connection board pad and a third panel feedback signal received from the sixth connection board pad, generates a fourth test result signal based on a fourth panel test signal transmitted to the seventh connection board pad and a fourth panel feedback signal received from the eighth connection board pad, and sequentially outputs the first to fourth test result signals as the test result signal.

8. The display device of claim 7 , wherein the fifth to eighth panel pads are arranged between the plurality of panel pads.

9. The display device of claim 8 , wherein the connection board further comprises a connection board output pad, and
the driving circuit sequentially outputs the first to fourth test result signals to the connection board output pad, during one frame.

10. The display device of claim 9 , further comprising a main circuit board comprising an output receiving pad coupled to the connection board output pad,
wherein the main circuit board further comprises a main controller, which receives the first test result signal and the second test result signal through the output receiving pad.

11. The display device of claim 10 , wherein the main circuit board further comprises first to fourth main board pads,
the connection board further comprises first to fourth main contact pads coupled to the first to fourth main board pads, respectively, and
the driving circuit is electrically connected to the first to fourth main board pads, further generates a fifth test result signal based on a first main board test signal transmitted to the first main contact pad and a first main board feedback signal received from the second main contact pad, generates a sixth test result signal based on a second main board test signal transmitted to the third main contact pad and a second main board feedback signal received from the fourth main contact pad, and sequentially outputs the first to sixth test result signals as the test result signal.

12. The display device of claim 11 , wherein the driving circuit sequentially outputs the first to sixth test result signals to the connection board output pad, during one frame.

13. The display device of claim 11 , wherein the first main board pad and the second main board pad are arranged in a side region of the main circuit board, and
the third main board pad and the fourth main board pad are spaced apart from the first main board pad and the second main board pad and are arranged in an opposite side region of the main circuit board.

14. A display device, comprising:
a display panel comprising a plurality of panel pads;
a plurality of connection boards, each of which comprises first to fourth connection board pads and a connection board output pad; and
a main circuit board comprising a plurality of output receiving pads coupled to the connection board output pads of the plurality of connection boards,
wherein the plurality of panel pads comprises first and second panel pads electrically connected to each other, and third and fourth panel pads electrically connected to each other,
the first to fourth connection board pads of one of the plurality of connection boards are coupled to the first to fourth panel pads, respectively,
each of the plurality of connection boards comprises a driving circuit, and
the driving circuit of the one of the plurality of connection boards is electrically connected to the first to fourth connection board pads, generates a first test result signal based on a first panel test signal transmitted to the first connection board pad, a first panel feedback signal received from the second connection board pad, a second panel test signal transmitted to the third connection board pad, and a second panel feedback signal received from the fourth connection board pad, and outputs the first test result signal to the connection board output pad.

15. The display device of claim 14 , wherein each of the driving circuits is an integrated circuit, and
each of the plurality of connection boards is composed of a chip-on-film, on which the driving circuit

Assignees

• Samsung Display Co Ltd

Inventors

• Kim Sung-Jun
• Kwon Myung-Seok
• Kim Deok-Hwan
• Kim Yun-Tae
• Kim Jeong-Hyun
• Kim Hasook
• Park Bongchun

Classifications

• G09G3/006 Primary

  Electronic inspection or testing of displays and display drivers, e.g. of LED or LCD displays (testing individual LED's G01R31/2635; testing lamps G01R31/44; testing of optical features of LCD displays G02F1/1309) · CPC title

• H05K1/111

  Pads for surface mounting, e.g. lay-out · CPC title

• H05K1/147

  at least one of the printed circuits being bent or folded, e.g. by using a flexible printed circuit (H05K1/148 takes precedence) · CPC title

• G01R31/2884

  using dedicated test connectors, test elements or test circuits on the IC under test (G01R31/2855 takes precedence) · CPC title

• G09G2330/12

  Test circuits or failure detection circuits included in a display system, as permanent part thereof · CPC title