LED driver circuit and LED display apparatus

Patent metadata

Field	Value
Publication number	US-12444344-B2
Application number	US-202118268304-A
Country	US
Kind code	B2
Filing date	Nov 15, 2021
Priority date	Dec 17, 2020
Publication date	Oct 14, 2025
Grant date	Oct 14, 2025

Abstract

Disclosed in an embodiment of the present application is an LED driver circuit and an LED display apparatus. The LED driver circuit comprises: a first component area, which comprises a first driving channel group and a second driving channel group that are arranged symmetrically and comprise a same number of driving channels, respectively; and a second component area, which is provided with an analog ground pad connected to a substrate of the driving channels through a metal wire. According to the present application, chip internal noise can be effectively reduced, and accuracy of matching output currents of the driving channels can be improved to obtain good current consistency, thereby being beneficial to guarantee display effect of a LED display screen.

First claim

What is claimed is:

1. An LED driver circuit, comprising:
a first component area, comprising a first driving channel group and a second driving channel group, wherein the first driving channel group and the second driving channel group are symmetrically distributed, the first driving channel group and the second driving channel group respectively comprise a same number of driving channels;
a second component area, provided with an analog ground pad connected to a substrate of the driving channels through a metal wire,
wherein each of the driving channels comprises a common-source device module, a common-gate device module and an electrostatic protection module; the common-source device module comprises a first field effect transistor and the common-gate device module comprises a second field effect transistor, a source of the first field effect transistor is grounded, a source of the second field effect transistor is directly connected to a drain of the first field effect transistor and a drain of the second field effect transistor is directly connected to a corresponding output terminal for providing output current,
wherein in each of the driving channels, the first field effect transistor is disposed closer to a symmetry axis between the first driving channel group and the second driving channel group than the second field effect transistor,
wherein in the first component area:
the metal wire comprises a first metal line, a second metal line, a third metal line and a fourth metal line that extend in a same direction separately in parallel, the LED driver circuit further comprises a plurality of output pads and a plurality of power ground pads;
the output pads corresponding to the first driving channel are located between the first metal line and the second metal line, the output pads corresponding to the second driving channel are located between the third metal line and the fourth metal line, and the plurality of power ground pads are located between the second metal line and the third metal line.

2. The LED driver circuit according to claim 1 , wherein each of the driving channels further comprises:
an operational amplifier module, adjacent to the electrostatic protection module;
a blanking module, adjacent to the operational amplifier module and arranged at an edge of a driver chip comprising the LED driver circuit,
wherein
the common-source device module is disposed proximate to the symmetry axis between the first driving channel group and the second driving channel group; the common-gate device module is arranged adjacent to the common-source device module; the electrostatic protection module is arranged adjacent to the common-gate device module,
thus compared with the first field effect transistor in the common-source module, the second field effect transistor in the common-gate module is positioned closer to the electrostatic protection module.

3. The LED driver circuit according to claim 2 , wherein the common-source device modules in the driving channels of the first driving channel group are adjacent to the common-source device modules in the driving channels of the second driving channel group.

4. The LED driver circuit according to claim 2 , wherein,
in each one of the driving channels of the first driving channel group, the common-source device module, the common-gate device module, the electrostatic protection module, the operational amplifier module and the blanking module are sequentially arranged from right to left; and
in each one of the driving channels of the second driving channel group, the common-source device module, the common-gate device module, the electrostatic protection module, the operational amplifier module and the blanking module are sequentially arranged from left to right.

5. The LED driver circuit according to claim 2 , wherein each of the plurality of output pads, corresponds to a corresponding one of the driving channels, and is disposed at a position where the common-gate device module and the electrostatic protection module are adjacent to each other in that corresponding one of the driving channels.

6. The LED driver circuit according to claim 5 , wherein a number of the plurality of output pads is 16.

7. The LED driver circuit according to claim 5 , wherein each of the plurality of power ground pads, each of which corresponds to four corresponding ones of the driving channels and is disposed on the symmetry axis between the first driving channel group and the second driving channel group.

8. The LED driver circuit according to claim 7 , wherein a number of the plurality of power ground pads is 4.

9. The LED driver circuit according to claim 1 , wherein the metal wire has an even number of metal lines, which are symmetrically distributed.

10. The LED driver circuit according to claim 1 , wherein the metal wire comprises:
the first metal line is arranged on a left side of the output pads of the first driving channel group and connected to a substrate of the first driving channel group;
the second metal line is arranged between the output pads of the first driving channel group and the plurality of power ground pads, and connected to the substrate of the first driving channel group;
the third metal wire is arranged between the output pads of the second driving channel group and the plurality of power ground pads, and connected to a substrate of the second driving channel group;
the fourth metal wire is arranged on a right side of the output pads of the second driving channel group and connected to the substrate of the second driving channel group.

11. The LED driver circuit according to claim 1 , wherein the operational amplifier module comprises an amplifier, a gate of the first field effect transistor is connected to a first voltage input terminal, the drain of the first field effect transistor is connected to a source of the second field effect transistor, a drain of the second field effect transistor is connected to the corresponding output terminal, a gate of the second field effect transistor is connected to an output terminal of the amplifier, a first input terminal of the amplifier is connected to a second voltage input terminal, and a second input terminal of the amplifier is connected to the source of the second field effect transistor.

12. The LED driver circuit according to claim 1 , wherein each of the first field effect transistor and the second field effect transistor is an NMOS transistor.

13. The LED driver circuit according to claim 1 , wherein the number of the driving channels comprised by each of the first driving channel group and the second driving channel group is 8.

14. The LED driver circuit according to claim 1 , wherein the second component area is further provided with an analog power supply pad.

15. An LED display apparatus, comprising the LED driver circuit according to claim 1 .

16. The LED driver circuit according to claim 1 , wherein the first component area is arranged in a lower region of a driver chip which comprises the LED driver circuit, the second component area is arranged in an upper region of the driver chip, and the analog ground pad is arranged at an upper edge of the driver chip.

17. The LED driver circuit according to claim 1 , wherein in each of the driving channels,
compared with the first field effect transistor in the common-source module, the second field effect module in the common-gate module and the electrostatic protection module are positioned closer to the corresponding output terminal for that driving channel.

18. The LED driver circuit accor

Assignees

• Chipone Technology Beijing Co Ltd

Inventors

• Ma Yingjie

Classifications

• G09G2310/061

  for resetting or blanking · CPC title

• G09G2310/0291

  Details of output amplifiers or buffers arranged for use in a driving circuit · CPC title

• G09G2300/0408

  Integration of the drivers onto the display substrate · CPC title

• G09G3/32 Primary

  semiconductive, e.g. using light-emitting diodes [LED] · CPC title