A GATE DRIVER CIRCUIT BASING ON IGZO PROCESS

• US 20160247476A1
• Filed: 09/19/2014
• Published: 08/25/2016
• Est. Priority Date: 09/10/2014
• Status: Active Grant

• Current Assignee: Shenzhen China Star Optoelectronics Technology Co., Ltd. (TCL Technology Group Corp.)
• Original Assignee: Shenzhen China Star Optoelectronics Technology Co., Ltd. (TCL Technology Group Corp.)
• Inventors: XIAO, Juncheng
• Granted Patent: US 9,472,155 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G09G 2300/0408 Integration of the drivers onto the display substrate
• CPC Class Codes: G09G 2300/0465 Improved aperture ratio, e.g. by size reduction of the pixel circuit, e.g. for improving the pixel density or the maximum displayable luminance or brightness
• CPC Class Codes: G09G 2300/0871 with level shifting
• CPC Class Codes: G09G 2310/0286 Details of a shift registers arranged for use in a driving circuit
• CPC Class Codes: G09G 3/3677 suitable for active matrices only
• CPC Class Codes: G11C 19/28 using semiconductor elements G11C19/14, G11C19/36 take precedence

Abstract

The present invention provides a gate driver basing on IGZO process, comprising: GOAs in cascade connection comprising a N^th-stage GOA, wherein the N^th-stage GOA further comprising: a pull-up control part 100, a pull-up part 200, a transfer part 300, a pull-down part 400, a pull-down holding part 500, a boost part 600, a first negative supply VSS1, a second negative supply VSS2, a third negative supply VSS3, which are three gradually decreasing negative supplies and pull down an output terminal G(N), a first node Q(N), a second node P(N), and a driving single ST(N) to prevent the electrical leakage of TFTs effectively. And channels of the TFT switches of the gate driver basing on the IGZO process are oxide semiconductor channels.

Claims

1. A gate driver basing on IGZO process, comprising:

GOAs in cascade connection comprising a N^th-stage GOA, wherein the N is a positive integer, wherein the N^th-stage GOA further comprising;

a pull-up part having a first transistor, wherein a gate of the first transistor electrically connects a first node, a source of the first transistor electrically connects a first clock signal, a drain of first transistor electrically connects an output terminal, wherein the first transistor is used for outputting signals on the output terminal according to the first clock signal;

a transfer part having a second transistor, wherein a gate of the second transistor electrically connects the first node, a source of the second transistor electrically connects the first clock signal, a drain of the second transistor electrically connects a driving signal terminal, wherein the second transistor is used for outputting the diving signal from the driving signal terminal according to the first clock signal;

a pull-up control part having a third transistor, wherein a gate of the third transistor electrically connects the driving signal terminal of a N−

1^th-stage GOA, a source of the third transistor electrically connects the output terminal of the N−

1^th-stage GOA, the drain of the third transistor electrically connects the first node, wherein the third transistor is used for conducting the pull-up part according to the driving signal from the driving signal terminal;

a pull-down holding part having a first pull-down holding circuit, the first pull-down holding circuit further comprising a fourth transistor, a fifth transistor, a sixth transistor, a seventh transistor, a eighth transistor, a ninth transistor, and a tenth transistor;

wherein a gate of the fourth transistor electrically connects the first clock signal, a source of the fourth transistor electrically also connects the first clock signal, a drain of fourth transistor electrically connects a second node, a gate of the fifth transistor electrically connects the driving signal terminal, a source of the fifth transistor electrically connects the second node, a drain of the fifth transistor electrically connects a second negative supply, a gate of the sixth transistor electrically connects the driving signal terminal of the N−

1^st-stage GOA, a source of the sixth transistor electrically connects the second node, a drain of the sixth transistor electrically connects the second negative supply, a gate of the seventh transistor electrically connects the second clock signal, a source of the seventh transistor electrically connects the first clock signal, a drain of the seventh transistor electrically connects the second node, a gate of the eighth transistor electrically connects the second node, a source of the eighth transistor electrically connects the output terminal, a drain of the eighth transistor electrically connects a first negative supply, a gate of the ninth transistor electrically connects the second node, a source of the ninth transistor electrically connects the first node, a drain of the ninth transistor electrically connects the second negative supply, a gate of the tenth transistor electrically connects the second node, a source of the tenth transistor electrically connects the driving signal terminal, a drain of the tenth transistor electrically connects a third negative supply, wherein the fifth transistor and the sixth transistor are used for pulling down the electrical potential of the second node when the driving signal terminal is in a high electrical potential;

a pull-down part having a thirteenth transistor and a fifteenth transistor, wherein a gate of the thirteenth transistor electrically connects a driving signal terminal of the N+1^th-stage GOA, a source of the thirteenth transistor electrically connects the driving signal terminal, a drain of the thirteenth transistor electrically connects the third negative supply, a gate of the fifteenth transistor electrically connects the driving signal terminal of the N+1^th-stage GOA, a source of the fifteenth transistor electrically connects the first node, a drain of the fifteenth transistor electrically connects the driving signal terminal, wherein the thirteenth transistor is used for pulling down the electrical potential of the driving signal terminal to prevent the electrical leakages of the fifteenth transistor and the sixth transistor when the gate driver is not working, wherein the fifth transistor is used for pulling down the electrical potential of the first node rapidly when the outputting terminal finishes outputting;

a boost part having a capacitor, wherein the capacitor electrically connects the first node and the output terminal, wherein the boost part is used for pulling up the electrical potential of the first node again to make sure the outputting terminal of the pull-up part output normally; and

channels of the TFT switches of the gate driver basing on the IGZO process are oxide semiconductor channels.

2. The gate driver basing on IGZO process according to claim 1, wherein the gate and source of the third transistor are both electrically connect the starting signal within the first-stage connection of the gate driver.

3. The gate driver basing on IGZO process according to claim 1, wherein the gate of the thirteenth transistor and the gate of the fifteenth transistor both electrically connect the starting signal within the last-stage connection of the gate driver.

4. The gate driver basing on IGZO process according to claim 1, wherein the pull-down holding further comprising a second pull-down holding circuit having a eleventh transistor and a twelfth transistor;

wherein a gate of the eleventh transistor electrically connects a driving signal terminal of the N+2^th-stage GOA, a source of the eleventh transistor electrically connects the first node, a drain of the eleventh transistor electrically connects the second negative supply, a gate of the twelfth transistor electrically connects the driving signal terminal of the N+2^th-stage GOA, a source of the twelfth transistor electrically connects the output terminal, a drain of the twelfth transistor electrically connects the first negative supply.

5. The gate driver basing on IGZO process according to claim 4, wherein the gate of the eleventh transistor and the gate of the twelfth transistor both electrically connect the driving signal of the second-stage GOA within the last-stage connection of the gate driver.

6. The gate driver basing on IGZO process according to claim 1, wherein the pull-down part further comprises a fourteenth transistor, wherein a gate of the fourteenth transistor electrically connects the driving signal terminal of the N+1^th-stage GOA, a source of the fourteenth transistor electrically connects the output terminal, a drain of the fourteenth transistor electrically connects the first negative supply.

7. The gate driver basing on IGZO process according to claim 6, wherein the gate of the fourteenth transistor electrically connects the starting signal within the last-stage connection of the gate driver.

8. The gate driver basing on IGZO process according to claim 1, wherein the electrical potential of the first negative supply is higher than the electrical potential of the second negative supply and the electrical potential of the second negative supply is higher than the electrical potential of the third negative supply.

9. The gate driver basing on IGZO process according to claim 8, wherein the first negative supply is used for pulling down the electrical potential of the output terminal, the second negative supply is used for pulling down the electrical potential of the first node and the second node, and third negative supply is used for pulling down the electrical potential of the driving output terminal.

10. The gate driver basing on IGZO process according to claim 1, wherein the first clock signal and the second clock signal are high frequency clock signals with 180 degree phase difference from each other.