Scanning driving circuit with pull-down maintain module and liquid crystal display apparatus with the scanning driving circuit

• US 10,262,609 B2
• Filed: 01/30/2016
• Issued: 04/16/2019
• Est. Priority Date: 10/31/2015
• Status: Active Grant

• Current Assignee: Wuhan China Star Optoelectronics Technology Co., Ltd. (TCL Technology Group Corp.)
• Original Assignee: Wuhan China Star Optoelectronics Technology Co., Ltd. (TCL Technology Group Corp.)
• Inventors: Dai, Ronglei
• Primary Examiner(s): Dicke, Chad M
• Application Number:
  US15/011,506
• Publication Number:
  US 20170124969A1
• Time in Patent Office: 1,172 Days
• CPC Class Codes: G09G 2310/0283 Arrangement of drivers for different directions of scanning
• CPC Class Codes: G09G 2310/0286 Details of a shift registers arranged for use in a driving circuit
• CPC Class Codes: G09G 2310/0289 Details of voltage level shifters arranged for use in a driving circuit
• CPC Class Codes: G09G 2310/061 for resetting or blanking
• CPC Class Codes: G09G 2310/08 Details of timing specific for flat panels, other than clock recovery
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence
• CPC Class Codes: G09G 3/3677 suitable for active matrices only

Abstract

The disclosure discloses a scanning driving circuit and a liquid crystal display apparatus, the scanning driving circuit including a first driving circuit and a second driving circuit, each of the first driving circuit and the second driving circuit including a number of driving units in cascade connections, and each of the driving units including: a forward and reverse scanning module to output a forward scanning signal, a reverse scanning signal and an optional signal; a pull-down maintain module connected to the forward and reverse scanning module and to receive the optional signal from the forward and reverse scanning module and output a pull down signal according to the optional signal; a control module connected to the forward and reverse scanning module and the pull-down maintain module; a reset module connected to the pull-down maintain module and the control module to reset the electrical potential of the scanning line.

Claims

1. A scanning driving circuit, the scanning driving circuit comprising a first driving circuit and a second driving circuit, the first driving circuit and the second driving circuit comprising a plurality of driving units in cascade connections, and each of the plurality of driving units in the first driving circuit and the second driving circuit comprising:

a forward and reverse scanning module to output a forward scanning signal, a reverse scanning signal and a pull-down signal;

a pull-down maintain module connected to the forward and reverse scanning module and to receive the pull-down signal from the forward and reverse scanning module and output a pull down signal according to the pull-down signal;

a control module connected to the forward and reverse scanning module and the pull-down maintain module, and to receive the forward scanning signal and the reverse scanning signal from the forward and reverse scanning module and the pull down signal from the pull-down maintain module then output a high electrical level or a low electrical level scanning driving signal, wherein the control module comprises a seventh to tenth controllable switches and a capacitor, an output terminal of the seventh controllable switch is directly connected to a control terminal of the tenth controllable switch and an output terminal of the tenth controllable switch is directly connected to the scanning line, directly connected to an output terminal of the ninth controllable switch and directly connected to a reset module;

a scanning line to transmit the scanning driving signal to the pixel unit; and

the reset module connected to the pull-down maintain module and the control module to reset the electrical potential of the scanning line;

wherein the forward and reverse scanning module further comprises a first controllable switch, and the reset module further comprises an eleventh controllable switch;

a control terminal of the first controllable switch in a first driving unit of the first driving circuit is directly connected to a first driving terminal, the control terminal of the first controllable switch in each of the rest of the driving units the first driving circuit is connected to an upper level scanning line, the control terminals of the eleventh controllable switches in all the driving units of the first driving circuit are directly connected to a second driving terminal;

the control terminal of the first controllable switch in a first driving unit of the second driving circuit is directly connected to the second driving terminal;

the control terminal of the first controllable switch in each of the rest of the driving units of the second driving circuit is connected to the upper level scanning line, the control terminals of the eleventh controllable switches in all the driving units of the second driving circuit are directly connected to the first driving terminal;

when the first driving terminal input a high electrical level signal and the second driving terminal inputs a low electrical level signal, all the driving units of the first driving circuit are conducted, and all the driving units of the second driving circuit are reset;

when the touch scanning is finished, the first driving terminal inputs a low electrical level signal and the second driving terminal inputs a high electrical level signal, all the driving units of the second driving circuit are conducted, and all the driving units of the first driving circuit are reset.

2. The scanning driving circuit according to claim 1, wherein the forward and reverse scanning module further comprises a second controllable switch, a control terminal of the first controllable switch is connected to an upper level scanning signal, an input terminal of the first controllable switch is connected to a forward scanning control potential, the output terminal of the first controllable switch is connected to the control module, the pull-down maintain module and an output terminal of the second controllable switch, an input terminal of the second controllable switch is connected to a reverse scanning control potential, and a control terminal of the second controllable switch is connected to a next level scanning signal.

3. The scanning driving circuit according to claim 2, wherein the pull-down maintain module further comprises a third to sixth controllable switches, a control terminal of the third controllable switch is connected to the forward scanning control potential, an input terminal of the third controllable switch is connected to a next level clock signal, an output terminal of the third controllable switch is connected to an output terminal of the fourth controllable switch, and a control terminal of the fifth controllable switch, a control terminal of the fourth controllable switch is connected to the reverse scanning control potential, an input terminal of the fourth controllable switch is connected to an upper level clock signal, an input terminal of the fifth controllable switch is connected to a turn on electrical potential terminal, an output terminal of the fifth controllable switch is connected to a control terminal of the sixth controllable switch, an output terminal of the sixth controllable switch is connected to the output terminal of the first controllable switch and an input terminal of the sixth controllable switch is connected to a turn off electrical potential terminal and the control module.

4. The scanning driving circuit according to claim 3, wherein a control terminal of the seventh controllable switches is connected to the open electrical potential terminal, an input terminal of the seventh controllable switch is connected to the output terminal of the first controllable switch, an input terminal of the tenth controllable switch is connected to a current level clock signal, a control terminal of the eighth controllable switch is connected to the output terminal of the first controllable switch, an input terminal of the eighth controllable switch is connected to the turn off electrical potential terminal, an output terminal of the eighth controllable switch is connected to the control terminal of the sixth controllable switch and a control terminal of the ninth controllable switch, an input terminal of the ninth controllable switch is connected to the turn off electrical potential terminal, an output terminal of the ninth controllable switch is connected to the scanning line, the capacitor is connected between the control terminal and the input terminal of the ninth controllable switch, wherein the ninth controllable switch and the tenth controllable switch are two independent controllable switches.

5. The scanning driving circuit according to claim 4, wherein a control terminal of the eleventh controllable switch receives a reset signal, an input terminal of the eleventh controllable switch is connected to the turn off electrical potential terminal, an output terminal of the eleventh controllable switch is connected to the ninth controllable switch, the tenth controllable switch and the scanning line.

6. The scanning driving circuit according to claim 5, wherein the first to the eleventh controllable switches are all N-type MOS transistors.

7. The scanning driving circuit according to claim 1, wherein the quantity of the driving units in the first driving circuit is the same with the quantity of the driving units in the second driving circuit and the touch scanning circuit is formed between the first driving circuit and the second driving circuit and two frame interval.

8. The scanning driving circuit according to claim 1, wherein the first driving circuit is set in the right-and-left sides of an upper portion of a liquid crystal display apparatus and a second driving circuit is set in the right-and-left sides of a lower portion of the liquid crystal display apparatus.

9. A liquid crystal display apparatus comprising the scanning driving circuit according to claim 1.