Shifting register depressing coupling effect and liquid crystal display

Abstract

The invention relates to a shift register used in liquid crystal display, whose output has low couple effect to provide better grid driving signal, wherein the output circuit of shift register has two switches; the control end of first switch is coupled to the control end of second switch; one end of first switch receives one clock signal, whose another end is coupled to one end of second switch; another end of second switch outputs one grid driving signal; and it uses one control signal to switch the first and second switches.

Description

technical field [0001] The invention relates to a shift register with lower coupling effects. More precisely, the invention relates to a shift register for a liquid crystal display with low coupling effects. Background technique [0002] Please refer to Figure 1. FIG. 1 is a schematic diagram of a conventional liquid crystal display 100 . The liquid crystal display 100 includes a pixel circuit 110 and a shift register area 120 . The pixel circuit 110 includes a plurality of pixels 111 . The shift register area 120 includes a plurality of shift registers S1-Sn, which are used to receive the voltage level signal VSS, clock signals XCK and CK, and the start signal ST transmitted from the outside, and transmit the gate drive according to the above signals. The signals G1-Gn are given to the pixel circuit 110 . The pixel circuit 110 respectively drives the included pixels 111 according to the gate driving signals G1 - Gn transmitted from the shift register 120 to display ima...

AI Technical Summary

Problems solved by technology

Because the switch Q8 in the output stage circuit 440 has a parasitic capacitance C1 between the node B and the node A, it will make the current from the node A flow to the node B, which will affect the switching action of the switch Q8, and cause the current in the switch Q8 The signal cannot be completely turned off when it is turned off, and there is a phenomenon of leakage current

That is to say, when the switch Q8 is in the off state, part of the clock signal CK still flows to the node C, which affects the gate driving signal Gn.

In the above-mentioned situation, after the switch Q8 has been used for a long time, the aging phenomenon will occur, and the shape will become more serious. As shown in Figure 5, the gate drive signal Gn will be poor when it is output, causing malfunction and reducing the quality of the display screen.

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