Image display systems, shift registers and methods for controlling shift register
View Patent ↗An image display system includes a gate driving circuit and a data driving circuit. The gate driving circuit generates gate driving signals to drive pixels in a pixel array. The data driving circuit generates data driving signals to provide data to the pixels. At least one of the gate and data driving circuits includes a shift register. The shift register includes flip-flops coupled in serial. Each flip-flop generates output signals in response to an input signal, and is reset in response to a reset signal. One of the flip-flops receives a first output signal of a last stage flip-flop as the reset signal thereof, and at least one flip-flop following the flip-flop receiving the first output signal of the last stage flip-flop receives a second output signal of the flip-flop receiving the first output signal of the last stage flip-flop as the reset signal thereof.
1. An image display system, comprising:
a gate driving circuit, generating a plurality of gate driving signals to drive a plurality of pixels in a pixel array; and
a data driving circuit, generating a plurality of data driving signals to provide data to the pixels of the pixel array,
wherein at least one of the gate driving circuit and the data driving circuit comprises:
a shift register, comprising a plurality of flip-flops coupled in serial, wherein each flip-flop generates a plurality of output signals in response to an input signal, and is reset in response to a reset signal, wherein one of the flip-flops receives a first output signal of a last stage flip-flop as the reset signal thereof, and at least one flip-flop following the flip-flop receiving the first output signal of the last stage flip-flop receives a second output signal of the flip-flop receiving the first output signal of the last stage flip-flop as the reset signal thereof, and wherein more than one flip-flop following the flip-flop receiving the first output signal of the last stage flip-flop as the reset signal receive the second output signal of a same stage flip-flop as the reset signal thereof.
2. The image display system as claimed in claim 1 , further comprising a display panel, wherein the display panel comprises:
the gate driving circuit;
the data driving circuit;
the pixel array; and
a controller chip, for generating a start pulse,
wherein a first stage flip-flop of the shift register receives the start pulse as the input signal thereof, and each flip-flop following the first stage flip-flop receives the first output signal of a preceding flip-flop as the input signal thereof, and one or more flip-flop(s) preceding the flip-flop receiving the first output signal of the last stage flip-flop as the reset signal receive(s) the first output signal of a following flip-flop as the reset signal thereof.
3. The image display system as claimed in claim 1 , wherein one or more flip-flop(s) following the flip-flop receiving the first output signal of the last stage flip-flop as the reset signal receive(s) the second output signal of a preceding flip-flop as the reset signal thereof.
4. The image display system as claimed in claim 1 , further comprising:
a logic circuit, coupled to at least one feedback terminal, at which the reset signal of the corresponding flip-flop is received, and delaying the reset signal of the corresponding flip-flop.
5. The image display system as claimed in claim 1 , wherein at least one of the flip-flops comprises:
a latch circuit, receiving the input signal and the reset signal, and generating the second output signal of the flip-flop according to the input signal and the reset signal; and
a switch circuit, receiving a clock signal and outputting the clock signal as the first output signal of the flip-flop according to a level of the second output signal.
6. The image display system claimed in claim 5 , wherein the latch circuit comprises a plurality of logic gates for generating the second output signal according to a result of performing logic operation(s) on the input signal and the reset signal.
7. A shift register, comprising:
a plurality of flip-flops coupled in serial, wherein each flip-flop generates a plurality of output signals in response to an input signal, and is reset in response to a reset signal,
wherein an n-th stage flip-flop receives a first output signal of a last stage flip-flop as the reset signal thereof, and at least one flip-flop following the n-th stage flip-flop receives a second output signal of the n-th stage flip-flop as the reset signal thereof, wherein n is a positive integer, and wherein more than one flip-flop following the n-th stage flip-flop receive the second output signal of a same stage flip-flop as the reset signal thereof.
8. The shift register as claimed in claim 7 , wherein the first stage flip-flop receives a start pulse as the input signal thereof, and each flip-flop following the first stage flip-flop receives the first output signal of a preceding flip-flop as the input signal thereof, and one or more flip-flop(s) preceding the n-th stage flip-flop receive(s) the first output signal of a following flip-flop as the reset signal thereof.
9. The shift register as claimed in claim 7 , wherein one or more flip-flop(s) following the n-th stage flip-flop receive(s) the second output signal of a preceding flip-flop as the reset signal thereof.
10. The shift register as claimed in claim 7 , further comprising:
a logic circuit, coupled to at least one feedback terminal, at which the reset signal of the corresponding flip-flop is received, and delaying the reset signal of the corresponding flip-flop.
11. The shift register as claimed in claim 7 , wherein at least one of the flip-flops comprises:
a latch circuit, receiving the input signal and the reset signal, and generating the second output signal of the flip-flop according to the input signal and the reset signal; and
a switch circuit, receiving a clock signal and outputting the clock signal as the first output signal of the flip-flop according to a level of the second output signal.
12. The shift register as claimed in claim 11 , wherein the latch circuit comprises a plurality of logic gates for generating the second output signal according to a result of performing logic operation(s) on the input signal and the reset signal.
13. The shift register as claimed in claim 11 , wherein the first output signal is a result of performing logic operation(s) on the second output signal and the clock signal.
14. A shift register controlling method for controlling operations of a shift register comprising a plurality of flip-flops coupled in serial, wherein each flip-flop generates at least a first output signal and a second output signal in response to an input signal and is reset in response to a reset signal, the method comprises:
providing a start pulse to a first stage flip-flop as the input signal of the first stage flip-flop;
providing the first output signal of a preceding flip-flop as the input signal of each flip-flop following the first stage flip-flop;
providing the first output signal of a following flip-flop as the reset signal of each flip-flop preceding an n-th stage flip-flop, wherein n is a positive integer;
providing the first output signal of a last stage flip-flop as the reset signal of the n-th stage flip-flop;
providing the second output signal of the n-th stage flip-flop as the reset signal of at least one flip-flop following the n-th stage flip-flop; and
providing the second output signal of a same stage flip-flop as the reset signal of more than one flip-flop following the n-th stage flip-flop.
15. The method as claimed in claim 14 , wherein the first output signal of each flip-flop is a result of performing logic operation(s) on the second output signal of the flip-flop and a clock signal.
16. The method as claimed in claim 14 , further comprising:
providing the second output signal of a preceding flip-flop as the reset signal of one or more flip-flop(s) following the n-th stage flip-flop.
17. The method as claimed in claim 14 , further comprising:
delaying at least one reset signal of the flip-flops.