The present invention relates to a Thin Film Transistor Liquid Crystal Display (TFT-LCD) driving circuit.
A schematic structural diagram of a TFT-LCD driving circuit in the prior art is as shown in
A timing diagram for a TFT-LCD driving circuit in the prior art is as shown in
A timing diagram for another TFT-LCD driving circuit in the prior art is as shown in
Differences between
In the TFT-LCD driving circuit, generally, when the gate driving circuit outputs a gate driving signal for turning on a row of gate lines, a source driving circuit inputs data signals for respective pixels to which the row of gate lines correspond into respective pixel electrodes of the row. A schematic diagram of an ideal timing relationship between gate driving signals of a TFT-LCD and data signals input by a source driving circuit in the prior art is as shown in
For a Gate Driver on Array (GOA) panel, electrons in TFTs therein have a low moving speed, and the data confusion caused by the delays of the gate driving signals will be more severe.
An embodiment of the invention, in view of the above problems in the prior art, provides a TFT-LCD driving circuit which can avoid the confusion of data input into pixel electrodes caused by delays of gate driving signals.
The TFT-LCD driving circuit comprises input teiminals for inputting a CPV signal, an OE1 signal, an OE2 signal, and a STV signal, output terminals for outputting a CLK signal and a CLKB signal, and a processing circuit connected between the input terminals and the output terminals, for processing the CPV signal, the OE1 signal, the OE2 signal, and the STV signal, so that a set time interval exists between a falling edge of the output CLK signal and a rising edge of the CLKB signal in one cycle of the CLK signal, or that the set time interval exists between a rising edge of the output CLK signal and a falling edge of the CLKB signal in one cycle of the CLKB signal.
In the TFT-LCD driving circuit, the input terminals may include a CPV signal input terminal for inputting the CPV signal, an OE1 signal input terminal for inputting the OE1 signal, an OE2 signal input terminal for inputting the OE2 signal, and a STV signal input terminal for inputting the STV signal.
The output terminals may include a CLK signal output terminal for outputting the CLK signal, and a CLKB signal output terminal for outputting the CLKB signal.
The processing circuit may include a charge sharing control module and a control signal conversion module.
The charge sharing control module is connected to the input terminals, for receiving the CPV signal, the OE1 signal, the OE2 signal, and the STV signal, performing an OR processing on the OE1 signal and the OE2 signal, and performing a NOT processing on the STV signal.
The control signal conversion module is connected to the charge sharing control module and the output terminals respectively, for receiving a processing result of the charge sharing control module, and generating the CLK signal and the CLKB signal by a AND processing, a NOT processing, an NAND processing, and a time delay processing, wherein the set time interval exists between the falling edge of the CLK signal and the rising edge of the CLKB signal in one cycle of the CLK signal, or the set time interval exists between the rising edge of the CLK signal and the falling edge of the CLKB signal.
The processing circuit may also include a first OR gate, a first NOT gate, a first NAND gate, a first NOR gate, a second NOT gate, a third NOT gate, a fourth NOT gate, a fifth NOT gate, a D flip-flop, a first AND gate, a second AND gate, a third AND gate, and a second OR gate;
input terminals of the first OR gate are connected with the OE1 signal input terminal and the OE2 signal input terminal, respectively;
an input terminal of the first NOT gate is connected with the STV signal input terminal;
input terminals of the first NAND gate are connected with an output terminal of the first OR gate and an output terminal of the first NOT gate, respectively;
input terminals of the first NOR gate are connected to the CPV signal input terminal and an output terminal of the first NAND gate, respectively;
an input terminal of the second NOT gate is connected with the output terminal of the first OR gate;
an input terminal of the third NOT gate is connected with an output terminal of the first NOR gate;
a CP input terminal of the D flip-flop is connected with an output terminal of the third NOT gate;
an input terminal of the fourth NOT gate is connected with the STV signal input terminal, and an output terminal of the fourth NOT gate is connected with a CLRN input terminal of the D flip-flop;
an input terminal of the fifth NOT gate is connected with a Q output terminal of the D flip-flop, and an output terminal of the fifth NOT gate is connected with a D input terminal of the D flip-flop;
input terminals of the first AND gate are connected with an output terminal of the second NOT gate and the output terminal of the fifth NOT gate, respectively, and an output terminal of the first AND gate is connected with the CLK signal output terminal;
input terminals of the second AND gate are connected with the output terminal of the second NOT gate and the Q output terminal of the D flip-flop, respectively;
input terminals of the third AND gate are connected with the STV signal input terminal and the output terminal of the first NOR gate, respectively;
input terminals of the second OR gate are connected with an output terminal of the second AND gate and an output terminal of the third AND gate, respectively, and an output terminal of the second OR gate is connected with the CLKB signal output terminal.
Based on the above technical solution, the TFT-LCD driving circuit may further comprise an amplifying circuit;
the output terminals for outputting the CLK signal and CLKB signal may further include a STVP signal output terminal for outputting a STV signal and an amplified OE2 signal output terminal for outputting an amplified OE2 signal;
the output terminal of the first AND gate and the CLK signal output terminal are both connected with the amplifying circuit;
the output terminal of the second OR gate and the CLKB signal output terminal are both connected with the amplifying circuit;
the STV signal output terminal and the STVP signal output terminal are both connected with the amplifying circuit; and
the OE2 signal input terminal and the amplified OE2 signal output terminal are both connected with the amplifying circuit.
The TFT-LCD circuit provided by the embodiment of the invention may generate the CLK signal and the CLKB signal from the STV signal, the OE1 signal, the OE2 signal, and the CPV signal in the prior art, and for the CLK signal and the CLKB signal generated by the circuit, the falling edge of the CLK signal and the rising edge of the CLKB signal may be staggered by a certain time interval in one cycle of the CLK signal, or the falling edge of the CLKB signal and the rising edge of the CLK signal may be staggered by the certain time interval in one cycle of the CLKB signal, so that the confusion of data input to pixel electrodes caused by delays of gate driving signals may be avoided.
Hereinafter, a further description of technical solutions of the invention will be made in detail with reference to attached drawings and embodiments.
a shows a timing diagram of a TFT-LCD driving circuit in the prior art;
b shows a timing diagram of another TFT-LCD driving circuit in the prior art;
a shows a timing diagram of a TFT-LCD driving circuit of the embodiment of the invention; and
b shows another timing diagram of a TFT-LCD driving circuit of the embodiment of the invention.
An embodiment of the invention provides a TFT-LCD driving circuit, comprising input terminals for inputting a CPV signal, an OE1 signal, an OE2 signal, and a STV signal, output terminals for outputting a CLK signal and a CLKB signal, and a processing circuit connected between the input terminals and the output terminals, for processing the CPV signal, the OE1 signal, the OE2 signal, and the STV signal, so that a set time interval exists between a falling edge of the output CLK signal and a rising edge of the CLKB signal in one cycle of the CLK signal, or that a set time interval exists between a rising edge of the output CLK signal and a falling edge of the CLKB signal in one cycle of the CLKB signal.
In the TFT-LCD driving circuit, input terminals may include a CPV signal input terminal for inputting the CPV signal, an OE1 signal input terminal for inputting the OE1 signal, an OE2 signal input terminal for inputting the OE2 signal, and a STV signal input terminal for inputting the STV signal.
The output terminals may include a CLK signal output terminal for outputting the CLK signal, and a CLKB signal output terminal for outputting the CLKB signal.
The processing circuit may include a charge sharing control module and a control signal conversion module.
The charge sharing control module is connected to the input terminals, for receiving the CPV signal, the OE1 signal, the OE2 signal, and the STV signal, performing an OR processing on the OE1 signal and the OE2 signal, and performing a NOT processing on the STV signal.
The control signal conversion module is connected to the charge sharing control module and the output terminals respectively, for receiving a processing result of the charge sharing control module, and generating the CLK signal and the CLKB signal by a AND processing, a NOT processing, an NAND processing, and a time delay processing, wherein the set time interval exists between the falling edge of the CLK signal and the rising edge of the CLKB signal in one cycle of the CLK signal, or the set time interval exists between the rising edge of the CLK signal and the falling edge of the CLKB signal in one cycle of the CLKB signal.
A schematic structural diagram of a TFT-LCD driving circuit according to a first embodiment of the invention is as shown in
A processing circuit DRIV includes a first OR gate OR1, a first NOT gate N1, a first NAND gate NAND1, a first NOR gate NOR1, a second NOT gate N2, a third NOT gate N3, a fourth NOT gate N4, a fifth NOT gate N5, a D flip-flop D1, a first AND gate AND1, a second AND gate AND2, a third AND gate AND3, and a second OR gate OR2;
input terminals of the first OR gate OR1 are connected with the OE1 signal input terminal and the OE2 signal input terminal, respectively;
an input terminal of the first NOT gate N1 is connected with the STV signal input terminal;
input terminals of the first NAND gate NAND1 are connected with an output terminal of the first OR gate OR1 and an output terminal of the first NOT gate N1, respectively;
input terminals of the first NOR gate NOR1 are connected to the CPV signal input terminal and an output terminal of the first NAND gate AND1, respectively;
an input terminal of the second NOT gate N2 is connected with the output terminal of the first OR gate OR1;
an input terminal of the third NOT gate N3 is connected with an output terminal of the first NOR gate NOR1;
a CP input terminal of the D flip-flop D1 is connected with an output terminal of the third NOT gate N3;
an input terminal of the fourth NOT gate N4 is connected with the STV signal input terminal, and an output terminal of the fourth NOT gate N4 is connected with a CLRN input terminal of the D flip-flop D1;
an input terminal of the fifth NOT gate N5 is connected with a Q output terminal of the D flip-flop D1, and an output terminal of the fifth NOT gate N5 is connected with a D input terminal of the D flip-flop D1;
input terminals of the first AND gate AND1 are connected with an output terminal of the second NOT gate N2 and the output terminal of the fifth NOT gate N5, respectively, and an output terminal of the first AND gate AND1 is connected with the CLK signal output terminal;
input terminals of the second AND gate AND2 are connected with the output terminal of the second NOT gate N2 and the Q output terminal of the D flip-flop D1, respectively;
input terminals of the third AND gate AND3 are connected with the STV signal input terminal A4 and the output terminal of the first NOR gate N1, respectively; and
input terminals of the second OR gate OR2 are connected with an output terminal of the second AND gate AND2 and an output terminal of the third AND gate AND3, respectively, and an output terminal of the second OR gate OR2 is connected with the CLKB signal output terminal.
The CLRN input terminal, the PRN input terminal, the CP input terminal, the D input terminal, and the Q output terminal of the D flip-flop D1 in
Operating principles of the TFT-LCD driving circuit of the embodiment of the invention will be illustrated below.
In
A schematic structural diagram of a TFT-LCD driving circuit according to a second embodiment of the invention is as shown in
In the second embodiment, the amplifying circuit amplifies the generated CLK signal and CLKB signal, and amplifies the STV signal and the OE2 signal input from the processing circuit, so that levels of the respective signals may meet requirements of the GOA panel.
Further, the charge shared control module involved in the aforesaid embodiment may include the first OR gate OR1 and the first NOT gate N1 in the embodiment as shown in
A timing diagram of the TFT-LCD driving circuit of the embodiment of the invention is as shown in
In the timing diagram shown in
The TFT-LCD circuit provided by the embodiment of the invention may generate the CLK signal and the CLKB signal from the STV signal, the OE1 signal, the OE2 signal, and the CPV signal in the prior art, and for the CLK signal and the CLKB signal generated by the circuit, the falling edge of the CLK signal and the rising edge of the CLKB signal may be staggered by a certain time interval in one cycle of the CLK signal, or the falling edge of the CLKB signal and the rising edge of the CLK signal may be staggered by the certain time interval in one cycle of the CLKB signal, so that confusion of data input to pixel electrodes due to delays of gate driving signals may be avoided.
Finally, it is to be explained that the above embodiments are only used to illustrate, instead of limiting, technical solutions of the invention; although the invention is illustrated in detail with reference to embodiments thereof, it is to be understood by those of ordinary skill in the art that modifications or equivalent substitutions may still be made to the technical solutions of the invention, without departing the sprite and scope of the technical solution of the invention
Number | Date | Country | Kind |
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200910093017.5 | Sep 2009 | CN | national |