Display device and electronic apparatus

Patent metadata

Field	Value
Publication number	US-10991335-B2
Application number	US-201816765597-A
Country	US
Kind code	B2
Filing date	Oct 16, 2018
Priority date	Nov 28, 2017
Publication date	Apr 27, 2021
Grant date	Apr 27, 2021

Abstract

A display device according to the present disclosure includes: pixels arranged in a matrix; a data line group that includes a pair of data lines for each pixel column; a data line drive circuit that supplies a positive-phase data signal to one of the pair of data lines, and a negative-phase data signal to the other of the pair of data lines; and an auxiliary drive circuit that is provided for each pair of data lines, and that processes the positive-phase data signal and the negative-phase data signal, in which the auxiliary drive circuit has a dead zone in a region where there is no difference between a positive-phase potential and a negative-phase potential, or where the difference in potential is smaller than a predetermined value. An electronic apparatus according to the present disclosure includes a display device having the configuration described above.

First claim

What is claimed is:

1. A display device comprising:
a pixel array section that includes pixels arranged in a matrix;
a data line group that includes a pair of data lines provided for each pixel column;
a data line drive circuit that supplies a positive-phase data signal to one of the pair of data lines, and supplies a negative-phase data signal to another of the pair of data lines, the negative-phase data signal being opposite in phase to the positive-phase data signal; and
an auxiliary drive circuit that is provided for each pair of data lines, and processes the positive-phase data signal and the negative-phase data signal supplied from the data line drive circuit to the pair of data lines,
wherein the auxiliary drive circuit has a dead zone in a region where there is no difference between a positive-phase potential and a negative-phase potential, or where the difference in potential is smaller than a predetermined value.

2. The display device according to claim 1 , wherein
at least one auxiliary drive circuit is provided for each pair of data lines.

3. The display device according to claim 2 , wherein
the data line drive circuit is disposed on one end side of the data lines of the data line group, and
the auxiliary drive circuit is disposed at least on another end side of each data line of the data line group.

4. The display device according to claim 3 , wherein
the auxiliary drive circuit is disposed at an intermediate part between the one end and the another end of each data line of the data line group.

5. The display device according to claim 1 , wherein
the auxiliary drive circuit includes a positive-phase side circuit section for the positive-phase data signal and a negative-phase side circuit section for the negative-phase data signal.

6. The display device according to claim 5 , wherein
the positive-phase side circuit section and the negative-phase side circuit section each include a preceding-stage inverter circuit and a subsequent-stage inverter circuit, and
when VD>VXD, the auxiliary drive circuit detects a following condition in terms of a circuit, and operates to amplify a difference between a potential VD and a potential VXD:
VD>VXD+Vth _ b1 , or VD>VXD+Vth _ a2 ,

where VD is a potential of the data line to which the positive-phase data signal is supplied, VXD is a potential of the data line to which the negative-phase data signal is supplied, Vth_ a2 is a threshold value for a transistor included in the subsequent-stage inverter circuit of the positive-phase side circuit section, and Vth_ b1 is a threshold value for a transistor included in the preceding-stage inverter circuit of the negative-phase side circuit section.

7. The display device according to claim 6 , wherein
when VD<VXD, the auxiliary drive circuit detects a following condition in terms of a circuit, and operates to amplify the difference between the potential VD and the potential VXD:
VD<VXD−Vth _ a1 , or VD<VXD−Vth _ b2 ,

where Vth_ a1 is a threshold value for a transistor included in the preceding-stage inverter circuit of the positive-phase side circuit section, and Vth_ b2 is a threshold value for a transistor included in the subsequent-stage inverter circuit of the negative-phase side circuit section.

8. The display device according to claim 5 , wherein
the positive-phase side circuit section and the negative-phase side circuit section each include a preceding-stage inverter circuit to be driven by a first drive signal and a subsequent-stage inverter circuit to be driven by a second drive signal, and
when VD>VXD, the auxiliary drive circuit detects a following condition in terms of a circuit, and operates to amplify a difference between a potential VD and a potential VXD:
VD>VGP+Vth _ a2 , or VXD<VGN−Vth _ b1 ,

where VD is a potential of the data line to which the positive-phase data signal is supplied, VXD is a potential of the data line to which the negative-phase data signal is supplied, VGN is the first drive signal, VGP is the second drive signal, Vth_ a2 is a threshold value for a transistor included in the subsequent-stage inverter circuit of the positive-phase side circuit section, and Vth_ b1 is a threshold value for a transistor included in the preceding-stage inverter circuit of the negative-phase side circuit section.

9. The display device according to claim 8 , wherein
when VD<VXD, the auxiliary drive circuit detects a following condition in terms of a circuit, and operates to amplify the difference between the potential VD and the potential VXD:
VXD>VGP+Vth _ b2 , or VD<VGN−Vth _ a1 ,

where Vth_ a1 is a threshold value for a transistor included in the preceding-stage inverter circuit of the positive-phase side circuit section, and Vth_ b2 is a threshold value for a transistor included in the subsequent-stage inverter circuit of the negative-phase side circuit section.

10. The display device according to claim 5 , wherein
the auxiliary drive circuit uses a first power supply voltage and a second power supply voltage having a voltage value equal to or lower than ½ of the first power supply voltage,
the positive-phase side circuit section and the negative-phase side circuit section each include:
a NOR circuit that operates at the second power supply voltage, and receives the positive-phase data signal/negative-phase data signal and a predetermined drive signal as inputs; and
a level shift circuit that operates at the first power supply voltage, and shifts a high level of output of the NOR circuit from a level of the second power supply voltage to a level of the first power supply voltage, and
when VD>VXD, the auxiliary drive circuit starts to operate at a time point where a potential VD of the data line falls below a logic threshold of the NOR circuit of the positive-phase side circuit section.

11. The display device according to claim 10 , wherein
when VD<VXD, the auxiliary drive circuit starts to operate at a time point where a potential VXD of the data line falls below a logic threshold of the NOR circuit of the negative-phase side circuit section.

12. The display device according to claim 1 , further comprising:
a short circuit that is provided for each pair of data lines and selectively short-circuits the pair of data lines.

13. The display device according to claim 12 , wherein
the short circuit temporarily short-circuits the pair of data lines before the positive-phase data signal and the negative-phase data signal are supplied from the data line drive circuit to the pair of data lines, and releases the short circuit between the pair of data lines after setting a potential between the pair of data lines to an intermediate potential between the positive-phase potential and the negative-phase potential.

14. The display device according to claim 13 , wherein
before the short circuit short-circuits the pair of data lines, the data line drive circuit puts an output terminal corresponding to the pair of data lines in a high-impedance state, and supplies at least one of the positive-phase data signal or the negative-phase data signal to the pair of data lines after the short circuit releases the short circuit between the pair of data lines.

15. The display device according to claim 13 , wherein
the auxiliary drive circuit operates to hold the positive-phase data signal and the negative-phase data signal in synchronization with the short-circuit operation of the short circuit.

16. An electronic apparatus comprising:
a display device that includes:
a pixel array section that includes pixels arranged in a matrix;
a

Assignees

• Sony Semiconductor Solutions Corp

Inventors

• Orii Toshihiko
• Nakao Hiroshi
• Andou Naoki
• Takeda Kazuhiro
• Kawaguchi Keiko

Classifications

• H03K19/094

  using field-effect transistors · CPC title

• G09G2310/0248

  Precharge or discharge of column electrodes before or after applying exact column voltages · CPC title

• G09G3/3688 Primary

  suitable for active matrices only · CPC title

• G09G2310/021

  Double addressing, i.e. scanning two or more lines, e.g. lines 2 and 3; 4 and 5, at a time in a first field, followed by scanning two or more lines in another combination, e.g. lines 1 and 2; 3 and 4, in a second field · CPC title

• G09G2300/0857

  Static memory circuit, e.g. flip-flop · CPC title