DISPLAY DEVICE

• US 20080211800A1
• Filed: 12/26/2007
• Published: 09/04/2008
• Est. Priority Date: 12/27/2006
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: MIYAKE, Hiroyuki, ARASAWA, Ryo
• Granted Patent: US 8,643,635 B2
• Time in Patent Office: Days
• US Class Current: 345/211
• CPC Class Codes: G09G 2300/0857 Static memory circuit, e.g. flip-flop
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• CPC Class Codes: G09G 2330/028 Generation of voltages supplied to electrode drivers in a matrix display other than LCD
• CPC Class Codes: G09G 3/20 for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
• CPC Class Codes: G09G 3/3258 with pixel circuitry controlling the voltage across the light-emitting element
• CPC Class Codes: G09G 5/00 Control arrangements or circuits for visual indicators common to cathode-ray tube indicators and other visual indicators image data processing or generation, in general G06T

Abstract

A display device is driven through no wire cable such as an FPC, and a display image is continuously held for a certain period of time by storing an image signal received from a wireless communication device so that the display image can be held even when the display device is out of communication range with the wireless communication device. A display device includes at least a pixel circuit having an SRAM (static random access memory) circuit, a circuit which controls the pixel circuit, an antenna circuit, a circuit which generates a demodulation signal, a circuit which rectifies a wireless signal, a circuit which generates first voltage, a charge circuit which stores second voltage, a charge control circuit, a voltage supply control circuit, and a circuit which controls the charge control circuit and the voltage supply control circuit.

Claims

1. A display device comprising:

a display portion;

a pixel circuit in the display portion, the pixel circuit including an SRAM circuit;

a first circuit configured to control the pixel circuit;

an antenna circuit;

a second circuit configured to generate a demodulation signal from a wireless signal received by the antenna circuit;

a third circuit configured to rectify the wireless signal received by the antenna circuit;

a fourth circuit configured to generate a first voltage from a voltage rectified in the third circuit;

a charge circuit configured to store a second voltage from a voltage rectified in the third circuit;

a charge control circuit configured to control charging of the second voltage to the charge circuit;

a voltage supply control circuit;

a fifth circuit configured to control the charge control circuit and the voltage supply control circuit; and

a sixth circuit configured to select one of the first voltage and the second voltage,

wherein the voltage supply control circuit is configured to supply the second voltage to the sixth circuit.

2. The display device according to claim 1, wherein the third circuit is electrically connected to both the fourth circuit and the fifth circuit.

3. The display device according to claim 1, wherein the second circuit includes a first demodulation circuit and a second demodulation circuit, and the first demodulation circuit is configured to supply the demodulation signal generated in the first demodulation circuit to the first circuit, and the second demodulation circuit is configured to supply the demodulation signal generated in the second demodulation circuit to the charge control circuit.

4. The display device according to claim 1, wherein voltage selected in the sixth circuit is supplied to the first circuit.

5. The display device according to claim 1, wherein the fifth circuit includes a voltage comparison circuit.

6. The display device according to claim 1, wherein the fifth circuit includes a counter circuit.

7. A display device comprising:

a display portion;

a pixel circuit in the display portion, the pixel circuit including an SRAM circuit;

a first circuit configured to control the pixel circuit;

a first antenna circuit;

a second antenna circuit;

a second circuit configured to generate a demodulation signal from a wireless signal received by the first antenna circuit;

a third circuit configured to rectify the wireless signal received by the first antenna circuit;

a fourth circuit configured to rectify the wireless signal received by the second antenna circuit;

a fifth circuit configured to generate first voltage from voltage rectified in the third circuit;

a sixth circuit configured to generate a demodulation signal from a wireless signal received by the second antenna circuit;

a charge circuit configured to store second voltage from voltage generated in the fourth circuit;

a charge control circuit configured to control charging of the second voltage to the charge circuit;

a voltage supply control circuit;

a seventh circuit configured to control the charge control circuit and the voltage supply control circuit; and

an eighth circuit configured to select one of the first voltage and the second voltage,

wherein the voltage supply control circuit is configured to supply the second voltage to the eighth circuit.

8. The display device according to claim 7, wherein the second antenna circuit has a different shape from the first antenna circuit.

9. The display device according to claim 7, wherein the voltage generated from the third circuit is supplied to the fifth circuit, and the voltage generated from the fourth circuit is supplied to the seventh circuit.

10. The display device according to claim 7, wherein the seventh circuit includes a voltage comparison circuit.

11. The display device according to claim 7, wherein the seventh circuit includes a counter circuit.

12. A display device comprising:

a pixel circuit having an SRAM circuit formed over a substrate;

an antenna circuit formed over the substrate;

a signal processing circuit formed over the substrate; and

a power generation portion formed over the substrate.

13. The display device according to claim 12, wherein the power generation portion comprising a constant voltage circuit and a charge circuit.