Display device and driving apparatus thereof

• US 20060138983A1
• Filed: 12/21/2005
• Published: 06/29/2006
• Est. Priority Date: 12/23/2004
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Lee, Joo-Hyung, Uh, Kee-Han, Choi, Young-Jun
• Granted Patent: US 7,973,777 B2
• Time in Patent Office: Days
• US Class Current: 349/56
• CPC Class Codes: G06F 1/3215 Monitoring of peripheral devices
• CPC Class Codes: G06F 1/324 by lowering clock frequency
• CPC Class Codes: G06F 1/3287 by switching off individual functional units in the computer system
• CPC Class Codes: G06F 2203/04106 Multi-sensing digitiser, i.e. digitiser using at least two different sensing technologies simultaneously or alternatively, e.g. for detecting pen and finger, for saving power or for improving position detection
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/042 by opto-electronic means
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management
• CPC Class Codes: Y02D 30/50 in wire-line communication networks, e.g. low power modes or reduced link rate

Abstract

A display apparatus may include touch detection circuitry including a light sensing circuit and a physical parameter sensing circuit (e.g., a pressure sensing circuit). The display apparatus may further include processing circuitry implementing a power-saving mode and a normal mode, and configured to generate touch information. An display driver may include a photo sensing circuit and a pressure sensing circuit. An embodiment of the display driver may include: an amplifying unit amplifying a photo sensing signal and a pressure sensing signal; a parallel-to-serial converting unit converting the amplified photo sensing signal and the amplified pressure sensing signal into serial sensing signals; and an analog-to-digital converter converting the serial sensing signals into digital sensing signals, wherein the amplifying unit, the parallel-to-serial converting unit, and the analog-to-digital converter operate in one of a normal mode and a power saving mode according to the pressure sensing signal.

Claims

1. An apparatus to drive a display device including a photo sensing circuit and a pressure sensing circuit, the apparatus comprising:

an amplifying unit configured to amplify a photo sensing signal from the photo sensing circuit and a pressure sensing signal from the pressure sensing circuit;

a parallel-to-serial converting unit configured to convert the amplified photo sensing signal and the amplified pressure sensing signal into serial sensing signals; and

an analog-to-digital converter configured to convert the serial sensing signals into digital sensing signals,

wherein the amplifying unit, the parallel-to-serial converting unit, and the analog-to-digital converter are configured to operate in one of a normal mode and a power saving mode based on the pressure sensing signal.

2. The apparatus of claim 1, wherein the amplifying unit comprises:

a first amplifier configured to amplify the photo sensing signal, and wherein the apparatus is configured so power is not supplied to the first amplifier in the power saving mode; and

a second amplifier configured to amplify the pressure sensing signal.

3. The apparatus of claim 2, further comprising:

a first sample and holder connected between the first amplifier and the parallel-to-serial converting unit, the first sample and holder configured to sample-and-hold the amplified photo sensing signal, wherein the apparatus is configured so power is not supplied to the first sample and holder in the power saving mode; and

a second sample and holder connected between the second amplifier and the parallel-to-serial converting unit, the second sample and holder configured to sample and hold the amplified pressure sensing signal.

4. The apparatus of claim 1, wherein the parallel-to-serial converting unit comprises:

a first parallel-to-serial converter configured to operate in the normal mode; and

a second parallel-to-serial converter configured to operate in the power saving mode.

5. The apparatus of claim 4, wherein the first parallel-to-serial converter is configured to convert the amplified photo sensing signal and the amplified pressure sensing signal into first serial sensing signals in synchronization with a first clock signal, and

the second parallel-to-serial converter is configured to convert the amplified pressure sensing signal into a second serial sensing signal in synchronization with a second clock signal having a frequency lower than the first clock signal.

6. The apparatus of claim 5, further comprising a switch configured to select one of the first parallel-to-serial converter and the second parallel-to-serial converter.

7. The apparatus of claim 4, wherein the system is configured so that power is not supplied to the first parallel-to-serial converter during the power saving mode, and so that power is not supplied to the second parallel-to-serial converter during the normal mode.

8. The apparatus of claim 1, wherein the analog-to-digital converter is configured to operate in synchronization with a first clock signal during the normal mode, and is configured to operate in synchronization with a second clock signal having a frequency lower than the first clock signal during the power saving mode.

9. The apparatus of claim 1, wherein the apparatus is configured to operate in the normal mode when it is determined from the pressure sensing signal that a touch exists, and the apparatus is configured to operate in the power saving mode when it is determined from the pressure sensing signal that there is no touch for a predetermined time.

10. An apparatus to drive a display device including a photo sensing circuit and a pressure sensing circuit, the apparatus comprising:

a first amplifier configured to amplify a photo sensing signal from the photo sensing circuit;

a second amplifier configured to amplify a pressure sensing signal from the pressure sensing circuit;

a parallel-to-serial converter configured to convert the amplified photo sensing signal and the amplified pressure sensing signal into serial sensing signals; and

an analog-to-digital converter configured to convert the serial sensing signals into digital sensing signals,

wherein the apparatus is configured to selectively block the first amplifier from power supply based on the pressure sensing signal.

11. The apparatus of claim 10, further comprising:

a first sample and holder connected between the first amplifier and the parallel-to-serial converter and configured to sample-and-hold the amplified photo sensing signal, the apparatus configured to selectively block the first sample and holder from power supply based on the pressure sensing signal; and

a second sample and holder connected between the second amplifier and the parallel-to-serial converting unit and configured to sample-and-hold the amplified pressure sensing signal.

12. The apparatus of claim 10, wherein the parallel-to-serial converter and the analog-to-digital converter are configured to operate in synchronization with a selected one of a first clock signal and a second clock signal having a frequency lower than the first clock, and the selection of one of the first and the second clock signals is based on the pressure sensing signal.

13. An apparatus to drive a display device including a photo sensing circuit and a pressure sensing circuit, the apparatus comprising:

an amplifier configured to amplify a photo sensing signal from the photo sensing circuit and a pressure sensing signal from the pressure sensing circuit;

a parallel-to-serial converting unit configured to convert the amplified photo sensing signal and the amplified pressure sensing signal into serial sensing signals; and

an analog-to-digital converter configured to convert the serial sensing signals into digital sensing signals,

wherein the parallel-to-serial converting unit and the analog-to-digital converter are configured to operate in synchronization with a selected one of a first clock signal and a second clock signal having a frequency lower than the first clock signal, and the selection of one of the first and the second clock signals is based on the pressure sensing signal.

14. The apparatus of claim 13, wherein the parallel-to-serial converting unit comprises:

a first parallel-to-serial converter configured to operate in synchronization with the first clock signal; and

a second parallel-to-serial converter configured to operate in synchronization with the second clock signal.

15. The apparatus of claim 14, wherein the first parallel-to-serial converter is configured to convert the amplified photo sensing signal and the amplified pressure sensing signal into first serial sensing signals, and the second parallel-to-serial converter is configured to convert the amplified pressure sensing signal into a second serial sensing signal.

16. The apparatus of claim 14, further comprising a switch configured to select one of the first parallel-to-serial converter and the second parallel-to-serial converter based on the pressure sensing signal.

17. A display device comprising:

a plurality of display circuits;

a plurality of photo sensing circuits;

a plurality of pressure sensing circuits;

a plurality of sensor data lines connected to the photo sensing circuits and the pressure sensing circuits;

an image data driver configured to convert image signals into data voltages and configured to apply the data voltages to the display circuits;

a sensing signal processor configured to process photo sensor data signals supplied from the photo sensing circuits and pressure sensor data signals supplied from the pressure sensing circuits, and configured to operate in one of a normal mode and a power saving mode based on the pressure sensor data signals; and

a signal controller configured to receive the image signals from an external device and to control the image data driver and the sensing signal processor.

18. The display device of claim 17, wherein the sensing signal processor comprises:

a first amplifier configured to amplify the photo sensing signals;

a second amplifier configured to amplify the pressure sensing signals;

a first parallel-to-serial converter configured to convert the amplified photo sensing signals and the amplified pressure sensing signals into first serial sensing signals;

a second parallel-to-serial converter configured to convert the amplified pressure sensing signals into second serial sensing signals; and

an analog-to-digital converter configured to convert the first and the second serial sensing signals into digital sensing signals.

19. The display device of claim 18, wherein the device is configured so the first amplifier is not supplied power during the power saving mode.

20. The display device of claim 18, wherein the first parallel-to-serial converter is configured to operate during the normal mode, and the second parallel-to-serial converter is configured to operate during the power saving mode.

21. The display device of claim 20, wherein the first parallel-to-serial converter is configured to operate in synchronization with a first clock signal, and the second parallel-to-serial converter is configured to operate in synchronization with a second clock signal having a frequency lower than the first clock signal.

22. The display device of claim 20, wherein the device is configured so that the first parallel-to-serial converter is not supplied power during the power saving mode, and the second parallel-to-serial converter is not supplied power during the normal mode.

23. The display device of claim 18, wherein the analog-to-digital converter is configured to operate in synchronization with a first clock signal during the normal mode, and is configured to operate in synchronization with a second clock signal having a frequency lower than the first clock signal during the power saving mode.

24. The display device of claim 17, wherein the image data driver, the sensing signal processor, and the signal controller are integrated in a single integrated circuit chip.

25. A method of driving a display device including a photo sensing circuit and a pressure sensing circuit, the method comprising:

processing a first pressure sensing signal output from the pressure sensing circuit;

determining whether a touch exists based on the first pressure sensing signal;

if it is determined from the first pressure signal that there is a touch, processing a photo sensing signal outputted from the photo sensing circuit and a second pressure sensing signal outputted from the pressure sensing circuit;

determining whether a touch exists based on the second pressure sensing signal; and

when it is determined from the second pressure signal that there is no touch for a predetermined time, processing the first pressure sensing signal output from the pressure sensing circuit.

26. The method of claim 25, wherein when it is determined from the first pressure signal that there is no touch, the processing of the first pressure sensing signal is continued, and

when it is determined from the second pressure signal that there is a touch and an elapsed time is shorter than the predetermined time, the processing of the photo sensing signal and a second pressure sensing signal is continued.

27. The method of claim 26, wherein the display device further comprises an amplifier amplifying the photo sensing signal, and

wherein the processing of the first pressure sensing signal comprises:

blocking power from being applied to the amplifier.

28. The method of claim 26, wherein the display device further comprises a parallel-to-serial converter converting the photo sensing signal and the first and the second pressure sensing signals into serial sensing signals and an analog-to-digital converter converting the serial sensing signals into digital sensing signals;

wherein the processing of the first pressure sensing signal comprises;

driving the parallel-to-serial converter and the analog-to-digital converter to operate in synchronization with a first clock signal; and

wherein the processing of the photo sensing signal and a second pressure sensing signal comprises;

driving the parallel-to-serial converter and the analog-to-digital converter to operate in synchronization with a second clock signal having a frequency higher than the first clock signal.

29. The method of claim 26, wherein the display device further comprises a first parallel-to-serial converter converting the photo sensing signal and the second pressure sensing signal into serial signals and a second parallel-to-serial converter converting the first pressure sensing signal into a serial signal;

wherein the processing of the first pressure sensing signal comprises;

blocking power from being applied to the first parallel-to-serial converter; and

wherein the processing of a photo sensing signal and a second pressure sensing signal comprises;

blocking power from being applied to the second parallel-to-serial converter.

30. A display apparatus comprising:

touch detection circuitry comprising;

a light sensing circuit configured to generate a signal indicative of sensed light; and

a physical parameter sensing circuit configured to generate a signal indicative of a sensed physical parameter;

processing circuitry configured to generate touch information indicative of at least one of detection information and position information of a touch, wherein the processing circuitry implements a power-saving mode and a normal mode; and

wherein the processing circuitry is configured to generate the touch information based on the signal indicative of the sensed physical parameter and not based on the signal indicative of sensed light in the power saving mode.

31. The apparatus of claim 30, wherein the processing circuitry is configured to generate the touch information based on the signal indicative of the sensed physical parameter and based on the signal indicative of sensed light in the normal mode.

32. The apparatus of claim 30, wherein the physical parameter sensing circuit is a pressure sensing circuit.