Display device and driving apparatus including a photo sensing circuit and a pressure sensing circuit and method thereof

• US 7,973,777 B2
• Filed: 12/21/2005
• Issued: 07/05/2011
• 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: Uh, Kee-Han, Choi, Young-Jun, Lee, Joo-Hyung
• Primary Examiner(s): Nguyen; Chanh
• Assistant Examiner(s): BLANCHA, JONATHAN M
• Application Number:
  US11/315,088
• Publication Number:
  US 20060138983A1
• Time in Patent Office: 2,022 Days
• Field of Search: 345/204, 345173-178, 713/324
• US Class Current: 345/175
• 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 panel including a photo sensing circuit and a pressure sensing circuit, the apparatus comprising:

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

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

a first parallel-to-serial converter coupled with the first amplifier and selectively coupled with the second amplifier;

a second parallel-to-serial converter selectively coupled with the second amplifier; and

an analog-to-digital converter coupled with the first parallel-to-serial converter and the second parallel-to-serial converter,

wherein the first and second amplifier, the first and second parallel-to-serial converter, 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, and

wherein the pressure sensing circuit senses a pressure by closing a switch under a pressure initiated by a touch exerted on a surface of the display panel, and

when in the normal mode,

the first amplifier amplifies the photo sensing signal,

the second amplifier amplifies the pressure sensing signal,

the first parallel-to-serial converter is coupled with the first amplifier and the second amplifier, and converts the amplified photo sensing signal and the amplified pressure sensing signal into first serial sensing signals, and

the analog-to-digital converter converts the first serial sensing signals into first digital sensing signals, and

when in the power saving mode,

the first amplifier is not provided with power,

the second amplifier amplifies the pressure sensing signal,

the second parallel-to serial converter is coupled with the second amplifier, and converts the amplified pressure sensing signal into a second serial sensing signal, and

the analog-to-digital converter converts the second serial sensing signal into a second digital sensing signal.

2. The apparatus of claim 1, further comprising:

a first sample and holder connected between the first amplifier and the first parallel-to-serial converter, 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 first parallel-to-serial converter in the normal mode, the second sample and holder connected between the second amplifier and the second parallel-to-serial converter in the power saving mode, and the second sample and holder configured to sample and hold the amplified pressure sensing signal.

3. The apparatus of claim 1, 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.

4. The apparatus of claim 3, further comprising a switch configured to select one of the first parallel-to-serial converter and the second parallel-to-serial converter.

5. The apparatus of claim 1, 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.

6. 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.

7. 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.

8. The apparatus of claim 1, wherein the apparatus to drive the display device identifies a position of the touch, only if touching the display panel in substance.

9. The apparatus of claim 1, wherein the first parallel-to-serial converter is configured to convert the photo sensing signal and the pressure sensing signal into serial sensing signals in the normal mode and the second parallel-to-serial converter is configured to convert the pressure sensing signal into serial sensing signals in the power saving mode.

10. The apparatus of claim 9, wherein serial sensing signals through the first parallel-to-serial converter identify an existence of the touch and the position of the touch and serial sensing signals through the second parallel-to-serial converter identify only the existence of the touch in the normal mode.

11. 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 be inputted a photo sensing signal from the photo sensing circuit;

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

a first parallel-to-serial converter coupled with the first amplifier and selectively coupled with the second amplifier;

a second parallel-to-serial converter selectively coupled with the second amplifier; and

an analog-to-digital converter coupled with the first parallel-to-serial converter and the second parallel-to-serial converter,

wherein the apparatus is configured to operate in one of a normal mode and a power saving mode based on the pressure sensing signal, and

when in the normal mode,

the first amplifier amplifies the photo sensing signal,

the second amplifier amplifies the pressure sensing signal,

the first parallel-to-serial converter is coupled with the first amplifier and the second amplifier, and converts the amplified photo sensing signal and the amplified pressure sensing signal into first serial sensing signals, and

the analog-to-digital converter converts the first serial sensing signals into first digital sensing signals, and

when in the power saving mode,

the first amplifier is not provided with power,

the second amplifier amplifies the pressure sensing signal,

the second parallel-to serial converter is coupled with the second amplifier, and converts the amplified pressure sensing signal into a second serial sensing signal, and

the analog-to-digital converter converts the second serial sensing signal into a second digital sensing signal.

12. The apparatus of claim 11, further comprising:

a first sample and holder connected between the first amplifier and the first 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 first parallel-to-serial converter in the normal mode, the second sample and holder connected between the second amplifier and the second parallel-to-serial converter in the power saving mode, and the second sample and holder configured to sample-and-hold the amplified pressure sensing signal.

13. The apparatus of claim 11, wherein the analog-to-digital converter is 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.

14. The apparatus of claim 11, wherein serial sensing signals through the first parallel-to-serial converter identify an existence of the touch and the position of the touch and serial sensing signals through the second parallel-to-serial converter identify only the existence of the touch in the normal mode.

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

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

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

a first parallel-to-serial converter coupled with the first amplifier and selectively coupled with the second amplifier;

a second parallel-to-serial converter selectively coupled with the second amplifier; and

an analog-to-digital converter coupled with the first parallel-to-serial converter and the second parallel-to-serial converter,

wherein, when in the normal mode,

the first amplifier amplifies the photo sensing signal,

the second amplifier amplifies the pressure sensing signal,

the first parallel-to-serial converter is coupled with the first amplifier and the second amplifier, and converts the amplified photo sensing signal and the amplified pressure sensing signal into first serial sensing signals, and

the analog-to-digital converter converts the first serial sensing signals into first digital sensing signals, and

when in the power saving mode,

the first amplifier is not provided with power,

the second amplifier amplifies the pressure sensing signal,

the second parallel-to serial converter is coupled with the second amplifier, and converts the amplified pressure sensing signal into a second serial sensing signal, and

the analog-to-digital converter converts the second serial sensing signal into a second digital sensing signal, and

wherein the analog-to-digital converter is 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,

wherein the pressure sensing circuit senses a pressure by closing a switch under a pressure initiated by a touch exerted on a surface of the display panel.

16. The apparatus of claim 15, wherein the first parallel-to-serial converter is configured to operate in synchronization with the first clock signal and

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

17. The apparatus of claim 15, 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.

18. A display device comprising a display panel assembly which comprises:

a display panel which comprises a plurality of pixels which include;

a plurality of photo sensing circuits,

a plurality of pressure sensing circuits, and

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 panel assembly;

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,

wherein the pressure sensing circuit senses a pressure by closing a switch under a pressure initiated by a touch exerted on a surface of the display panel assembly, and

wherein the sensing signal processor receives the photo sensing signal and the pressure sensing signal in the normal mode and receives the pressure sensing signal in the power saving mode,

wherein the sensing signal processor comprises;

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

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

a first parallel-to-serial converter coupled with the first amplifier and selectively coupled with the second amplifier;

a second parallel-to-serial converter selectively coupled with the second amplifier; and

an analog-to-digital converter coupled with the first parallel-to-serial converter and the second parallel-to-serial converter,

when in the normal mode,

the first amplifier amplifies the photo sensing signal,

the second amplifier amplifies the pressure sensing signal,

the first parallel-to-serial converter is coupled with the first amplifier and the second amplifier, and converts the amplified photo sensing signal and the amplified pressure sensing signal into first serial sensing signals, and

the analog-to-digital converter converts the first serial sensing signals into first digital sensing signals, and

when in the power saving mode,

the first amplifier is not provided with power,

the second amplifier amplifies the pressure sensing signal,

the second parallel-to serial converter is coupled with the second amplifier, and converts the amplified pressure sensing signal into a second serial sensing signal, and

the analog-to-digital converter converts the second serial sensing signal into a second digital sensing signal.

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 apparatus of claim 20, wherein the first parallel-to-serial converter is configured to convert the photo sensing signal and the pressure sensing signal into serial sensing signals in the normal mode and the second parallel-to-serial converter is configured to convert the pressure sensing signal into serial sensing signals in the power saving mode.

24. The apparatus of claim 23, wherein serial sensing signals through the first parallel-to-serial converter identify an existence of the touch and the position of the touch and serial sensing signals through the second parallel-to-serial converter identify only the existence of the touch in the normal mode.

25. 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.

26. The display device of claim 18, wherein the image data driver, the sensing signal processor, and the signal controller are integrated in a single integrated circuit chip.

27. The apparatus of claim 18, wherein the apparatus to drive the display panel identifies a position of the touch, only if touching the display panel in substance.

28. A method of driving a display panel 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 together in a normal mode;

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 in a power saving mode,

wherein the pressure sensing circuit senses a pressure by closing a switch under a pressure initiated by a touch exerted on a surface of the display panel, and

wherein the display panel further comprises;

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

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

a first parallel-to-serial converter coupled with the first amplifier and selectively coupled with the second amplifier;

a second parallel-to-serial converter selectively coupled with the second amplifier; and

an analog-to-digital converter coupled with the first parallel-to-serial converter and the second parallel-to-serial converter,

when in the normal mode,

the first amplifier amplifies the photo sensing signal,

the second amplifier amplifies the pressure sensing signal,

the first parallel-to-serial converter is coupled with the first amplifier and the second amplifier, and converts the amplified photo sensing signal and the amplified pressure sensing signal into first serial sensing signals, and

the analog-to-digital converter converts the first serial sensing signals into first digital sensing signals, and

when in the power saving mode,

the first amplifier is not provided with power,

the second amplifier amplifies the pressure sensing signal,

the second parallel-to serial converter is coupled with the second amplifier, and converts the amplified pressure sensing signal into a second serial sensing signal, and

the analog-to-digital converter converts the second serial sensing signal into a second digital sensing signal.

29. The method of claim 28, 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.

30. The method of claim 29,

wherein the processing of the first pressure sensing signal comprises:

blocking power from being applied to the amplifier.

31. The method of claim 29, 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.

32. The method of claim 29, 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.

33. The method of claim 32, wherein the first parallel-to-serial converter is configured to convert the photo sensing signal and the pressure sensing signal into serial sensing signals in the normal mode and the second parallel-to-serial converter is configured to convert the pressure sensing signal into serial sensing signals in the power saving mode.

34. The method of claim 33, wherein serial sensing signals through the first parallel-to-serial converter identify an existence of the touch and the position of the touch and serial sensing signals through the second parallel-to-serial converter identify only the existence of the touch in the normal mode.

35. The method of claim 28, wherein the apparatus to drive the display panel identifies a position of the touch, only if touching the display panel in substance.

36. 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,

and wherein the physical parameter sensing circuit senses a pressure by closing a switch under a pressure initiated by a touch exerted on a surface of a display panel of the display apparatus, and

wherein the processing circuitry further comprises;

a first amplifier configured to be inputted the signal indicative of sensed light;

a second amplifier configured to be inputted the signal indicative of the sensed physical parameter;

a first parallel-to-serial converter coupled with the first amplifier and selectively coupled with the second amplifier;

a second parallel-to-serial converter selectively coupled with the second amplifier; and

an analog-to-digital converter coupled with the first parallel-to-serial converter and the second parallel-to-serial converter,

when in the normal mode,

the first amplifier amplifies the signal indicative of sensed light,

the second amplifier amplifies the signal indicative of the sensed physical parameter,

the first parallel-to-serial converter is coupled with the first amplifier and the second amplifier, and converts the amplified signal indicative of sensed light and the amplified signal indicative of the sensed physical parameter into first serial sensing signals, and

the analog-to-digital converter converts the first serial sensing signals into first digital sensing signals, and

when in the power saving mode,

the first amplifier is not provided with power,

the second amplifier amplifies the signal indicative of the sensed physical parameter,

the second parallel-to serial converter is coupled with the second amplifier, and converts the amplified signal indicative of the sensed physical parameter into a second sensing signal, and

the analog-to-digital converter converts the second serial sensing signal into a second digital sensing signal.

37. The apparatus of claim 36, 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.

38. The apparatus of claim 36, wherein the physical parameter sensing circuit is a pressure sensing circuit.

39. The apparatus of claim 36, wherein the apparatus to drive the display panel identifies a position of the touch, only if touching the display panel in substance.