Driving circuit for radio frequency plasma display panel

• US 6,661,394 B1
• Filed: 04/17/2000
• Issued: 12/09/2003
• Est. Priority Date: 04/17/1999
• Status: Expired due to Fees

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Choi, Jeong Pil
• Primary Examiner(s): Shalwala, Bipin
• Assistant Examiner(s): Kovalick, Vincent E.
• Application Number:
  US09/551,593
• Time in Patent Office: 1,331 Days
• Field of Search: 345/60, 345/62, 345/63, 345/65, 345/66, 345/67, 345/204, 345/690, 345/214, 315/169.4, 315/167, 313/484, 313/514
• US Class Current: 345/60
• CPC Class Codes: G09G 2310/0218 with collection of electrodes in groups for n-dimensional addressing
• CPC Class Codes: G09G 3/2807 with discharge activated by high-frequency signals specially adapted therefor
• CPC Class Codes: G09G 3/296 Driving circuits for producing the waveforms applied to the driving electrodes
• CPC Class Codes: G09G 3/2986 with more than 3 electrodes involved in the operation

Abstract

A driving circuit for a radio frequency plasma display panel that is capable of effectively making an impedance matching between a radio frequency signal generator and a panel. In the circuit, radio frequency electrode lines are divided into a plurality of groups. A plurality of impedance matchers are independently connected to each group of the radio frequency electrode lines to match impedance of input and output terminals thereof. Accordingly, an impedance difference between the radio frequency electrode lines caused by a length difference of radio frequency supply lines is uniformly compensated, so that a maximum power of radio frequency signal can be applied to each radio frequency electrode line to provide a stable operation of the panel as well as to improve a picture quality.

Claims

1. A driving circuit for a plasma display panel using a radio frequency discharge, comprising:

a radio frequency generator which applies radio frequency signals to a plurality of radio frequency electrode lines;

one or more radio frequency amplifiers which amplify the radio frequency signals; and

a plurality of impedance matching means for matching impedance between the amplified radio frequency signals and the plasma display panel, wherein the radio frequency electrode lines are divided into a plurality of groups and the plurality of impedance matching units have different impedance values in accordance with a length difference between radio frequency supply lines connected from the radio frequency generator to said groups.

2. The driving circuit as claimed in claim 1, wherein the plurality of radio frequency amplifiers are arranged independently of the plurality of impedance matching means.

3. The driving circuit as claimed in claim 1, further comprising:

a plurality of radio frequency amplifying means, being commonly connected to input terminals of the plurality of impedance matching means, to amplify and output an input radio frequency signal.

4. The driving circuit as claimed in claim 3, wherein said plurality of impedance matching means has a different element value in such a manner to compensate for impedance differentiated in accordance with a length difference in supply lines of the radio frequency signal.

5. The driving circuit as claimed in claim 1, wherein the detector detects the brightness level for each field or frame using the input image signal to calculate an average brightness level and output the same to the controller.

6. The driving circuit as claimed in claim 5, wherein the controller divides the average brightness level into a plurality of regions in accordance with a magnitude of the average brightness level and sets the impedance matching level in correspondence with the regions.

7. The driving circuit as claimed in claim 5, wherein the controller controls a switch included in the impedance matcher to adjust the impedance matching value of the impedance matching means.

8. A radio frequency driving circuit for a plasma display panel using a radio frequency discharge, comprising:

a radio frequency generator which applies radio frequency signals to a plurality of radio frequency electrode lines;

one or more radio frequency amplifiers which amplify the radio frequency signals;

impedance matching means for matching impedance between the amplified radio frequency signals and the plasma display;

a detector which detects a brightness level of an image signal input to the plasma display panel; and

a controller which adjusts an impedance matching level of the impedance matcher in accordance with the detected brightness level.

9. A system for driving a plasma panel display, comprising:

a plurality of impedance matchers connected to respective ones of a plurality of RF electrodes in the plasma panel display, each of said impedance matchers matching an impedance of an input terminal with an impedance of a respective one of the RF electrodes; and

a plurality of signal lines, each of said signal lines connecting one of said impedance matchers to a respective one of the RF electrodes, said signal lines have substantially a same length.

10. A system for driving a plasma panel display, comprising:

a plurality of impedance matchers connected to respective ones of a plurality of RF electrodes in the plasma panel display, each of said impedance matchers matching an impedance of an input terminal with an impedance of a respective one of the RF electrodes, wherein at least one of the impedance matchers matches impedance by an amount sufficient to allow a maximum signal to be input into a respective RF electrode.

11. A system for driving a plasma panel display, comprising:

a first impedance matcher connected to a first plurality of RF electrodes in the plasma display panel;

a second impedance matcher connected to a second plurality of RF electrodes in the plasma display panel, wherein said second plurality of RF electrodes are different electrodes from the first plurality of RF electrodes, and wherein the first impedance matcher matches an impedance of an input terminal with impedances of the first plurality of RF electrodes.

12. The system as claimed in claim 11, wherein the second impedance matcher matches an impedance of the input terminal with impedances of the second plurality of RF electrodes.

13. The system as claimed in claim 11, further comprising:

a first plurality of signal lines connecting the first impedance matcher with respective ones of the first plurality of RF electrodes, said first plurality of signal lines having substantially a same length.

14. The system as claimed in claim 13, further comprising:

a second plurality of signal lines connecting the second impedance matcher with respective ones of the second plurality of RF electrodes, said second plurality of signal lines having substantially a same length.

15. The system as claimed in claim 14, wherein the length of the first plurality of signal lines equals the length of the second plurality of signal lines.

16. The system as claimed in claim 11, further comprising:

an amplifier connected to the first impedance matcher and the second impedance matcher; and

first and second lines connecting the amplifier to respective ones of the first impedance matcher and the second impedance matcher, wherein said first and second lines have different lengths, wherein said first impedance matcher and the second impedance matcher compensate for differences in impedances generated by the different lengths of the first and second lines.

17. A system for driving a plasma display panel, comprising:

an impedance matcher connected between an input terminal and the plasma display panel, said impedance matcher matching an impedance of the input terminal with an impedance of an RF electrode in the plasma display panel based on a brightness correction value.

18. The system as claimed in claim 17, wherein the brightness correction value is based on an average brightness of a plurality of image signals.

19. The system as claimed in claim 17, further comprising:

a brightness detection unit which compures the brightness correction value by classifying the average brightness into a plurality of categories corresponding to different levels of brightness.