Display driving circuit

Patent metadata

Field	Value
Publication number	US-9898997-B2
Application number	US-201514606282-A
Country	US
Kind code	B2
Filing date	Jan 27, 2015
Priority date	Jan 27, 2014
Publication date	Feb 20, 2018
Grant date	Feb 20, 2018

Abstract

The display driving circuit including a type detector for receiving a data packet including a 2-bit embedded signal, in which a clock signal embedded in a data signal, and outputting a first reference clock or a second reference clock different from the first reference clock according to a type of the data packet, a window generator for receiving multi-phase clocks and providing to the type detector a first window reference and a second window reference different from the first window reference to be used in determining the type of the data packet, a buffer for delaying the first reference clock by a first interval and delaying the second reference clock by a second interval different from the first interval, and a multiplexer for multiplexing the delayed first and second reference clocks and outputting a multiplexed reference clock may be provided.

First claim

What is claimed is:

1. A display driving circuit comprising:
a clock recovery circuit configured to receive a data packet including a 2-bit embedded signal, in which a clock signal is embedded in a data signal, and generate a multiplexed reference clock having a rising edge at a middle place of a first bit of the data packet;
a delay locked loop configured to receive the multiplexed reference clock and generate multi-phase clocks sequentially delayed by a unit interval, the unit interval corresponding to an interval of one bit; and
a sampler configured to extract a plurality of data signals from the data packet using the multi-phase clocks, the sampler including a logic configured to extract a 1-bit data signal from the 2-bit embedded signal,
wherein the rising edge of the multiplexed reference clock is not generated at a place between two adjacent bits of the data packet.

2. The display driving circuit of claim 1 , wherein the clock recovery circuit comprises:
a type detector configured to output one of a first reference clock and a second reference clock different from the first reference clock according to a type of the data packet;
a first buffer circuit configured to delay the first reference clock by a first interval;
a second buffer circuit configured to delay the second reference clock by a second interval different from the first interval; and
a multiplexer connected to the first and second buffer circuits and configured to multiplex the delayed first and second reference clocks to generate the multiplexed reference clock.

3. The display driving circuit of claim 2 , further comprising:
a window generator configured to receive at least some of the multi-phase clocks and the data packet and provide a window reference used to determine a type of the data packet provided to the type detector.

4. The display driving circuit of claim 2 , wherein the first interval is half the unit interval and the second interval is greater than the first interval by the unit interval.

5. The display driving circuit of claim 2 , further comprising:
a bias generator configured to receive some of the multi-phase clocks and provide a bias to the first buffer circuit and the second buffer circuit.

6. The display driving circuit of claim 5 , wherein
the first buffer circuit is configured to delay the first reference clock by half the unit interval,
the second buffer circuit is configured to delay the second reference clock by 1.5 times the unit interval, and
the bias generator is configured to lock the bias such that the first and second buffer circuits are activated to delay the multiplexed reference clock by an integer multiple of half the unit interval.

7. The display driving circuit of claim 2 , wherein
the delay locked loop includes a lock detector, the lock detector configured to detect whether the multi-phase clocks are locked or not, and
when an operation signal of the lock detector is input, the type detector is configured to output one of the first reference clock and the second reference clock according to the type of the data packet.

8. The display driving circuit of claim 1 , wherein the data packet includes
a first type data packet having the 2-bit embedded signal, which does not include a transition, and a transition value of the 2-bit embedded signal appearing right after the 2-bit embedded signal, and
a second type data packet having the 2-bit embedded signal, which includes a transition.

9. A display driving circuit comprising:
a clock recovery circuit configured to receive a data packet including an embedded signal and generate a multiplexed reference clock having a rising edge at a middle place of one bit of the data packet, the data packet including a reference bit, the reference bit having a value depending on a type of the data packet;
a delay locked loop configured to receive the multiplexed reference clock and generate multi-phase clocks sequentially delayed by a unit interval, the unit interval corresponding to an interval of one bit; and
a sampler configured to extract a plurality of data signals including an 1-bit data signal using the multi-phase clocks, the 1-bit data signal having a value of the reference bit,
wherein the rising edge of the multiplexed reference clock is not generated at a place between two adjacent bits of the data packet.

10. The display driving circuit of claim 9 , wherein when the data packet consists of (N+1) bits while including an N-bit data signal, a delay locked loop is configured to generate the multi-phase clocks of (N+1) signals and the sampler is configured to extract the 1-bit data signal using Nth and (N+1)th signals of the multi-phase clocks and output a plurality of data signals of N bit.

11. The display driving circuit of claim 9 , wherein the clock recovery circuit includes
a type detector configured to output one of a first reference clock and a second reference clock according to the type of the data packet, the first reference clock being different from the second reference clock;
a first buffer circuit configured to delay the first reference clock by a first interval;
a second buffer circuit configured to delay the second reference clock by a second interval different from the first interval; and
a multiplexer connected to the first and second buffer circuits and configured to multiplex the delayed first and second reference clocks to generate the multiplexed reference clock.

12. The display driving circuit of claim 11 , further comprising:
a bias generator configured to receive some of the multi-phase clocks and provide a bias to the first and second buffer circuits.

13. The display driving circuit of claim 11 , wherein the delay locked loop is further configured to generate a lock detector signal and the type detector is further configured to output one of the first reference clock and the second reference clock according to the type of the data packet in response to the lock detector signal.

14. The display driving circuit of claim 1 , further comprising:
a bias generator configured to receive some of the multi-phase clocks and provide a bias to the clock recovery circuit to adjust delay of the multiplexed reference clock by 0.5 times of an interval of one bit.

15. The display driving circuit of claim 9 , further comprising:
a bias generator configured to receive some of the multi-phase clocks and provide a bias to the clock recovery circuit to adjust delay of the multiplexed reference clock by 0.5 times of an interval of one bit.

Assignees

• Samsung Electronics Co Ltd
• Postech Academia Ind Collaboration Foundation

Inventors

• Baek Dong Hoon
• Sim Jae Yoon
• Lee Dong Myung
• Lee Jae Youl

Classifications

• G09G2310/08

  Details of timing specific for flat panels, other than clock recovery · CPC title

• G09G2310/0297

  Special arrangements with multiplexing or demultiplexing of display data in the drivers for data electrodes, in a pre-processing circuitry delivering display data to said drivers or in the matrix panel, e.g. multiplexing plural data signals to one D/A converter or demultiplexing the D/A converter output to multiple columns · CPC title

• G09G5/008 Primary

  Clock recovery · CPC title

• G09G2330/06

  Handling electromagnetic interferences [EMI], covering emitted as well as received electromagnetic radiation · CPC title