Display drive circuit and standby power reduction method thereof

Patent metadata

Field	Value
Publication number	US-9754521-B2
Application number	US-201414152144-A
Country	US
Kind code	B2
Filing date	Jan 10, 2014
Priority date	Mar 14, 2013
Publication date	Sep 5, 2017
Grant date	Sep 5, 2017

Abstract

A display driving circuit in accordance with the inventive concepts may include a source amplifier. The source amplifier may include an output transistor configured to amplify an input signal to generate an output signal, and charge a source line of a display panel using the output signal. The source amplifier may include an output transistor switch configured to control the output transistor, and a switch control block configured to receive configuration bits including on/off time information of the output transistor switch to generate a switch control signal. The on/off time information includes information for turning on the output transistor switch in synchronization with a horizontal synchronous signal associated with the display panel, and information for turning off the output transistor switch at a time when the source line of the display panel is charged to a desired charge level.

First claim

What is claimed is:

1. A display driving circuit, comprising:
a source amplifier including,
an output transistor configured to,
amplify an input signal to generate an output signal, and
charge a source line of a display panel using the output signal, and

an output transistor switch configured to control the output transistor; and

a switch control block configured to receive configuration bits including on/off time information of the output transistor switch to generate a switch control signal, the on/off time information including,
information for turning on the output transistor switch in synchronization with a horizontal synchronous signal associated with the display panel, and
information for turning off the output transistor switch at a time when the source line of the display panel is substantially fully charged.

2. The display driving circuit of claim 1 , wherein the output transistor includes a pair of transistors, the pair of transistors including a PMOS transistor and an NMOS transistor, and drains of the PMOS transistor and the NMOS transistor are connected to each other.

3. The display driving circuit of claim 2 , wherein the output transistor switch comprises:
a first switch connected to a gate of the PMOS transistor and configured to connect or cut off a control signal of the PMOS transistor according to the switch control signal;
a second switch connected to a gate of the NMOS and configured to connect or cut off a control signal of the NMOS transistor according to the switch control signal;
a third switch configured to control a voltage difference between a gate of the PMOS transistor and a source of the PMOS transistor according to the switch control signal; and
a fourth switch configured to control a voltage difference between a gate of the NMOS transistor and a source of the NMOS transistor according to the switch control signal.

4. The display driving circuit of claim 3 , wherein each of the third switch and the fourth switch is a MOSFET switch.

5. The display driving circuit of claim 1 , wherein the switch control signal rises toward a high level at a time when the source line of the display panel begins to be charged, and the switch control signal falls toward a low level at a time when the source line of the display panel is substantially fully charged.

6. The display driving circuit of claim 5 , wherein the output transistor switch is turned on if the switch control signal rises toward a high level, and the output transistor switch is turned off if the switch control signal falls toward a low level.

7. The display driving circuit of claim 1 , further comprising:
a digital to analog converter (DAC) configured to receive RGB data to generate the input signal.

8. A display driving circuit, comprising:
a source driver integrated circuit configured to receive information data, the information data including RGB data and configuration bits, the source driver integrated circuit including,
an output circuit configured to,
amplify the RGB data, and
output, during at least a portion of a horizontal time period associated with a display panel, the amplified RGB data to at least one source line of the display panel, and

an output circuit switch configured to control whether the output circuit outputs the amplified RGB data according to a switch control signal that is based on the configuration bits, the configuration bits indicating whether the at least one source line has been substantially fully charged.

9. The display driving circuit of claim 8 , wherein the output circuit switch is configured to control the output circuit to not output the amplified RGB data during a portion of the horizontal time period if the at least one source line is substantially fully charged.

10. The display driving circuit of claim 9 , wherein the at least one source line is substantially fully charged if a voltage at a first node of the at least one source line is equal to a voltage at a second node of the at least one source line, the first node receiving the amplified RGB data before the second node.

11. The display driving circuit of claim 8 , further comprising:
a switch control block configured to generate the switch control signal based on the configuration bits.

12. The display driving circuit of claim 8 , further comprising:
a timing controller configured to,
generate the information data based on received image data, and
send the information data to the source driver integrated circuit.

Assignees

• Samsung Electronics Co Ltd

Inventors

• Ryu Seong-Young
• Park Hyunsang
• Choi Sungpil

Classifications

• G09G2310/08

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

• G09G3/20 Primary

  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 title

• G09G2330/022

  in absence of operation, e.g. no data being entered during a predetermined time · CPC title

• G09G2310/0275

  Details of drivers for data electrodes, other than drivers for liquid crystal, plasma or OLED displays, not related to handling digital grey scale data or to communication of data to the pixels by means of a current · CPC title