Brightness based pixel driver power reduction systems and methods

Patent metadata

Field	Value
Publication number	US-12518697-B2
Application number	US-202418883524-A
Country	US
Kind code	B2
Filing date	Sep 12, 2024
Priority date	Sep 19, 2023
Publication date	Jan 6, 2026
Grant date	Jan 6, 2026

Abstract

An electronic device may include a display panel having display pixels and pixel drive circuitry that drives the display pixels based on a set of analog voltages according to display image data. Additionally, the electronic device may include a gamma generator to generate the set of analog voltages and voltage regulating circuitry that adjusts a supply voltage to a portion of the gamma generator based on a brightness setting of the display panel.

First claim

What is claimed is:

1 . An electronic device comprising:
a display panel comprising a plurality of display pixels and pixel drive circuitry configured to drive one or more display pixels of the plurality of display pixels based on a set of analog voltages in accordance with display image data; a gamma generator, which comprises one or more digital-to-analog converters, configured to generate the set of analog voltages; and a voltage regulator configured to adjust a supply voltage to a portion of the gamma generator based on a display brightness value of the display panel.

2 . The electronic device of claim 1 , comprising current regulating circuitry configured to adjust a bias current of an amplifier of the gamma generator based on the display brightness value.

3 . The electronic device of claim 2 , wherein the current regulating circuitry comprises a plurality of current emitters disposed in parallel, wherein the current regulating circuitry is configured to enable a number of the current emitters based on the display brightness value, and wherein the number is larger for a first display brightness value than for a second display brightness value less than the first display brightness value.

4 . The electronic device of claim 1 , wherein the gamma generator comprises a first generator stage configured to generate a set of tap voltages and a second generator stage configured to generate the set of analog voltages based on the set of tap voltages, wherein the second generator stage comprises a plurality of amplifiers configured to buffer the set of tap voltages, the set of analog voltages, or both, and wherein the portion of the gamma generator comprises the plurality of amplifiers such that the voltage regulator is configured to adjust the supply voltage to the plurality of amplifiers based on the display brightness value.

5 . The electronic device of claim 4 , comprising current regulating circuitry configured to adjust bias currents of the plurality of amplifiers based on the display brightness value.

6 . The electronic device of claim 1 , wherein the pixel drive circuitry comprises a source amplifier configured to buffer an analog voltage, of the set of analog voltages, provided to a pixel of the plurality of display pixels, and wherein the voltage regulator is configured to adjust the supply voltage to the source amplifier based on the display brightness value.

7 . The electronic device of claim 6 , wherein the voltage regulator is configured to provide the adjusted supply voltage to the source amplifier and the portion of the gamma generator.

8 . The electronic device of claim 1 , comprising a controller configured to:
generate a voltage control signal based on the display brightness value; and provide the voltage control signal to the voltage regulator to regulate adjustment of the supply voltage, wherein the controller is configured to instigate changes to the supply voltage during a non-emission period of the plurality of display pixels between a first beginning of a first image frame and a second beginning of a second image frame immediately subsequent to the first image frame.

9 . The electronic device of claim 1 , wherein the voltage regulator comprises a power management integrated circuit (PMIC).

10 . The electronic device of claim 1 , wherein the plurality of display pixels comprises a plurality of organic light emitting diodes (OLEDs).

11 . The electronic device of claim 1 , wherein the display brightness value is based on a user input, an ambient light reading, a time of day, or any combination thereof.

12 . A method comprising:
obtaining, via a controller, a display brightness value of a display panel for an image frame; determining, via the controller, a supply voltage based on the display brightness value; and supplying, via a voltage regulator, the supply voltage to at least one of a plurality of amplifiers of a gamma generator of the display panel and a plurality of source amplifiers of pixel drive circuitry of the display panel, wherein the gamma generator comprises one or more digital-to-analog converters.

13 . The method of claim 12 , comprising:
determining a bias current based on the display brightness value; and supplying, via current regulating circuitry, the bias current to the plurality of amplifiers of the gamma generator.

14 . The method of claim 12 , wherein the gamma generator comprises a first generator stage configured to generate a set of tap voltages and a second generator stage configured to generate a set of analog voltages based on the set of tap voltages, wherein the pixel drive circuitry is configured to drive display pixels of the display panel based on the set of analog voltages in accordance with display image data, and wherein the second generator stage comprises the plurality of amplifiers.

15 . An electronic device comprising:
a display panel comprising a plurality of display pixels and pixel drive circuitry configured to drive one or more display pixels of the plurality of display pixels based on a set of analog voltages in accordance with display image data; a gamma generator, which comprises one or more digital-to-analog converters, configured to generate the set of analog voltages; and current regulating circuitry configured to adjust a bias current of an amplifier of the gamma generator based on a display brightness value of the display panel.

16 . The electronic device of claim 15 , comprising a voltage regulator configured to adjust a supply voltage to a portion of the gamma generator, a portion of the pixel drive circuitry, or both, based on the display brightness value.

17 . The electronic device of claim 16 , wherein the voltage regulator is configured to adjust the supply voltage to the portion of the pixel drive circuitry, wherein the portion of the pixel drive circuitry comprises a plurality of source amplifiers configured to provide selected analog voltages of the set of analog voltages to display pixels of the plurality of display pixels.

18 . The electronic device of claim 15 , wherein the gamma generator comprises a first generator stage configured to generate a set of tap voltages and a second generator stage configured to generate the set of analog voltages based on the set of tap voltages, wherein the second generator stage comprises a plurality of amplifiers configured to buffer the set of tap voltages, the set of analog voltages, or both, and wherein the plurality of amplifiers comprises the amplifier such that the current regulating circuitry is configured to adjust the bias current to the amplifier based on the display brightness value.

19 . The electronic device of claim 18 , wherein the first generator stage comprises a second plurality of amplifiers configured to buffer the set of tap voltages, and wherein the current regulating circuitry is configured to adjust the bias current to the second plurality of amplifiers.

20 . The electronic device of claim 15 , comprising a controller configured to:
generate a current control signal based on the display brightness value; and provide the current control signal to the current regulating circuitry to regulate adjustment of the bias current, wherein the controller is configured to instigate changes to the bias current during a non-emission period of the plurality of display pixels between a first beginning of a first image frame and a second beginning of a second image frame immediately subsequent to the first image frame.

Assignees

• Apple Inc

Inventors

• Agarwal Shatam
• Zalatimo David S
• Zheng Fenghua
• Gomez Jason N
• Hammler Nikolaus
• Cruce Patrick R
• Calayir Vehbi
• Zhang Yue

Classifications

• G09G3/2007

  Display of intermediate tones · CPC title

• G09G2330/028

  Generation of voltages supplied to electrode drivers in a matrix display other than LCD · CPC title

• G09G2330/021

  Power management, e.g. power saving · CPC title

• G09G3/3233 Primary

  with pixel circuitry controlling the current through the light-emitting element · CPC title