# US 12,731,535 B2 · Micro LED display device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,731,535 B2 - Document ID: US12731535B2 - Status: Granted - Kind: B2 - Application number: 19/054,282 - Filed: 2025-02-14 - Published: 2025-09-04 - Granted: 2026-09-08 - Earliest claimed: 2024-02-29 - Assignees: LG Display Co., Ltd. - Applicants: LG Display Co., Ltd. - Inventors: Kyeongtae Min - Web page: https://patentgrep.com/patent/US12731535B2 ## CPC - G09G 3/32: semiconductive, e.g. using light-emitting diodes [LED] - G09G 3/3233: with pixel circuitry controlling the current through the light-emitting element - G09G 3/3291: in which the data driver supplies a variable data voltage for setting the current through, or the voltage across, the light-emitting elements - G09G 2300/0828: forming a digital to analog [D/A] conversion circuit - G09G 2320/045: Compensation of drifts in the characteristics of light emitting or modulating elements - G09G 2330/021: Power management, e.g. power saving - G09G 2330/028: Generation of voltages supplied to electrode drivers in a matrix display other than LCD - H10H 29/30: Active-matrix LED displays - G09G: ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION (arrangements for transferring data between digital computers and displays G06F3/14; static indicating arrangements comprising an association of a number of separate sources or light control cells G09F9/00; static indicating arrangements comprising integral associations of a number of light sources H01J, H01K, H10H, H05B33/12; scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission, details thereof H04N1/00) - H10H: INORGANIC LIGHT-EMITTING SEMICONDUCTOR DEVICES HAVING POTENTIAL BARRIERS ## Abstract Disclosed is a micro-LED display device configured to prevent unwanted light-emission under all driving conditions regardless of a short circuit between a cathode electrode and an anode electrode of a micro-LED. The micro-LED display device includes a display panel including: a plurality of pixel circuits for driving a plurality of micro-LEDs; and a micro-driver for controlling an operation of each of the plurality of pixel circuits; and a power management circuit configured to manage a level of a bias voltage so that a gap voltage as a difference between a negative voltage and the bias voltage used to selectively drive one of the plurality of micro-LEDs is maintained at a value lower than a threshold voltage of each of the plurality of micro-LEDs. ## Claims ### Claim 1 A micro-LED display device comprising: a display panel including: a plurality of pixel circuits configured to drive a plurality of micro-LEDs; and a micro-driver configured to control an operation of each of the plurality of pixel circuits; and a power management circuit configured to manage a level of a bias voltage so that a gap voltage as a difference between a negative voltage and the bias voltage used to selectively drive one of the plurality of micro-LEDs is maintained at a value lower than a threshold voltage of each of the plurality of micro-LEDs, wherein the power management circuit is configured to generate the bias voltage based on a negative feedback voltage fed back from the display panel and a gap setting signal corresponding to the gap voltage. ### Claim 2 (depends on 1) The micro-LED display device of claim 1, wherein the power management circuit is configured to generate the negative voltage and provide the generated negative voltage to the display panel. ### Claim 3 (depends on 2) The micro-LED display device of claim 2, wherein the power management circuit includes: a first voltage generation circuit configured to generate the negative voltage based on an input voltage input from an external input power supply and a voltage setting signal; and a second voltage generation circuit configured to generate the bias voltage based on a reference voltage input from the external input power supply, the gap setting signal, and the negative feedback voltage. ### Claim 4 (depends on 3) The micro-LED display device of claim 3, wherein the second voltage generation circuit includes: a digital-to-analog converter configured to receive the gap setting signal from an external setting unit and to convert the gap setting signal into the gap voltage; and a computation circuit configured to perform computation on the reference voltage, the gap voltage, and the negative feedback voltage to generate the bias voltage. ### Claim 5 (depends on 1) The micro-LED display device of claim 1, wherein the negative voltage is applied to a cathode electrode of a micro-LED from the plurality of micro-LEDs to emit light, the bias voltage is applied to the cathode electrode of a micro-LED from the plurality of micro-LEDs to not emit light, and the bias voltage is higher than the negative voltage. ### Claim 6 (depends on 1) The micro-LED display device of claim 1, wherein the display panel includes: first to 16th row cathode electrodes spaced from each other by a predetermined spacing in a column direction, wherein each of first to 16th row cathode electrodes extends in a row direction of the display panel, wherein the micro-driver is between a column-directional arrangement of the first to 8th row cathode electrodes and a column-directional arrangement of ninth to 16th row cathode electrodes. ### Claim 7 (depends on 6) The micro-LED display device of claim 6, wherein the plurality of pixel circuits are on each of the first to 16th row cathode electrodes and are spaced from each other by a predetermined spacing in a row direction. ### Claim 8 (depends on 7) The micro-LED display device of claim 7, wherein the micro-driver is connected to each of the plurality of pixel circuits via a first anode electrode line and a second anode electrode line. ### Claim 9 (depends on 8) The micro-LED display device of claim 8, wherein the plurality of pixel circuits include: first to eighth micro-LEDs connected to the micro-driver via first anode electrode lines, respectively; and first to eighth redundancy micro-LEDs connected to the micro-driver via second anode electrode lines, respectively. ### Claim 10 (depends on 1) The micro-LED display device of claim 1, wherein each of the plurality of pixel circuits includes: a driving transistor configured to supply a power voltage in response to a gate driving voltage; a first transistor configured to constitute a current path together with the driving transistor in response to a light-emission signal; first to eighth micro-LEDs, each having an anode electrode connected to the first transistor; and a switch circuit configured to selectively connect each of cathode electrodes of the first to eighth micro-LEDs to a power line for the negative voltage or the bias voltage. ### Claim 11 (depends on 10) The micro-LED display device of claim 10, wherein the switch circuit includes: one or more first switches, each of the one or more first switches configured to connect each of the cathode electrodes of the first to eighth micro-LEDs to a power line for the bias voltage; and one or more second switches, each of the one or more second switches being configured to connect each of the cathode electrodes of the first to eighth micro-LEDs to a power line for the negative voltage. ### Claim 12 (depends on 10) The micro-LED display device of claim 10, wherein the switch circuit is configured to apply the negative voltage to the cathode electrode of the micro-LED to emit light and to apply the bias voltage to the cathode electrode of each of remaining micro-LEDs not to emit light. ### Claim 13 A micro-LED display device comprising: a display panel including: a plurality of pixel circuits for driving a plurality of micro-LEDs; and a micro-driver configured to control an operation of each of the plurality of pixel circuits, first to 16th row cathode electrodes extending in a row direction of the display panel and spaced from each by a predefined spacing in a column direction, wherein the micro-driver between a column-directional arrangement of the first to 8th row cathode electrodes and a column-directional arrangement of the ninth to 16th row cathode electrodes, further comprising a power management circuit configured to manage a level of a bias voltage so that a gap voltage as a difference between a negative voltage and the bias voltage used to selectively drive one of the plurality of micro-LEDs is maintained at a value lower than a threshold voltage of each of the plurality of micro-LEDs, wherein the power management circuit is configured to generate the bias voltage based on a negative feedback voltage fed back from the display panel and a gap setting signal corresponding to the gap voltage. ### Claim 14 (depends on 13) The micro-LED display device of claim 13, wherein the negative voltage is applied to a cathode electrode of a micro-LED from the plurality of micro-LEDs to emit light, the bias voltage is applied to the cathode electrode of a micro-LED from the plurality of micro-LEDs to not emit light, and the bias voltage is higher than the negative voltage. ### Claim 15 (depends on 14) The micro-LED display device of claim 14, wherein the power management circuit is configured to generate the negative voltage and provide the generated negative voltage to the display panel. ### Claim 16 (depends on 15) The micro-LED display device of claim 15, wherein the power management circuit includes: a first voltage generation circuit configured to generate the negative voltage based on an input voltage input from an external input power supply and a voltage setting signal; and a second voltage generation circuit configured to generate the bias voltage based on a reference voltage input from the external input power supply, the gap setting signal, and the negative feedback voltage. ### Claim 17 (depends on 16) The micro-LED display device of claim 16, wherein the second voltage generation circuit includes: a digital-to-analog converter configured to receive the gap setting signal from an external setting unit and to convert the gap setting signal into the gap voltage; and a computation circuit configured to perform computation on the reference voltage, the gap voltage, and the negative feedback voltage to generate the bias voltage. ### Claim 18 A micro-LED display device comprising: a display panel including: a plurality of pixel circuits configured to drive a plurality of micro-LEDs; and a micro-driver configured to control an operation of each of the plurality of pixel circuits, wherein each of the plurality of pixel circuits includes: a driving transistor configured to supply a power voltage in response to a gate driving voltage; a first transistor configured to constitute a current path together with the driving transistor in response to a light-emission signal; first to eighth micro-LEDs, each having an anode electrode connected to the first transistor; and a switch circuit configured to selectively connect each of cathode electrodes of the first to eighth micro-LEDs to a power line for a negative voltage or a bias voltage, further comprising: a power management circuit configured to manage a level of the bias voltage so that a gap voltage as a difference between the negative voltage and the bias voltage is maintained at a value lower than a threshold voltage of each of the plurality of micro-LEDs, wherein the power management circuit is configured to generate the bias voltage based on a negative feedback voltage fed back from the display panel and a gap setting signal corresponding to the gap voltage. ### Claim 19 (depends on 18) The micro-LED display device of claim 18, wherein the switch circuit is configured to apply the negative voltage to a cathode electrode of the micro-LED to emit light, and to apply the bias voltage to a cathode electrode of each of remaining micro-LEDs not to emit light. ### Claim 20 (depends on 19) The micro-LED display device of claim 19, wherein the switch circuit includes: one or more first switches, each of the one or more first switches configured to connect each of the cathode electrodes of the first to eighth micro-LEDs to the power line for the bias voltage; and one or more second switches, each of the one or more second switches configured to connect each of the cathode electrodes of the first to eighth micro-LEDs to the power line for the negative voltage.