EP-4742228-A1 - ELECTRONIC DEVICE FOR DRIVING PIXEL, AND CONTROL METHOD THEREFOR

EP4742228A1EP 4742228 A1EP4742228 A1EP 4742228A1EP-4742228-A1

Abstract

An electronic device is disclosed. The electronic device comprises a driving unit, an inorganic light-emitting element, and a pixel circuit for controlling the inorganic light-emitting element on the basis of a plurality of signals that are output from the driving unit, wherein the pixel circuit can include: a first circuit which includes a switching transistor, and which provides, to the inorganic light-emitting element, through the switching transistor, a first current based on a first control voltage from among the plurality of signals; and a second circuit, which includes a charging element connected to the gate of the switching transistor, charges the charging element with a second current based on a second control voltage from among the plurality of signals, and blocks the supply of the first current to the inorganic light-emitting element by blocking the switching transistor when the voltage of the charging element reaches a preset voltage.

Inventors

PARK, WONKEUN
JUNG, YOUNGKI
KIM, DONGHWAN
OH, DONGGUN

Assignees

Samsung Electronics Co., Ltd.

Dates

Publication Date: 20260513
Application Date: 20240924

Claims (15)

An electronic apparatus comprising: a driving unit; an inorganic light-emitting element; and pixel circuitry controlling the inorganic light-emitting element based on a plurality of signals output from the driving unit, the pixel circuitry comprising: first circuitry including a switching transistor, and providing a first current based on a first control voltage among the plurality of signals to the inorganic light-emitting element through the switching transistor; and second circuitry including a charging element connected to a gate of the switching transistor, charging the charging element with a second current based on a second control voltage among the plurality of signals, and cutting off a supply of the first current to the inorganic light-emitting element as the switching transistor is blocked based on a voltage of the charging element reaching a predetermined voltage.
The electronic apparatus of claim 1, wherein the first circuitry further includes a first driving transistor, supplies, based on a reset signal among the plurality of signals, a first initial voltage among the plurality of signals to a gate of the first driving transistor, and supplies, based on a data setting signal among the plurality of signals, the first control voltage to a gate of the first driving transistor, and the second circuitry further includes a second driving transistor, supplies, based on the reset signal, the first initial voltage to a gate of the second driving transistor, and supplies, based on the data setting signal, the second control voltage to a gate of the second driving transistor.
The electronic apparatus of claim 2, wherein the first circuitry supplies, based on a light-emitting signal, a first driving voltage among the plurality of signals, to a source of the first driving transistor, and provides the first current based on a gate-source voltage of the first driving transistor to the inorganic light-emitting element through the switching transistor, and the second circuitry supplies, based on the light-emitting signal, a second driving voltage among the plurality of signals to a source of the second driving transistor, and charges the charging element with the second current based on a gate-source voltage of the second driving transistor.
The electronic apparatus of claim 3, wherein the inorganic light-emitting element emits light of luminance corresponding to magnitude of the first current, and a turn-on time of the switching transistor is determined based on magnitude of the second current.
The electronic apparatus of claim 3, wherein the first current is decreased as the first control voltage is increased, and increased as the first control voltage is decreased, and the second current is decreased as the second control voltage is increased, and increased as the second control voltage is decreased.
The electronic apparatus of claim 2, wherein the second circuitry supplies a second initial voltage to the charging element based on the reset signal, and the second initial voltage is a voltage that allows the switching transistor to be turned on.
The electronic apparatus of claim 2, wherein one end of the inorganic light-emitting element is grounded while the other end is connected to the switching transistor, and the first initial voltage is supplied to the other end based on the reset signal.
The electronic apparatus of claim 2, wherein the first circuit further includes a first capacitor connected to a gate of the first driving transistor, and a gate voltage of the first driving transistor is maintained through the first capacitor, and the second circuitry further includes a second capacitor connected to a gate of the second driving transistor, and a gate voltage of the second driving transistor is maintained through the second capacitor.
The electronic apparatus of claim 8, wherein the charging element includes a third capacitor, and capacitance of the third capacitor is greater than capacitance of each of the first capacitor and the second capacitor.
The electronic apparatus of claim 2, wherein a W/L ratio of the first driving transistor is greater than a W/L ratio of the second driving transistor.
The electronic apparatus of claim 1, wherein each of the plurality of signals is a square signal or a DC signal.
A control method for an electronic apparatus, the method comprising: providing a first current based on a first control voltage among a plurality of signals output from a driving unit of the electronic apparatus to an inorganic light-emitting element of the electronic apparatus through a switching transistor, and charging a charging element connected to a gate of the switching transistor with a second current based on a second control voltage among the plurality of signals; and cutting off a supply of the first current to the inorganic light-emitting element as the switching transistor is blocked based on a voltage of the charging element reaching a predetermined voltage.
The method of claim 12 further comprising: supplying, based on a reset signal among the plurality of signals, a first initial voltage among the plurality of signals to a gate of a first driving transistor included in first circuitry and a gate of a second driving transistor included in second circuitry; and supplying, based on a data setting signal among the plurality of signals, the first control voltage to a gate of the first driving transistor and the second control voltage to a gate of the second driving transistor.
The method of claim 13, the charging including: supplying, based on a light-emitting signal, a first driving voltage among the plurality of signals to a source of the first driving transistor, and a second driving voltage among the plurality of signals to a source of the second driving transistor; and providing the first current based on a gate-source voltage of the first driving transistor to the inorganic light-emitting element through the switching transistor, and charging the charging element with the second current based on a gate-source voltage of the second driving transistor.
The method of claim 14, wherein the inorganic light-emitting element emits light of luminance corresponding to magnitude of the first current, and a turn-on time of the switching transistor is determined based on magnitude of the second current.

Description

[Technical Field] This disclosure relates to an electronic apparatus and a control method thereof, and particularly, to an electronic apparatus for driving a pixel and a control method thereof. [Background Art] With an advancement in electronic technologies, various types of electronic apparatuses have been developed. In particular, display devices using a micro LED have been recently developed. Most micro LED display models adopt a pulse width modulation (PWM) internal compensation driving method in which a driving current peak is fixed and a pulse width is adjusted. This is because in the case where a pulse amplitude modulation (PAM) driving method is used, a current peak may vary depending on gray, thereby causing a color shift phenomenon stemming from the attributes of micro LEDs. In a conventional PWM internal compensation driving method, part of gate in panel (GIP) waveforms use a triangle wave, and accordingly, various types of image quality problems may be caused. [Disclosure of Invention] [Solution to Problem] According to one embodiment, an electronic apparatus includes a driving unit, an inorganic light-emitting element, and pixel circuitry controlling the inorganic light-emitting element based on a plurality of signals output from the driving unit, the pixel circuitry including first circuitry that includes a switching transistor, and provides a first current based on a first control voltage among the plurality of signals to the inorganic light-emitting element through the switching transistor, and second circuitry that includes a charging element connected to a gate of the switching transistor, charges the charging element with a second current based on a second control voltage among the plurality of signals, and cuts off a supply of the first current to the inorganic light-emitting element as the switching transistor is blocked based on a voltage of the charging element reaching a predetermined voltage. Additionally, the first circuitry may further include a first driving transistor, supply, based on a reset signal among the plurality of signals, a first initial voltage among the plurality of signals to a gate of the first driving transistor, and supply, based on a data setting signal among the plurality of signals, the first control voltage to a gate of the first driving transistor, while the second circuitry may further include a second driving transistor, supply, based on the reset signal, the first initial voltage to a gate of the second driving transistor, and supply, based on the data setting signal, the second control voltage to a gate of the second driving transistor. Additionally, the first circuitry may supply, based on a light-emitting signal, a first driving voltage among the plurality of signals to a source of the first driving transistor, and provide the first current based on a gate-source voltage of the first driving transistor to the inorganic light-emitting element through the switching transistor, while the second circuitry may supply, based on the light-emitting signal, a second driving voltage among the plurality of signals to a source of the second driving transistor, and charge the charging element with the second current based on a gate-source voltage of the second driving transistor. Further, the inorganic light-emitting element may emit light of luminance corresponding to magnitude of the first current, and a turn-on time of the switching transistor may be determined based on magnitude of the second current. Additionally, the first current may be decreased as the first control voltage is increased, and increased as the first control voltage is decreased, and the second current may be decreased as the second control voltage is increased, and increased as the second control voltage is decreased. Further, the second circuitry may supply a second initial voltage to the charging element based on the reset signal, and the second initial voltage may be a voltage that allows the switching transistor to be turned on. Additionally, one end of the inorganic light-emitting element may be grounded, while the other end may be connected to the switching transistor, and the first initial voltage may be supplied to the other end based on the reset signal. Further, the first circuit may further include a first capacitor connected to a gate of the first driving transistor, and a voltage of the gate of the first driving transistor may be maintained through the first capacitor, and the second circuitry may further include a second capacitor connected to a gate of the second driving transistor, and a voltage of the gate of the second driving transistor may be maintained through the second capacitor. Additionally, the charging element may include a third capacitor, and capacitance of the third capacitor may be greater than capacitance of each of the first capacitor and the second capacitor. Further, a W/L ratio of the first driving transistor may be greater than a W/L ratio of the second dr