CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of priority to Chinese Patent Application No. 201810770131.6 filed on Jul. 13, 2018, the contents of which are incorporated herein in their entirety by reference.

TECHNICAL FIELD

The present disclosure relates to the field of display technologies, and in particular, to a driving unit, a driving method thereof, a gate driving circuit, and a display substrate.

BACKGROUND

When driving organic light-emitting diodes (OLEDs) in an OLED display panel, the display brightness of the display panel may be non-uniform due to performance differences (e.g., process-induced differences, aging-induced differences) of the driving transistors or the OLEDs. Therefore, it is often necessary to compensate for the performance of the driving transistors or the OLEDs.

SUMMARY

In an aspect, the present disclosure provides a driving unit including: a shift register including a pull-up node, a pull-down node and a driving signal output terminal; and a first output circuit configured to output a double pulse signal in a preset time period under control of a voltage of the pull-up node, a voltage of the pull-down node and a voltage provided through the driving signal output terminal.

According to an embodiment of the present disclosure, the first output circuit includes: a first control sub-circuit, a second control sub-circuit and an output sub-circuit; the first control sub-circuit and the output sub-circuit are coupled at a first node, and the first control sub-circuit, the second control sub-circuit and the output sub-circuit are coupled at a second node;

the first control sub-circuit is coupled to the pull-up node and the pull-down node, and is configured to control a voltage at the first node to be at an active level in the preset time period under control of the voltage of the pull-up node, the voltage of the pull-down node, and a voltage at the second node, wherein the preset time period includes: a first sub-period, a second sub-period and a third sub-period which are successively arranged;

the second control sub-circuit is coupled to the pull-down node and the driving signal output terminal, and is configured to control the voltage at the second node to be at an inactive level in the first sub-period and the third sub-period and to be at the active level in the second sub-period under control of the voltage of the pull-down node and the voltage provided through the driving signal output terminal; and

the output sub-circuit is coupled to a first signal output terminal, and is configured to output a voltage at the active level through the first signal output terminal in response to the voltage at the first node being at the active level and the voltage at the second node being at the inactive level, and output a voltage at the inactive level through the first signal output terminal in response to the voltage at the second node being at the active level.

According to an embodiment of the present disclosure, the first control sub-circuit includes: a first transistor, a second transistor, and a third transistor;

a control electrode of the first transistor is coupled to the pull-up node, a first electrode of the first transistor is coupled to a first control signal input terminal, and a second electrode of the first transistor is coupled to the first node;

a control electrode of the second transistor is coupled to the pull-down node, a first electrode of the second transistor is coupled to the first node, and a second electrode of the second transistor is coupled to a first operating power supply terminal, wherein the first operating power supply terminal is configured to provide a first operating voltage at the inactive level; and

a control electrode of the third transistor is coupled to the second node, a first electrode of the third transistor is coupled to the first node, and a second electrode of the third transistor is coupled to the first operating power supply terminal.

According to an embodiment of the present disclosure, the second control sub-circuit includes: a fourth transistor and a fifth transistor;

a control electrode of the fourth transistor is coupled to the pull-down node, a first electrode of the fourth transistor is coupled to a second operating power supply terminal, and a second electrode of the fourth transistor is coupled to the second node, wherein the second operating power supply terminal is configured to provide a second operating voltage at the active level; and

a control electrode of the fifth transistor is coupled to the driving signal output terminal, a first electrode of the fifth transistor is coupled to the second node, and a second electrode of the fifth transistor is coupled to a second control signal input terminal.

According to an embodiment of the present disclosure, the output sub-circuit includes: a sixth transistor, a seventh transistor, an eighth transistor and a first capacitor,

a control electrode of the sixth transistor is coupled to the first control signal input terminal, a first electrode of the sixth transistor is coupled to the second operating power supply terminal, and a second electrode of the sixth transistor is coupled to the first node;

a control electrode of the seventh transistor is coupled to the first node, a first electrode of the seventh transistor is coupled to the second operating power supply terminal, and a second electrode of the seventh transistor is coupled to the first signal output terminal;

a control electrode of the eighth transistor is coupled to the second node, a first electrode of the eighth transistor is coupled to the first signal output terminal, and a second electrode of the eighth transistor is coupled to the first operating power supply terminal; and

a first terminal of the first capacitor is coupled to the first node, and a second terminal of the first capacitor is coupled to the first signal output terminal.

According to an embodiment of the present disclosure, the output sub-circuit includes: a sixth transistor, a seventh transistor, an eighth transistor and a first capacitor;

a control electrode and a first electrode of the sixth transistor are respectively coupled to a third control signal input terminal, and a second electrode of the sixth transistor is coupled to the first node;

a control electrode of the seventh transistor is coupled to the first node, a first electrode of the seventh transistor is coupled to the third control signal input terminal, and a second electrode of the seventh transistor is coupled to the first signal output terminal;

a control electrode of the eighth transistor is coupled to the second node, a first electrode of the eighth transistor is coupled to the first signal output terminal, and a second electrode of the eighth transistor is coupled to the first operating power supply terminal; and

a first terminal of the first capacitor is coupled to the first node, and a second terminal of the first capacitor is coupled to the first signal output terminal.

According to an embodiment of the present disclosure, the driving unit further includes: a second output circuit;

the second output circuit is coupled to the pull-up node, the pull-down node, and the first signal output terminal, respectively, and is configured to output a voltage at the active level through a second signal output terminal in the preset time period under control of the voltage of the pull-up node and the voltage of the pull-down node.

According to an embodiment of the present disclosure, the second output circuit includes: a ninth transistor and a tenth transistor;

a control electrode of the ninth transistor is coupled to the pull-up node, a first electrode of the ninth transistor is coupled to the first control signal input terminal, and a second electrode of the ninth transistor is coupled to the second signal output terminal; and

a control electrode of the tenth transistor is coupled to the pull-down node, a first electrode of the tenth transistor is coupled to the second signal output terminal, and a second electrode of the tenth transistor is coupled to the first operating power supply terminal.

According to an embodiment of the present disclosure, the driving unit further includes a second output circuit;

the second output circuit includes: a ninth transistor and a tenth transistor;

a control electrode of the ninth transistor is coupled to the pull-up node, a first electrode of the ninth transistor is coupled to the first control signal input terminal, and a second electrode of the ninth transistor is coupled to a second signal output terminal; and

a control electrode of the tenth transistor is coupled to the pull-down node, a first electrode of the tenth transistor is coupled to the second signal output terminal, and a second electrode of the tenth transistor is coupled to the first operating power supply terminal.

According to an embodiment of the present disclosure, the pull-up node is configured to provide a voltage at the active level in the preset time period, the driving signal output terminal is configured to provide a voltage at the active level in the preset time period, and the pull-down node is configured to provide a voltage at the inactive level in the preset time period.

According to an embodiment of the present disclosure, the first control signal input terminal is configured to provide a first clock signal, the second control signal input terminal is configured to provide a second clock signal, the first clock signal is at the active level in the preset time period, and the second clock signal is at the inactive level in the first sub-period and the third sub-period, and is at the active level in the second sub-period.

According to an embodiment of the present disclosure, the shift register includes a pre-charge reset circuit, a pull-up circuit, a pull-down circuit, and a pull-down control circuit;

the pre-charge reset circuit is coupled to a pre-charge signal input terminal and a reset signal input terminal, respectively, and coupled to the pull-up circuit at the pull-up node, the pull-down circuit and the pull-down control circuit are coupled at the pull-down node, and the pull-up circuit and the pull-down circuit are coupled at the driving signal output terminal.

According to an embodiment of the present disclosure, the pre-charge reset circuit includes an eleventh transistor, a twelfth transistor, and a thirteenth transistor; the pull-down control circuit includes a fourteenth transistor, a fifteenth transistor and a sixteenth transistor; the pull-up circuit includes a seventeenth transistor and a second capacitor; the pull-down circuit includes an eighteenth transistor;

a control electrode of the eleventh transistor is coupled to a fourth control signal input terminal, a first electrode of the eleventh transistor is coupled to the pre-charge signal input terminal, and a second electrode of the eleventh transistor is coupled to the pull-up node;

a control electrode of the twelfth transistor is coupled to the fourth control signal input terminal, a first electrode of the twelfth transistor is coupled to the pull-up node, and a second electrode of the twelfth transistor is coupled to a first electrode of the thirteenth transistor;

a control electrode of the thirteenth transistor is coupled to the reset signal input terminal, and a second electrode of the thirteenth transistor is coupled to the first operating power supply terminal;

a control electrode and a first electrode of the fourteenth transistor are respectively coupled to the second operating power supply terminal, and a second electrode of the fourteenth transistor is coupled to the pull-down node;

a control electrode of the fifteenth transistor is coupled to the pull-down node, a first electrode of the fifteenth transistor is coupled to the pull-up node, and a second electrode of the fifteenth transistor is coupled to the first operating power supply terminal;

a control electrode of the sixteenth transistor is coupled to the pull-up node, a first electrode of the sixteenth transistor is coupled to the pull-down node, and a second electrode of the sixteenth transistor is coupled to the first operating power supply terminal;

a control electrode of the seventeenth transistor is coupled to the pull-up node, a first electrode of the seventeenth transistor is coupled to a fifth control signal input terminal, and a second electrode of the seventeenth transistor is coupled to the driving signal output terminal;

a first terminal of the second capacitor is coupled to the pull-up node, and a second terminal of the second capacitor is coupled to the driving signal output terminal; and

a control electrode of the eighteenth transistor is coupled to the pull-down node, a first electrode of the eighteenth transistor is coupled to the driving signal output terminal, and a second electrode of the eighteenth transistor is coupled to the first operating power supply terminal.

According to an embodiment of the present disclosure, the pre-charge reset circuit includes an eleventh transistor, a twelfth transistor, and a thirteenth transistor; the pull-down control circuit includes a fourteenth transistor, a fifteenth transistor, a sixteenth transistor and a nineteenth transistor; the pull-up circuit includes a seventeenth transistor and a second capacitor; the pull-down circuit includes an eighteenth transistor;

a control electrode of the eleventh transistor is coupled to a fourth control signal input terminal, a first electrode of the eleventh transistor is coupled to the pre-charge signal input terminal, and a second electrode of the eleventh transistor is coupled to the pull-up node;

a control electrode of the twelfth transistor is coupled to the fourth control signal input terminal, a first electrode of the twelfth transistor is coupled to the pull-up node, and a second electrode of the twelfth transistor is coupled to a first electrode of the thirteenth transistor;

a control electrode of the thirteenth transistor is coupled to the reset signal input terminal, and a second electrode of the thirteenth transistor is coupled to the first operating power supply terminal;

a control electrode of the fourteenth transistor is coupled to the fourth control signal input terminal, a first electrode of the fourteenth transistor is coupled to the second operating power supply terminal, and a second electrode of the fourteenth transistor is coupled to the pull-down node;

a control electrode of the fifteenth transistor is coupled to the pull-down node, a first electrode of the fifteenth transistor is coupled to the pull-up node, and a second electrode of the fifteenth transistor is coupled to the first operating power supply terminal;

a control electrode of the sixteenth transistor is coupled to the pull-up node, a first electrode of the sixteenth transistor is coupled to the pull-down node, and a second electrode of the sixteenth transistor is coupled to the first operating power supply terminal;

a control electrode of the seventeenth transistor is coupled to the pull-up node, a first electrode of the seventeenth transistor is coupled to a fifth control signal input terminal, and a second electrode of the seventeenth transistor is coupled to the driving signal output terminal;

a first terminal of the second capacitor is coupled to the pull-up node, and a second terminal of the second capacitor is coupled to the driving signal output terminal;

a control electrode of the eighteenth transistor is coupled to the pull-down node, a first electrode of the eighteenth transistor is coupled to the driving signal output terminal, and a second electrode of the eighteenth transistor is coupled to the first operating power supply terminal; and

a control electrode of the nineteenth transistor is coupled to the fifth control signal input terminal, a first electrode of the nineteenth transistor is coupled to the second operating power supply terminal, and a second electrode of the nineteenth transistor is coupled to the pull-down node.

According to an embodiment of the present disclosure, all the transistors in the driving unit are transistors having a same conductivity type.

In another aspect, the present disclosure provides a gate driving circuit including: a plurality of cascaded driving units, wherein the driving unit is the driving unit according to the present disclosure;

the driving signal output terminal of the shift register of each of other driving units except a first-stage driving unit is coupled to a reset signal input terminal of the shift register of a previous-stage driving unit; and

the driving signal output terminal of the shift register of each of other driving units except a last-stage driving unit is coupled to a pre-charge signal input terminal of the shift register of a next-stage driving unit.

In another aspect, the present disclosure provides a display substrate including: the gate driving circuit according to the present disclosure.

In another aspect, the present disclosure provides a driving method for driving a driving unit, the driving unit being the driving unit according to the present disclosure, and the driving method including:

in the first sub-period, controlling, by the first control sub-circuit, the voltage at the first node to be at the active level, and controlling, by the second control sub-circuit, the voltage at the second node to be at the inactive level, so that the output sub-circuit outputs the voltage at the active level through the first signal output terminal;

in the second sub-period, controlling, by the first control sub-circuit, the voltage at the first node to be at the active level, and controlling, by the second control sub-circuit, the voltage at the second node to be at the active level, so that the output sub-circuit outputs the voltage at the inactive level through the first signal output terminal; and

in the third sub-period, controlling, by the first control sub-circuit, the voltage at the first node to be at the active level, and controlling, by the second control sub-circuit, the voltage at the second node to be at the inactive level, so that the output sub-circuit outputs the voltage at the active level through the first signal output terminal.

According to an embodiment of the present disclosure, in the preset time period, the voltage of the pull-up node is at the active level, the voltage of the pull-down node is at the inactive level, and the voltage provided through the driving signal output terminal is at the active level.

According to an embodiment of the present disclosure, an operating cycle of the shift register includes a pre-charge stage, an output stage and a reset stage,

in the pre-charge stage, the pull-up node is pre-charged;

in the output stage, a voltage at the active level is output through the driving signal output terminal under control of the voltage of the pull-up node;

in the reset stage, the pull-up node is reset, the voltage of the pull-down node is controlled to be at the active level, and a voltage at the inactive level is output through the driving signal output terminal, and

the preset time period is within the output stage.

