Power-off discharge circuit and operation method of display panel, and display substrate

1. A power-off discharge circuit for a display panel, the display panel comprising a power management circuit and a gate driving circuit, wherein a first output terminal of the power management circuit is coupled to a first input terminal of the gate driving circuit via a first transmission line, and a second output terminal of the power management circuit is coupled to a second input terminal of the gate driving circuit via a second transmission line, and the power-off discharge circuit comprises:

a switching circuit, coupled to the first transmission line and the second transmission line and configured to control a connection between the first transmission line and the second transmission line in response to a first control signal, and to control a connection between the second output terminal of the power management circuit and the second input terminal of the gate driving circuit in response to a second control signal;

a power storage circuit, coupled to the first transmission line and configured to perform, in response to a power control signal, one of storing power transmitted from the first transmission line and supplying stored power to the first transmission line, and

a one-way conduction circuit coupled between the switching circuit and the second input terminal of the gate driving circuit and configured to only allow a current to flow from the switching circuit to the second input terminal of the gate driving circuit.

2. The power-off discharge circuit according to claim 1 , further comprising a first discharge circuit coupled to data lines of the display panel and configured to control a connection between the data lines and a ground in response to a third control signal.

3. The power-off discharge circuit according to claim 2 , further comprising a second discharge circuit coupled to the second output terminal of the power management circuit and the power storage circuit and configured to control a connection between the second output terminal of the power management circuit and the ground in response to a fourth control signal from the power storage circuit.

4. The power-off discharge circuit according to claim 3 , wherein the power storage circuit comprises: a first transistor, a second transistor, a first resistor, a second resistor, and a storage capacitor;

a control electrode of the first transistor is coupled to a second terminal of the first resistor and a first terminal of the second resistor respectively, a first electrode of the first transistor is coupled to a first terminal of the storage capacitor, and a second electrode of the first transistor is coupled to a first terminal of the first resistor and the first transmission line respectively;

a control electrode of the second transistor is coupled to a power control terminal of the power management circuit, a first electrode of the second transistor is coupled to the second output terminal of the power management circuit, and a second electrode of the second transistor is coupled to a second terminal of the second resistor; and

a second terminal of the storage capacitor is grounded.

5. The power-off discharge circuit according to claim 4 , wherein the switching circuit comprises a fourth transistor and a fifth transistor;

a control electrode of the fourth transistor is coupled to a first control signal line for supplying the first control signal, a first electrode of the fourth transistor is coupled to the first transmission line, and a second electrode of the fourth transistor is coupled to the second transmission line; and

a control electrode of the fifth transistor is coupled to a second control signal line for supplying the second control signal, a first electrode of the fifth transistor is coupled to the second output terminal of the power management circuit, and a second electrode of the fifth transistor is coupled to the second input terminal of the gate driving circuit.

6. The power-off discharge circuit according to claim 5 , wherein the first discharge circuit comprises a plurality of sixth transistors in one-to-one correspondence with the data lines; and

control electrodes of the plurality of sixth transistors are respectively coupled to a discharge control terminal for supplying the third control signal, first electrodes of the plurality of sixth transistors are respectively coupled to corresponding data lines, and second electrodes of the plurality of sixth transistors are grounded.

7. The power-off discharge circuit according to claim 6 , wherein the second discharge circuit comprises a third transistor, and

a control electrode of the third transistor is coupled to the second terminal of the second resistor, a first electrode of the third transistor is grounded, and a second electrode of the third transistor is coupled to the second output terminal of the power management circuit.

8. The power-off discharge circuit according to claim 7 , wherein the one-way conduction circuit comprises a diode; and

an anode of the diode is coupled to the second electrode of the fifth transistor, and a cathode of the diode is coupled to the second input terminal of the gate driving circuit.

9. The power-off discharge circuit according to claim 8 , wherein

the first transistor has a first conductive type; and

each of the second transistor, the third transistor, the fourth transistor, the fifth transistor, and the sixth transistor has a second conductive type different from the first conductive type.

10. A display substrate, comprising the power-off discharge circuit according to claim 1 .

11. A method for operating a display panel, the display panel comprising a power management circuit and a gate driving circuit, wherein a first output terminal of the power management circuit is coupled to a first input terminal of the gate driving circuit via a first transmission line, and a second output terminal of the power management circuit is coupled to a second input terminal of the gate driving circuit via a second transmission line, and the method comprises during a power-off stage of the display panel:

coupling, by a switching circuit, the first transmission line to the second transmission line, and disconnecting the second transmission line from the power management circuit;

supplying, by a power storage circuit, power stored in the power storage circuit to the first transmission line, such that the gate driving circuit outputs an active level; and

only allowing, by a one-way conduction circuit, a current to flow from the switching circuit to the second input terminal of the gate driving circuit.

12. The method according to claim 11 , further comprising during a display stage of the display panel:

coupling, by the switching circuit, the first output terminal of the power management circuit to the first input terminal of the gate driving circuit via the first transmission line, and coupling, by the switching circuit, the second output terminal of the power management circuit to the second input terminal of the gate driving circuit via the second transmission line.

13. The method according to claim 11 , further comprising:

storing, by the power storage circuit, a part of power output from the power management circuit during a display stage of the display panel.

14. The method according to claim 11 , further comprising:

coupling, by a first discharge circuit, data lines of the display panel to a ground so as to discharge pixel electrodes in the display panel during the power-off stage of the display panel.

15. The method according to claim 14 , further comprising:

disconnecting, by the first discharge circuit, the data lines from the ground during a display stage of the display panel.

16. The method according to claim 11 , further comprising:

coupling, by a second discharge circuit, the second output terminal of the power management circuit to ground so as to discharge the power management circuit during the power-off stage of the display panel.