Device and method for improved LED driving

1. A display pixel comprising:

a light-emitting diode having a cathode terminal coupled to ground and having an anode terminal;

a drive transistor coupled in series with the light-emitting diode and having a gate terminal;

a first transistor having a first source-drain terminal coupled to the anode terminal and having a second source-drain terminal configured to receive a reference voltage; and

a second transistor having a first terminal coupled at a source-drain terminal of the drive transistor and having a second terminal configured to receive a reset voltage separate from the reference voltage.

2. The display pixel of claim 1 , wherein the second transistor comprises semiconducting oxide material.

3. The display pixel of claim 2 , further comprising:

a first emission transistor coupled between the drive transistor and a positive power supply line; and

a second emission transistor coupled between the drive transistor and the light-emitting diode.

4. The display pixel of claim 3 , wherein the second transistor is activated at a rate different than a refresh rate of the display pixel.

5. The display pixel of claim 3 , wherein when a refresh rate of the display pixel is greater than 10 Hz, the second transistor is activated at a rate equal to the refresh rate.

6. The display pixel of claim 5 , wherein when the refresh rate of the display pixel is less than 10 Hz, the second transistor is activated at a rate greater than the refresh rate.

7. A display pixel comprising:

a light-emitting diode having a cathode terminal coupled to ground and having an anode terminal;

a drive transistor coupled in series with the light-emitting diode and having a gate terminal;

a first transistor having a first terminal coupled to the anode terminal and having a second terminal configured to receive a reference voltage; and

a second transistor having a first terminal coupled to the drive transistor and having a second terminal configured to receive a reset voltage separate from the reference voltage, wherein the second transistor is activated at a rate greater than a refresh rate of the display pixel.

8. An electronic device comprising:

a display having a plurality of pixels, each of which comprises a light-emitting diode, a drive transistor, an initialization transistor having a first source-drain terminal coupled to an anode of the light-emitting diode and having a second source-drain terminal configured to receive a reference voltage, and an anode reset transistor configured to receive a reset voltage separate from the reference voltage; and

a controller configured to:

provide data signals to the plurality of pixels at a refresh rate; and

activate the anode reset transistor at a rate different than the refresh rate.

9. The electronic device of claim 8 , wherein the controller is configured to activate the anode reset transistor at a rate greater than the refresh rate.

10. The electronic device of claim 8 , wherein the controller is further configured to activate the anode reset transistor at a rate equal to the refresh rate.

11. The electronic device of claim 8 , wherein the controller is further configured to:

detect a change in the refresh rate; and

adjust the rate at which to activate the anode reset transistor based on the detected change in the refresh rate.

12. The electronic device of claim 8 , wherein each pixel in the plurality of pixels further comprises an emission transistor that is deactivated when the anode reset transistor is activated.

13. The electronic device of claim 8 , wherein the anode reset transistor is directly coupled to the light-emitting diode.

14. The electronic device of claim 8 , wherein the anode reset transistor is directly coupled to the drive transistor.