Apple Inc.
Threshold voltage hysteresis compensation

Abstract:

Electronic devices, storage medium containing instructions, and methods pertain to determining a target boosted threshold voltage level based at least in part on a target emission threshold voltage level. Using the determined target boosted threshold voltage level, a light emitting diode (LED)-controlling transistor is submitted to voltage stress to boost a threshold voltage of the transistor to the target boosted threshold voltage level during a first portion of a refresh period between first and second emission periods. During a second portion of the refresh period, the voltage stress is de-asserted to settle the threshold voltage to a target emission threshold voltage level for the second emission period. After the voltage is settled, the LED-controlling transistor is driven based at least in part on the target emission threshold voltage level.