Driving scheme for emissive displays providing compensation for driving transistor variations

摘要

Systems and methods detect and compensate for process or performance-related non-uniformities and/or degradation in displays. The systems and methods can compare a device current with one or more reference currents to generate an output signal indicative of the difference between the device and reference currents. This output voltage can be amplified, and quantized and then be used to determine how the device current differs from the reference current and to adjust the programming voltage for the device of interest accordingly.

主权项

1. A method of compensating for deviations by a measured device current from a reference current in a display having a plurality of pixel circuits each including a storage device, a drive transistor, and a light emitting device, the method comprising:
performing a first reset operation on an integration circuit, the reset operation restoring the integration circuit to a first known state; performing a first current integration operation at the integration circuit, the integration operation operative to integrate a first input current corresponding to a difference between a reference current and a measured first device current flowing through the drive transistor or the light emitting device of a selected one of the pixel circuits; storing a first voltage corresponding to the first current integration operation on a first storage capacitor; performing a second reset operation on the integration circuit, the reset operation restoring the integration circuit to a second known state; performing a second current integration operation at the integration circuit, the integration operation operative to integrate a second input current corresponding to the leakage current on a reference line; storing a second voltage corresponding to the second current integration operation on a second storage capacitor; generating an amplified output voltage corresponding to the difference between the first voltage and the second voltage using one or more amplifiers; and quantizing the amplified output voltage.