Stable driving scheme for active matrix displays

A display system comprising:

• a pixel array including a plurality of pixel circuits and a plurality of lines for operation of the plurality of pixel circuits, each of the pixel circuits having a switch, a select line connected to the switch, a light emitting device, a storage capacitor, and a drive transistor connected to the light emitting device and the storage capacitor, the drive transistor being connected to a data line via the switch and to a power supply line;
• a driver for operating the plurality of lines to repeat an operation cycle having a frame period so that each of the operation cycle comprises a programming cycle, a driving cycle and a relaxing cycle for relaxing a stress on a pixel circuit of the pixel array, prior to a next frame period;
• and
• a controller coupled to the driver, the controller operable to:
• program during the programming cycle a first of the pixel circuits responsive to driving the select line from a first state to a second state to select the first pixel circuit for programming by providing a programming data on the data line,
• responsive to programming the first pixel circuit, drive the first pixel circuit during the driving cycle responsive to driving the select line from the second state to the first state, and
• responsive to driving the first pixel circuit, relax a stress effect on the first pixel circuit during the relaxing cycle, prior to the next frame period, by driving the select line from the first state to the second state during a first operating cycle of the relaxing cycle followed by driving the select line from the second state to the first state during a second operating cycle of the relaxing cycle so that the pixel circuit is off during the second operating cycle, wherein during the first operating cycle, the data line is changed to a voltage smaller than VT0+VOLED0, where VTO is a threshold voltage of the drive transistor in an unstressed state and VOLED0 is an ON voltage of the light emitting device in an unstressed state, wherein the first pixel circuit is off at the second operating cycle, and wherein the power supply line has a positive voltage during the driving cycle and the relaxing cycle.