Sensing Circuit and Display Device Including the Same

A display device comprising:

• a first external power line configured to supply a pixel driving voltage;
• a second external power line configured to supply the pixel driving voltage;
• a pixel power line connected to the first external power line and the second external power line, the pixel power line configured to receive the pixel driving voltage from the first external power line or the second external power line;
• a first selection switch element connected between the first external power line and a voltage source, the first selection switch element configured to connect the voltage source and the first external power line responsive to a first signal;
• a current sensor connected between the second external power line and the pixel power line;
• a second selection switch element connected between the current sensor and the voltage source, the second selection switch element configured to connect the voltage source and the second external power line responsive to a second signal;
• and
• a display panel including a subpixel connected to the pixel power line, the subpixel including a light emitting element configured to emit light,
• wherein during a sensing period during which an electrical characteristic of a part of the subpixel is sensed, the second selection switch element is turned on responsive to the second signal and the first selection switch element is turned off to connect the second external power line and the voltage source such that a current flowing through the second external power line is measured by the current sensor during the sensing period, and the pixel driving voltage is supplied to the subpixel from the pixel power line via the second external power line without the light emitting element emitting light during the sensing period.

A display device comprising:

• a display panel including a plurality of pixels that are connected to a pixel power line to which a pixel driving voltage is supplied, the plurality of pixels divided into a plurality of rows of pixel blocks that extend along a first direction and each pixel block including a different subset of pixels from the plurality of pixels;
• a plurality of data lines that are connected to the plurality of pixels, the plurality of data lines extending along a second direction that intersects the first direction;
• a plurality of gate lines that are connected to the plurality of pixels and extend along the first direction, the plurality of gate lines applying gate signals to the plurality of pixels;
• a data driver configured to supply a plurality of data voltages of an image to the plurality of data lines during an image display period, and to supply sensing data to the plurality of data lines during a sensing period;
• and
• a sensing circuit configured to sense current flowing through the pixel power line that is connected to a subset of the plurality of pixels included in a pixel block from the plurality of pixel blocks during the sensing period based on the sensing data supplied to the respective subset of pixels during the sensing period, the sensing circuit including:
• a first external power line that supplies the pixel driving voltage, the first external power line connected to the pixel power line;
• a second external power line that supplies the pixel driving voltage, the second external power line connected to the pixel power line;
• a first selection switch element connected between the first external power line and a voltage source, the first selection switch element configured to connect the voltage source and the first external power line such that the first external power line supplies the pixel driving voltage to the pixel power line responsive to a first signal;
• a current sensor connected between the second external power line and the pixel power line;
• and
• a second selection switch element connected between the current sensor and the voltage source, the second selection switch element configured to connect the voltage source and the second external power line such that the second external power line supplies the pixel driving voltage to the pixel power line responsive to a second signal.