Patent ID: 9478704
Filing Date: 2016-10-25
CPC Classification: G02F,G09G,H01L

Claim Text:
1. A semiconductor display device comprising: a pixel portion comprising a display element and a first transistor; a driver circuit; and a CPU comprising: wherein one of a source terminal and a drain terminal of the second transistor is electrically connected to an output terminal of the first memory circuit, wherein the other of the source terminal and the drain terminal of the second transistor is electrically connected to one electrode of the first capacitor, wherein the pixel portion is configured to display a still image after the driver circuit stops supplying an image signal to the pixel portion, wherein the second memory circuit is configured to store data stored in the first memory circuit before the CPU stops, and wherein each of the first transistor and the second transistor comprises a semiconductor whose bandgap is wider than bandgap of silicon in a channel formation region.