Provided is a memory device with a reduced layout area. The memory device includes a sense amplifier electrically connected to first and second wirings and positioned in a first layer, and first and second circuits positioned in a second layer over the first layer. The first circuit includes a first switch being turned on and off in accordance with a potential of a third wiring, and a first capacitor electrically connected to the first wiring via the first switch. The second circuit includes a second switch being turned on and off in accordance with a potential of a fourth wiring, and a second capacitor electrically connected to the second wiring via the second switch. The first wiring intersects the third wiring and does not intersect the fourth wiring in the second layer. The second wiring intersects the fourth wiring and does not intersect the third wiring in the second layer.