Image sensors in which pixel array and memory cell array are merged and electronic devices including the same

An image sensor, comprising:

• a first semiconductor chip including a pixel array and a dynamic random access memory (DRAM) cell array in a same semiconductor chip;
• and
• a second semiconductor chip overlapping the first semiconductor chip in a vertical direction, the second semiconductor chip configured to control the pixel array and the DRAM cell array,
• wherein the second semiconductor chip is configured to
• receive an analog signal output from the pixel array through a first path between the first semiconductor chip and the second semiconductor chip,
• convert the analog signal to a digital signal, and
• transmit data that is based on the digital signal to the DRAM cell array of the first semiconductor chip through a second path between the first semiconductor chip and the second semiconductor chip.

An electronic device, comprising:

• an image sensor including a first semiconductor chip and a second semiconductor chip, the second semiconductor chip overlapping the first semiconductor chip in a vertical direction;
• and
• a host configured to receive and process output data output from the image sensor,
• wherein the first semiconductor chip includes a pixel array and a memory cell array in a same semiconductor chip, and
• wherein the second semiconductor chip is configured to convert an analog signal output from the pixel array to a digital signal and store image data based on the digital signal to the memory cell array of the first semiconductor chip.