An electronic device includes a time of flight (ToF) sensor including a pixel array, a light source that emits light signals, and an optical device that projects the light signals to areas of an object which respectively correspond to a plurality of pixel blocks including pixels of the pixel array. Each of the pixels includes a plurality of taps each including a photo transistor, a first transfer transistor connected with the photo transistor, a storage element connected with the first transfer transistor, a second transfer transistor connected with the storage element, a floating diffusion area connected with the second transfer transistor, and a readout circuit connected with the floating diffusion area. An overflow transistor is disposed adjacent to the photo transistor and connected with a power supply voltage.