An architecture for a chip-scale optical phased array-based scanning frequency-modulated continuous wave (FMCW) Light-detection and ranging (LiDAR) device is described. The LiDAR device includes a laser, a transmit optical splitter, an optical circulator, photodetectors, and an optical phased array. The laser, the transmit optical splitter, the optical circulator, the photodetectors, and the optical phased array are arranged as a chip-scale package on a single semiconductor substrate. The laser generates a first light beam that is transmitted to the optical phased array aperture via the transmit optical splitter, the optical circulator, and the optical phased array. A fraction of the first light beam is transmitted to the photodetectors via the transmit optical splitter to serve as the optical local oscillator (LO), the aperture of the optical phased array captures a second light beam that is transmitted to the photodetectors via the optical phased array and the optical circulator.